Warming oceans are stressing diatoms and, in some situations, reducing their numbers.
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A massive phytoplankton bloom, including diatoms, in the Barents Sea north of Norway in 2011.
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They found that the sediment collected from the skull site contained fossilized deep sea diatoms.
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When diatoms die, they form a tiny shell around them and then sink to the bottom.
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If we can find marine diatoms, this may indicate that the body is a tsunami victim.
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"Diatomaceous earth is made from the fossilized remains of tiny aquatic organisms called diatoms," Brust says.
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According to Kate Cummings of the Blue Ocean Whale Watch, this is because of algae called diatoms.
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The coccolithophores thrive in areas rich in nitrate and relatively low in iron—another key nutrient for diatoms.
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Diatoms, for example, are big, sink to the ocean floor very fast and need a lot of nutrients.
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Sculptures inspired by insects, orchids, birds and diatoms, as well as the utilitarian constructs from his Tin Man series.
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Eventually these heavy diatoms sink to the ocean floor, where they naturally "sequester" this carbon far from the atmosphere.
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The second was far less typical: close-ups of diatoms, butterfly wings, snail tongue, whalebone—all taken through a microscope.
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At the bottom of the world atop the forbidding Transantarctic Mountains sit the fossilized remains of microscopic, ocean-dwelling diatoms.
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He found the shells of diatoms (single-celled algae) and the skeletal fragments of sea sponges littered throughout the lake's mud.
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They found that more acidic waters hindered diatoms from getting the nutrition they need, specifically iron, for their numbers to grow.
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Layers laid down after the 1920s are full of Asterionella formosa and Synedra nana, diatoms that thrive in nutrient-polluted lakes.
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Scientists have now identified a climate change-related threat to diatoms, and it comes from a known and growing threat: Ocean acidification.
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"These sediments that the Aitape skull was in have pure marine diatoms in them, which is ocean water that's inundating it," explained Golitko.
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The researchers measured the concentrations of barium and opal, which are respectively associated with organic carbon sequestration and the abundance of marine diatoms.
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The bedrock of the ocean's food chain, on which whales, sharks, and octopi ultimately rely, are tiny bits of photosynthetic algae called diatoms.
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But out in the open ocean, the effects on diatoms could be different — and may not result in such an adverse feedback loop.
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The silt was mixed with glass-like microalgae called diatoms, and, reflecting the bright light emitted by the sub's LEDs, it dazzled him.
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Diatoms float near the ocean's sunlit surface, and they suck carbon dioxide from the atmosphere and then use this carbon as a key nutrient.
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Carbon is absorbed this way as dead diatoms and plankton descend through the water column, accumulating slowly but steadily as "marine snow" on the seafloor.
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In the dynamicist view, the diatoms were brought to their present location by the migration of glaciers as Earth's climate went from hot to cold.
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Goff's team put the sediment under a microscope and counted the diatoms, which allowed them to determine the temperature, salinity, and energy of the water when they died.
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And this is key: The researchers found that fewer carbonate molecules interfere with diatoms' ability to "grab" onto iron — a vital nutrient that enables them to multiply and flourish.
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In the ocean waters of the southern hemisphere, coccolithophores compete with other kinds of algae, such as large diatoms, which need large amounts of silicate to build their glassy shells.
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Importantly, they also discovered the presence of preserved diatoms—small, single-celled aquatic creatures that can be used to paint a picture of what water conditions were like at the time.
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Carl Strüwe never gained fame during his lifetime, but over the decades his stark images of diatoms, spermatozoa and other life under the microscope have gathered admirers for their distinctive artistry.
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Archetype of Individuality, 1933 Diatoms Actinoptychus heliopelta, 1928 Conical Shape (Crystal of Said Hippuric Acid Compound), 1927 Diatoms (Triceratium favus), 1930 Butterfly (Red Admiral), Scales on Wing (Ala papilionis), 19523 Notched Butterfly Proboscis (Macroglossa stellatarum L.), 1928 Finale (Other Title: End Time - Melancholy), 1959 The insect trachea illustrated here are only one of many kinds of adaptive adjustments to increased size found in large organisms (Life: 1957), 1937 Chewing Stomach of Kitchen-schabe, Cockroach, 1928 Lead.
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Since 3-million year-old diatoms were first discovered in the Transantarctic mountain range that separates East and West Antarctica in 1984, they've been at the center of an intense scientific debate.
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According to the National Oceanic and Atmospheric Administration (NOAA), the ocean absorbs 30 percent of the carbon dioxide in the atmosphere, and much of this is consumed by hungry, surface-dwelling diatoms.
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In the sea and along its shores swarm organisms of the other living world — marine diatoms, crustaceans, ascidians, sea hares, priapulids, coral, loriciferans and on through the still mostly unfilled encyclopedia of life.
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I liked reading about diatoms and stars, things from four hundred million years ago or a hundred thousand years from now, life in sand dunes or tidal pools, under the ice or on the tops of mountains.
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Horwitz rigorously demonstrates that when simple systems emerge randomly and are repeated enough times they eventually produce seashells, flowers, diatoms, and all manner of organic and inorganic arrangements; in short, life and the world as we know it.
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"When people die in a tsunami, they inhale saltwater that contains small marine microorganisms called diatoms, which means they suffocate and then drown," Genevieve Cain, the lead author of the new study and a researcher at the University of Oxford, said in a statement.
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Diatoms are mostly non-motile; however, sperm found in some species can be flagellated, though motility is usually limited to a gliding motion. In centric diatoms, the small male gametes have one flagellum while the female gametes are large and non-motile (oogamous). Conversely, in pennate diatoms both gametes lack flagella (isoogamous). Certain araphid species, that is pennate diatoms without a raphe (seam), have been documented as anisogamous and are, therefore, considered to represent a transitional stage between centric and raphid pennate diatoms, diatoms with a raphe.
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The study of diatoms is a branch of phycology. Diatoms are classified as eukaryotes, organisms with a membrane-bound cell nucleus, that separates them from the prokaryotes archaea and bacteria. Diatoms are a type of plankton called phytoplankton, the most common of the plankton types. Diatoms also grow attached to benthic substrates, floating debris, and on macrophytes.
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Both regions are abundant with diatoms; small diatoms (cell volume = 30.5μm³) such as Cyclotella stelligera, Synedra radians make up the majority in the epilimnion, while larger diatoms (cell volume = 416.3μm³) such as C.ocellata, Stephanodiscus alpinus, Fragilaria crotonensis, dominate the DCM.
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Identifying Marine Phytoplankton, Academic Press. Often found in long chains in coastal waters, it frequently acts as an attachment platform for other diatoms. Tiffany, M.A., Lange, C.B., (2002). "Diatoms provide attachment sites for other diatoms: a natural history of epiphytism form southern California", Journal of Phycology.
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Some early diatoms were larger, and could be between 0.2 and 22mm in diameter. The earliest diatoms were radial centrics, and lived in shallow water close to shore. These early diatoms were adapted to live on the benthos, as their outer shells were heavy and prevented them from free-floating. Free- floating diatoms, known as bipolar and multipolar centrics, began evolving approximately 100 million years ago during the Cretaceous.
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Fucoxanthin is present in brown seaweeds and diatoms and was first isolated from Fucus, Dictyota, and Laminaria by Willstätter and Page in 1914. Seaweeds are common food south-east Asia and certain countries in Europe while Diatoms are single cell planktonic microalgae characterized by golden-brown color due to the high amount of Fucoxanthin. Generally, diatoms contain up to 4 times more Fucoxanthin compared to seaweed, making diatoms a viable source for fucoxanthin industrialization. Diatoms can be grown in controlled environments (such as photobioreactors), brown seaweeds are mostly grown in the open sea often exposed to metals and metalloids.
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Diatoms have two distinct shapes: a few (centric diatoms) are radially symmetric, while most (pennate diatoms) are broadly bilaterally symmetric. A unique feature of diatom anatomy is that they are surrounded by a cell wall made of silica (hydrated silicon dioxide), called a frustule. These frustules have structural coloration due to their photonic nanostructure, prompting them to be described as "jewels of the sea" and "living opals". Movement in diatoms primarily occurs passively as a result of both water currents and wind-induced water turbulence; however, male gametes of centric diatoms have flagella, permitting active movement for seeking female gametes.
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In early spring and the fall the ratio of living diatoms to dead diatoms is high, whereas, in summer and winter the amount of dead diatoms outpopulates the living. Based on this known information diatoms can verify the time of year samples were taken. Different types of diatoms can also determine the properties of a samples ecosystem. For example, the higher ratio of periphytic (type of platonic diatom), the higher the vegetation concentration and shallower the water, but the higher the ratio of scaled chrysophytes a sample means the environment of that organism contains more open water.
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Diatoms can be obtained from multiple sources.Chamberlain, C. J. (1901) Methods in Plant Histology, University of Chicago Press, USA Marine diatoms can be collected by direct water sampling, and benthic forms can be secured by scraping barnacles, oyster and other shells. Diatoms are frequently present as a brown, slippery coating on submerged stones and sticks, and may be seen to "stream" with river current. The surface mud of a pond, ditch, or lagoon will almost always yield some diatoms.
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Skeletonemataceae is a family of diatoms in the order Thalassiosirales. There is currently only one known genera in this family of diatoms known as Skeletonema as reported from diatom.org. Being from the thalassiosirales order means that skeletonemataceae are centric diatoms. The sexual reproduction of oogamous is where reproduction occurs by the union of mobile male and immobile female gametes.
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Surirellaceae is a family of diatoms in the order Surirellales.
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Navicella is a genus of diatoms in the family Cymbellaceae.
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Unusually, diatoms have a cell wall composed of biogenic silica.
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His contributions to biology include fine structure analyses of diatoms.
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Stilus is a genus of diatoms in the family Plagiotropidaceae.
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Plagiotropidaceae is a family of diatoms in the order Naviculales.
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Cymatosiraceae is a family of diatoms in the order Cymatosirales.
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Surirella is a genus of diatoms in the family Surirellaceae.
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Campylodiscus is a genus of diatoms in the family Surirellaceae.
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Cymatosirales is an order of diatoms in the superorder Cymatosirophycidae.
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Cymatosirophycidae is a suborder of diatoms in the classe Coscinodiscophyceae.
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Craspedodiscus is a genus of diatoms in the family Coscinodiscaceae.
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Diatoms are primary producers that convert carbon dioxide into organic carbon via photosynthesis, and export organic carbon from the surface ocean to the deep sea via the biological pump. Diatoms can therefore be a significant sink for carbon dioxide in surface waters. Due to the relatively large size of diatoms (when compared to other phytoplankton), they are able to take up more total carbon dioxide. Additionally, diatoms do not release carbon dioxide into the environment during formation of their opal silicate shells.
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For example, diatoms from the Eocene epoch (approximately 40 to 50 million years old) are not as effective in their ability to absorb fluids because older diatoms recrystallize, their small pores becoming filled with silica.
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Campylodiscus elegans is a species of diatoms in the family Surirellaceae.
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The taxonomic assemblages of diatoms reflect many aspects of the lake temperature, chemical, and nutrient environment. Diatoms are particularly suited to paleolimnology due to their silica-based frustules, which preserve in sufficient condition and in large enough quantities to be identified down to the species level. Diatoms have been examined in conjunction with chrysophycean statospores to estimate nutrient conditions of prehistoric temperate lakes.
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The oldest well-preserved diatom fossils have been dated to the beginning of the Jurassic period. However, the molecular record suggests diatoms evolved at least 250 million years ago during the Triassic. As new species of diatoms evolved and spread, oceanic silica levels began to decrease. Today, there are an estimated 100,000 species of diatoms, most of which are microscopic (2-200 μm).
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In cases involving a body of water at or near the scene of a crime, a sample of the water can be extracted and analyzed under a light microscope for microorganisms. One such microorganism that are analyzed within samples of fresh water are diatoms, microscopic algae of varying shapes. Different bodies of water have been found to contain unique sets of diatoms and therefore, a piece of evidence found in a specific body of water will contain unique diatoms on it found only in that specific body of water. Therefore, the diatoms on a questioned object or body can be compared to the diatoms from a body of water to determine whether it had been present in the water.
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Tertiarius is a genus of freshwater diatoms known from the fossil record.
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Cocconeis elegans is a species of diatoms. It is found in Sicily.
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Surirella elegans is a species of freshwater diatoms in the family Surirellaceae.
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Climacosphenia is a genus of marine pennate diatoms in the order Fragilariophyceae.
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Out of the 771 cases in 2001, only 28% were fresh water drowning. Living diatoms do not inhabit domestic water sources, which limits the situations that diatoms can be used to create flora profiles or time of death estimations. Diatoms can only tell when or where evidence was found in some situations and not the time of death if there is no body fluid sample available to be collected. If a body is placed in freshwater post mortem then diatoms cannot be used to evaluate time of death.
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Planktonic diatoms such as Chaetoceros often grow in chains, and have features such as spines which slow sinking rates by increasing drag. Some Thalassiosira diatoms form chain- like colonies, like these ones collected near the Antarctic peninsula coast by the schooner of the Tara Oceans Expedition for plankton research. This confocal image shows the diatoms' cell wall (cyan), chloroplasts (red), DNA (blue), membranes and organelles (green).
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Frontiers in microbiology, 8: 1239. . 50px Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License. Selections from Ernst Haeckel's 1904 Kunstformen der Natur (Art Forms of Nature), showing pennate (left) and centric (right) frustules. Diatoms are divided into two groups that are distinguished by the shape of the frustule: the centric diatoms and the pennate diatoms.
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Bacilladnaviridae is a family of single-stranded DNA viruses that primarily infect diatoms.
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The islands also contain 5 species of fungus, 41 lichens and 16 diatoms.
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Climacosphenia elegans is a species of marine pennate diatoms in the order Fragilariophyceae.
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Eunotia is a genus of diatoms. They are fresh water diatoms, specifically common in lakes, and they are also common in fossil records, although their siliceous wall design may have been lost and they appear plane, an example is Eunotia tetradon.
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The deposition of silica by diatoms may also prove to be of utility to nanotechnology. Diatom cells repeatedly and reliably manufacture valves of various shapes and sizes, potentially allowing diatoms to manufacture micro- or nano-scale structures which may be of use in a range of devices, including: optical systems; semiconductor nanolithography; and even vehicles for drug delivery. With an appropriate artificial selection procedure, diatoms that produce valves of particular shapes and sizes might be evolved for cultivation in chemostat cultures to mass-produce nanoscale components. It has also been proposed that diatoms could be used as a component of solar cells by substituting photosensitive titanium dioxide for the silicon dioxide that diatoms normally use to create their cell walls.
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The exact purpose of these biofilms is unknown, however there is evidence that the EPS produced by diatoms facilitates both cold and salinity stress. These eukaryotes interact with a diverse range of other organisms within a region known as the phycosphere, but importantly are the bacteria associated with diatoms, as it has been shown that although diatoms excrete EPS, they only do so when interacting with certain bacteria species.
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Diatoms are identifiable based on each species unique silica cell walls and vary depending on their environment. Because they have determinant properties diatoms create flora profiles for scientists. When these microscopic algae die, their frustules (silica cell walls) becomes a part of the water sediment. The presence of the frustules enables scientists to compare the cell walls of the deceased organisms with the living diatoms to determine characteristics of their environment.
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When diatom testing on an organic sample scientists use phase contrast microscopy. While observing the diatoms are tallied and organized based on their different species. The ratio of specific specimen of diatoms in the water will have a similar ratio to the sample that is taken from the site where the diatoms were transferred. Scientists use this to match materials and people to specific locations at a crime scene.
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Silicified cell wall of an Amphora species consisting of two valves or overlapping halves Amphora is a major genus of marine and freshwater diatoms. With over 1000 species, it is one of the largest genera of diatoms. These diatoms are recognized by their strongly dorsiventral frustules, which means that their ridges lie close to the ventral margin of the valve, and their girdle is much wider on the dorsal side.
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Long exposure image of bioluminescence of N. scintillans in the yacht port of Zeebrugge, Belgium N. scintillans is a heterotroph that engulfs, by phagocytosis, food which includes plankton, diatoms, other dinoflagellates, fish eggs, and bacteria. Diatoms are often found in the vacuoles within these single-celled creatures. These green nonfeeding symbioses can grow photoautotrophically for generations. Diatoms of Thalassiosira have been noted as a favored food source of these organisms.
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Phytobenthos comprises the plants belonging to the benthos, mainly benthic diatoms and macroalgae (seaweed).
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They feed by grazing on diatoms. Little or no life history information is available.
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Nassellarians feed on other plankton such as small algae, bacteria, diatoms, and small zooplankton.
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A feature of diatoms is the urea cycle, which links them evolutionarily to animals. This was discovered in research carried out by Andrew Allen, Chris Bowler and colleagues. Their findings, published in 2011, that diatoms have a functioning urea cycle was highly significant, since prior to this, the urea cycle was thought to have originated with the metazoans which appeared several hundreds of millions of years after the diatoms. Their study showed that while diatoms and animals use the urea cycle for different ends, they are seen to be evolutionarily linked in such a way that animals and plants are not.
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Major pigments of diatoms are chlorophylls a and c, beta- carotene, fucoxanthin, diatoxanthin and diadinoxanthin.
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Siliceous microfossils include diatoms, radiolarians, silicoflagellates, ebridians, phytoliths, some scolecodonts ("worm" jaws), and sponge spicules.
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Over 75% of the species exist nowhere else in the world. Mackay has studied the numbers of the microalgae diatoms in Lake Baikal, and showed that they have declined as the lake gets warmer. Some diatoms are more sensitive than others, which lets Mackay and colleagues look at the impact of pollution in the past. He studies the populations of diatoms by studying silicon isotopes, which form the base of the diatom food chain.
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Environmental, mechanical, or chemical cues can all trigger this release. Diatoms are single celled phytoplankton that can occur as individuals or as long chains. They can reproduce sexually and asexually. Diatoms are important oxygen producers and are usually the first step in the food chain.
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Cocconeis is a genus of diatoms. Members of the genus are elliptically shaped diatoms. The green alga Cladophora is frequently covered with Cocconeis, as are individuals of Antarctic minke whales, often found with orange-brown to yellowish patches of Cocconeis ceticola on their bodies.
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Valvata utahensis is primarily a detritivore, grazing along the mud surface ingesting diatoms or small plant debris. In habitats with boulders on mud, the snail has been observed grazing diatoms and other periphyton (sessile organisms that live attached to rocky surfaces) and aquatic plants.
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Florissant is significant in that it is one of the earliest known examples of freshwater diatoms.
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Stauroneis is a genus of diatoms (Bacillariophyta) with species that occur in fresh and marine water.
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Eucampia is a genus of marine centric diatoms. It was first described by Ehrenberg in 1839.
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His major areas of research include the taxonomy of planktonic algae, haptophytes, toxic diatoms and raphidophytes.
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When using diatom testing, scientists observe the amount of diatoms present on the organism and may be able to estimate a generalized time of death. If there are less than 20 different species of colonizing diatoms, then the organism's death could have been within the previous 7 to 12 days, but, if there are more than 50 different colonies of diatoms then it is determined that death possibly occurred several weeks ago. Certain taxa of diatoms narrow the time frame to more exact dates. For example, Ankistrodesmus algae is a type of diatom that does not start to colonize on an organism till 30 days after its death.
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It digests the minute life forms stuck to them, such as diatoms, bryozoans, amphipods, and polychaetes.Blaber, S.J.M. (2008): Tropical Estuarine Fishes: Ecology, Exploration and Conservation. John Wiley & Sons. pg. 113. Diatoms, for example may make up 50% of the dry weight of the matter the fish consumes.
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The physiological distribution, fixation, and recycling center for inorganic carbon and nitrogen plays a key role in the metabolic response of diatoms to prolonged nutrient deprivation. The cycle enables diatoms to respond immediately to the availability of nutrients and recover by increasing their metabolic and growth rates.
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Diatoms are diverse microscopic algae with silica cell walls that have different characteristics such as color, shape, and size. There are 8,000 known species of diatoms (without taking into account the variety of subspecies that have specialized within their specific environments). Diatoms do not have specialized nutrient and water conducting tissues, which affects their dispersion throughout ecosystems. These microscopic organisms mainly inhabit freshwater environments because of their inability to survive with the cleaning agents present in domestic water sources.
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Without the inhalation of water and some circulation present in the victim, the diatoms will not be able to enter the alveolar system and blood stream making it difficult to extract a reliable sample. Another issue with the use of diatoms in order to provide evidential support is that diatoms can also be found on clothes, in food and drink, or air. In a study conducted by Spitz and Schneider in 1964, 500 cubic meters of air was filtered for three days in April and there was between 662 and 1564 individual diatoms present on the filtrate. Because the body can preserve these microscopic algae, the presence of diatoms may not only be on a victim or suspect through their relation to a crime scene, which affects the reliability of the results collected from a scene.
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In: Tomas, C.R. (Ed.), Identifying Marine Diatoms and Dinoflagellates. Academic Press, San Diego (California), pp. 387–583.).
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Within a day, the diatoms will come to the top in a scum and can be isolated.
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Since diatoms do not appear at this time, the authors contribute these abnormally high levels to dinoflagellates.
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Burkhardt Steffen, Amoroso Gabi, Riebesell Ulf, Sültemeyer Dieter, (2001), CO2 and HCO3 ߚ uptake in marine diatoms acclimated to different CO2 concentrations, Limnology and Oceanography, 6, . Large diatoms require more carbon uptake than smaller diatoms.Brian N. Popp, Edward A. Laws, Robert R. Bidigare, John E. Dore, et al.
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Pennate diatoms are bilaterally symmetric. Each one of their valves have openings that are slits along the raphes and their shells are typically elongated parallel to these raphes. They generate cell movement through cytoplasm that streams along the raphes, always moving along solid surfaces. Centric diatoms are radially symmetric.
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Similar to plants, diatoms convert light energy to chemical energy by photosynthesis, although this shared autotrophy evolved independently in both lineages. Unusually for autotrophic organisms, diatoms possess a urea cycle, a feature that they share with animals, although this cycle is used to different metabolic ends in diatoms. The family Rhopalodiaceae also possess a cyanobacterial endosymbiont called a spheroid body. This endosymbiont has lost its photosynthetic properties, but has kept its ability to perform nitrogen fixation, allowing the diatom to fix atmospheric nitrogen.
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Diatoms are generally 2 to 200 micrometers in size, with a few larger species. Their yellowish-brown chloroplasts, the site of photosynthesis, are typical of heterokonts, having four membranes and containing pigments such as the carotenoid fucoxanthin. Individuals usually lack flagella, but they are present in male gametes of the centric diatoms and have the usual heterokont structure, including the hairs (mastigonemes) characteristic in other groups. Diatoms are often referred as "jewels of the sea" or "living opals" due to their optical properties.
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Forensic scientists can create differentiated markers on environments in the area they are collecting data based on the diatoms population growth rate, which is affected by pollutants in their water sources because the simple tissues of diatoms make them sensitive environmental changes. The reason diatoms are a common tool to match water environments is because of the variability of their populations are predictable and constant, the organisms can be identified by using the light microscope, and their silica cell walls allow for preservation.
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Copepods are known to be the primary consumers of diatoms in the water column and initiate the production of PUA upon grazing. The consumption of PUA- producing diatoms by copepods has been shown to diminish their reproductive success. Specifically, female copepods that consume diatoms spawn eggs with low viabilities and offspring with high teratogenesis rates. The compounds mainly act by preventing cell division and promoting apoptosis in copepod embryos,Miralto A, Barone G, Romano G, Poulet S, Ianora A, et al.
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Silicates are particularly common in marine biominerals, where Diatoms and Radiolaria form frustules from hydrated amorphous silica (Opal).
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Cymatosira is a genus of diatoms in the family Cymatosiraceae. It is the type genus of its family.
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Asterionella is a genus of pennate freshwater diatoms. They are frequently found in star-shaped colonies of individuals.
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The earliest known fossil diatoms date from the early Jurassic (~185 Ma ago), although the molecular clock and sedimentary evidence suggests an earlier origin. It has been suggested that their origin may be related to the end-Permian mass extinction (~250 Ma), after which many marine niches were opened. The gap between this event and the time that fossil diatoms first appear may indicate a period when diatoms were unsilicified and their evolution was cryptic. Since the advent of silicification, diatoms have made a significant impression on the fossil record, with major fossil deposits found as far back as the early Cretaceous, and with some rocks such as diatomaceous earth, being composed almost entirely of them.
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Johannes Boye Petersen (September 29, 1887 – March 22, 1961) was a Danish botanist and phycologist, mainly working on diatoms.
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Today & Tomorrow's Publishers, New Delhi. # Gandhi, H. P. 1998. Freshwater Diatoms of Central Gujarat. Bishen Singh Mahendra Pal Singh.
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This fish eats primarily aquatic insects, some terrestrial insects, fish eggs, algae and diatoms. Prey are located by sight.
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Craspedodiscus elegans is a species of diatoms in the genus Craspedodiscus. It is the type-species in the genus.
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The imaged region measures approximately 1.13 by 0.69 mm. Living organisms also contribute to this geologic cycle. For example, a type of plankton known as diatoms construct their exoskeletons ("frustules") from silica extracted from seawater. The frustules of dead diatoms are a major constituent of deep ocean sediment, and of diatomaceous earth.
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Salinity is a more challenging quantity to infer from paleorecords. Deuterium excess in core records can provide a better inference of sea-surface salinity than oxygen isotopes, and certain species, such as diatoms, can provide a semiquantitative salinity record due to the relative abundances of diatoms that are limited to certain salinity regimes.
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Thalassiosiraceae is a family of diatoms in the order Thalassiosirales. The family of Thalassiosiraceae have the unique quality of having a flat valve face. These diatoms are common in brackish, nearshore, and open-ocean habitats, with approximately the same number of freshwater and marine species. Thalassiosiraceae are a centric diatom full of fultoportula.
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Many species of diatoms are used for synthesizing nanoparticles and are being explored for their use as drug delivery systems.
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Marine algae have traditionally been placed in groups such as: green algae, red algae, brown algae, diatoms, coccolithophores and dinoflagellates.
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"The biomass and total lipid content and composition of twelve species of marine diatoms cultured under various environments", Food Chemistry.
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Algae such as diatoms, along with other phytoplankton, are photosynthetic primary producers supporting the food web of the Great Lakes, and have been effected by global warming. The changes in the size or in the function of the primary producers may have a direct or an indirect impact on the food web. Photosynthesis carried out by diatoms comprises about one fifth of the total photosynthesis. By taking out of the water, to photosynthesize, diatoms help to stabilize the pH of the water, as otherwise would react with water making it more acidic. :CO2 + H2O <=> HCO3^- + H+ Diatoms acquire inorganic carbon thought passive diffusion of and HCO3, as well they use carbonic anhydrase mediated active transport to speed up this process.
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It is used as a feedstock for production of some phosphors and semiconductor materials. Germanium dioxide is used in algaculture as an inhibitor of unwanted diatom growth in algal cultures, since contamination with the comparatively fast-growing diatoms often inhibits the growth of or outcompetes the original algae strains. GeO2 is readily taken up by diatoms and leads to silicon being substituted by germanium in biochemical processes within the diatoms, causing a significant reduction of the diatoms' growth rate or even their complete elimination, with little effect on non-diatom algal species. For this application, the concentration of germanium dioxide typically used in the culture medium is between 1 and 10 mg/l, depending on the stage of the contamination and the species.
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The flagella ensnare food particles which are then engulfed. These cells often contain symbiotic diatoms, minute photosynthetic algae. These use carbohydrates manufactured by the sponge but also create sugars by photosynthesis when there is sufficient light. These diatoms benefit from the protection the sponge provides which enhances their prospects for survival in the Antarctic winter.
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Pseudo-nitzschia species are bilaterally symmetrical Pennate diatoms. Cell walls are made up of elongated silica frustules. The silica wall is fairly dense which leads to negative buoyancy, providing a number of advantages. The wall allows the diatoms to sink to avoid light inhibition or nutrient limitations, as well as to protect against grazing zooplankton.
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Diatoms can also be used to study oxygen isotopes and are especially useful in regions of the ocean where foraminifera do not preserve in marine sediments. One example of vital effects in diatoms is a difference in δ18O between two different species, Coscinodiscus marginatus and Coscinodiscus radiatus, which is attributed to their difference in size.
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Riedelia is a genus of diatoms known from the fossil record, comprising approximately eight species. Many of the species were originally described under the closely allied genus Hemiaulus. Paleontologists Hans-Joachim Schrader and Juliane Fenner, working with fossil specimens obtained from Leg 38 of the Deep Sea Drilling Program in the Norwegian and Greenland Seas, decided that several previous descriptions of diatoms belonging to Hemiaulus were rightfully placed on Riedelia. Schrader and Fenner note that while Hemiaulus diatoms have polygonal areolated valves, Riedelia valves are punctate with isolated punctae.
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A contribution to our knowledge of the freshwater Diatoms of Pratapgarh, Rajasthan. Journal of the Indian Botanical Society 34: 304–338.
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In simple terms, palynology is the study of pollen. Pollen have specific shapes, so the species is easily identifiable and can provide a record of environmental change and pollen dating. Diatoms are microscopic single celled plants that can be found in or near water. By studying diatoms, changes such as deforestation and pollution can be determined.
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Unlike most diatoms P. tricornutum can grow in the absence of silicon, and it can survive without making silicified frustules. This provides opportunities for experimental exploration of silicon-based nanofabrication in diatoms. Another peculiarity is that during asexual reproduction the frustules do not appear to become smaller. This allows continuous culture without need for sexual reproduction.
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They comprise an integral component of the periphyton community. Another classification divides plankton into eight types based on size: in this scheme, diatoms are classed as microalgae. Several systems for classifying the individual diatom species exist. Fossil evidence suggests that diatoms originated during or before the early Jurassic period, which was about 150 to 200 million years ago.
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The species is herbivorous, feeding only on diatoms and filamentous algae, and vigorously defending its feeding patch. The fish cultivate gardens on the upper surfaces of stones and boulders. Here they encourage a short turf of diatoms, filamentous algae and blue-green algae. The males guard these territorial gardens and they play a part in courtship.
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However, these abundances are still under the guidelines and its unclear if this is solely related to river regulation, but also reflects other catchment inputs. The composition of algae in the free flowing snow melt rivers are typically defined by diatoms. Over 58% of taxa are diatoms, with Fragilaria spp. being the most numerically abundant taxa.
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Ruth Patrick was the daughter of Frank Patrick, a banker, and lawyer. Frank had a degree in botany from Cornell University in Ithaca, New York, and was a hobbyist scientist. He often took Ruth and her sister on Sunday afternoons to collect specimens, especially diatoms, from streams. This sparked a lifelong interest in diatoms and ecology.
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Actinocyclus normanii fo. subsalsa (Juhlin-Dannfelt) Hustedt, 1957 USGS. Retrieved 2011-11-18.Actinocyclus normanii Ehrenberg(1837) River diatoms: a multiaccess key.
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In microbiology and planktology, a theca is a subcellular structural component out of which the frustules of diatoms and dinoflagellates are constructed.
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Corinna is an extinct genus of diatoms of uncertain placement within Bacillariophyceae (incertae sedis). C. elegans is from the Cretaceous of Canada.
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The delta class of CAs has been described in diatoms. The distinction of this class of CA has recently come into question, however.
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Biomphalaria glabrata feeds on bacterial films, algae, diatoms and decaying macrophytes.What is Biomphalaria glabrata? UNM Biology Department Home Page. Accessed 20 November 2009.
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Diatoms contribute in a significant way to the modern oceanic silicon cycle: they are the source of the vast majority of biological production.
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A systematic account of the Diatoms of Bombay and Salsette – III. Journal of the Indian Botanical Society 33: 338–350. # Gandhi, H.P. 1955.
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Oreochromis lidole feeds mainly on plankton- including crustaceans, such as Bosmina and Diaptomus, diatoms such as Aulacoseira and Surirella and other larger algae.
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In diatomaceous earth filters, a natural powderlike material composed of the shells of microscopic organisms called diatoms is used as a filter media.
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For many years the diatoms—treated either as a class (Bacillariophyceae) or a phylum (Bacillariophyta)—were divided into just 2 orders, corresponding to the centric and the pennate diatoms (Centrales and Pennales). This classification was extensively overhauled by Round, Crawford and Mann in 1990 who treated the diatoms at a higher rank (division, corresponding to phylum in zoological classification), and promoted the major classification units to classes, maintaining the centric diatoms as a single class Coscinodiscophyceae, but splitting the former pennate diatoms into 2 separate classes, Fragilariophyceae and Bacillariophyceae (the latter older name retained but with an emended definition), between them encompassing 45 orders, the majority of them new. Today (writing at mid 2020) it is recognised that the 1990 system of Round et al. is in need of revision with the advent of newer molecular work, however the best system to replace it is unclear, and current systems in widespread use such as AlgaeBase, the World Register of Marine Species and its contributing database DiatomBase, and the system for "all life" represented in Ruggiero et al.
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MRK graduated with a Master of Arts in Communication Design from Central St. Martins in 2007 and is currently working as a creative director, motion designer and lecturer. "Jotta:Markos Kay" In 2008, MRK released “aDiatomea,” an experimental piece that simulates diatoms consisting of realistic 3d generated diatoms. "Algorithmic Worlds" Each variant of these mathematical creatures is classified in actual taxonomies, giving Victorian diatom art a 21st-century redux. "Okological: aDiatomea" Granular sound is 'injected' into the diatoms affecting their form and movement, creating a dynamic system. "Dataisnature" In 2012, "aDiatomea" was part of the official selection at Imagine Science Films in New York.
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Diatom DNA barcoding is a method for taxonomical identification of diatoms even to species level. It is conducted using DNA or RNA followed by amplification and sequencing of specific, conserved regions in the diatom genome followed by taxonomic assignment. One of the main challenges of identifying diatoms is that it is often collected as a mixture of diatoms from several species. DNA metabarcoding is the process of identifying the individual species from a mixed sample of environmental DNA (also called eDNA) which is DNA extracted straight from the environment such as in soil or water samples.
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Living diatoms are often found clinging in great numbers to filamentous algae, or forming gelatinous masses on various submerged plants. Cladophora is frequently covered with Cocconeis, an elliptically shaped diatom; Vaucheria is often covered with small forms. Since diatoms form an important part of the food of molluscs, tunicates, and fishes, the alimentary tracts of these animals often yield forms that are not easily secured in other ways. Diatoms can be made to emerge by filling a jar with water and mud, wrapping it in black paper and letting direct sunlight fall on the surface of the water.
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The main goal of diatom analysis in forensics is to differentiate a death by submersion from a post-mortem immersion of a body in water. Laboratory tests may reveal the presence of diatoms in the body. Since the silica-based skeletons of diatoms do not readily decay, they can sometimes be detected even in heavily decomposed bodies. As they do not occur naturally in the body, if laboratory tests show diatoms in the corpse that are of the same species found in the water where the body was recovered, then it may be good evidence of drowning as the cause of death.
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Skeletonema is a genus of diatoms in the family Skeletonemataceae. It is the type genus of its family. The genus Skeletonema was established by R.K. Greville in 1865 for a single species, S. barbadense, found in the Barbados deposit [Jung 2009]. These diatoms are photosynthetic organisms, meaning they obtain carbon dioxide from their surrounding environment and produce oxygen along with other byproducts.
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Furthermore, most existing metabarcoding data are only locally available and geographically scattered, which is hindering the development of globally useful tools. Visco et al. estimated that no more than 30% of European diatoms species are currently represented in reference databases. For example, there is an important lack for a number of species from the Fennoscandian communities (especially acidophilic diatoms, such as Eunotia incisa).
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Publishers, Fourth edition, 764 pp In diatoms and dinoflagellates, the xanthophyll cycle consists of the pigment diadinoxanthin, which is transformed into diatoxanthin (diatoms) or dinoxanthin (dinoflagellates) under high-light conditions.Jeffrey, S. W. & M. Vesk, 1997. Introduction to marine phytoplankton and their pigment signatures. In Jeffrey, S. W., R. F. C. Mantoura & S. W. Wright (eds.), Phytoplankton pigments in oceanography, pp 37-84.
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Diatoms have varied life strategies including floating in the water column (phytoplankton), colonising submerged surfaces and living within the surface of deposited sediments. Some cells are essentially cylindrical (centric) while others have an elongated "boat-like" shape. Since they are algae belonging to the division Bacillariophyta they require light for photosynthesis. Perhaps the most studied group of diatoms belong to the phytoplankton.
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It is mainly herbivorous, feeding on algae and diatoms. Breeding takes place in late spring and early summer in gravelly riffles in small streams.
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Lake BaikalYelena V. Likhoshway et al., “The Distribution of Diatoms Near a Thermal Bar in Lake Baikal,” Journal of Great Lakes Research 22, no.
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This species needs clean, oxygen-rich rivers. These snails live on hard benthic substrates, typically rocks or stony ground and feed mainly on diatoms.
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Tarebia granifera feeds on algae, diatoms and detritus. A scanning electron microscopic image of an apertural view of a newborn shell of Tarebia granifera.
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Vital effects are biological impacts on geochemical records. Many marine organisms, ranging from zooplankton (e.g. foraminifera) to phytoplankton (e.g diatoms) to reef builders (e.g.
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This has the potential to decrease the future population of copepods and promote the survival of copepods which do not eat as many diatoms.
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Diatoms can also be destroyed based on the biological make up of the body it encounters, this could affect the results in a criminal investigation.
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Underwater vegetation does not occur in Laguna Socompa owing to the brackish water. There is little phytoplankton in the lake waters, mainly cyanobacteria and diatoms.
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The shell of an adult Jagora asperata can be as long as . These freshwater snails mainly feed on blue-green algae, diatoms and organic debris.
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Fertilization appears to be external. The larvae development are leicithotrophic and dermersal. When the larvae reach about 180μm long they start to feed on diatoms.
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Marine diatoms form hard silicate shells Plant-like diatoms and animal-like radiolarians are two forms of plankton which form hard silicate shells. Foraminifera and coccolithophores create shells known as "tests" which are made of calcium carbonate. These shells and tests are usually microscopic in size, though in the case of foraminifera, they are sometimes visible to the naked eye, often resembling miniature mollusk shells.
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Selva attended Humboldt State University in Arcata, California, earning bachelor's degrees in biology and botany. He continued his education at Iowa State University in Ames where he earned his PhD in botany. His dissertation focused on establishing biostratigraphic units based on freshwater diatoms preserved in the soil of the Ogallala Aquifer. During the course of his research, Selva discovered seven new species of diatoms.
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Showing the major fluxes of silicon. Most biogenic silica in the ocean (silica produced by biological activity) comes from diatoms. Diatoms extract dissolved silicic acid from surface waters as they grow, and return it to the water column when they die. Inputs of silicon arrive from above via aeolian dust, from the coasts via rivers, and from below via seafloor sediment recycling, weathering, and hydrothermal activity.
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Diatomaceous earth as viewed under bright field illumination on a light microscope. This image consists of a mixture of centric (radially symmetric) and pennate (bilaterally symmetric) diatoms suspended in water. The scale is 6.236 pixels/μm, the image is 1.13 by 0.69 mm. Diatoms, and their shells (frustules) as diatomite or diatomaceous earth, are important industrial resources used for fine polishing and liquid filtration.
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The sponge reefs declined throughout the Cretaceous period as coral and rudist reefs were becoming prominent. It is theorized that the spread of diatoms may have been detrimental to the sponges, as diatoms compete with hexactinellid sponges for silica. It is estimated through radiocarbon dating of reef cores that the reefs have been living on the continental shelf of Western Canada for 8500–9000 years.
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The prime interest of paleobotany is to reconstruct the vegetation that people in the past would have encountered in a particular place and time. Plant studies have always been overshadowed by faunal studies because bones are more conspicuous than plant remains when excavating. Collection of plant remains could everything including pollen, soil, diatoms, wood, plant remains and phytoliths. Phytoliths are sediments and diatoms are water deposits.
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Fragilaria is a genus of freshwater and saltwater diatoms. It is usually a colonial diatom, forming filaments of cells mechanically joined by protrusions on the face and in the center of their valves. The individual diatoms appear swollen in their centers where they are joined to the colonial ribbon. the genus grows as both plankton and benthic species, free living in colonies or epiphytic.
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Mud shrimp activity has also been shown to increase the movement of carbon and dissolved inorganic nitrogen in and out of the mud. Some species of diatoms, a type of phytoplankton, can be found on the sediments of Yaquina Bay wetlands. These diatoms are also important in nutrient cycling within the estuary. Another type of estuary habitat is formed by native Olympia oysters (Ostrea lurida).
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Diatoms are routinely used as part of a suite of biomonitoring tools which must be monitored as part of the European Water Framework Directive. Diatoms are used as an indicator of ecosystem health in freshwaters because they are ubiquitous, directly affected by the changes in physico-chemical parameters and show a better relationship with environmental variables than other taxa e.g. invertebrates, giving a better overall picture of water quality.300x300px Over the recent years, researchers have developed and standardised the tools for the metabarcoding and sequencing of diatoms, to complement the traditional assessment using microscopy, opening up a new avenue of biomonitoring for aquatic systems.
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Diatoms are mainly photosynthetic; however a few are obligate heterotrophs and can live in the absence of light provided an appropriate organic carbon source is available.
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Arca zebra is a filter feeder, taking in surrounding water and particulates through its reduced siphons and expelling water while consuming microscopic algae, diatoms, and phytoplankton.
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The most studied species of the genus, C. meneghiniana, has a diameter of 6-18 μm. Like all other diatoms, Cyclotella spp. have transparent cell walls.
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Interesting algae has been found, including 11 species of cyanobacteria, 156 species of diatoms (including varieties), 58 species of green algae and other species of algae.
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Chytrid parasites of marine diatoms. (A) Chytrid sporangia on Pleurosigma sp. The white arrow indicates the operculate discharge pore. (B) Rhizoids (white arrow) extending into diatom host.
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These fish prefer to feed on aquatic insects, algae, diatoms, aquatic insect larvae, and small crustaceans called entomostracans. Occasionally they will eat fish eggs or small fish.
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"Lipid and Fatty Acid Composition of Diatoms Revisited: Rapid Wound-Activated Change of Food Quality Parameters Influences Herbivorous Copepod Reproductive Success." ChemBioChem 8.10 (2007): 1146-153. Web.
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Foraminiferans are abundant around the reefs, and diatoms are scarce. The consortium of organisms living in and around sponge reefs has changed very little since the Jurassic.
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Cleve's early research, in 1895 and 1896, included studies of diatoms in the high-altitude lakes in the Lule Lappmark region. She published work identifying and drawing newly discovered diatoms from Arctic lakes. She also surveyed the plant ecosystems in the far north regions and their adaptations to the harsh environment. Between 1896 and 1898, Cleve published four chemistry papers, all of which concerned nitrogenous organic chemicals in varying structures.
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The gut of E. superba can often be seen shining green through its transparent skin. This species feeds predominantly on phytoplankton—especially very small diatoms (20 μm), which it filters from the water with a feeding basket. The glass-like shells of the diatoms are cracked in the "gastric mill" and then digested in the hepatopancreas. The krill can also catch and eat copepods, amphipods and other small zooplankton.
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Current Trends in Geology, Vol. VI (Climate and Geology of Kashmir) 6:57—60. # Gandhi, H. P., A B. Vora & D. J. Mohan, 1983. Fossil diatoms from Baltal, Karewa beds of Kashmir. Current Trends in Geology, Vol. VI (Climate and Geology of Kashmir) 6:61—68. # Gandhi, H. P., A B. Vora & D. J. Mohan, 1986. Ecology of diatoms from the Karewa beds of Baltal area, Kashmir, India.
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In turn, the shape of a diatom is determined by its species. Many deposits throughout British Columbia, such as Red Lake Earth, are from the Miocene epoch and contain a species of diatom known as Melosira granulata. These diatoms are approximately 12 to 13 million years old and have a small globular shape. A deposit containing diatoms from this epoch can provide many more benefits than that of an older deposit.
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The natural diet of anemonefish includes zooplankton, (diatoms and copepods), benthic worms, tunicates, and algae. A. perideraion is the only species of anemonefish to primarily feed on algae.
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Biddulphiophycidae or Biddulphiineae is a grouping of Centrales. In some taxonomic schemes Centrales or Centric diatoms are named Coscinodiscophyceae and may have different naming of suborders and families.
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II. Nova Hedwigia 3: 469–505. # Gandhi, H.P. 1962. Some freshwater diatoms from Lonawala Hill Station in the Bombay State (Maharashtra). Hydrobiologia 20: 128–154. # Gandhi, H.P. 1962.
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Ditylum brightwelli is a species of cosmopolitan marine centric diatoms. It is a unicellular photosynthetic autotroph that has the ability to divide rapidly and contribute to spring phytoplankton blooms.
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Ceylon Journal of Science (Biology Section) 2: 98—116. # Gandhi, H.P., 1959. Freshwater diatoms from Sagar in the Mysore State. Journal of the Indian Botanical Society 38: 305–331.
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Fragilaria gracilis is a species of freshwater pennate diatoms. F. gracilis is reported from many parts of Europe, in Sweden even as one of the dominant freshwater diatom taxa.
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Attheya gaussii is a species of diatoms in the genus Attheya.R.M. Crawford, F. Hinz, & P. Koschinski. 2000. The combination of Chaetoceros gaussii (Bacillariophyta) with Attheya. Phycologia 39: 241. 2000.
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Rhopalodia gibba, a diatom alga, is a eukaryote with cyanobacterial -fixing endosymbiont organelles. The spheroid bodies reside in the cytoplasm of the diatoms and are inseparable from their hosts.
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This is more often observed in freshwater and pennate diatoms like Pseudo- nitzschia. There is contradictory evidence regarding the presence or absence of a resting stage in Pseudo-nitzschia.
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In 1867, the Swede Alfred Nobel discovered that infusorial earth, diatomaceous earth from fossil deposits of diatoms, absorbed nitroglycerine, thereby inhibiting the tendency of this explosive to detonate spontaneously.
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Diatoms belong to a large group called the heterokonts, which include both autotrophs such as golden algae and kelp; and heterotrophs such as water moulds. The classification of heterokonts is still unsettled: they may be designated a division, phylum, kingdom, or something intermediate to those. Consequently, diatoms are ranked anywhere from a class, usually called Diatomophyceae or Bacillariophyceae, to a division (=phylum), usually called Bacillariophyta, with corresponding changes in the ranks of their subgroups.
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Diatoms need, among other nutrients, silicic acid to create biogenic silica for their frustules (cell walls). As a result of this, the Redfield-Brzezinski nutrient ratio was proposed for diatoms and stated to be C:Si:N:P = 106:15:16:1. Extending beyond primary production itself, the oxygen consumed by aerobic respiration of phytoplankton biomass has also been shown to follow a predictable proportion to other elements. The O2:C ratio has been measured at 138:106.
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The sizes of the diatoms associated with this size filtering apparatus are about 21-60 μm. Diatoms this size are typically found close to the edge of the water; even in colonies of multiple species, James's flamingos typically feed in the region closest to the edge of the water. The birds are able to use their webbed feet to help kick up microscopic algae if not enough are floating in the water column.
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P. newmani is mainly herbivorous, and feeds continuously, with an increased intake during the night. It prefers centric diatoms, even though aldehydes of the diatom genus Thalassiosira, for example, can be toxic to its young in large quantities. This is seen in the reduced reproductive success (both in terms of hatching success and naupliar viability) of P. newmani fed exclusively diatoms in the laboratory, and the reduced success of this copepod during Thalassiosira blooms.
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A number of microscopic algae also occur as symbionts in lichens. Phycologists typically focus on either freshwater or ocean algae, and further within those areas, either diatoms or soft algae.
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Attheya longicornis is a species of diatoms in the genus Attheya. Type material was collected from Penberth, Cornwall in England.Crawford, R. M., Gardner, C., Medlin, L. K. 1994. The genus Attheya.
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Fossil diatoms from Baltal, Kashmir. Man & Environment 7: 154–156. # Gandhi, H. P., A B. Vora & D. J. Mohan, 1983. Review of the fossil Diatomflora, of the Karewa Beds of Kashmir.
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Parborlasia corrugatus is both a scavenger and a predator, and feeds upon detritus diatoms, gastropods, amphipods, isopods, various vertebrate carrion, sponges (including Homaxinella balfourensis), jellyfish, seastars, molluscs, anemones, and polychaete worms.
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Phytoplanktonic diatoms rely on ocean currents and wind to keep them in the upper oceanic levels as their cell wall is denser than water around them. They would naturally sink otherwise.
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Mummichogs are omnivorous. Analyses of their stomach contents have found diatoms, amphipods and other crustaceans, molluscs, fish eggs (including their own species), very small fish, insect larvae, and bits of eelgrass.
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Diatoms are ecologically successful, and occur in virtually every environment that contains water – not only oceans, seas, lakes, and streams, but also soil and wetlands. The use of silicon by diatoms is believed by many researchers to be the key to this ecological success. Raven (1983) noted that, relative to organic cell walls, silica frustules require less energy to synthesize (approximately 8% of a comparable organic wall), potentially a significant saving on the overall cell energy budget. In a now classic study, Egge and Aksnes (1992) found that diatom dominance of mesocosm communities was directly related to the availability of silicic acid – when concentrations were greater than 2 µmol m−3, they found that diatoms typically represented more than 70% of the phytoplankton community.
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The lake was deep enough for the development of planktonic diatoms, including the dominant Cyclotella choctawatcheeana. Other diatoms noted in Lake Tauca are the benthic Denticula subtilis, the epiphytic Achnanthes brevipes, Cocconeis placentula and Rhopalodia gibberula, the planktonic Cyclotella striata and the tychoplanktonic Fragilaria atomus, Fragilaria construens and Fragilaria pinnata. Epithemia has also been found. Sediments at the shoreline contain fossils of gastropods and ostracods; Littoridina and Succineidae snails have been used to date the lake.
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The oldest fossil evidence for diatoms is a specimen of extant genus Hemiaulus in Late Jurassic aged amber from Thailand. Diatoms are used to monitor past and present environmental conditions, and are commonly used in studies of water quality. Diatomaceous earth (diatomite) is a collection of diatom shells found in the earth's crust. They are soft, silica- containing sedimentary rocks which are easily crumbled into a fine powder and typically have a particle size of 10 to 200 μm.
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When a body has been drowned diatoms go into the lungs and then are circulated to other internal organs through the individuals circulation. A forensic scientist will extract 100 g of either a tissue sample or bone marrow from a femur still attached to the victim. There are many different methods of extracting diatoms but the most commonly used method is acid digestion. This method is acknowledged worldwide, less expensive, and takes less time to get results.
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In certain species of diatoms, auxospores are specialised cells that are produced at key stages in their cell cycle or life history. Auxospores typically play a role in growth processes, sexual reproduction or dormancy.Hoek, C. van den, Mann, D. G. and Jahns, H. M. (1995). Algae : An introduction to phycology, Cambridge University Press, UK. Auxospores are involved in re-establishing the normal size in diatoms because successive mitotic cell divisions leads to a decrease in cell size.
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With more than 100 alga species, the Loire has the highest phytoplankton diversity among French rivers. The most abundant are diatoms and green algae (about 15% by mass) which mostly occur in the lower reaches. Their total mass is low when the river flow exceeds and become significant at flows of or lower which occur in summer. With decreasing flow, first species which appear are single-celled diatoms such as Cyclostephanos invisitatus, C. meneghiniana, S. Hantzschii and Thalassiosira pseudonana.
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The cell wall and cell membrane are what are known to this point as what distinguishes Cyclotella from other diatom genera. The cytoplasmic components are assumed to be similar to what other diatoms have. In C. meneghiniana, there are granules scattered and attached at the chromatophore all throughout the cytoplasm. The genus is photosynthetic like all other diatoms, so all species contain one or many pyrenoids traversed by a thylakoid membrane and a chloroplast within the endoplasmic reticulum.
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The nanoplankton response is negligible. The enhanced productivity of diatoms (microplankton) is small. The subtle phytoplankton increase of the baseline OTEC plant suggests that higher-order biochemical effects will be very small.
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Cladogramma is an extinct genus of prehistoric marine diatoms with uncertain affinity. Species are known from the Pliocene of Japan, Miocene of the United States (North Carolina), Cretaceous and Paleocene of Antarctica.
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Larval yelloweye feed on diatoms, dinoflagellates, crustaceans, tintinnids, and cladocerans, and juveniles consume copepods and euphausiids of all life stages. Adults eat demersal invertebrates and small fishes, including other species of rockfish.
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Tabellaria is a genus of freshwater diatoms (Bacillariophyta). They are cuboid in shape, and the frustules (siliceous cell walls) are attached at the corners so that the colonies assume a zigzag shape.
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Certain species of bacteria in oceans and lakes can accelerate the rate of dissolution of silica in dead and living diatoms by using hydrolytic enzymes to break down the organic algal material.
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Some common freshwater diatoms from Gersoppa-falls (Jog-Falls). Journal of the Poona University, Science Section 12: 13–21. # Gandhi, H.P. 1957. A contribution to our knowledge of the diatom genus Pinnularia.
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Certain species of bacteria in oceans and lakes can accelerate the rate of dissolution of silica in dead and living diatoms; by using hydrolytic enzymes to break down the organic algal material.
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Some species are bloom forming diatoms in eutrophic lakes. The type species is Fragilaria pectinalis Lyngbye from designating a lectotype from Conferva pectinalis O.F.Müller. The taxonomy of the genus is still uncertain.
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Marine Diatoms. In: Tomas, C.R. (Ed.) Identifying Marine Phytoplankton. Academic Press. Species that are most commonly found in marine environments are C. caspia, C. litoralis, C. meneghiniana, C. striata, and C. stylorwn.
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Juvenile minnows may also eat rotifers, nematodes, diatoms, and algae. The fish lives in slow-moving and stagnant waters in muddy and sandy well-vegetated habitat types where there are hiding spots.
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Golden skiffia's numbers were dramatically reduced within a year, likely due to competition from X. maculatus. Golden skiffia is likely a benthic feeder, as indicated by gut contents dominated by pennate diatoms.
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Coscinodiscophycidae or Coscinodiscineae is a grouping of Coscinodiscophyceae, previously known as "Centrales", a paraphyletic order of centric diatoms, a major group of algae and one of the most common members of the phytoplankton.
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Colonies of Trichodesmium provide a pseudobenthic substrate for many small oceanic organisms including bacteria, diatoms, dinoflagellates, protozoa, and copepods (which are its primary predator); in this way, the genus can support complex microenvironments.
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Round, F. E., Crawford, R. M., Mann, D. G., (1990). The Diatoms, Biology and Morphology of the Genera, pp. 747. Cambridge University Press. The taxonomic status of this family is unclear and disputed.
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Dr. Max Bothwell at Environment Canada claims that phosphorus-poor streams create blooms of the algae. The research paper, "Blooms of benthic diatoms in phosphorus-poor streams" was first published in March 2017.
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Bacillarnavirus is a genus of viruses in the order Picornavirales. Marine diatoms serve as natural hosts. There are currently three species in this genus, including the type species Rhizosolenia setigera RNA virus 01.
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That same year, Cleve published on the Quaternary geology of the region. In this same period, she was employed by geologists of the Geological Survey of Sweden to study diatoms in postglacial sediment. She did not produce another major work until 1951, when her comprehensive monograph on Swedish and Finnish diatoms, written over more than a decade, was published. Still in use today, Die Diatomeen von Schweden und Finnland covered approximately 1600 diatom species and their taxonomy, distribution, ecology, and fossils.
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The photosynthetic pigments present in their chloroplasts give diatoms a greenish-brown color. The heterokontophytes, also known as the stramenopiles, are a very large and diverse group of eukaryotes. The photoautotrophic lineage, Ochrophyta, including the diatoms and the brown algae, golden algae, and yellow-green algae, also contains red algal derived chloroplasts. Heterokont chloroplasts are very similar to haptophyte chloroplasts, containing a pyrenoid, triplet thylakoids, and with some exceptions, having four layer plastidic envelope, the outermost epiplastid membrane connected to the endoplasmic reticulum.
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The bolidophyte form lacks silica plates and has two unequal flagella inserted ventrally, vaguely reminiscent of Chlamydomonas. The parmalean form is similar to the diatoms as it is coated in silicate plates. These silicate plates are used to divide the Parmales into separate genera based upon the number and location of the siliceous plates. Unlike the diatoms, the Parmales are able to grow in silica-limiting environments because the synthesis of the silica plates is not directly connected to growth or reproduction.
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Applying the DNA barcoding concept to diatoms promises great potential to resolve the problem of inaccurate species identification and thus facilitate analyses of the biodiversity of environmental samples. Molecular methods based on the NGS technology almost always leads to a higher number of identified taxa whose presence could subsequently be verified by light microscopy. Results of this study provides evidence that eDNA barcoding of diatoms is suitable for water quality assessment and could complement or improve traditional methods. Stoeck et al.
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In order to use diatom testing there are some guidelines that scientists must follow. To get a more accurate result there has to be at least 20 diatoms in a 100 microliter sample. When dealing with testing on a human body having 5 complete diatoms from more than 2 different organs will also give a positive diagnosis. Samples are taken from bone marrow, lung, spleen, liver, kidney, brain tissue, or from the area where the crime was discovered or occurred.
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The life history of diatoms includes both vegetative and sexual reproduction, though the sexual stage is not yet documented in this species. Although it is symmetric only along the apical axis, typical of gomphonemoid diatoms, it is a cymbelloid, which are typically symmetric along both primary axes. Cells contain a raphe, which allows them to move on surfaces, and an apical porefield, through which a mucopolysaccharide stalk is secreted. The stalk can attach to rocks, plants, or other submerged surfaces.
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During alveolar fluid exchange, diatoms present in the water may pass through the alveolar wall into the capillaries to be carried to internal organs. The presence of these diatoms may be diagnostic of drowning. Of people who have survived drowning, almost one-third will experience complications such as acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). ALI/ARDS can be triggered by pneumonia, sepsis, and water aspiration and are life-threatening disorders that can result in death if not treated promptly.
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The shells of dead diatoms can reach as much as a half-mile (800 m) deep on the ocean floor, and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by transatlantic winds from the African Sahara, much of it from the Bodélé Depression, which was once made up of a system of fresh-water lakes. Diatoms are unicellular: they occur either as solitary cells or in colonies, which can take the shape of ribbons, fans, zigzags, or stars. Individual cells range in size from 2 to 200 micrometers. In the presence of adequate nutrients and sunlight, an assemblage of living diatoms doubles approximately every 24 hours by asexual multiple fission; the maximum life span of individual cells is about six days.
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PGP Ltd. is a small farm in Southern Israel. It cultures marine fish, microalgae, bivalves and Artemia. Effluents from seabream and seabass collect in sedimentation ponds, where dense populations of microalgae --mostly diatoms--develop.
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Clepsydra is a genus of diatoms, including the species Clepsydra truganiniae. It was found in Tasmania.Vyverman, W.; Sabbe, K.; Mann, D.; Vyverman, R.; Hodgson, D.A.; Muylaert, K.; Vanhoutte, K. (1998). Clepsydra truganiniae gen. nov.
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Food inclusions contain bacteria, bluegreen algae, small dinoflagellates, diatoms, ciliates, and other dinoflagellates. Mechanisms of capture and ingestion in dinoflagellates are quite diverse. Several dinoflagellates, both thecate (e.g. Ceratium hirundinella, Peridinium globulus) and nonthecate (e.g.
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Their diet is varied by season and is made up of diatoms, insect larvae, and fish scales during the dry season while in the rainy season it is mainly insect larvae, filamentous algae, and ostracods.
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The DCM of clear, stratified water is commonly found below the epilimnion. Lake Superior is one of the world's largest freshwater lakes, and in the summer, its DCM ranges from approximately 20 m to 35 m below the surface. Although the epilimnion and DCM are neighbouring layers of water, the species composition of the epilimnion and the DCM differ almost entirely. These differences include the presence of less centric diatoms, more pennate diatoms, cryptophytes, and pyrrophytes at the DCM compared to the epilimnion layer.
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Hemipelagic sediments can be made of a diverse range of elements or mineral types. The composition of Hemipelagic sediment directly depends on the composition of the adjacent land mass and geologic events such as volcanism that influence sediment input into the ocean. Hemipelagic sediments are mainly terrigenous but can also have biological oozes from marine organisms like Radiolarians or Diatoms. Radiolarians are a species of zooplankton that produce silica tests, or shells and Diatoms are photosynthetic organisms that live in the sunlit region of the ocean.
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These structures demonstrated pores of sizes characteristic to diatom patterns. When T. pseudonana underwent genome analysis it was found that it encoded a urea cycle, including a higher number of polyamines than most genomes, as well as three distinct silica transport genes. In a phylogenetic study on silica transport genes from 8 diverse groups of diatoms, silica transport was found to generally group with species. This study also found structural differences between the silica transporters of pennate (bilateral symmetry) and centric (radial symmetry) diatoms.
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The Academy's Diatom Herbarium, the largest in the Americas and the second largest in the world, contains approximately 220,000 slides of these microscopic algae. The herbarium contains many specimens contributed by notable collectors, a diversity of fossil diatoms, and diatoms collected as part of numerous freshwater environmental surveys in the United States. The Diatom Herbarium also provides collections and taxonomic services for the Phycology Section of the Patrick Center for Environmental Research. Former curators of note include Charles S. Boyer, Ruth Patrick, and Charles Reimer.
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Because of their great diversity and specific ecological requirements, algae, particularly diatoms, make excellent indicators of water quality. Moreover, diatoms are readily preserved in sediments, which make them useful organisms for studying paleolimnology (the long-term trends of streams and lakes). The Phycology Section of the Patrick Center provides algal analyses for governmental and other agencies interested in both assessing water quality and long-term environmental trends. One such undertaking is the analyses of diatom assemblages in lake sediments (sediment cores) throughout the eastern United States.
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Attheya flexuosa is a species of diatoms in the genus Attheya. Type material was collected from Benllech, Gwynedd, North Wales in UK on intertidal sand.Crawford, R. M., Gardner, C., Medlin, L. K. 1994. The genus Attheya.
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Attheya decora is a species of diatoms in the genus Attheya. Type material was collected from Cresswell sands, Northumberland by Mr. Atthey.West, T. 1860. Remarks on some Diatomaceae, new or imperfectly described and a new Desmid.
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The Antarctic sea urchin largely feeds on diatoms and other algae. It also consumes foraminiferans, amphipods, bryozoans, hydrozoans, polychaete worms and sponges and also seal faeces when available.Antarctic sea urchin Underwater photography. Retrieved 2012-01-09.
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Navicula diatoms are known for their ability to creep about on each other and on hard surfaces such as microscope slides.Navicula Diatom: Youtube videoJ Microbiol Methods. 2013 Mar;92(3):349-54. doi: 10.1016/j.mimet.2013.01.006.
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Environmental threats such as heavy rainfall may also have an effect on the breeding of the species. Threats the productivity of the diatoms also threaten the species if enough food is available for them to eat.
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Cryptococcus laurentii and microalgae. Among microalgae, one of the main progenitors of biofilms are diatoms, which colonise both fresh and marine environments worldwide. For other species in disease-associated biofilms and biofilms arising from eukaryotes see below.
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Biofilm is the combination of algae, diatoms, fungi, bacteria, plankton, and other small microorganisms that exist in a film along the streambed or benthos. Biofilm assemblages themselves are complex, and add to the complexity of a streambed.
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Notes on the Diatomaceae from Ahmedabad and its environs- II. On the diatom flora of fountain reservoirs of the Victoria Gardens. Hydrobiologia 14: 130–146. # Gandhi, H.P. 1960. Some new diatoms from the Jog Falls, Mysore State.
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This herbivorous species lives on coral reef shore between algae and on dead corals, in the intertidal and shallow subtidal areas at a depth up to 10 m. It feeds on various species of algae and diatoms.
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Like most marine diatoms, C. pseudocurvisetus is characterized by its frustule, or cell wall, which is composed of silicon dioxide and other organic matter. The frustule forms as different sized valves, which overlap and are called thecae.
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Diatomite forms by the accumulation of the amorphous silica (opal, SiO2·nH2O) remains of dead diatoms (microscopic single-celled algae) in lacustrine or marine sediments. The fossil remains consist of a pair of symmetrical shells or frustules.
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Shirokawa, Y., Shimada, M. (2016). Cytoplasmic inheritance of parent–offspring cell structure in the clonal diatom Cyclotella meneghiniana. Proceedings of the Royal Society B. 283(1842). Like other monoraphid diatoms, Cyclotella frustules can be characterized as heterovalvar.
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The habitat types next to the tarn are 'single-species dominant swamp, acid-poor fen, acidic species- rich marshy grassland, hay meadow and wet woodland'. It was surveyed for diatoms in 1984 and 1999, the changes being consistent with the pH of the lake having increased. However, diatoms from sediment cores indicate a decrease in tarn pH from 6.3 to 5.8. Little Langdale Tarn was several times larger at the end of the last ice age, the lost area having become filled with sediment and resulted in the flat farmland beside the current lake.
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The latter approach is frequently employed by Chlorella farmers, as the growth conditions for Chlorella do not exclude competing algae. The former approach can be employed in the case of some chain diatoms since they can be filtered from a stream of water flowing through an outflow pipe. A "pillow case" of a fine mesh cloth is tied over the outflow pipe allowing other algae to escape. The chain diatoms are held in the bag and feed shrimp larvae (in Eastern hatcheries) and inoculate new tanks or ponds.
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They are typically 1-2 μm in size and generally spherical or heart-shaped. The genus Triparma is actively studied because of their close relationship to the diatoms, and it has been discovered that they have different silica-limitation responses. While diatoms stop growing and cell division is inhibited under low-silica conditions, Triparma continues to grow and divide normally even under nanomolar concentrations of silica, although the silica plates are no longer produced. Photosynthetic pigments present in bolydophyte chloroplasts include chlorophylls a, c1, c2, c3, fucoxanthin, diatoxanthin, diadinoxanthin.
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All of these features provide fucoxanthin with powerful antioxidant activity. In macroalgal plastids, fucoxanthin acts like an antenna for light harvesting and energy transfer in the photosystem light harvesting complexes. In diatoms like Phaeodactylum tricornutum, fucoxanthin is protein- bound along with chlorophyll to form a light harvesting protein complex. Fucoxanthin is the dominant carotenoid, responsible for up to 60% of the energy transfer to chlorophyll a in diatoms When bound to protein, the absorption spectrum of fucoxanthin expands from 450-540 nm to 390-580 nm, a range that is useful in aquatic environments.
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This sinking is induced by either a loss of buoyancy control, the synthesis of mucilage that sticks diatoms cells together, or the production of heavy resting spores. Sinking out of the upper mixed layer removes diatoms from conditions unfavourable to growth, including grazer populations and higher temperatures (which would otherwise increase cell metabolism). Cells reaching deeper water or the shallow seafloor can then rest until conditions become more favourable again. In the open ocean, many sinking cells are lost to the deep, but refuge populations can persist near the thermocline.
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Most centric and araphid pennate diatoms are nonmotile, and their relatively dense cell walls cause them to readily sink. Planktonic forms in open water usually rely on turbulent mixing of the upper layers of the oceanic waters by the wind to keep them suspended in sunlit surface waters. Many planktonic diatoms have also evolved features that slow their sinking rate, such as spines or the ability to grow in colonial chains. These adaptations increase their surface area to volume ratio and drag, allowing them to stay suspended in the water column longer.
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This theory is backed up by the fact that modern lineages of roseobacters are abundant components of the phycosphere of these two phytoplankton groups. Genes related to mobility and chemotaxis in the ancestor of the Roseobacter clade would have potentially allowed reseobacter to sense and swim towards these phytoplankton. Later on it was found that some lineages of Roseobacter are also associated with diatoms. All dinoflagellates, coccolithophorids and diatoms are red-plastid-lineage phytoplankton, and the coincidence of the red-plastid radiation and Roseobacter genome innovation is consistent with adaptive evolution.
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The biology of silicon had been shunned by all biochemists, the dogma being that it was inert. Volcani realized that diatoms, whose life cycle is based on silicon, provided an ideal experimental canvas. From 1959 onward, his lab made multifaceted discoveries centered on biologically active silicon in marine diatoms. The lab became a focal point for the study of silicon metabolism and biomineralization at the molecular level, embracing experimental techniques, from elegant electron microscopy of diatom shells to gene cloning and the expression of silicon transporting proteins in frog eggs.
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The ratio between the concentrations of nitrogen, phosphorus and silicate in particular areas of the ocean dictates competitive dominance within phytoplankton communities. Each ratio essentially tips the odds in favor of either diatoms or other groups of phytoplankton, such as coccolithophores. A low silicate to nitrogen and phosphorus ratio allows coccolithophores to outcompete other phytoplankton species; however, when silicate to phosphorus to nitrogen ratios are high coccolithophores are outcompeted by diatoms. The increase in agricultural processes lead to eutrophication of waters and thus, coccolithophore blooms in these high nitrogen and phosphorus, low silicate environments.
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Size and distribution of phytoplankton are also related to fronts. Microphytoplankton (>20μm) are found at fronts and at sea ice boundaries, while nanophytoplankton (<20μm) are found between fronts. Studies of phytoplankton stocks in the southern sea have shown that the Antarctic Circumpolar Current is dominated by diatoms, while the Weddell Sea has abundant coccolithophorids and silicoflagellates. Surveys of the SW Indian Ocean have shown phytoplankton group variation based on their location relative to the Polar Front, with diatoms dominating South of the front, and dinoflagellates and flagellates in higher populations North of the front.
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Diatomaceous earth is a soft, siliceous, sedimentary rock made up of microfossils in the form of the frustules (shells) of single cell diatoms. This sample consists of a mixture of centric (radially symmetric) and pennate (bilaterally symmetric) diatoms. This image of diatomaceous earth particles in water is at a scale of 6.236 pixels/μm, the entire image covers a region of approximately 1.13 by 0.69 mm. Microfossils are fossils that are generally between 0.001mm and 1 mm in size, the study of which requires the use of light or electron microscopy.
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Scanning electron micrographs of frustules from some algae species - scale bar = 10 micrometres in a,c and d and 20 micrometres in b A frustule is the hard and porous cell wall or external layer of diatoms. The frustule is composed almost purely of silica, made from silicic acid, and is coated with a layer of organic substance, which was referred to in the early literature on diatoms as pectin, a fiber most commonly found in cell walls of plants. This layer is actually composed of several types of polysaccharides.Progress in Phycological Research: v.
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Attheya armata is a species of diatoms in the genus Attheya.Crawford, R. M., Gardner, C., Medlin, L. K. 1994. The genus Attheya. I. A description of four new taxa, and the transfer of Gonioceros septentrionalis and G. armatus.
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Antibiotics secreting Streptomyces are likely to be found. 250px Green algae - especially Chlorella sp. - are present all over the lake except for the springcave and its surroundings. Navicula cryptocephala and Navicula capitatoradiata are common diatoms in the lake.
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An Illustrated Guide to Some Common Diatom Species from South Africa. Gezina: Water Research Commission. .Mishra, M., Arukha, A.P., Bashir, T., Yadav, D. and Prasad, G.B.K.S. (2017) "All new faces of diatoms: potential source of nanomaterials and beyond".
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Some members of Stramenopila are brown algae, diatoms, and water molds. An example of Stramenopila are Peronosporomycetes. The most well-known example of Peronosporomycetes is Phytophthora infestans. This organism caused the Great Famine of Ireland in the 1850s.
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The animal uses its proboscis to probe in muddy gravel or in sand, searching for food. It feeds on macro algae particles, benthic diatoms Pleurosignia sp., on detritus and also remains of animal matter, such as sponge spicules.
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"All About Diatoms" Los Angeles Herald (September 6, 1891): 6. via Newspapers.com She also published poetry. In her seventies, she consulted on topics including marine biology, entomology, botany, and geology from her cottage and garden in San Pedro.
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Attheya septentrionalis is a species of diatoms in the genus Attheya.Crawford, R. M., Gardner, C., Medlin, L. K. 1994. The genus Attheya. I. A description of four new taxa, and the transfer of Gonioceros septentrionalis and G. armatus.
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In Diatoms, the Heterokontophyta have polyphyletic turgor-resistant cell walls. Throughout these organisms' life cycle, carefully controlled turgor pressure is responsible for cell expansion and for the release of sperm, but not for things such as seta growth.
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Thalassiosira symmetrica is a species of marine centric diatoms. It differs with T. eccentrica in the value processes and distribution patterns. The latter species is more abundant in inshore waters, while T. symmetrica has been found in oceanic waters.
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This caused diatoms to take in less silica for the formation of their frustules. Increased mixing of the oceans renews silica and other nutrients necessary for diatom growth in surface waters, especially in regions of coastal and oceanic upwelling.
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During the same years, he was named Honorary Custodian of Diatoms at the United States National Museum. From 1944 to 1966 he became an Associate Curator, and was Botanist Emeritus of Cryptogams from 1967 till his death in 1979.
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M. membranacea can eat food particles such as bacteria, flagellates, diatoms, and other small, planktonic organisms by extracting them from the water with their lophophore. They can also supplement their diet with dissolved organic nutrients through the absorptive epidermis.
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Phytoplanktons (cyanobacteria), green algae (Spirogyra,Oedogonium), diatoms,etc. are the pioneer colonizers in the initial stage,starting from a water body,such as a pond. Their spores are carried by air to the pond. The phytoplankton are followed by zooplankton.
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E. Monosson and C. Cleveland (eds.). Washington DC. but a cadmium-dependent carbonic anhydrase has been found in some marine diatoms. Cadmium is considered an environmental pollutant that causes health hazard to living organisms.Xu, Liang, Zhang, Fei, Tang, Mingjia, et al.
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They have a close association with benthic diatoms as their main source of food (Bass et al., 2012). There are only two Reticulamoeba species described to date and the protozoologist Karl Grell discovered both of them (Bass et al., 2012).
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Auxospore formation by the silica-sinking, oceanic diatom Fragilariopsis kerguelensis (Bacillariophyceae). J. Phycol. 42, 1002-1006. Auxospores can also play a role in sexual reproduction in diatoms, and may be formed after haploid gametes fuse to form a diploid zygote.
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Siliceous rocks are sedimentary rocks that have silica (SiO2) as the principal constituent. The most common siliceous rock is chert; other types include diatomite. They commonly form from silica-secreting organisms such as radiolarians, diatoms, or some types of sponges.
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Pseudo-nitzschia species synthesize their own food through the use of light and nutrients in photosynthesis. The diatoms have a central vacuole to store nutrients for later use and a light- harvesting system to protect themselves against high-intensity light.
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Alabama Department of Conservation and Natural Resources. 2008. Largescale Stoneroller. It is a herbivorous fish which eats diatoms, green algae, and blue-green bacteria, with a tendency to ingest less sand and silt than the central stoneroller.Fowler, James, Taber, Charles. 1985.
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During the spring months, the DCM coincides with the upper surface of the nitracline, making the water nutrient-rich for diatoms Cyclotella striata and crysophytes Dinobryon bavaricum to thrive in. During the summer months, the DCM deepens, and productivity within the layer almost becomes entirely light dependent. Similar to the chlorophyll structures found in oceans, the DCM becomes incredibly fluid and variable, such that certain phytoplankton species (diatoms Synedra ulna, Cyclotella comta and green flagellates) begin to dominate, despite being absent during the spring productivity period. Overall, the phytoplankton community between the epilimnion and the DCM in Lake Tahoe differ with size.
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Wild guppies feed on algal remains, diatoms, invertebrates, plant fragments, mineral particles, aquatic insect larvae, and other sources. Algal remains constitute the biggest proportion of wild guppy diet in most cases, but diets vary depending on the specific conditions of food availability in the habitat. For example, a study on wild Trinidad guppies showed that guppies collected from an oligotrophic upstream region (upper Aripo River) mainly consumed invertebrates, while guppies from a eutrophic downstream region (lower Tacarigua River) consumed mostly diatoms and mineral particles. Algae are less nutritious than invertebrates, and the guppies that feed mainly on algae have poor diets.
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Diatom bloom in the South Atlantic Ocean, off the coast of Argentina. Atmospheric carbon dioxide levels have been increasing exponentially since the Industrial Revolution and researchers are exploring ways to mitigate atmospheric carbon dioxide levels by increasing the uptake of carbon dioxide in the surface ocean via photosynthesis. An increase in the uptake of carbon dioxide in the surface waters may lead to more carbon sequestration in the deep sea through the biological pump. The bloom dynamics of diatoms, their ballasting by opal silica, and various nutrient requirements have made diatoms a focus for carbon sequestration experiments.
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Although diatoms may have existed since the Triassic, the timing of their ascendancy and "take-over" of the silicon cycle occurred more recently. Prior to the Phanerozoic (before 544 Ma), it is believed that microbial or inorganic processes weakly regulated the ocean's silicon cycle. Subsequently, the cycle appears dominated (and more strongly regulated) by the radiolarians and siliceous sponges, the former as zooplankton, the latter as sedentary filter- feeders primarily on the continental shelves. Within the last 100 My, it is thought that the silicon cycle has come under even tighter control, and that this derives from the ecological ascendancy of the diatoms.
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His studies of silicon metabolism often involved growing diatoms of various species in different concentrations of silicon and then studying the effect on specific metabolic pathways. These experiments studied pigments, lipids, amino acids, cell wall synthesis, DNA synthesis, ribosomes, sodium-potassium membrane pumps, cell membrane characterization, glycolate metabolism, cyclic nucleotide metabolism, protein kinases, and a catalog of genes that were turned on by silicon. Several papers centered on the effects of silicon on photorespiration in diatoms. He published over 100 papers related to silicon metabolism and co- edited Silicon and Siliceous Structures in Biological Systems (Springer, 1981).
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Macronutrients, such as phosphorus, nitrogen, and silicate are strongly impacted by increased residence times in reservoirs created by dam construction throughout the Columbia River Basin. Exact nutrient retention rates can vary between 16 and 98 percent depending on local hydrology, reservoir design, and location in the basin. However, this increase in nutrient retention rates in the Columbia River basin has generally modified the relative ratios of available nutrients from their natural state, which has subsequently altered the efficiency of compound usage by primary producers such as diatoms. Diatoms are directly affected by the hydrodynamic changes that reservoirs create.
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Nitzschia is found mostly in colder waters, and is associated with both Arctic and Antarctic polar sea ice, where it is often found to be the dominant diatom. Nitzschia includes several species of diatoms known to produce the neurotoxin known as domoic acid, a toxin responsible for the human illness called amnesic shellfish poisoning. The species N. frigida is found to grow exponentially even at temperatures between −4 and −6 °C.L. Aletsee and J.Jahnke, 'Growth and productivity of the psychrophilic marine diatoms Thalassiosira antarctica Comber and Nitzschia frigida Grunow in batch cultures at temperatures below the freezing point of sea water.
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The Fur Formation is a unit of diatomitic sediment approximately 60 meters thick consisting of diatoms and clay minerals with up to 180 layers of volcanic ash.Pedersen, G.K. & Surlyk, F. 1983: The Fur Formation, a late Paleocene ash-bearing diatomite from northern Denmark. Bulletin Geological Society of Denmark, 32, 43-65. In Danish literature the formation has informally been referred to as the moler (Ler means clay). The diatomite comprises 2/3 opal tests of diatoms and 1/3 clay, interbedded with layers of volcanic ash and a few limestone horizons (‘cementstones’), and has exceptionally complete fossil preservation.
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The rainbow cichlid is an omnivore. In the wild, it mostly eats flocculent detritus, with a preference for filamentous algae, simple algae, and diatoms. It can also prey on smaller fish and insects. In captivity, it readily consumes commercial flakes or pellets.
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The Cretaceous record of diatoms is limited, but recent studies reveal a progressive diversification of diatom types. The Cretaceous–Paleogene extinction event, which in the oceans dramatically affected organisms with calcareous skeletons, appears to have had relatively little impact on diatom evolution.
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As the diatoms fell to the bottom of the lake, any plants or animals that had recently died were preserved by the diatom falls. Fine layers of clays and muds interspersed with layers of ash form "paper shales" holding beautifully-preserved fossils.
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Shellfish poisoning includes four syndromes that share some common features and are primarily associated with bivalve molluscs (such as mussels, clams, oysters and scallops.) As filter feeders, these shellfish may accumulate toxins produced by microscopic algae, such as cyanobacteria, diatoms and dinoflagellates.
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Lothar Geitler (18 May 1899 – 1 May 1990) was an Austrian botanist and cytologist. He was born in Vienna. His main research interests included blue- green algae (Cyanophyta), diatoms, lichen symbioses and chromosome structure. The genus Geitlerinema was named in his honour.
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Kelly Jemison (left) and Charlie King (right) stand at the base of Mt. Erebus, Antarctic (2006). Kelly Jemison is an American academic geologist specializing in Antarctic diatoms. She studied at Florida State University. She has participated in the ANDRILL (ANtarctic geological DRILLing) project.
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Ruth Myrtle Patrick (November 26, 1907 – September 23, 2013) was an American botanist and limnologist specializing in diatoms and freshwater ecology. She authored more than 200 scientific papers, developed ways to measure the health of freshwater ecosystems and established numerous research facilities.
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Sand shiners are omnivorous fish, feeding on aquatic and terrestrial insects, bottom ooze and diatoms and are often observed in large schools which frequently feeding in shallow waters.Koster, W. J. 1957. Guide to the Fishes of New Mexico. Univ. New Mexico Press, Albuquerque.
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The name Cyclotella is derived from the Greek term kyklos, meaning “circle.” While “circle” can be used to describe many diatoms, Cyclotella spp. are all circular and have a girdle band arrangement that makes the structure of the organism resemble a wheel.Brébisson, [L.
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Digestion time for cnidarians is highly dependent on the temperature and conditions of the environment each organism is in. The same study in the Kongsfjorden, found that O. dichotoma had a digestion time for diatoms of about 20 hours at 6°C.
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The diet is mostly zooplankton, but in the North Pacific Gyre, Warming's lantern fish was found to feed at night on floating mats of Rhizosolenio (diatoms). This example of herbivory, unusual among deep sea fish, has led to modifications of the gut.
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Increased nutrient and light availability result in rapid phytoplankton growth towards the end of winter. The dominant species, such as diatoms, are small and have quick growth capabilities. 2\. These plankton are consumed by zooplankton, which become the dominant plankton taxa. Spring 3\.
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Naviculaceae is a diatom family in the order Naviculales. Naviculaceae are typically composed of lineate areolae, one of the many forms of areolae. Some of the other areolae are punctate (Gomphoneis) and loculate (Diploneis). These can be found among other families of diatoms including Thalassiosiraceae.
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Eugene F. Stoermer (March 7, 1934February 17, 2012) was a leading researcher in diatoms, with a special emphasis on freshwater species of the North American Great Lakes. He was a professor of biology at the University of Michigan School of Natural Resources and Environment.
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Thalassiosira weissflogii is a species of centric diatoms, a unicellular microalga. It is found in marine environments and also in inland waters in many parts of the world. It is actively studied because it may use C4-plant style strategies to increase its photosynthetic efficiency.
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Chaetocerotaceae is a diatom family (Bacillariophyta). This family comprise the three genera Attheya T. West, Bacteriastrum Shadbolt and Chaetoceros Ehrenberg. Chaetoceros is perhaps the largest and most species rich genus of marine planktonic diatoms. The taxonomic status within Chaetocerotaceae at present is somewhat unclear.
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Major speciation events of radiolarians occurred during the Mesozoic. Many of those species are now extinct in the modern ocean. Scientists hypothesize that competition with diatoms for dissolved silica during the Cenozoic is the likely cause for the mass extinction of most radiolarian species.
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Keyhole limpets are in essence herbivorous, feeding primarily on algae, but are also detritus feeders. A few species in the genera Diodora and Emarginella are carnivorous, feeding on sponges. Puncturella has been reported to digest diatoms and detritus. Puncturella aethiopica feeds mainly on Foraminifera.
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Phragmites reed communities are dominant in wetland areas. In the coastal area, various saltmarsh plants are developing such as halophyte communities. Many biological organisms are in the inter-tidal zone. The surface of the tidal flat is an important habitat for diatoms and plankton.
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The beautiful crinoid is a suspension feeder. They filter feed on marine microorganisms like algae, diatoms, and larvae. They also consume marine snow (detritus). This filtration occurs on their cirri, which is linked to the gut near the mouth and anus on the centrodorsal plate.
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One proposal, by Linda Medlin and co-workers commencing in 2004, is for some of the centric diatom orders considered more closely related to the pennates to be split off as a new class, Mediophyceae, itself more closely aligned with the pennate diatoms than the remaining centrics. This hypothesis—later designated the Coscinodiscophyceae-Mediophyceae- Bacillariophyceae, or Coscinodiscophyceae+(Mediophyceae+Bacillariophyceae) (CMB) hypothesis—has been accepted by D.G. Mann among others, who uses it as the basis for the classification of diatoms as presented in Adl. et al.'s series of syntheses (2005, 2012, 2019), and also in the Bacillariophyta chapter of the 2017 Handbook of the Protists edited by Archibald et al.
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Reproduce sexually (sexual reproduction is oogamous) and asexually [Guiry 2011]. Skeletonema belong to the morphological category referred to as centric diatoms. These are classified by having valves with radial symmetry and the cells lack significant motility [Horner 2002]. Skeletonema are cylindrical shaped with a silica frustule.
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The main one is the type of diatoms found in the sediment. Some species require salt water, while others require fresh. Other invertebrates serve as marker species as well. Also, periods of maximum supply from melt water are marked by low organic carbon in the sediment.
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L. albus is mostly found on rocky coasts associated with the kelp Macrocystis pyrifera. It is more numerous in exposed locations. It is a herbivore and seems to feed on whatever species of alga grow nearby. Juveniles feed on crustose coralline algae, diatoms and algal detritus.
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The hindwings have two transverse brownish bands, separated by a white area. There is a triangular patch of fine black speckling. Adults are on wing from May to September in two generations per year. The larvae are aquatic and feed on diatoms, including Navicula and Cymbella species.
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S H Meakin's hobby was studying and mounting diatoms, for which activity - paradoxically - he is far better known today. (See Google, S H Meakin : the preceding Normanby Park details are taken from an interview in 2020 with Harry Meakin's grandson, Christopher Meakin, citing known family history).
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Since 24-norcholestane origins are still unknown, the synthesis of it is also unknown as well. However, some pathways have been proposed. Possible sources of 24-norcholestane include 24-norcholesterol, which is present in many marine invertebrates and some algae in addition to diatoms and dinoflagellates.
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Shiners are planktivores, feeding on a variety of zooplankton, protozoans and diatoms. They move with a planktonic food source up toward the surface at dusk, and move back down at dawn.Simon, T. P. 1999. Assessing the sustainability and biological integrity of water resources using fish communities.
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Of the species, James's flamingo has the finest filter-feeding apparatus.Conway, William G. "CARE OF JAMES'S FLAMINGO Phoenicoparrus jamesi Sclater AND THE ANDEAN FLAMINGO Phoenicoparrus andinus R. A. Philippi IN CAPTIVITY". International Zoo Yearbook. 5(1), 162-164 The flamingo feeds on diatoms and other microscopic algae.
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The size of Cyclotella varies by species. C. atomus has a diameter of 5-7 μm, whereas C. quillensis can have a diameter up to 24-54 μm.Bailey, L.W. (1922). Diatoms from the Quill Lakes, Saskatchewan, and from Airdrie, Alberta.Contributions to Canadian Biology 11(1): 157-165.
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Marine and terrestrial contributions to the silica cycle are shown, with the relative movement (flux) provided in units of Tmol Si/yr. Marine biological production primarily comes from diatoms. Estuary biological production is due to sponges. Values of flux as published by Tréguer & De La Rocha.
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Arcella inhabit freshwater pools, eutrophic waters, marshes, mosses, as well as wet foliage. Few species can also be found in soils. They nourish on diatoms, unicellular green algae or animal protozoa such as flagellates and ciliates. Most species are worldwide-distributed, but some have restricted distributions, e.g.
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Ninety percent of marine life lives in the photic zone, which is approximately two hundred meters deep. This includes phytoplankton (plants), including dinoflagellates, diatoms, cyanobacteria, coccolithophorids, and cryptomonads. It also includes zooplankton, the consumers in the photic zone. There are carnivorous meat eaters and herbivorous plant eaters.
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The green chromide lives in brackish water habitat types, such as river deltas. It eats mainly aquatic plants, including filamentous algae and diatoms, but it consumes the occasional mollusk and other animal matter. This species engages in attentive parental care in which several adults care for each brood.
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The genus Attheya consist of small single celled diatoms. Some of these species were earlier regarded to belong to Chaetoceros, or to Gonioceros, the taxonomic status of some of these species are still debated.Crawford, R.M., Hinz, F. and Koschinski, P. 2000. The combination of Chaetoceros gaussii (Bacillariophyta) with Attheya.
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Phytoplankton are key primary producers in estuaries. They move with the water bodies and can be flushed in and out with the tides. Their productivity is largely dependent upon the turbidity of the water. The main phytoplankton present is diatoms and dinoflagellates which are abundant in the sediment.
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During the Precambrian, oceanic silica concentrations were an order of magnitude higher than in modern oceans. The evolution of biosilicification is thought to have emerged during this time period. Siliceous oozes formed once silica- sequestering organisms such as radiolarians and diatoms began to flourish in the surface waters.
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Acanthurus dussumieri feeds on algae and detritus. Its diet includes the algal film that grows on rocks and other surfaces as well as diatoms and planktonic particles. The reproduction of this fish has been little studied. Adults are either solitary or occur in small groups but juveniles form shoals.
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Once silicate is depleted in the environment, diatoms are succeeded by smaller dinoflagellates. This scenario has been observed in Rhode Island,Smayda, T.J.(1957). "Phytoplankton studies in lower Narragansett Bay". Limnology and Oceanography 2(4) 342-359Nixon, S.W., Fulweiler, R.W., Buckley, B.A., Granger, S.L., Nowicki, B.L., Henry, K.M. (2009).
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It was initially assigned to Balaenoptera cf. acutorostrata by Shinohara (2012) and thought to be Pliocene in age, but analysis of diatoms in the matrix and preparation showed it to not only late Miocene but also a distinct species of extinct rorqual.Yamashita, S. 1989. Fossils from Numata Town.
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Petrotilapia nigra is a species of cichlid endemic to Lake Malawi where it prefers areas with rocky substrates. It grazes on diatoms that it finds on the algae growing on the rocks. This species can reach a length SL. This species can also be found in the aquarium trade.
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The San Bernardino springsnail is aquatic, breathing through gills. It feeds on diatoms and possibly bacterial films and detritus. It probably prefers sand or cobble substrates to silt and organic deposits. Like many similar molluscs, the species is preyed upon by a variety of birds, amphibians and fishes.
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D. gilvipes in both larvae and nymph stages are categorized as scraper-grazers. They are grazers on periphyton attached to the submerged rocks in the rivers. They typically eat Diatoms (Synedra ulna and Achnanthes lanceolate) and filamentous algal (Stigeoclonium tenueetae, Ulothrix spp., and Klebsormidium fluitans) with the occasion detritus.
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An example of impacts from nitrogen is a shift in the types of plankton that make up their community in Long Island Sound. Over the last several decades, excess nitrogen may have adversely affected diatoms—microscopic, single-celled algae at the base of the food chain, which make shells ('frustules') of opaline silica. When diatoms are less productive, they are replaced by other phytoplankton such as dinoflagellates or blue-green algae, which grow well in waters with high nitrogen levels, but do not need silica.; Such changes in the base of the food chain leads to consequences such as an increase in abundance of jellyfish and decline in shellfish and other fish.
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Around this time, in the later 1920s and through the 1960s, Cleve's research refocused again on both living and fossil diatoms in the Baltic Sea. Her research also extended into related paleobotanical issues, including the changes in water level of the Baltic Sea, then an inland sea, in the late Ice Age and the period shortly after. Cleve performed boundary analyses derived from diatom studies to determine the changes in the Baltic's connection with the ocean; these are considered to have dubious validity because of the possibility of redeposited diatoms in the sediment. In her discourse with the contemporary Scandinavian scientific establishment, Cleve found conflict as a proponent of the oscillation theory.
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Diatoms (diá-tom-os 'cut in half', from diá, 'through' or 'apart'; and the root of tém-n-ō, 'I cut'.) "cut in half" (= dichó-tom-os) – "through" or "apart" and the root of "I cut". are a major group of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of the Earth's biomass: they generate about 20 to 50 percent of the oxygen produced on the planet each year,The Air You're Breathing? A Diatom Made That take in over 6.7 billion metric tons of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans.
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116 The mummy has been identified as probably a male of an established age of 30 +/- 5 years old. The length of the individual has been estimated at . The teeth of SO10-IX did not have cavities and in the mouth remains of algae and diatoms have been discovered.Martínez et al.
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These are generally multi-species associations of Rhizosolenia species of diatoms. This larger phytoplankton may reach up to 10s of centimeters in size. These mats are particularly abundant in the NPSG. Their abundance in this ecosystem suggests a higher flux of nutrients in the NPSG than was predicted in classic theories.
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Mist covering the boating in Kodaikanal Lake. The Lake has moderate to dense growth of macrophytes of all types. The littoral zone of the lake is reported to be rich in periphytic biota associated with macrophytes. Diatoms, protozoans and rotifers which are also associated with macrophytes are found in the lake.
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They breed once a day to form baby diatomettes and this creates a very localized food source, that all the fish are attracted to. The white color of the line is caused by the huge collection of diatoms, the cooler water and the whitecaps, formed by the turbulence in the water.
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Also, scientists have measured the concentrations of these diatoms by lasers in low flying aircraft, during normal conditions and during the time in which the white line is present, and it has been found that the concentrations of these algae is up to 100 times greater in the white line period.
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Peter Fidler (1769–1822) naturalist, surveyed and mapped Saskatchewan and wrote reports on wildlife observation. Loring Woart Bailey (1839–1925), naturalist studied algae and identified diatoms in Saskatchewan. Archibald Stansfeld Belaney, Grey Owl (1888–1938) conservationist lived in the Prince Albert National Park and appeared in films advocating wildlife preservation.
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While some can be maintained in dual culture with the host, most have not been cultured, but they have been detected, using molecular techniques, in soil samples, and in freshwater and marine ecosystems. Zoospores have been observed, along with cysts, and the cells of some species are attached to diatoms.
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When temperature, light and nutrient availability are adequate to phytoplankton growth, surface waters may host algae or cyanobacteria blooms.Maria da Conceição Raimundo Santos et al., 2004, p.396 In eutrophic waters, cyanobacteria often dominate the summer and early autumn phytoplankton, while during winter and spring they are replaced by diatoms.
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Widgeonweed grows at the lakeshores. Charophytes, Chara and Myriophyllum are two further aquatic plants that have been identified in the lake. During its highstands, algal bioherms and stromatolithes developed in the water. Diatoms and ostracodes have been identified in the lake sediments, and amphipods have been found in the lake waters.
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Phaeodactylum tricornutum is one of three diatoms whose genome has been sequenced (the others being Thalassiosira pseudonana and Fragilariopsis cylindrus). The genome contains approximately 10% prokaryote-like genes, an unusually large proportion. Over 30000 expressed sequence tags (ESTs) have been organized into the Diatom EST Database.Maheswari, U. et al. 2005.
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Because of this bloom-and-bust cycle, diatoms are believed to play a disproportionately important role in the export of carbon from oceanic surface waters (see also the biological pump). Significantly, they also play a key role in the regulation of the biogeochemical cycle of silicon in the modern ocean.
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Forensic limnology is a sub-field of forensic botany, which examines the presence of diatoms in crime scene samples and victims. Different methods are used to collect this data but all identify the ratios of different diatom colonies present in samples and match those samples with locations at the crime scene.
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The fish is endemic to the Tugela River system in South Africa. It prefers deep pools and slow- flowing parts of the rivers in which it lives. The fish feed on green algae, detritus and diatoms. They fish migrate upstream in shoals during spring and summer to be able to breed.
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It is also an introduced species in Eurasia, including Austria, the Czech Republic, France, Germany, and Israel. This common snail occurs in many types of freshwater habitat, such as ponds and lakes. It consumes diatoms and other periphyton that it scrapes off of surfaces. It sometimes rests attached to water plants.
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The main source of photosynthetically derived energy is phytoplankton. Generally speaking, diatoms and microflagellates produce most of the bioavailable carbon in the estuary.Jassby and Cloern 2000 Other types, notably the dinoflagellates, may produce harmful algal blooms, or red tides, that are less readily available for assimilation into the foodweb.Anderson et al.
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Larvae and juveniles have a superior mouth, but at 3–4 months they change to adult feeding mode (undermouth) and start grazing the bottom, eating benthic diatoms and detritus from hard substrate. Breeding females deposit sticky eggs on gravel bottom in shallow parts of rivers with moderate to strong current.
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An analysis of gene sequences was performed in 1996, which placed it into the group Stramenopiles. Other Stramenopiles include brown algae, mildew, diatoms, the organism that caused the Great Famine of Ireland, and the organism responsible for Sudden oak death disease. However, the position of Blastocystis within the stramenopiles remains enigmatic.
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Like other chitons, it is a slow moving grazer that consumes several species of brown and red algae including kelps, sea lettuce, and encrusting diatoms. They're also known to eat sponges, tiny barnacles, spirobid polychaetes, and bryozoans. Their predators include sea urchins, leather stars, black oystercatchers, glaucous- winged gulls, and humans.
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Biomineralization is the process by which living organisms produce minerals, often to harden or stiffen existing tissues. Such tissues are called mineralized tissues. Examples include silicates in algae and diatoms, carbonates in invertebrates, and calcium phosphates and carbonates in vertebrates. Other examples include copper, iron and gold deposits involving bacteria.
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Fish are unharmed by it, but mammals are. California sea lions are disproportionately affected because they feed closer to shore, where more of these diatoms are present. When consumed by marine mammals, DA activates neural pathways in the brain, specifically, the hippocampus. This neural activation is unregulated and results in seizures.
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Release of dissolved organic matter by coastal diatoms. Limnol. Oceanogr. 52, 798–807. doi: 10.4319/lo.2007.52.2.0798 Nonetheless, this release of extracellular DOC is enhanced under high light and low nutrient levels, and thus should increase relatively from eutrophic to oligotrophic areas, probably as a mechanism for dissipating cellular energy.
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Abas is an extinct genus of diatoms consisting of only one known species: Abas wittii. Originally observed as a fossil genus classified with diatom spore forms under the name Syringidium.M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2014. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway accessed 21 December 2014.
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The Indian mackerel do not guard their eggs, which are left to develop on their own. Juveniles feed on phytoplankton like diatoms and small zooplankton including cladocerans and ostracods. As they mature, their intestines shorten, and their diet changes to primarily include macroplankton such as the larvae of shrimp and fish.
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Exceptions are the methyl pentoses L-fucose and L-rhamnose and the pentose L-arabinose. Rhamnose can be isolated from Buckthorn (Rhamnus), poison sumac, and plants in the genus Uncaria. Rhamnose is also produced by microalgae belonging to class Bacillariophyceae (diatoms). Rhamnose is commonly bound to other sugars in nature.
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Chromista and Alveolata algae (e.g., chrysophytes, diatoms, phaeophytes, dinophytes) seem to have evolved from bikonts that have acquired red algae as endosymbionts. According to this theory, over time these endosymbiont red algae have evolved to become chloroplasts. This part of endosymbiotic theory is supported by various structural and genetic similarities.
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The E. zodiacus cell has an average size between 10-61 µm along the apical axis. The cell wall is silicified, as is characteristic of all diatoms. The thickness of this cell wall changes with season. Cells are flattened and interlock by two apical elevations (horns) to form long curved colony formations.
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One example is the diatometer, a device that is deployed in the water that becomes colonized by diatoms, and then is removed for analysis.“Tools of a Scientist”. Urban Rivers Awareness. 2004. In situ sampling devices are set up at increasing distances from the pollution source in the case of point source pollution.
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The process occurs in specialized cells known as sclerocytes. Biosilica formation in Suberites differs from other species that utilize biosilica in this regard. Most other species, such as certain plants and diatoms, simply deposit a supersatured biosilica solution. The network of silica found in sponges mediates much of the sponges’ neural communications.
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In the environment, fungal biofilms are an area of ongoing research. One key area of research is fungal biofilms on plants. For example, in the soil, plant associated fungi including mycorrhiza have been shown to decompose organic matter, protect plants from bacterial pathogens. Biofilms in aquatic environments are often founded by diatoms.
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It lives in the northeastern Atlantic Ocean from Iceland to Senegal and Cape Verde, including the Mediterranean Sea and the southwestern Black Sea. This species is partially migratory, heading northwards in summer. It feeds mainly on benthic diatoms, epiphytic algae, small invertebrates and detritus. The thicklip grey mullet lays its eggs in winter.
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MBio, 10(2): e01189-18. . 50px Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License.Gutierrez MH, Jara AM, Pantoja S (2016) "Fungal parasites infect marine diatoms in the upwelling ecosystem of the Humboldt current system off central Chile". Environ Microbiol, 18(5): 1646–1653. .
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Silicate is a required nutrient for diatoms, which form siliceous shells, within the surface waters of this coastal region. The observed shift in silicate transport out of the Columbia River estuary since 1970 has resulted in the development of seasonal silicate limited regions of diatom production in coastal waters near the estuary.
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Leptogorgia sarmentosa with polyps extended, colonised by Alcyonium coralloides Leptogorgia sarmentosa is a suspension feeder. The polyps extend their tentacles to filter particles from the water flowing past the colony. The diet includes zooplankton such as dinoflagellates, diatoms and ciliates as well as particles of organic detritus. Colonies are either male or female.
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Noted for her preparation of diatoms and pollens, Booth earned a Diploma of Honor in Entomology (Women's Department) at the 1884–85 New Orleans World's Industrial and Cotton Centennial Exposition. In 1916, Booth donated a series of her photomicrographs to the Springfield Museum of Natural History. Booth died on September 15, 1922.
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The shoreline is densely populated up to depths of with starry stonewort, or Nitellopsis obtusa. In the shallower areas, major species include Myriophyllum spicatum, Elodea nuttallii, Potamogeton lucens, and Potamogeton perfoliatus, as well as numerous other species of pondweed. There is very little phytoplankton in Auesee. Only diatoms and cryptophyceae occur regularly.
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Friedrich Traugott Kützing (8 December 1807 in Ritteburg – 9 September 1893) was a German pharmacist, botanist and phycologist. Despite his limited background in regard to higher education, Kützing made significant scientific contributions. In 1833, he demonstrated differences between diatoms and desmids, thus separating the two groups into families of their own.Diatom.org Marginalia no.
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Mixotrophic dinoflagellates can feed on various organisms including bacteria, picoeukaryotes, nanoflagellates, diatoms, protists, metazoans and other dinoflagellates, as well. Feeding and digestion rates in mixotrophic dinoflagellates are lower than those in strictly heterotrophic dinoflagellates. Mixotrophic dinoflagellates do not feed on blood, eggs, adult metazoans, and flesh, such as occurs in some heterotrophic dinoflagellates.
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The first transcriptome of a loricate choanoflagellate led to the discovery of choanoflagellate silicon transporters. Subsequently, similar genes were identified in a second loricate species, Diaphanoeca grandis. Analysis of these genes found that the choanoflagellate SITs show homology to the SIT-type silicon transporters of diatoms and have evolved through horizontal gene transfer.
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Diatoms are unique in the sense that they have valves, created by the two halves of a diatom's test. Cyclotella spp. are no exception, as they form the upper and lower portions of the wall. The girdle bands that support the valves are thin strips of silica and ultimately circumscribe the cell.
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Some authors (e.g., Cavalier-Smith) divide it into two subphyla, Phaeista Cavalier- Smith 1995 (comprising Hypogyristea and Chrysista in some classifications, or Limnista and Marista in others) and Khakista Cavalier-Smith, 2000 (comprising Bolidomonas and diatoms). Others prefer not to use the subphyla, listing only lower taxa (e.g., Reviers, 2002, Guiry & Guiry, 2014).
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Fossilized bacterial mats found in the Monterey Formation further influence this argument. It has been proposed that the generation mechanism may be a biodegradation through bacterial demethylation of hopanes, however the specific organism(s) and mechanism(s) are still unknown. Diatoms are sometimes mentioned also as the primary source for bisnorhopane generation.
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The gravel chub has a pointier snout that allows it to probe the bottom of their habitat in search of small plant particles, desmids, diatoms, and tiny aquatic insects. Gravel chubs have a high density of taste buds on their snouts increasing their sensitivity to taste, which they use to locate their prey.
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Transport and delivery of other trace metals in the Gulf of Alaska are also enhanced by Haida eddies and may result in increased burial of trace metals in marine sediments where they can no longer be used to support biological growth. Evidence suggests Haida eddies may be an important source of dissolved silver ions, with eddy surface water concentrations three to four times higher compared to ambient waters. Silicate uptake rates by marine diatoms in Haida eddies are three times that observed in ambient waters, suggesting strong diatom population growth. Haida eddies are important sources of silver for diatom production, as silver is incorporated into the silicate shells of diatoms and the transport of silver associated with Haida eddies promotes diatom growth.
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Diatoms should normally never be present in human tissue unless water was aspirated, and their presence in tissues such as bone marrow suggests drowning, however, they are present in soil and the atmosphere and samples may easily be contaminated. An absence of diatoms does not rule out drowning, as they are not always present in water. A match of diatom shells to those found in the water may provide supporting evidence of the place of death. Drowning in saltwater can leave significantly different concentrations of sodium and chloride ions in the left and right chambers of the heart, but this will dissipate if the person survived for some time after the aspiration, or if CPR was attempted, and have been described in other causes of death.
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Largescale suckers spawn in the spring in shallow water over sandy areas of streams or the sandy or small gravel shoals of lakes. Females may produce up to 20,000 adhesive eggs. The young feed upon small zooplankton until they become bottom dwellers. Then they feed on benthic aquatic invertebrates, diatoms, and other plant material.
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The thin, bottommost layer lies below the chemocline and contains fewer organisms than the slightly thicker black layer. The gray color is due to the presence of pyrite. Here, the empty shells of diatoms can be found. Microbial species here are dominated by methylotrophic methanogens which generate the methane observed in the salt marsh.
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The forewings are whitish with a brownish-orange band across the median area, and three bands near the apex. The hindwings are white with an orange band bordered by a greyish band in the median area. Adults are on wing from late May to September. The larvae are aquatic, feeding on diatoms and algae.
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White studied for a BA in Geology at San Francisco State University. She worked as an intern at the United States Geological Survey in college. In 1989, she was awarded her PhD in Earth Sciences from the University of California, Santa Cruz. White's doctoral research focused on fossil diatoms in the Miocene Monterey Formation.
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Barcoding marker usually combine hypervariable regions of the genome (to allow the distinction between species) with very conserved region (to insure a specificity to the target organism). Several DNA markers, belonging to the nuclear, mitochondrial, and chloroplast genomes (rbcL, COI, ITS+5.8S, SSU, 18S...), have been designed and successfully used for diatoms identification with NGS.
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The existence of Typha suggests that shallow lake phases occurred. Microbialites and stromatolites also formed on the lake shores and together with limnites are used to delimit the lake surface. Ostracods found in the lake include Candonopsis, Cyprideis, Cypridopsis, Cyprilla, Darwinula, Herpetocypris and Limnocytherae. In some places, diatoms were widespread enough to form diatomite deposits.
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In order to regain their original size, it is usually assumed diatoms have to reproduce sexually, although this has not yet been observed in A. formosa. However, there may also be other ways to rejuvenate.Genetic variation in Asterionella formosa: is it linked to frequent epidemic of host-specific parasitic fungus?, De Bruin et al.
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Phaeodactylum tricornutum is a diatom. It is the only species in the genus Phaeodactylum. Unlike other diatoms P. tricornutum can exist in different morphotypes (fusiform, triradiate, and oval), and changes in cell shape can be stimulated by environmental conditions. This feature can be used to explore the molecular basis of cell shape control and morphogenesis.
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Before the centric diatom begins to expand, its nucleus is at the center of one of the valves and begins to move towards the center of the cytoplasmic layer before division is complete. Centric diatoms have a variety of shapes and sizes, depending on from which axis the shell extends, and if spines are present.
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Thalassiosirales is an order of centric diatoms. The order currently contains 471 species. Species in the order Thalassiosirales are common in brackish, nearshore,and open-ocean habitats, with approximately the same number of freshwater and marine species. The Thalassiosirales species Thalassiosira pseudonana was chosen as the first eukaryotic marine phytoplankton for whole genome sequencing.
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Diplotaxodon macrops is a species of haplochromine cichlid which is endemic to Lake Malawi. It is found throughout the lake in Malawi, Mozambique, and Tanzania. Within Lake Malawi it is abundant near the lake bed over rock shelves. It appears to be a plankton eating species that feeds on insect larvae, crustaceans, and diatoms.
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Gutwiński, R. 1897: Wykaz glonów zebranych z okolic Wadowic-Makowa. Spraw. Komis. Fizjogr. AU 32:97-217. Hilse was a Polish phycologist who studied freshwater systems in hopes of learning more about microorganisms and how they interacted with their environment. Along with Oedogonium, Hilse is also credited with the discovery and classification of many diatoms.
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During the mid Eocene microfossils include diatoms. Above this in the stratigraphic record is glauconite containing siltstone deposited at the end of the Eocene. This material was due to condensed sedimentation due to the added water from the current. During this period around 36 million years ago the plateau started sinking to a depth of .
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Eupolymnia crassicornis are deposit feeders that primarily feed at evening or night. They extend their ciliated tentacles out and along the sea-floor to gather dead organic matter (detritus) that originated as diatoms and other planktonic microorganisms. The collected detritus is then passed along a groove in their tentacles to their mouth, to be consumed.
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Americamysis almyra is an omnivore and examination of its stomach contents showed that its diet includes 31% vascular plant debris and 11% copepods and diatoms. Opossum shrimps play an important part in the estuarine food chain and are consumed in large quantities by such fish as the striped bass, inland silverside, whiffs and flounders.
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Among diatoms, reproduction is primarily asexual by binary fission, with each daughter cell receiving one of the parent’s cell’s two frustules. However, this asexual division results in a size reduction. To restore the cell size of a diatom population, sexual reproduction must occur. Vegetative diploid cells undergo meiosis to produce active and passive gametes.
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Fish in the Missouri National Recreational River area inc. sand shiners The sand shiner (Notropis stramineus) is a widespread North American species of freshwater fish in the family Cyprinidae. Sand shiners live in open clear water streams with sandy bottoms where they feed in schools on aquatic and terrestrial insects, bottom ooze and diatoms.
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In a study performed in 1974, it was determined that the optimal osmolar concentration for growth in C. meneghiniana in a medium of 0.5 Osm/L.Schobert, B. (1974). The influence of water stress on the metabolism of diatoms I. Osmotic resistance and proline accumulation in Cyclotella meneghiniana. Zeitschrift für Pflanzenphysiologie. 74(2). 106-120.
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These minerals often form structural features such as sea shells and the bone in mammals and birds. Organisms have been producing mineralised skeletons for the past 550 million years. Ca carbonates and Ca phosphates are usually crystalline, but silica organisms (sponges, diatoms...) are always non crystalline minerals. Other examples include copper, iron and gold deposits involving bacteria.
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For example, they have been found in various aquatic environments such as brackish or freshwater. Skeletonema are found worldwide excluding Antarctic waters [Hevia-Orube 2016]. Some harmful effects these diatoms may have on an ecosystem are attributed to large blooming events which may cause hypoxic events in coastal systems. Additionally, they are known to cause water discoloration [Kraberg 2010].
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Siliceous soils are formed from rocks that have silica (SiO2) as a principal constituent. The parent material of siliceous soils may include quartz sands, chert, quartzite, quartz reefs, granite, rhyolite, ademellite, dellenite, quartz sandstone, quartz siltstone, siliceous tuff, among others. These parent materials sometimes originate from silica-secreting organisms such as radiolarians, diatoms, or some types of sponges.
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The caldera lake may have suffered a catastrophic outburst flood in the past. Diatoms form most of the phytoplankton, with Cyclotella, Melosira, Stephanodiskus and Synedra. Dominant copepod species in summer 2011 include Cyclops scutifer and the dominant cladocerans Daphnia longiremis. Other species as well as rotifers are also present, they constitute sources of food for sockeye salmons.
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These structures are composed of chitin and are approximately six times stronger and twice the stiffness of vertebrate tendons. Similar to tendons, apodemes can stretch to store elastic energy for jumping, notably in locusts. Calcium carbonates constitute the shells of molluscs, brachiopods, and some tube-building polychaete worms. Silica forms the exoskeleton in the microscopic diatoms and radiolaria.
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I. A description of four new taxa, and the transfer of Gonioceros septentrionalis and G. armatus. Diatom research. 9:27-51. Resting spores are seldom observed. Vegetative cells tend to attach to different substrates, including other diatoms,Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997).
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The jaw parts are very small, ranging from 4 μm to 14 μm. The animal can extend part of its jaw structure outside its mouth while eating. It also extends much of its jaw structure outside its mouth when it is regurgitating items that are indigestible. Its main diet is bacteria, blue-green algae and diatoms.
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Ernst Vilhelm Østrup (21 September 1845 in Roskilde – 16 April 1917 in Frederiksberg) was a Danish botanist and phycologist, mainly working on diatoms. In 1873 he received his cand. polyt. degree, and later worked as a schoolteacher in Copenhagen. His diatom research largely dealt with species found in Denmark, Greenland, Iceland, Faeroe Islands and Jan Mayen.
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A number of fossils were discovered in the sediments, including chara, diatoms, ostracods, snails and vertebrates. Among mammals are Camelops, Equus, mammoth and muskrat. Footprints have been observed at the edges of the lake basin. Arcellacea and foraminifera have been found in lake sediments, including Bolivina goudkoffi, Centropyxis constricta, Lobatula lobatula and a few other, less widespread species.
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The sand crabs with soft shells that have just moulted are kept for bait, while the hard-shelled crabs are thrown back into the sea. The sand crab has been evaluated as an indicator species for monitoring the level of domoic acid-synthesizing diatoms (Pseudo-nitzschia spp.) which sometimes cause toxic blooms off the coast of California.
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Nacella polaris moves around on rocks and soft substrates feeding on algae and diatoms. Its growth rate is slow and it is said to grow to in 21 years and live as long as 60 years. It is gonochoristic, individuals being either male or female, and fertilisation is external. The larval development has been little studied.
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The D. brightwellii cell has a high length to diameter ratio. The cell wall is silicified, as is characteristic of all diatoms. This hard, porous covering is known as the frustule and causes the cell to be more dense than the surrounding water. Oceanic currents and surface winds prevent D. brightwellii cells from sinking beneath the euphotic zone.
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Cleve discovered six forms of dichloronaphthalene and discovered aminonaphthalenesulfonic acids, which are sometimes named after him. He prepared a number of nitrosulfonic acids as well. In 1883, Cleve was the first person to describe the plankton species Nitzschia seriata. In 1890, Cleve began to mainly focus on the field of biology, mainly studying freshwater algae, diatoms, and plankton.
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These blooms also deplete the dissolved oxygen in the water, which is known to cause fish kills. Fish kills result from depleting oxygen levels caused by Ceratium blooms. These dinoflagellates play important roles at the base of the food web. They are sources of nutrients for larger organisms and also prey on smaller organisms such as diatoms.
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Numerous studies are using benthic diatoms for biomonitoring. Because no ideal diatom DNA barcode was found, it has been proposed that different markers are used for different purposes. Indeed, the highly variable cox1, ITS and 28S genes were considered more suitable for taxonomic studies, while more conserved 18S and rbcL genes seem more appropriate for biomonitoring.
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Kermmarec et al. also successfully used the rbcL gene for ecological assessment of diatoms. The rbcL marker is also easily aligned and compared. Moniz and Kaczmarska investigated the amplification success of the SSU, COI, and ITS2 markers and found that the 300 – 400 bp ITS-2 + 5.8S fragment provided the highest success rate of amplification and good species resolution.
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Bacteria either enhance the production of TEP by phytoplankton or contribute to the production of it. TEP presence is necessary for the sedimentation of diatoms, but are not involved in the sedimentation of foraminifera. Prochlorococcus sp. decay from increased solar radiation was found to promote TEP production, suggesting that picocyanobacteria are a source material for TEP.
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Carruthers published scientific work on oaks, diatoms, mosses, fossil ferns, fossil Cycads, Calamites, and Lepidodendron. He was an expert on graptolites and in 1867 he contributed an article on them to the fourth edition of Roderick Murchison's Siluria. He was elected Fellow of the Royal Society in 1871. He was President of the Geologist's Association from 1875–1877.
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The most widespread species is Halocladius variabilis, known from Canada, northern Europe, and the Mediterranean and Black Seas. The larvae can grow to in length. In Nova Scotia, life cycle is univoltine, possibly bivoltine. It is a commensal, potentially symbiotic with marine algae: the larvae feed on diatoms fouling its host, possibly delivering nutrients via faecal material.
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The juveniles and non-territorial adult males similarly occur in singles, pairs or in small shoals of 3-8 fish. It occurs at depths of > This species feeds from the sediment rich aufwuchs on the rocks, raking diatoms and loose algal strands with its mouth. They have also been recorded as eating benthic crustaceans, insects and plankton.
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Other researchers have suggested that the biogenic silica in diatom cell walls acts as an effective pH buffering agent, facilitating the conversion of bicarbonate to dissolved CO2 (which is more readily assimilated). More generally, notwithstanding these possible advantages conferred by their use of silicon, diatoms typically have higher growth rates than other algae of the same corresponding size.
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Heterokont chloroplasts appear to derive from those of red algae, rather than directly from prokaryotes as occurred in plants. This suggests they had a more recent origin than many other algae. However, fossil evidence is scant, and only with the evolution of the diatoms themselves do the heterokonts make a serious impression on the fossil record.
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The vegetation of the park represents Sri Lanka's dry evergreen forests. Chena cultivation and grasslands surround the tank area. The community of phytoplankton in the Kaudulla tank includes blue green algae, Microcystis spp. and diatoms such as Melosira spp.. Manilkara hexandra, Chloroxylon swietenia and Vitex altissima are the dominant tree species in the forest surrounding the tank.
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These diatoms in a neritic zone meaning that they reside in shallow parts of the ocean with a depth ranging from 0 to 170 meters deep. Their temperature range is from around -1 °C to 29 °C. They can live in temperate and subtropical waters. Common distributions are the American West Coast, Australia, New Zealand, and North Atlantic Ocean.
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Albert Grunow (3 November 1826, Berlin - 17 March 1914, Berndorf, Lower Austria) was a German-Austrian chemist and phycologist. He specialized in the study of diatoms. From 1851 he worked as a chemist in a metal works factory in Berndorf. In 1857-59 he participated in the Austrian "Novara Expedition", and was tasked with analysis of its algal collections.
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This species is distributed in European waters, the Mediterranean Sea, the Sea of Azov, in the Atlantic Ocean along the Canaries and in the Indian Ocean along Madagascar. It is found in the sublittoral zone and deeper waters (up to 35 m) in often abundant numbers on red seaweeds (Laurencia, Lomentaria, Mastocarpus), collecting diatoms and detritus.
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Other pelagic prey eaten by herring includes fish eggs, larval snails, diatoms by herring larvae below , tintinnids by larvae below , molluscan larvae, menhaden larvae, krill, mysids, smaller fishes, pteropods, annelids, Calanus spp., Centropagidae, and Meganyctiphanes norvegica. Herrings, along with Atlantic cod and sprat, are the most important commercial species to humans in the Baltic Sea.Friedrich W. Köster, et al.
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The caudal peduncle is somewhat longish. In contrast to the mountain sucker, the membrane between the rays of the tail fin is pigmented. Length has been recorded up to , but less than is more typical. Also like the mountain sucker, it feeds on diatoms, other kinds of algae, and detritus, which it obtains by scraping surfaces such as rocks.
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Silicon-based life's feasibility is commonly discussed. However, it is less able than carbon to form elaborate rings and chains. Silicon in the form of silicon dioxide is used by diatoms and sea sponges to form their cell walls and skeletons. Silicon is essential for bone growth in chickens and rats and may also be essential in humans.
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Within the northwest part of New Siberia Island, these sediments grade into clays that contain fragments of marine bivalves. Directly overlying the Eocene sediments and another erosional unconformity are sands of Oligocene and Early Miocene age. They contain thin beds of silt, mud, clay, and pebbles. These sands contain fossil plants and lagoonal, swamp, and lacustrine diatoms.
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Diatoms are capable of synthesizing silica glass in vivo. Biogenic silica (bSi), also referred to as opal, biogenic opal, or amorphous opaline silica, forms one of the most widespread biogenic minerals. For example, microscopic particles of silica called phytoliths can be found in grasses and other plants. Silica is an amorphous metal oxide formed by complex inorganic polymerization processes.
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The flints that make up Littlehampton's West Beach contain quite a few fossils. The flints are formed by silica from sea sponges and diatoms from around 60 to 95 million years ago. Some of the creatures become fossilised and can be seen as patterns on the outside of the flint. These are known locally as Shepherds crowns.
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S. guntheri forage mostly during the day, though some night activity has also been recorded. These fish graze on microscopic algae, mostly diatoms and green algae growing on rocks and submerged vegetation. They occasionally take chironomid and simuliid larvae. Before grazing on a patch with dense sediment, a fish makes wiggling head-down movements to dislodge sediment.
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It lives attached to stones or shells (fragments) in between large grains of sand. Like in all brachiopods, it filters food particles, chiefly diatoms and dinoflagellates. Gwynia capsula harbors a small number of larvae inside a brood pouch, but it has separate sexes, unlike also very small and pouch brooding Argyrotheca and Joania, which are hermaphrodite.
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Circular tanks of 2–5 tonnes capacity are used to rear larvae from nauplius to mysis stage. The salinity of water is maintained at around 32‰ and pH at 8.2. Feed is not provided to nauplius as it is a non-feeding stage. The protozoea stage is supplied with a mixed culture of diatoms dominated by Chaetoceros spp.
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Laws , Otter Chaos at Rodeo Lagoon, Bay Nature, July–September 2007 The lagoon is ringed by emergent aquatic vegetation, such as willows and cattail, and has submerged aquatic vegetation like sago pondweed and widgeon grass in the shallow areas. The phytoplankton community includes diatoms, chlorophytes, flagellated protozoa, Microcystis aeruginosa, and Nodularia spumigena. Microcystis sp. and Nodularia sp.
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Researchers at TMMC have discovered that domoic acid (DA) is the causative agent responsible for illness in a great many California sea lions. DA is naturally produced by the diatom Pseudo-nitzschia. DA passes up the food chain as the diatoms are consumed by zooplankton. These zooplankton are then consumed by fish, where the toxin accumulates.
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All land plants and green algae possess two forms of this pigment: chlorophyll a and chlorophyll b. Kelps, diatoms, and other photosynthetic heterokonts contain chlorophyll c instead of b, red algae possess chlorophyll a. All chlorophylls serve as the primary means plants use to intercept light to fuel photosynthesis. Carotenoids are red, orange, or yellow tetraterpenoids.
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Nutrients such as nitrate are necessary for phytoplankton to thrive. Since the ocean’s availability of nutrients varies, diatoms must have ways to adapt under different nutrient levels to maintain healthy populations. When these nutrients are scarce, C. pseudocurvisetus can form alternative dormant life cycles to wait out the unfavorable conditions. These forms are resting spores and resting cells.
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Silicic acid is limiting to diatoms. In a single population of C. pseudocurvisetus both resting spores and resting cells may be formed, depending on the concentrations of silica. Resting cells resemble vegetative cells, except they have weakly pigmented, shrunken and fragmented chloroplasts. Resting cells and resting spores both have a lower respiratory rate and photosynthetic activity than vegetative cells.
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P. eriomerus is a filter feeder subsisting largely on diatoms which it gathers with the setae on its mouthparts. It also uses the tufts of setae on its chelipeds to sweep deposits off the surfaces of rocks for consumption. Females usually have two broods per year. The larvae are free living and form part of the zooplankton.
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Of freshwater animals, tiny choanoflagellates and needles from small sponges have been found in the lignite in Brjánslækur. Remains of water fleas have been found in Mókollsdalur and Langavatnsdalur. In a gorge above Illugastaðir in Fnjóskadalur, parts of bivalve molluscs were found which probably lived in fresh water since there is residue of plants and diatoms in the sediment.
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Mozambique tilapia are omnivorous. They can consume detritus, diatoms, invertebrates, small fry and vegetation ranging from macroalgae to rooted plants.Mook 1983Trewevas 1983 This broad diet helps the species thrive in diverse locations. Due to their robust nature, Mozambique tilapias often over-colonize the habitat around them, eventually becoming the most abundant species in a particular area.
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P. clavata is a filter feeder, the polyps extending their tentacles to catch food particles floating past. Its diet includes copepods, diatoms, dinoflagellates, ciliates, and organic carbon particles in suspension. Each colony is either male or female. Sperm is liberated into the sea by the male colonies and fertilisation occurs on the surface of the female colonies.
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Ectodus descampsii is a species of cichlid fish endemic to Lake Tanganyika in East Africa where it prefers areas with substrates of coarse sand. It feeds on micro-organisms, algae and diatoms. This species reaches a length of TL. It is also found in the aquarium trade. It is currently the only known member of its genus.
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Coscinodiscus elegans is a species of diatom in the family Coscinodiscaceae. It is found in the Gulf of Mexico.Krayesky, D. M., E. Meave del Castillo, E. Zamudio, J. N. Norris, and S. Fredericq. 2009. Diatoms (Bacillariophyta) of the Gulf of Mexico, Pp. 155–186 in Felder, D.L. and D.K. Camp (eds.), Gulf of Mexico–Origins, Waters, and Biota. Biodiversity.
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They form biosilica shells using dissolved silicon and carbon acquired from various carbon partitioning pathways. Other materials Cyclotella spp. use for cell wall biosynthesis are semiconductor metal oxides and extracellular fibers made of chitin. The primary allomorph of chitin that is found most often in diatoms is α-chitin, but Cyclotella and Thalassiosira contain the β-chitin allomorph.
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Many of these isomers differ in their orientation to their single copy sequence counterparts. The species, according to the findings, still has some prokaryotic and land plant gene clusters as well as operons. In comparison to many other diatoms and plant chloroplast studies, C. meninghiana has a diversely rearranged gene order for single copy regions in its genome.
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Stromatolites in an alkaline (pH greater than 9) freshwater lake (Salda Gölü) in southern Turkey are made of hydromagnesite precipitated by diatoms and cyanobacteria. SEM micrograph of hydromagnesite showing platy crystal morphology. Sample was collected from the hydromagnesite-magnesite playas near Atlin, British Columbia, Canada. Microbial deposition of hydromagnesite is also reported from playas in British Columbia.
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The female lays her eggs against the vegetation. The larvae hatch within three days and began to swim and feed after 6 to 7 days and reach maturity after one year. Most males are only two years old and females reach up to three years old. The species is omnivorous and eat insects, zoo plankton, green algae and diatoms.
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Reproduction is sexual, the gametes of both sexes being expelled into the water, then the free larvae attach themselves to rocks. These clams filter the sea water in order to feed on bacteria, diatoms and larvae of invertebrates. In some years, the reproductive cycle fails completely. These clams are the main food of the walrusses (Odobenus rosmarus).
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His Bachelor of Science degree was obtained in 1958 and his Doctor of Science in 1963, both from Iowa State University. His doctoral thesis was "Post- pleistocene diatoms from Lake West Okoboji, Iowa" WorldCat title entry Stoermer originally coined and used the term Anthropocene from the early 1980s to refer to the impact and evidence for the effects of human activity on the planet earth. The word was not used in general culture until it was popularized in 2000 by Nobel Prize-winning atmospheric chemist Paul Crutzen and others who regard the influence of human behavior on Earth's atmosphere in recent centuries as so significant as to constitute a new geological epoch. He is the co-author with J. P. Smol of The Diatoms Applications for the Environmental and Earth Sciences.
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Flagellated lifecycle stages are found in many groups, e.g., many green algae (zoospores and male gametes), bryophytes (male gametes), pteridophytes (male gametes), some gymnosperms (cycads and Ginkgo, as male gametes), centric diatoms (male gametes), brown algae (zoospores and gametes), oomycetes (assexual zoospores and gametes), hyphochytrids (zoospores), labyrinthulomycetes (zoospores), some apicomplexans (gametes), some radiolarians (probably gametes), foraminiferans (gametes), plasmodiophoromycetes (zoospores and gametes), myxogastrids (zoospores), metazoans (male gametes), and chytrid fungi (zoospores and gametes). Flagella or cilia are completely absent in some groups, probably due to a loss rather than being a primitive condition. The loss of cilia occurred in red algae, some green algae (Zygnematophyceae), the gymnosperms except cycads and Ginkgo, angiosperms, pennate diatoms, some apicomplexans, some amoebozoans, in the sperm of some metazoans, and in fungi (except chytrids).
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Mountain suckers are primarily herbivorous, feeding mostly on algae and diatoms, but they will eat various aquatic invertebrates as well. They feed by scraping the substrate with their mouths. Spawning occurs during late spring to early summer, when the waters are between 10.5-18.8°C. They move into smaller streams, where they spawn over gravel riffles upstream from quiet pools.
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It is a common species, occurring wherever the substrate of the littoral zone is rocky, and is especially common in crevices and rock pools and under stones. It is a nocturnal omnivore, eating many kinds of seaweed, diatoms and debris, with a particular fondness for bladder wrack (Fucus vesiculosus). L. oceanica individuals live for 2–3 years and usually breed only once.
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It was dominated by NaCl, Na-Cl-CO3 and Na-Cl-SO4, as determined from studies on diatoms; close to the inlet of the Desaguadero River the waters were less salty. When the lake dried up, it left clay and sand deposits in the Altiplano. Also, the volume of about maximum of water induced the ground beneath the lake to sink by about .
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The lake was saline. The lake received water from Lake Titicaca, but whether this contributed most of Tauca's water or only a small amount is controversial; the quantity was sufficient to influence the local climate and depress the underlying terrain with its weight. Diatoms, plants and animals developed in the lake, sometimes forming reef knolls. The duration of Lake Tauca's existence is uncertain.
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Hydrated silica is a form of silicon dioxide, which has a variable amount of water in the formula. When dissolved in water it is usually known as silicic acid. It is found in nature, as opal (which has been mined as a gemstone for centuries), and in the cell walls of diatoms. It is also manufactured for use in toothpaste.
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In cosmetics, silica is useful for its light-diffusing properties and natural absorbency. Diatomaceous earth, a mined product, has been used in food and cosmetics for centuries. It consists of the silica shells of microscopic diatoms; in a less processed form it was sold as "tooth powder". Manufactured or mined hydrated silica is used as the hard abrasive in toothpaste.
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André Fuhrmann has made contributions in Analytic philosophy, Relevance logic and Modal logic. Fuhrmann is best known for his research on "belief revision" or "theory change", a field of formal epistemology with applications for artificial intelligence and cognitive science. Fuhrmann also takes an interest in freshwater diatoms. Together with H. Lange-Bertalot he discovered, sampled and described new species in Brazil.
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Phytoplankton – such as this colony of Chaetoceros socialis – naturally give off fluorescent light as they dissipate excess solar energy that they cannot consume through photosynthesis. Chaetoceros is probably the largest genus of marine planktonic diatoms with approximately 400 species described, although many of these descriptions are no longer valid. It is often very difficult to distinguish between different Chaetoceros species.C.H. von Quillfeldt., (2001).
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George Henry Kendrick Thwaites (9 July 1812, Bristol – 11 September 1882, Kandy) was an English botanist and entomologist. Thwaites was initially an accountant and studied botany during his spare time. He was interested particularly in the lower plants such as the algae and the cryptogams. He became a recognised botanist when he showed that the diatoms are not animals, but algae.
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High f-ratio values are typically associated with productive ecosystems dominated by large, eukaryotic phytoplankton (such as diatoms) that are grazed by large zooplankton (and, in turn, by larger organisms such as fish). By contrast, low f-ratio values are generally associated with low biomass, oligotrophic food webs consisting of small, prokaryotic phytoplankton (such as Prochlorococcus) which are kept in check by microzooplankton.
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The 18S gene region has been widely used as a marker in other protist groups and Jahn et al. were the first to test the 18S gene region for diatoms barcoding. Zimmerman et al. proposed a 390–410 bp long fragment of the 1800 bp long 18S rRNA gene locus as a barcode marker for the analysis of environmental samples with HTS.
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In the next 24 hours, this layer allows the process of bacterial adhesion to occur, with both diatoms and bacteria (e.g. vibrio alginolyticus, pseudomonas putrefaciens) attaching, initiating the formation of a biofilm. By the end of the first week, the rich nutrients and ease of attachment into the biofilm allow secondary colonizers of spores of macroalgae (e.g. enteromorpha intestinalis, ulothrix) and protozoans (e.g.
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The geologic origins of Djebel Ressas and the neighboring peaks date to earlier than 100 million years ago. The surrounding region was then a vast and swampy tropical area abundant with life.Science Encyclopedia Volume II, Diatoms The large carnivorous dinosaurs Spinosaurus aegyptiacus hunted nearby in what is currently the Sahara desert in southern Tunisia.Bulletin de la Société Géologique de France; September 2002; v.
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Other examples are dinophyta and diatoms that have a cell wall that does not change during the cell cycle. During cell-growth, when the amounts of protein and carbohydrates increase, the vacuole shrinks. The outer membrane that is involved in nutrient uptake remains constant. At cell division, the daughter cells rapidly take up water, complete a new cell wall and the cycle repeats.
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Diatoms are the dominant group in the lake, particularly during the dry season episodes of deep mixing. During the rainy season, the stratified water column, with high light and lower nutrient availability, favour dominance of cyanobacteria with high numbers of phototrophic picoplankton. The actual primary production is 0.71 g C m−2 d−1 (≈ 260 g C m−2 a−1).
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The species prefers clear, running waters in rocky habitats of small and large rivers, and is also found in lakes and dams over rocky areas. It feeds on diatoms and other small algae from the rocks. It migrates upstream in masses to breed, using the mouth and broad pectoral fins to climb damp surfaces of barrier rocks and weirs in the river.
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As larve (ammocoetes), the northern brook lamprey are filter feeders; feeding primarily on detritus, zooplankton, algae, diatoms, bacteria, pollen and a host of other microorganisms as they remain burrowed in fine substrate in calm waters. The juveniles and adults have non-functional intestines and do not feed; juveniles drift for 4–6 months and the adults spawn and die shortly after spawning.
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F. antipyretica grows in large clumps and mats and provides refuge for fish eggs and fry. Numerous invertebrates shelter among the fronds; Chironomid larvae hide in the bases of the leaves and mayfly, caddisfly and stonefly larvae cling to the fronds, and in fast-flowing water black fly larvae are often present. Diatoms and other microscopic algae grow epiphytically on the fronds.
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Four-eyed fish (Anableps anableps), Trinidad Four-eyed fish spend most of their time at the surface of the water. Their diet mostly consists of terrestrial insects which are readily available at the surface, however they may consume other foods such as other invertebrates, diatoms, and small fishes. The fish will group differently depending on the species. A. anableps commonly congregates in schools.
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Many dinoflagellates are meroplanktonic, undergoing a seasonal cycle of encystment and dormancy in the benthic zone followed by excystment and reproduction in the pelagic zone before returning to the benthic zone once more. There also exist meroplanktonic diatoms; these have a seasonal resting phase below the photic zone and can be found commonly amongst the benthos of lakes and coastal zones.
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The main primary producers of the bay are eelgrass (Zostera marina, a type of seagrass), microscopic diatoms, and sea lettuce (Ulva enteromorpha, a type of macroalgae). Most of these species are found on mudflats, which account for about two-thirds of the total area of Netarts Bay.McIntire, C.D., Davis, M.W., Kentula, M.E., Whiting, M. (1983). Benthic Autotrophy in Netarts Bay, Oregon.
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Thalassiosira rotula represents the most well-studied diatom species in terms of polyunsaturated aldehyde production. Wichard et al. determined that only 30% of PUA precursor molecules remain in T. rotula within minutes of cell membrane wounding, indicating a fast rate of response by diatoms to zooplankton grazing.Wichard, Thomas, Gerecht, Andrea, Boersma, Maarten, Poulet, Serge A., Wiltshire, Karen, and Pohnert, Georg.
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Fd-GOGAT is found strictly in cyanobacteria and photosynthetic eukaryotes, and the gene is located in the chloroplast of rhodophytes and in the nucleus of vascular plants, but in both cases its product is active in the chloroplast. NADH-GOGAT is found in the nucleus of vascular plants, fungi, and diatoms, while NADPH-GOGAT is found in non-photosynthetic bacteria and archaea.
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Charophyte algae (such as Chara globularis and Chara vulgaris), diatoms, gastropods, golden algae, sponges and stromatoliths lived in the lake. Ferns and mosses colonized the margins of the crater. The lake reached maximum depths of at a minimum , at least once reaching . Such a large size, relative to its catchment, has raised the question of where this water came from.
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There are several main groups of microalgae, that differ by pigment composition, biochemical constituents, ultrastructure, and life cycle. Five groups were of primary importance to the ASP: diatoms (Class Bacillariophyceae), green algae (Class Chlorophyceae), golden- brown algae (Class Chrysophyceae), prymnesiophytes (Class Prymnesiophyceae), and the eustigmatophytes (Class Eustigmatophyceae). The blue-green algae, or cyanobacteria (Class Cyanophyceae), were also represented in some of the collections.
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Acetyl-CoA carboxylase (ACCase) is an enzyme which catalyzes a key metabolic step in the synthesis of oils in algae. The program was the first to isolate this enzyme from a diatom. The researchers discovered the transformation system for diatoms. They wanted to know if increasing the level of ACCase activity in the cells would lead to higher oil production.
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Bacteriastrum is a genus of diatoms in family Chaetocerotaceae.Tomas, C. R., Hasle G. R., Syvertsen, E. E., Steidinger, K. A., Tangen, K., Throndsen, J., Heimdal, B. R., (1997). Identifying Marine Phytoplankton, Academic Press. There are more than 30 described species in genus Bacteriastrum, but many of these are not currently accepted, and new species are still added to the genus.
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Each deposit of diatomaceous earth is different, with varying blends of pure diatomaceous earth combined with other natural clays and minerals. The diatoms in each deposit contain different amounts of silica, depending on the age of the deposit. The species of diatom may also differ among deposits. The species of diatom is dependent upon the age and paleoenvironment of the deposit.
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Water from this lake feeds Butte Lake, located to the north. Butte Lake is the sole remaining fragment of a much larger body of water filled with lava during Cinder Cone's eruptive period. Diatomite sediment, formed from the aggregation of diatoms on the lake's floor, run along the edges of the Fantastic Lava Beds and mark the margins of this former lake.
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The central stoneroller is generally herbivorous, feeding primarily on algae scraped from rocks and logs with the cartilaginous ridge on its lower jaw. Young fish feed on rotifers, filamentous algae, and microcrustacea. It also feeds on detritus, diatoms, and occasionally aquatic insects. It is classified as a grazing minnow in its feeding behavior, and large schools of these fish often feed together.
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BHL Taxonomic literature : a selective guide to botanical publications In the first edition of Die Natürlichen Pflanzenfamilien, a work by Adolf Engler and Carl Prantl, he collaborated about orchids (published in 1889). In addition to his work involving orchids, he conducted important research of diatoms, publishing the treatise "Untersuchungen über Bau und Entwicklung der Bacillariaceen (Diatomaceen)" (1871) as a result.
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The eukaryotic CRESS-DNA viruses are associated with a variety of diseases. Plant viruses in the families Geminiviridae and Nanoviridae infect economically important crops, causing significant damage to agricultural productivity. Animal viruses in Circoviridae are associated with many diseases, including respiratory illness, intestinal illness, and reproductive problems. Bacilladnaviruses, which primarily infect diatoms, are thought to have a significant role in controlling algal blooms.
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Diatoms, insects, their bodyparts and pollen have also been found in the ice. The composition of the ice may be influenced by the precipitation type. During winter, the albedo of the ice is about 80%. As reported in 2013, 1979 and 1981, there is little energy available at the top of the Quelccaya ice cap as outgoing and incoming radiation are essentially balanced.
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They are flagellated eukaryotes that combine photoautotrophy when light is available, and heterotrophy via phagocytosis. Dinoflagellates are one of the most diverse and numerous species of phytoplankton, second to diatoms. Dinoflagellates have long whip-like structures called flagella that allow them to move freely throughout the water column. They are mainly marine but can also be found in freshwater environments.
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The type species, R. amitus, has been described in Baltic plankton. It has an elongated pear shaped body, often more concave on one side than the other. A disc separates the flagellar apparatus ingestion pocket and two flagella pocket as they emerge from the cell. They have been found feeding on planktonic diatoms cytoplasm and gills of crayfish and crabs.
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The eggs are relatively large and have a double "shell", allowing the fish to spawn in rough rapids and riffles. The fast water is highly oxygenated and a highly productive zone for algae, diatoms and aquatic insect larvae and nymphs. The juvenile fish have silver bellies and a characteristic olive-green back with black spots. They gather in small shoals in favourable habitat.
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Young fish feed on surface insects. When the chisel develops (at around 0.6 inches length), they shift to scraping, making short darting movements at the substrate to dislodge whatever is on it, and sucking it in. Although they consume filamentous algae, it seems to not be digested much despite a long coiled intestine, and their primary food actually consists of diatoms.
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Colonies of Pennaria disticha consist of numerous much-branched stems up to high. The branching system is alternate. The polyps are tiny and are supported by a hydrocaulus, a fairly stiff hollow tube with a perisarc (sheath) made of chitin and protein. This is dark brown or blackish, but is often colonised by algae and diatoms giving it a muddy appearance.
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Two color morphs of this sea hare have been observed, bright green, and yellow, with characteristic black and white stripes (see Beeman 1970 for more complete description) This is a rather primitive species. It has a dorsally flattened body, it is well camouflaged, being found almost exclusively on eelgrass, Zostera marina. It grazes on epiphytes that settle on Zostera blades - sponges and diatoms.
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The Polonnaruwa meteorite is an alleged meteorite that fell on 29 December 2012 close to the city of Polonnaruwa in Sri Lanka, and recovered soon after by Chandra Wickramasinghe's team. Twelve days after the Polonnaruwa meteorite was "seen falling" to Earth, Chandra Wickramasinghe published in the online fringe science Journal of Cosmology that, after studying some electron micrographs, his team discovered fossilized diatoms (microscopic phytoplankton) inside the meteorite as well as cells similar to those found in the Red rain in Kerala that fell in 2001. In addition, his team of scientists reported in a separate article that they are certain that it is a meteorite that originated from a comet and that it also contained living diatoms. The rock is not deemed by peer scientists to be a meteorite, so it was not recorded in the international Meteoritical Society database.
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He developed the "ATM Experiment S-056 grazing incidence X-ray telescope" and obtained 25,000 solar x-ray images from Skylab, and developed the instrument that obtained the first high resolution X-ray/EUV (X-ray to extreme ultraviolet) images of the Sun ever obtained with a normal incidence multilayer X-ray telescope. He performed research on unicellular algae known as diatoms,Hoover authored the article "Those Marvelous Myriad Diatoms" published in National Geographic in June, 1979. and is noted for his discovery of microbial extremophiles from places such as Mono Lake, deep Lake Vostok ice cores, deep sea hydrothermal vents, and the living pleistocene bacterium Carnobacterium pleistocenium isolated from the 32,000-year-old permafrost from Fox Tunnel in Alaska. He organized and co-chaired the NASA/NATO/INTAS sponsored 'Astrobiology Advanced Study Institute' that was held in Chania, Crete in 2002.
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Her father taught her the basics of science in his laboratory, where he studied plankton; this formative experience sparked Cleve's interest in diatoms. She obtained her baccalaureate at sixteen. She matriculated at Uppsala University in the fall of 1891 to study natural science; she graduated with a bachelor's degree in January 1894. She then was hired as an assistant chemistry professor at the progressive Stockholm University.
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Before 1978, scientists hypothesized that diatoms dominated plankton populations in the NPSG. The primary consumers were expected to be relatively large mesozooplankton. It is now well known that most of the algae in the NPSG are actually bacteria (unicellular organisms), dominated by cyanobacteria, or blue-green algae. These simple organisms make up the majority of the standing stock of photosynthesizing marine life in this ecosystem.
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These conditions are only rarely present and once one of the needed conditions fails, the Pacific returns to its normal state. Often, the line collapses because of the currents returning to normal and the cool waters return to the depths, causing the diatoms to die out (they need the difference in ocean temperature to flourish), the turbulence to cease and the fish to move elsewhere.
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Based on pollen data, sagebrush grassland occurred around Lake Estancia, with pine- spruce woodland in the Manzano Mountains. Increased water availability probably allowed grazing animals to thrive around the lake. Various fossils have been found in lake deposits, including algae, diatoms, foraminifera, gastropods, ostracods and pelecypods. During desiccation phases, molluscs disappeared and charophyte, ditch grass, Ruppia and stonewort grew in the wet soils and saltwater.
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The diatom endosymbiont's nucleus is present, but it probably can't be called a nucleomorph because it shows no sign of genome reduction, and might have even been expanded. Diatoms have been engulfed by dinoflagellates at least three times. The diatom endosymbiont is bounded by a single membrane, inside it are chloroplasts with four membranes. Like the diatom endosymbiont's diatom ancestor, the chloroplasts have triplet thylakoids and pyrenoids.
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The gut forms a straight tube; its digestive efficiency is not very high and therefore a lot of carbon is still present in the feces. Antarctic Krill (E.superba) primarily has chitinolytic enzymes in the stomach and mid-gut to break down chitinous spines on diatoms, additional enzymes can vary due to its expansive diet. In aquaria, krill have been observed to eat each other.
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Other carbonate grains composing limestones are ooids, peloids, intraclasts, and extraclasts. Limestone often contains variable amounts of silica in the form of chert (chalcedony, flint, jasper, etc.) or siliceous skeletal fragment (sponge spicules, diatoms, radiolarians), and travertine (a precipitate of calcite and aragonite). Secondary calcite may be deposited by supersaturated meteoric waters (groundwater that precipitates the material in caves). This produces speleothems, such as stalagmites and stalactites.
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Effect of eutrophication on marine benthic life The main food sources for the benthos are algae and organic runoff from land. The depth of water, temperature and salinity, and type of local substrate all affect what benthos is present. In coastal waters and other places where light reaches the bottom, benthic photosynthesizing diatoms can proliferate. Filter feeders, such as sponges and bivalves, dominate hard, sandy bottoms.
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Block glaciers developed on Mouskorbe, the largest of which is long on the south flank and ends at elevation. There is widespread evidence of nivation landforms on Mouskorbe above and especially above . Presently, precipitation at Mouskorbe is about . Former lakes in Tarso Emi Chi were inhabited by snails such as Euconulus fulvus, Limnea trunculata, Succinea pfeifferi and Zonitoides nitidus, as well as by diatoms, grasses and reeds.
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Herman Melville called the blue whale "sulphur bottom" in his novel Moby Dick due to the accumulation of diatoms creating a yellowish appearance on their pale underside. The name rorqual comes from the Norwegian word rørhval, a reference to the whale’s throat grooves, which are an elastic structure of blubber and muscle also known as the ventral grove blubber extending from the chin to the umbilicus.
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The Cretaceous-Tertiary boundary was a time of global mass extinction, commonly referred to as the K-T mass extinction. While most organisms were disappearing, marine siliceous organisms were thriving in the early Paleocene seas. One such example occurred in the waters near Marlborough, New Zealand. Paleo-ooze deposits indicate that there was a rapid growth of both diatoms and radiolarians at this time.
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It can also live in waters as cold as and as warm as . Other environmental conditions and their ranges include salinity (18–36 pps), oxygen (1–9 mL/L), nitrate (0–45 μmol/L), phosphate (0–3 μmol/L) and silicate (1–181 μmol/L) levels. Calanus finmarchicus primarily feeds on different forms of phytoplankton. This includes diatoms, dinoflagellates, ciliates, and other photosynthetic marine organisms.
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Because C. adunca filter feeds, it uses cilia to bring the small organisms over its gills where it filters out the bacteria from the water using mucus made by the gill cells. Once caught by the mucus, the cilia, known as ciliary action, carries the organisms to the mouth along the dorsal surface. The organisms that C. adunca filters for are diatoms, dinoflagellates, phytoplankton, bacteria, etc.
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The expansion of grassland biomes and the evolutionary radiation of grasses during the Miocene is believed to have increased the flux of soluble silicon to the oceans, and it has been argued that this promoted the diatoms during the Cenozoic era. Recent work suggests that diatom success is decoupled from the evolution of grasses, although both diatom and grassland diversity increased strongly from the middle Miocene.
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Decomposition and decay of diatoms leads to organic and inorganic (in the form of silicates) sediment, the inorganic component of which can lead to a method of analyzing past marine environments by corings of ocean floors or bay muds, since the inorganic matter is embedded in deposition of clays and silts and forms a permanent geological record of such marine strata (see siliceous ooze).
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Cerithideopsis californica lives in salt-marsh dominated estuaries. The snails primarily feed on benthic diatoms. Throughout its range in California, these snails grow and reproduce from spring through fall (March–October) and cease growth and reproduction during the winter (November–February). Maximum longevity for these snails is at least 6–10 years, and this appears to be the case for uninfected as well as infected snails.
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Calcareous is used as an adjectival term applied to anatomical structures which are made primarily of calcium carbonate, in animals such as gastropods, i.e., snails, specifically about such structures as the operculum, the clausilium, and the love dart. The term also applies to the calcium carbonate tests of often more or less microscopic Foraminifera. Not all tests are calcareous; diatoms and radiolaria have siliceous tests.
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The tadpoles feed on periphyton, filamentous algae, diatoms, and pollen in or on the surface of the water. They feed using suction, and a beak-like structure that helps scrape vegetation off surfaces. The species attracts mates using a choral song. Males call to females as loudly as possible and produce a croak so loud that they sound as though they are produced by multiple males.
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The Araucanian herring, Clupea bentincki, is a fish species in the family Clupeidae. It is an epipelagic fish, silvery below and dark blue above, which schools in coastal waters off the west coast of South America. There it filter feeds on smaller plankton such as diatoms. It reaches sexual maturity when it is about 10 centimetres long, and is a pelagic spawner, spawning between June and November.
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Alticorpus peterdaviesi is a species of fish in the family Cichlidae. It is endemic to Lake Malawi. It is found in the southern part of the lake, in areas where the substrate consists of "diatom ooze" and diatoms probably form the major part of its diet. The specific name honours Peter Davies, an exporter of live fish from Lake Malawi who provided great assistance to the authors.
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The pungu (Pungu maclareni) is a species of cichlid endemic to Lake Barombi Mbo in Cameroon where it prefers shallow waters of about in depth. It feeds on invertebrates, sponges, diatoms and macrophytes. This species can reach a length of SL. It is currently the only known member of its genus, but it is very close to Sarotherodon.Martin; Cutler; Friel; Touokong; Coop; and Wainwright (2015).
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The Santa Ana sucker (Catostomus santaanae) is a freshwater ray-finned fish, endemic to California. It is closely related to the mountain sucker and has dark grey upper parts and silvery underparts. It grows to a maximum length of , but most adults are much smaller than this. It feeds on algae, diatoms and detritus on the floor of shallow streams with sand, gravel or cobble bottoms.
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The Otjikoto tilapia mostly feeds on algae, including diatoms, but it is an opportunistic omnivore and will also take invertebrates. The Otjikoto tilapia can reach a total length of up to . When breeding, the underparts become black. Otherwise it is very variable in coloration, occurring in five main morphs, which are not sex-limited: olive, olive striped, dark blue, blue striped and light blue.
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Turtle grass and other seagrasses form meadows which are important habitats and feeding grounds. Associated seagrass species include Halophila engelmannii and Syringodium filiforme. Many epiphytes grow on the grasses, and algae, diatoms and bacterial films cover the surface of the leaf blades. The grass is eaten by turtles, herbivorous parrotfish, surgeonfish, and sea urchins, while the leaf surface films are a food source for many small invertebrates.
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Solid sea ice is permeated with channels filled with salty brine. These briny channels and the sea ice itself have its ecology, referred to as "sympagic ecology". Residents of temperate or tropical climates often assume, mistakenly, that ice and snow are devoid of life. In fact, a number of varieties of algae such as diatoms engage in photosynthesis in arctic and alpine regions of Earth.
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A 2012 study deposited iron fertilizer in an eddy near Antarctica. The resulting algal bloom sent a significant amount of carbon into the deep ocean, where it was expected to remain for centuries to millennia. The eddy was chosen because it offered a largely self-contained test system. As of day 24, nutrients, including nitrogen, phosphorus and silicic acid that diatoms use to construct their shells, declined.
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Most commonly, iron was available as an inorganic source to phytoplankton; however, organic forms of iron can also be used by specific diatoms which use a process of surface reductase mechanism. Uptake of iron by phytoplankton leads to lowest iron concentrations in surface seawater. Remineralization occurs when the sinking phytoplankton are degraded by zooplankton and bacteria. Upwelling recycles iron and causes higher deep water iron concentrations.
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In marine environments, bacterial endosymbionts have more recently been discovered. These endosymbiotic relationships are especially prevalent in oligotrophic or nutrient-poor regions of the ocean like that of the North Atlantic. In these oligotrophic waters, cell growth of larger phytoplankton like that of diatoms is limited by low nitrate concentrations. Endosymbiotic bacteria fix nitrogen for their diatom hosts and in turn receive organic carbon from photosynthesis.
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The grooved mullet is found in brackish and marine waters in estuaries and coastal shallows. It is a very adaptable species and has been recorded in both freshwater and hypersaline environments. Spawning occurs offshore and the fry move inshore while feeding on zooplankton. The adults sift food such as organic detritus, blue-green algae, diatoms, gastropods, and foraminifera from the substrate, usually coarse sand.
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The site was designated an ASPA for the great scientific value of its unusual biodiversity, including many species of plants, birds, and invertebrates. The unique topography, with the abundance and diversity of the vegetation, have created favourable conditions for the formation of numerous microhabitats. The extensive coastal vegetation includes lichens, mosses and grasses, with Antarctic hairgrass and Antarctic pearlwort. The mineral soils contain cyanobacteria and diatoms.
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Diatoms have the ability to enter two distinct resting stages to overcome periods of stress. A resting spore has a great capacity to survive over extended periods of nutrient deprivation. To avoid low nutrient concentrations during stratification, the resting spores can settle to the bottom where the nutrient concentration is higher. A resting cell is better able to rapidly respond when nutrients become available again.
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Themisto are obligate carnivores. Themisto gaudichaudii has been found to feed opportunistically on copepods and chaetognaths, as juveniles also on diatoms. Themisto are important prey in many food webs. For example, Themisto gaudichaudii reaches high densities (up to 61 individuals/m3) in Kerguelen waters and is a major food item for blue petrels, thin-billed prions, Antarctic prions, common diving petrels, and southern rockhopper penguins.
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Peruvian opal (also called blue opal) is a semi-opaque to opaque blue-green stone found in Peru, which is often cut to include the matrix in the more opaque stones. It does not display a play of color. Blue opal also comes from Oregon and Idaho in the Owyhee region, as well as from Nevada around the Virgin Valley. Opal is also formed by diatoms.
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Algae communities are less diverse in acidic water containing high zinc concentration, and mine drainage stress decrease their primary production. Diatoms' community is greatly modified by any chemical change, pH phytoplankton assemblage, and high metal concentration diminishes the abundance of planktonic species. Some diatom species may grow in high-metal-concentration sediments. In sediments close to the surface, cysts suffer from corrosion and heavy coating.
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Marine diatoms are among the many planktonic organisms that paradoxically appear to flout the competitive exclusion principle. In aquatic biology, the paradox of the plankton describes the situation in which a limited range of resources supports an unexpectedly wide range of plankton species, apparently flouting the competitive exclusion principle which holds that when two species compete for the same resource, one will be driven to extinction.
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The latter can also act as filters for filter feeding during phytoplankton blooms. The grazing activity of this shrimp is essential in maintaining the integrity of the crust, an actively growing matrix of plants, bacteria, diatoms, protozoans, and underlying siliceous and carbonate materials. Halocaridina is well adapted to the epigeal-hypogeal habitat in the pools. It reproduces in the subterranean portion of the habitat.
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Red tide in a harbor, Japan Red tide is a common name for algal blooms, which are large concentrations of aquatic microorganisms, such as protozoans and unicellular algae (e.g. dinoflagellates and diatoms). The upwelling of nutrients from the sea floor, often following massive storms, provides for the algae and triggers bloom events. Harmful algal blooms can occur worldwide, and natural cycles can vary regionally.
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Pakistan Journal of Scientific and Industrial Research. Vol. 27, No. 4, pp.199-205. The pollutants along with other environmental perturbations have also proved to be harmful to the biodiversity of marine species along Karachi Fish HarbourS Saifullah and M Moazzam (1978) Species Composition and Seasonal Occurrence of Centric Diatoms in a Polluted Marine Environment. Pakistan Journal of Botany Vol 10, No 1, p 53-64, June.
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Other hydroxyprolines also exist in nature. The most notable ones are 2,3-cis-, 3,4-trans-, and 3,4-dihydroxyproline, which occurs in diatom cell walls and are postulated to have a role in silica deposition. Hydroxyproline is also found in the walls of oomycetes, fungus-like protists related to diatoms. (2S,4S)-cis-4-Hydroxyproline is found in the toxic cyclic peptides from Amanita mushrooms (e.g.
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P. psammophila is a filter feeder and the lophophore is used in both feeding and respiration. It is orientated so that it faces the prevailing water current. Cilia on the inside of the tentacles create a feeding current and draw in particles. The diet consists of diatoms, microalgae, flagellates, invertebrate larvae and detritus and these are caught and transported to the mouth by the cilia.
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17(1): 1-139. Brébisson shares the credit of discovering the genus with Friedrich Traugott Kützing, a German pharmacist, botanist, and phycologist. This is in spite of the fact that neither one of these scientists ever worked together or even came in contact with one another. Kützing was a pioneer in microbial science, demonstrating the difference between diatoms and desmids in a German research paper in 1833.
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Today they still occur in the Owens River system. When Lake Panamint existed, California voles used the rivers reaching to and from the lake to propagate across the desert. Ostracods also lived in the lake waters, including Candona, Cyprideis and Limnocythere species. During shallow water periods, foraminifera also populated the lake, and the presence of diatoms and other planktonic fossils was reported already in the 1950s.
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Longnose shiners also eat various plant materials, such as seeds of various sedges, diatoms, desmids, filamentous algae, and aquatic fungi. With increasing size, longnose shiners can have a more diverse diet, and have been found include mayfly larvae in their diets.Keplinger, B. 2007. An Experimental Study of Vertical Habitat Use and Habitat Shifts in Single-species and Mixed-species Shoals of Native and Nonnative Congeneric Cyprinids.
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In recent years, the effect of reverse weathering on biogenic silica has been of great interest in quantifying the silica cycle. During weathering, dissolved silica is delivered to oceans through glacial runoff and riverine inputs. This dissolved silica is taken up by a multitude of marine organisms, such as diatoms, and is used to create protective shells. When these organisms die, they sink through the water column.
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77 About 600 species of planktonic algae are known in the Sea of Azov.Kostianoy, p. 76 The number of species is dominated by diatoms and green algae; blue-green algae and pyrophites are significant, and euglena and yellow-green algae form only 5% of the species. Green algae are mostly responsible for the colour of the sea in the satellite images (see photos above).
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Marine primary producers — plants and microscopic organisms in the plankton — are widespread and very essential for the ecosystem. It has been estimated that half of the world's oxygen is produced by phytoplankton. About 45 percent of the sea's primary production of living material is contributed by diatoms. Much larger algae, commonly known as seaweeds, are important locally; Sargassum forms floating drifts, while kelp form seabed forests.
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Temora longicornis makes daily vertical migrations, spending the day near the seabed and the night near the surface. Males can swim faster than females, and 3D tracking has shown that males can follow a detectable trail left by females. Sometimes they follow it in the wrong direction. This copepod is an omnivore; diatoms are a major part of the diet and phytoplankton is also grazed.
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This has been observed in aquatic yeasts, cyanobacteria, marine dinoflagellates and some Antarctic diatoms. When MAAs absorb UV light the energy is dissipated as heat. UV-B photoreceptors have been identified in cyanobacteria as the molecules responsible for the UV light induced responses, including synthesis of MAAs. An MAA known as palythine, derived from seaweed, has been found to protect human skin cells from UV radiation even in low concentrations.
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Cadmium use is generally decreasing because it is toxic (it is specifically listed in the European Restriction of Hazardous Substances Directive) and nickel-cadmium batteries have been replaced with nickel-metal hydride and lithium-ion batteries. One of its few new uses is in cadmium telluride solar panels. Although cadmium has no known biological function in higher organisms, a cadmium-dependent carbonic anhydrase has been found in marine diatoms.
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It also produces fecal strings that still contain significant amounts of carbon and, glass shells of the diatoms. Both are heavy and sink very fast into the abyss. This process is called the biological pump. As the waters around Antarctica are very deep (), they act as a carbon dioxide sink: this process exports large quantities of carbon (fixed carbon dioxide, CO2) from the biosphere and sequesters it for about 1,000 years.
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The exact dietary requirements of crinoids have been little researched but in the laboratory they can be fed with diatoms. Basket stars are suspension feeders, raising their branched arms to collect zooplankton, while brittle stars use several methods of feeding, though usually one predominates. Some are suspension feeders, securing food particles with mucus strands, spines or tube feet on their raised arms. Others are scavengers and feeders on detritus.
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Using benthic diatoms through a method of next-generation sequencing approach to river biomonitoring revealed a good potential in it. Many studies have shown that metabarcoding and HTS (high-throughput sequencing) can be utilized to estimate the quality status and diversity in freshwaters. As part of the Environment Agency, Kelly et al. has developed a DNA-based metabarcoding approach to assess diatom communities in rivers for the UK. Vasselon et al.
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In contrast, most other algae (e.g. brown algae/diatoms, haptophytes, dinoflagellates, and euglenids) not only have different pigments but also have chloroplasts with three or four surrounding membranes. They are not close relatives of the Archaeplastida, presumably having acquired chloroplasts separately from ingested or symbiotic green and red algae. They are thus not included in even the broadest modern definition of the plant kingdom, although they were in the past.
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The lake is polymictic, meaning that the water in the lake is usually layered but mixes over several times in the year. In sediments remnants of characeae, diatoms, ostracods and Ruppia have been found; today only one ostracod species persists in the lake. Flamingos exist in the area and the lake is an important site for birds. The watershed of Laguna del Negro Francisco covers a surface area of .
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These mixotrophic foraminifers are particularly common in nutrient-poor oceanic waters.Advances in Microbial Ecology, Volum 11 Some forams are kleptoplastic, retaining chloroplasts from ingested algae to conduct photosynthesis. Most foraminifera are heterotrophic, consuming smaller organisms and organic matter; some smaller species are specialised feeders on phytodetritus, while others specialise in consuming diatoms. Some benthic forams construct feeding cysts, using the pseuodopodia to encyst themselves inside of sediment and organic particles.
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The northern redbelly dace feeds mainly on filamentous algae and diatoms, but also zooplankton and aquatic insect larvae. Their predators consist of other fish, kingfishers and water fowl especially mergansers. In small lakes where no piscivores live, the northern redbelly dace fills the niche of a planktivore. However, in larger lakes, it is restricted to the vegetation mats by shore where it must compete with other minnows for food.
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Lustrin A is an insoluble protein used in the production of a nacreous layer in bivalve molluscs. It contributes to the properties of the nacreous layer, imparting resistance to cracking and elasticity. This is accomplished by its structure; it consists of many spring-like units which can expand when the shell is under extensional pressure. Its structure is similar to that of proteins involved in silica deposition in diatoms.
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This species consumes a varied diet of plant, animal, protist, and algal material. It has been noted to consume filamentous cyanobacteria, diatoms, brown and red algaes such as seaweeds, seagrass, forams, hydrozoans, bryozoans, nematodes, bivalves, gastropods, crustaceans, and tunicates. The larger part of its diet is composed of brown and red algae, tunicates, hydrozoans of the genus Eudendrium and bryozoans of the genus Crisia.Mazariegos-Villarreal, A., et al. (2013).
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Algae, a diverse group of non-plant photosynthetic organisms, are in general poorly known in Madagascar. A review of freshwater diatoms listed 134 species; most of them have been described from fossil deposits and it is unknown if they have become extinct. It is assumed that Madagascar harbours a rich endemic diatom flora. Diatom deposits from lake sediments have been used to reconstruct paleoclimatic variations on the island.
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Indian oil sardine The Indian oil sardine (Sardinella longiceps) is a species of ray-finned fish in the genus Sardinella. It is one of the two most important commercial fishes in India (with the mackerel). The Indian oil sardine is one of the more regionally limited species of Sardinella and can be found in the northern regions of the Indian Ocean. These fish feed on phytoplankton (diatoms) and zooplankton (copepods).
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Chlorophyll is the primary pigment in plants; it is a chlorin that absorbs yellow and blue wavelengths of light while reflecting green. It is the presence and relative abundance of chlorophyll that gives plants their green color. Green algae and plants possess two forms of this pigment: chlorophyll a and chlorophyll b. Kelps, diatoms, and other photosynthetic heterokonts contain chlorophyll c instead of b, while red algae possess only chlorophyll a.
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Journal of Morphology, 273 (12) 1353-1366 , DOI: 10.1002/jmor.20063 An additional ectosymbiotic example of commensalism is the relationship between small sessile organisms and echinoids in the Southern ocean, where the echinoids provide substrate for the small organisms to grow and the echinoids remain unaffected. Branchiobdellid annelids are mutualistic parasites. They will attach to a signal crayfish and feed on diatoms, bacteria, and protozoans that accumulate on the exoskeleton.
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During breeding, the female attempts to pick them up with her mouth and this helps the male in fertilizing the female's eggs, already in her mouth. O. karongae mainly feeds on phytoplankton, including diatoms. The lepidophagous cichlid Corematodus shiranus is an aggressive mimic of chambo in both color pattern and swimming mode. It is, therefore, able to approach unsuspecting schools of chambo and rapidly take a mouthful of scales or fin.
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Bituminous outcrop of the Puy de la Poix, Clermont-Ferrand, France The majority of asphalt used commercially is obtained from petroleum. Nonetheless, large amounts of asphalt occur in concentrated form in nature. Naturally occurring deposits of bitumen are formed from the remains of ancient, microscopic algae (diatoms) and other once-living things. These remains were deposited in the mud on the bottom of the ocean or lake where the organisms lived.
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Neither are diatoms known to be toxic, at least to humans. In freshwater ecosystems, algal blooms are most commonly caused by high levels of nutrients (eutrophication). The blooms can look like foam, scum or mats or like paint floating on the surface of the water, but they are not always visible. Nor are the blooms always green; they can be blue, and some cyanobacteria species are coloured brownish-red.
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During summers phytoplankton are dominated by cyanobacteria and occasionally diatoms, most commonly Aphanizomenon cf gracile but also Pseudanabaena limnetica, Planktolyngbya sp. and various species of Anabaena, of whom only Aphanizomenon is potentially poisonous and Anabaena frequently causes algal bloom. Carapace flagellates such as Ceratium hirundinella and various dinoflagellates, are few but important to the lake's biomass. Various rotifers are common zooplankton but cyclopoid copepods can also be found.
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Oreochromis mortimeri is a schooling species which is predominantly diurnal. It is also tolerant of higher salinities. Its diet largely consists of filamentous algae and diatoms, and also includes some vascular plants, Dipteran larvae, other insects, cladocerans, copepods, shrimps, annelids and molluscs. The male makes a saucer-shaped depression with a raised mound in the middle as a nest situated within a breeding arena in water less than in depth.
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Under experimental conditions of total submersion growth is faster and more nearly resemble growth rates of Semibalanus balanoides and Balanus crenatus. This may be because these barnacles, being always under water, have a greater continuity of food supply. There is a wide variation in rate of growth and the factors affecting it include currents and nutrient content. A scarcity of diatoms in mid-summer may slow growth at this time.
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Spirulina occurs in the large lake, and Melosira and Nitzscia diatoms have been identified in the small lake. The copepod Eucyclops gibsoni has been encountered in the small lake. Among the rotifers are Brachionus dimidiatus, Brachionus plicatilis, Hexarthra jenkinae and Lecane bulla, some of which also occur in the smaller lake. Ephedra flies are widespread around the large lake, and other insects were collected on the small lake.
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Conger was born in 1897. His specialty was the study of diatoms, which are common components of phytoplankton. He worked with Albert Mann (1853–1935), who was also a diatomist, at Carnegie Institution for Science in Washington, D.C.. He became a member of the Carnegie Institution and worked as Mann's assistant in the lab in 1922. After Mann died, Conger served as Research Associate at the CIS from 1935–1943.
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They are fed high quality microalgae and diatoms and grow fast. At metamorphosis the juveniles may be allowed to settle on PVC sheets or pipes, or crushed shell. In some cases, they continue their development in "upwelling culture" in large tanks of moving water rather than being allowed to settle on the bottom. They then may be transferred to transitional, nursery beds before being moved to their final rearing quarters.
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Amnesic shellfish poisoning (ASP) was first reported in eastern Canada in 1987. It is caused by the substance domoic acid found in certain diatoms of the genus Pseudo-nitzschia. Bivalves can become toxic when they filter these microalgae out of the water. Domoic acid is a low-molecular weight amino acid that is able to destroy brain cells causing memory loss, gastroenteritis, long-term neurological problems or death.
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It consists of a central, viscous granular proteinaceous core surrounded by tightly packed minute plates of starch. There is substantial diversity in pyrenoid morphology and ultrastructure between algal species. In the unicellular red alga Porphyridium purpureum and in the green alga Chlamydomonas reinhardtii, there is a single highly conspicuous pyrenoid in a single chloroplast, visible using light microscopy. By contrast, in diatoms and dinoflagellates, there can be multiple pyrenoids.
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Since this event, no additional deaths have been attributed to ASP, though the prevalence of toxic diatoms and DA has increased worldwide. This anomaly is likely due to increased awareness of harmful algal blooms (HABs) and their implications for human and ecosystem health. Blooms have since been characterized in coastal waters and the open-ocean worldwide and have been linked to increasing marine nutrient concentrations, warming ocean temperatures, and bacterial interactions.
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Zavrelia is a genus of European non-biting midges in the subfamily Chironominae of the bloodworm family Chironomidae. Species of the genus are small to minute chironomids, which are recorded from both continents of the northern hemisphere. All known larvae of Zavrelia construct small, straight transportable cases of sand, silt, detritus and sometimes diatoms that function as retreats until the mature pupa swims to the surface prior to its adult emergence.
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Despite the suggestion in some aquarium literature that the species feeds on worms, crustaceans, and insects, analysis of the stomach contents of wild P. pulcher suggests this is incorrect. A study by Nwadiaro (1985) of 161 individuals showed that the main food items were diatoms, green algae, pieces of higher plants, along with blue-green algae. Invertebrates, though consumed, were found to be relatively uncommon food items for wild fish.
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Diatoms are a form of algae that, when they die, often form layers at the bottoms of lakes, bays, or oceans. Their cell walls are made up of hydrated silicon dioxide which gives them structural coloration and therefore the appearance of tiny opals when viewed under a microscope. These cell walls or "tests" form the “grains” for the diatomaceous earth. This sedimentary rock is white, opaque, and chalky in texture.
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The BCCM collections contain more than 269.000 different resources. Micro-organisms are an important raw material in biotechnology. The properties of bacteria, fungi, yeasts and diatoms are used in countless industrial applications and processes. Consider, for example, fermentation processes and the use of probiotics in foods, the production of antibiotics in medicine, the use of microorganisms as growth promoting elements in agriculture, as bioremediators on polluted sites, etc.
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Stichopus chloronotus is a detritivore and sifts through the sediment on the seabed with its tentacles and feeds on detritus and other organic matter including plant and animal remains, bacteria, protozoa, diatoms and faeces. In the process it swallows a lot of sand and plays an important part in churning up and aerating the seabed.Marine Biology Papers, Volume 19 Carnegie Institution of Washington. Tortugas Laboratory, Carnegie Institution of Washington.
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Cell division in eukaryote is much more complicated than procaryote. Depending upon chromosomal number reduced or not; Eukaryotic cell divisions can be classified as Mitosis (equational division) and Meiosis (reductional division). A premitive form of cell division is also found which is called amitosis. The amitotic or mitotic cell division is more atypical and diverse in the various groups of organisms such as protists (namely diatoms, dinoflagellates etc) and fungi.
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Ernst Haeckel, in his 1866 Generelle Morphologie der Organismen, asserted that all living things were monophyletic (had a single evolutionary origin), being divided into plants, protista, and animals. His protista were divided into moneres, protoplasts, flagellates, diatoms, myxomycetes, myxocystodes, rhizopods, and sponges. His animals were divided into groups with distinct body plans: he named these phyla. Haeckel's animal phyla were coelenterates, echinoderms, and (following Cuvier) articulates, molluscs, and vertebrates.
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This species has shown a preference however for slow currents in their habitats (Lotic ecosystem), which will provide a constant supply of food. Their primary food sources are diatoms and other phytoplankton. S. corneum are sensitive to high pollution levels, particularly organic pollutants which foul the water, preventing the clams from effective feeding. As such, they are a bioindicator species whose presence may demonstrate that the water is relatively unpolluted.
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As shown on this turtle grass, many epiphytes can grow on the leaf blades of grasses, and algae, diatoms and bacterial films can cover the surface. The grass is eaten by turtles, herbivorous parrotfish, surgeonfish, and sea urchins, while the leaf surface films are a food source for many small invertebrates. Seagrass meadows are one of the more important ecosystems. Seagrasses also cleanse the water of excess nutrients and toxic pollutants.
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Chytridiomycota, the dominant parasitic fungal organism in Arctic waters, take advantage of phytoplankton blooms in brine channels caused by warming temperatures and increased light penetration through the ice. These fungi parasitize diatoms, thereby controlling algal blooms and recycling carbon back into the microbial food web. Arctic blooms also provide conducive environments for other parasitic fungi. Light levels and seasonal factors, such as temperature and salinity, also control chytrid activity independently of phytoplankton populations.
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A series of boreholes have been drilled into the marsh which found up to of unconsolidated sedimentary material over weathered bedrock. Material from the Holocene was found. From these deposits paleoenvironmental information can be examined which include particle sizes, stratigraphy, pollen and diatoms. Evidence from the pollen was used to reconstruct the type of vegetation in the lower organic-rich horizons and samples sent to the Godwin Laboratory, University of Cambridge, for radiocarbon dating.
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Its population on New Caledonia was estimated at less than 400 individuals, but it is now thought to have been extirpated from that island, it remains common on Vanuatu. Rhyacichthys guilberti occurs in coastal streams with a relatively steep gradient set in hilly or mountainous terrain. It feeds on algae and diatoms on rocks and stones. holding on in the fast current using its broadened pelvic and pectoral fins and its compressed head and snout.
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The Chinese sturgeon is a critically endangered species native to China. It is largely dispersed over the main streams of the Yangtze River and coastal regions of Qiantang River, Minjiang River, and Pearl River. The adults are predators that consume any aquatic animal that can be swallowed, while the young feed on aquatic insects, larvae, diatoms, and humic substances. In the 1970s, an estimated 2,000 Chinese sturgeon spawned in the Yangtze River every year.
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L. scabra lives on the shoreline often above high water mark in the splash zone. When the rock is wet it moves about and uses its radula to rasp microscopic algae and diatoms off the rock surface. Over time, using the scalloped edge of its shell, it grinds a groove in a rock until the shell makes a perfect fit. This enables it to remain alive under conditions that would otherwise cause desiccation.
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S. lamperti is very common on coral reefs, both on the exposed and the inner slopes. It is a detrivore that specifically feeds on or around living sponges of the Ianthella basta species. It appears to require the nutrients provided by this particular sponge to thrive, as it ingests microscopic organic particles such as diatoms and also substances exuded from the surface of its host sponge.Hammond, L. S., and C. R. Wilkinson. 1989.
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Like its cousins, dendraster is a suspension feeder which feeds on crustacean larvae, small copepods, diatoms, plankton, and detritus. Adult sand dollars move mainly by waving their spines, while juveniles use their tube feet. The tube feet along the petalidium are larger and are used for respiration while tube feet elsewhere on the body are smaller and are used for feeding and locomotion. They frequently move around if they are lying flat.
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A centric diatom, magnified x150 Siliceous ooze is a type of biogenic pelagic sediment located on the deep ocean floor. Siliceous oozes are the least common of the deep sea sediments, and make up approximately 15% of the ocean floor. Oozes are defined as sediments which contain at least 30% skeletal remains of pelagic microorganisms. Siliceous oozes are largely composed of the silica based skeletons of microscopic marine organisms such as diatoms and radiolarians.
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The Burubatial Formation, located in the West Balkhash region of Kazakhstan, is the oldest known abyssal biogenic deposit. The Burubaital Formation is primarily composed of chert which was formed over a period of 15 million years (late Cambrian-middle Ordovician). It is likely that these deposits were formed in an upwelling region in subequatorial latitudes. The Burubaital Formation is largely composed of radiolarites, as diatoms had yet to evolve at the time of its formation.
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In marine and freshwater environments, gastrotrichs form part of the benthic community. They are detritivores and are microphagous, sucking dead or living organic material, diatoms, bacteria and small protozoa into their mouths by the muscular action of the pharynx. They are themselves eaten by turbellarians and other small macrofauna. Like many microscopic animals, gastrotrich locomotion is primarily powered by hydrostatics, but movement occurs through different methods in different members of the group.
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Individual pseudopods characteristically have small granules streaming in both directions. Foraminifera are unique in having granuloreticulose pseudopodia; that is, their pseudopodia appear granular under the microscope; these pseudopodia are often elongate and may split and rejoin each other. These can be extended and retracted to suit the needs of the cell. The pseudopods are used for locomotion, anchoring, excretion, test construction and in capturing food, which consists of small organisms such as diatoms or bacteria.
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Brown algae, most specifically kelps, create underwater "forest" habitats for many marine creatures, and provide a large portion of the diet of coastal communities. Chromalveolates also provide many products that we use. The algin in brown algae is used as a food thickener, most famously in ice cream. The siliceous shells of diatoms have many uses, such as in reflective paint, in toothpaste, or as a filter, in what is known as diatomaceous earth.
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Cafeteria roenbergensis is a small bacterivorous marine flagellate. It was discovered by Danish marine ecologist Tom Fenchel and named by him and taxonomist David J. Patterson in 1988. It is in one of three genera of bicosoecids, and the first discovered of two known Cafeteria species. Bicosoecids belong to a broad group, the stramenopiles, that includes diatoms, brown and golden algae collectively known as Heterokonta, protozoa such as opalinids and actinophryid heliozoa, and oomycete fungi.
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The shells of testate amoebae may be composed of various substances, including calcium, silica, chitin, or agglutinations of found materials like small grains of sand and the frustules of diatoms. testate amoeba Difflugia acuminata. To regulate osmotic pressure, most freshwater amoebae have a contractile vacuole which expels excess water from the cell. This organelle is necessary because freshwater has a lower concentration of solutes (such as salt) than the amoeba's own internal fluids (cytosol).
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Asterina phylactica feeds on the film of bacteria and diatoms that exists on the surface of rocks. To do this it everts its stomach and presses it against the rock before secreting digestive enzymes. In their first year, individuals of Asterina phylactica are all males but in the following year they become hermaphrodite and produce both sperm and eggs. The breeding season is late spring and several individuals come together in a group.
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Planktonic diatoms in freshwater and marine environments typically exhibit a "boom and bust" (or "bloom and bust") lifestyle. When conditions in the upper mixed layer (nutrients and light) are favourable (as at the spring), their competitive edge and rapid growth rate enables them to dominate phytoplankton communities ("boom" or "bloom"). As such they are often classed as opportunistic r-strategists (i.e. those organisms whose ecology is defined by a high growth rate, r).
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These species represent samples from many different habitats that were located near and around the lake, as well as farther up the valley. Benthic diatoms are the dominant type of siliceous algae found in the beds. These are easy to fossilize due to their silica shells. During periods of volcanism, the influxes of silica from volcanic ash lead to blooms of algae, which lead to algal mats and the exceptional preservation of the fossils.
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"Microbial heterotrophic metabolic rates constrain the microbial carbon pump." The American Association for the Advancement of Science, 2011. In general, dissolved organic carbon (DOC) is introduced into the ocean environment from bacterial lysis, the leakage or exudation of fixed carbon from phytoplankton (e.g., mucilaginous exopolymer from diatoms), sudden cell senescence, sloppy feeding by zooplankton, the excretion of waste products by aquatic animals, or the breakdown or dissolution of organic particles from terrestrial plants and soils.
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Corumbataia britskii is a species of armored catfish endemic to Brazil where it is found in small tributaries of the Sucuriú River, upper Paraná River Basin in the state of Mato Grosso do Sul. This species was found in deforested areas in moderate to fast current streams. It associates with aquatic macrophytes or the submerged portion of marginal vegetation. In its gut contents were found filamentous blue-green algae, chlorophytes, diatoms and bark.
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It accumulates more rapidly than any other pelagic sediment type, with a rate that varies from 0.3–5 cm/1000 yr. Siliceous ooze is ooze that is composed of at least 30% of the siliceous microscopic "shells" of plankton, such as diatoms and radiolaria. Siliceous oozes often contain lesser proportions of either sponge spicules, silicoflagellates or both. This type of ooze accumulates on the ocean floor at depths below the carbonate compensation depth.
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Theodoxus fluviatilis feeds mainly on diatoms living on stones, scraping biofilms and also consuming detritus. It can also consume Cyanobacteria and green algae as a poor-quality food supply. Cyanobacteria contain toxins and indigestible mucopolysaccharides, and green algae have cellulose in their cell walls (Theodoxus species have no cellulase enzymes to digest cellulose). They also graze on zygotes and germlings of brown alga Fucus vesiculosus, when the alga is small up to 1 mm.
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This shows the change in abundance with the change in season. Numerically, organic fragments and sand are most abundantly found in the gut. This is followed by diatoms, copepods and cladocerans making up much of the remainder. From the differences in abundance and types of particles in gut contents from different populations, it appears that Minytrema is not selective for any particular group, but harvests those groups that are seasonally or regionally abundant.
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Kronichthys subteres is a species of armored catfish endemic to Brazil where it occurs in the Ribeira de Iguape River basin. This species grows to a length of TL. K. subteres inhabits streams with rocky and sandy bottom. This species forages both during the day and at night, grazin on microscopic algae, mostly diatoms and green algae growing on rocks and submersed vegetation. They occasionally take chironomid and simuliid larvae, as well as tiny crustaceans.
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It is a benthic feeder and has a relatively diverse diet ranging from detritus, diatoms, and a wide variety of small invertebrates including microcrustacea, rotifers and the larvae of many insects.Kilgen R.H.. 1972. Food habits and growth of fingerling blacktail redhorse, Moxostoma poecilurum(Jordan), in ponds. Proceedings of the Louisiana Academy of Sciences 35:12-20. A Louisiana State University study revealed a specific diet “primarily composed of chironomid (55%) and heptageniid larvae (17%)”.
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Single celled photosynthetic organisms such as diatoms and cyanobacteria are generally the most important primary producers in the open ocean. Many of these cells, especially cyanobacteria, are too small to be captured and consumed by small crustaceans and planktonic larvae. Instead, these cells are consumed by phagotrophic protists which are readily consumed by larger organisms. Viruses can infect and break open bacterial cells and (to a lesser extent), planktonic algae (a.k.a. phytoplankton).
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Freeth, S.J.; C.O. Ofoegbu; and K.M. Onuoha (1992). Natural Hazards in West and Central Africa, pp. 50—51. It feeds on tiny organisms such as rotifers, diatoms and sponge spicules, and organic debris. The specific name honours the entomologist Gerhard Steinbach (1923-2016) of the Humboldt University of Berlin who was a member of an expedition which was led by zoologist Martin Eisentraut on which the type of this cichlid was collected.
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Twice daily the tide brings sand, clay and silt into the Wadden Sea. Dunes, formed by the wind out of fine grains of sand from the exposed mudflats, characterise the coast. The Wadden Sea is the second most productive ecosystem after the tropical rainforest - only the latter surpasses the Wadden Sea in terms of its living biomass. The forms of life found in the Wadden Sea include diatoms, snails, worms, mussels and shrimp.
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Predatory pulmonate land slugs, such as the ghost slug, use elongated razor-sharp teeth on the radula to seize and devour earthworms. Predatory cephalopods, such as squid, use the radula for cutting prey. In most of the more ancient lineages of gastropods, the radula is used to graze by scraping diatoms and other microscopic algae off rock surfaces and other substrates. Limpets scrape algae from rocks using radula equipped with exceptionally hard rasping teeth.
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Owing to the diverse functions of the remainder of the enzymes, molybdenum is a required element for life in higher organisms (eukaryotes), though not in all bacteria. Technetium, ruthenium, rhodium, palladium, silver, tin, and antimony have no biological role. Although cadmium has no known biological role in higher organisms, a cadmium-dependent carbonic anhydrase has been found in marine diatoms. Indium has no biological role and can be toxic as well as Antimony.
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The role of phytoplankton is better understood due to their critical position as the most numerous primary producers on Earth. Phytoplankton are categorized into cyanobacteria (also called blue-green algae/bacteria), various types of algae (red, green, brown, and yellow-green), diatoms, dinoflagellates, euglenoids, coccolithophorids, cryptomonads, chrysophytes, chlorophytes, prasinophytes, and silicoflagellates. Zooplankton tend to be somewhat larger, and not all are microscopic. Many Protozoa are zooplankton, including dinoflagellates, zooflagellates, foraminiferans, and radiolarians.
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Anabaena variabilis is a phylogenic-cousin of the more well-known species Nostoc spirrilum. Both of these species along with many other cyanobacteria are known to form symbiotic relationships with plants. Other cyanobacteria are known to form symbiotic relationships with diatoms, though no such relationship has been observed with Anabaena variabilis. Anabaena variabilis is also a model organism for studying the beginnings of multicellular life due to its filamentous characterization and cellular-differentiation capabilities.
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Ruth Patrick's research in fossilized diatoms showed that the Great Dismal Swamp between Virginia and North Carolina was once a forest, which had been flooded by seawater. Similar research proved that the Great Salt Lake was not always a saline lake. During the Great Depression, she volunteered to work as a curator of microscopy for the Academy of Natural Sciences, where she worked for no pay for eight years. She was payrolled in 1945.
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Feeding habits of Limacina are characterized by actively feeding on planktonic organisms such as bacteria, small crustaceans, gastropod larvae, dinoflagellates and diatoms. These prey items become entangled in a mucosal web (up to 5 cm wide) excreted by the animal that is, in turn, eaten along with the prey items. This net also provides positive buoyancy. Ciliated posterior footlobes and lateral footlobes move food collected by the mucosal web into the mouth.
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The works of Ralfs were: British Phænogamous Plants and Ferns, 1839, and The British Desmidieæ, 1848. This volume is ‘unsurpassed for the beauty and accuracy of its coloured plates,’ and is very rare and costly. His first paper, on Desmids and Diatoms, was contributed, at the suggestion of the Rev. Miles Joseph Berkeley, to the Edinburgh Botanical Society, and for many years his articles appeared in its Transactions and in the Annals of Natural History.
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Cyclotella is a genus of diatoms often found in oligotrophic environments, both marine and fresh water. It is in the family Stephanodiscaceae and the order Thalassiosirales. The genus was first discovered in the mid 1800s and since then has become an umbrella genus for nearly 100 different species, the most well-studied and the best known being Cyclotella meneghiniana. Despite being among the most dominant genera in low-productivity environments, it is relatively understudied.
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These sand grains rupture diatoms and other algal cells during digestion. This is an important aid to digestion, as the cell walls of plants are difficult for the fish enzymes to break down. Additional nutrition may be obtained from both root hairs and bacteria associated with algal growth, and immature insects, which are consumed in the winter when algae supply is limited. Dipteran and caddis fly larvae make up most of their insect diet.
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Mineralized tissues: sea sponge, sea shells, conch, dentin, radiolarian, antler, bone Mineralized tissues are biological tissues that incorporate minerals into soft matrices. Typically these tissues form a protective shield or structural support. Bone, mollusc shells, deep sea sponge Euplectella species, radiolarians, diatoms, antler bone, tendon, cartilage, tooth enamel and dentin are some examples of mineralized tissues. These tissues have been finely tuned to enhance their mechanical capabilities over millions of years of evolution.
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However, the importance of competition is also demonstrated by the production of phycotoxins that negatively impact other phytoplankton species. Flagellates (especially dinoflagellates) are the principle producers of phycotoxins; however, there are known toxigenic diatoms, cyanobacteria, prymnesiophytes, and raphidophytes. Because many of these allelochemicals are large and energetically expensive to produce, they are synthesized in small quantities. However, phycotoxins are known to accumulate in other organisms and can reach high concentrations during algal blooms.
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The legs with claws (chelipeds) are usually cream/white with no spots. This species typically lives in mud flats and can be found in large numbers in the San Francisco Bay, and coastal areas of Oregon and Washington states in the United States. Its diet primarily consists of diatoms and green algae, but it will occasionally eat meat. Although closely related, the adult H. oregonensis is smaller () than the purple shore crab, H. nudus.
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Calcitic skeletal parts of belemnites (Jurassic of Wyoming) Biomineralization, or biomineralisation is the process by which living organisms produce minerals, often to harden or stiffen existing tissues. Such tissues are called mineralized tissues. It is an extremely widespread phenomenon; all six taxonomic kingdoms contain members that are able to form minerals, and over 60 different minerals have been identified in organisms. Examples include silicates in algae and diatoms, carbonates in invertebrates, and calcium phosphates and carbonates in vertebrates.
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The iota class is the most recent class of CAs described. It has been discovered in the marine diatom Thalassiosira pseudonana, and is widespread among marine phytoplankton. In diatoms, the ι-CA is essential for the CO2-concentrating mechanisms and - in contrast to other CA classes - it can use manganese instead of zinc as metal cofactor. Homologs of the ι-CA have been also confirmed in gram-negative bacteria, where can be present as a protein homodimer.
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Since they are fed primarily by aquifers, the flow rate, mineral content and temperature range of chalk streams exhibit less seasonal variation than other rivers. They are mildly alkaline and contain high levels of nitrate, phosphate, potassium and silicate. In addition to algae and diatoms, the streams provide a suitable habitat for macrophytes (including water crowfoot) and oxygen levels are generally supportive of coarse fish populations. Of the 210 rivers classified as chalk streams globally, 160 are in England.
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Snowy owl Snow bunting Both flora and fauna are scarce owing to the harsh climate. Vegetation of the sea is mostly represented by diatoms, with more than 100 species. In comparison, the number of green algae, blue-green algae and flagellate species is about 10 each. The phytoplankton is characteristic of brackish waters and has a total concentration of about 0.2 mg/L. There are about 30 species of zooplankton with the concentration reaching 0.467 mg/L.
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In the Northwestern Mediterranean, the most abundant phytoplankton present are coccolithophorids, flagellates, and dinoflagellates. The Southeastern Mediterranean has a similar composition, where coccolithophorids and monads (nano- and picoplankton) make up the majority of the phytoplankton community in the DCM. In the Indian Ocean, the most abundant microorganisms present in the DCM are cyanobacteria such as prochlorophytes, coccolithophorids, dinoflagellates and diatoms. In the North Sea, dinoflagellates are the main phytoplankton species present in the DCM at and below the pycnocline.
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Frontonia is a genus of free-living unicellular ciliate protists, belonging to the order Peniculida. As Peniculids, the Frontonia are closely related to members of the genus Paramecium. However, whereas Paramecia are mainly bacterivores, Frontonia are capable of ingesting large prey such as diatoms, filamentous algae, testate amoebas,Dias, Roberto and D'Agosto, Marta. 2006. "Feeding Behavior of Frontonia leucas (Ehrenberg)." Revista Brasiliera de Zoologia 23 (3): 758-763 and even, in some circumstances, members of their own species.
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Melatonin confers cadmium tolerance by modulating critical heavy metal chelators and transporters in radish plants. Journal of Pineal Research: Molecular, Biological, Physiological and Clinical Aspects of Melatonin. 2020;69(1):doi:10.1111/jpi.12659. Administration of cadmium to cells causing the oxidative stress and increase the levels of antioxidants to protect the cells against macro molecular damage. The diatoms live in environments with very low zinc concentrations and cadmium performs the function normally carried out by zinc in other anhydrases.
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S. aeruginosa is a herbivorous deposit feeder. It consumes mainly epiphytic algae, but its diet also includes detritus, bacteria, aquatic plants, sand grains, diatoms, green algae, and cyanobacteria such as Microcystis. Its consumption of cyanobacteria during algal blooms may result in bioaccumulation of toxic microcystins (microcystin-LR, microcystin- RR) from Microcystis in the gonads, the hepatopancreas and the digestive tract. Adult snails feeding ad libitum under ideal laboratory conditions eat 16.0 mg of fish food daily.
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Salt marshes are sometimes included in lagoons, and the difference is not very marked; the Venetian Lagoon in Italy, for example, is made up of these sorts of animals and or living organisms belonging to this ecosystem. They have a big impact on the biodiversity of the area. Salt marsh ecology involves complex food webs which include primary producers (vascular plants, macroalgae, diatoms, epiphytes, and phytoplankton), primary consumers (zooplankton, macrozoa, molluscs, insects), and secondary consumers.Vernberg, F. J. 1993.
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Selenium is incorporated into several prokaryotic selenoprotein families in bacteria, archaea, and eukaryotes as selenocysteine, where selenoprotein peroxiredoxins protect bacterial and eukaryotic cells against oxidative damage. Selenoprotein families of GSH-Px and the deiodinases of eukaryotic cells seem to have a bacterial phylogenetic origin. The selenocysteine-containing form occurs in species as diverse as green algae, diatoms, sea urchin, fish and chicken. Selenium enzymes are involved in utilization of the small reducing molecules glutathione and thioredoxin.
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In 1909, he was made head of the department of physiology at the Carlsberg Laboratory, a post he held until his early death. Schmidt worked in parallel on phycology, where he described the genus Richelia (filamentous heterocyst- forming Cyanobacteria dwelling inside diatoms), on plant physiology and genetics, especially of hops, and on large-scale oceanography and ichthyology. Beginning in 1904, Johannes Schmidt led a series of expeditions into the Mediterranean Sea and the North Atlantic to investigate eels.
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Their underslung mouths make them especially well adapted for feeding on benthic organisms, including crustaceans, insect larvae and mollusks, which they root out from the gravel and stones of the riverbed. Barbel diets change as the fish develop from fry to juveniles and then to adults. Diatoms that cover rocks and the larvae of non-biting midges (Chironomidae) are particularly important foods for young fish. Males become mature after three to four years, females after five to eight years.
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Thus, having higher NCR ratios is indicative of a younger age. It appears that 24-norcholestane is not present until the emergence of diatoms. A 2008 study found that 24-norcholestanes also correlated with dinoflagellates in lacustrine sediments in China. In a 2012 study, 24-norcholestanes were found in oils and Cambrian–Ordovician source rocks from the Tarim Basin in China at much higher levels than in the 1998 study (NCRs were equivalent to Cretaceous source rocks).
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The specialized, sympagic (i.e. ice-associated) community within the sea ice is found in the tiny (mostly <1mm diameter) liquid filled network of pores and brine channels or at the ice-water interface. The organisms living within the sea ice are consequently small (<1mm), and dominated by bacteria, and unicellular plants and animals. Diatoms, a certain type of algae, are considered the most important primary producers inside the ice with more than 200 species occurring in Arctic sea ice.
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For instance, diatom growth rate becomes limited when the supply of silicate is depleted.Kristiansen, S., Farbrot, T., and Naustvoll, L. (2001). "Spring bloom nutrient dynamics in the Oslofjord". Marine Ecology Progress Series 219: 41–49 Since silicate is not required by other phytoplankton, such as dinoflagellates, their growth rates continue to increase. For example, in oceanic environments, diatoms (cells diameter greater than 10 to 70 µm or larger) typically dominate first because they are capable of growing faster.
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In 1939, Volcani became a member of the Sieff Institute in Rehovot, later renamed the Weizmann Institute of Science. He headed its laboratory of microbiology until 1959, when he joined the faculty at Scripps Institution of Oceanography. He decided to focus on diatoms, one of the very few organisms that use silicon rather than calcium for their skeletal structures. Silicon is one of the most abundant elements on earth, and in 1959 no one was working on its metabolism.
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The diet of T. gigas is chiefly composed of molluscs, detritus, and polychaetes, which it seeks on the ocean floor. House crows have been observed to turn T. gigas over and eat the soft underside, while gulls only attack individuals that are already stranded upside-down. Since horseshoe crabs do not moult after they have reached sexual maturity, they are often colonised by epibionts. The dominant diatoms are species of the genera Navicula, Nitzschia, and Skeletonema.
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Larkum and his colleagues have intensively investigated Prochloron, in areas of gene sequencing and molecular phylogeny. In the 1990s, he and team of scientists cloned the genes of Prochloron to understand the affinities of this alga to chloroplasts of green algae and higher plants. He conducted considerable research in the evolution of Prochloron and cyanobacteria and was also involved in phylogenetic studies of cab genes in a variety of eukaryotic algae, Pavlova lutheri, diatoms and Amphidinium.
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Chlorophyll c is a form of chlorophyll found in certain marine algae, including the photosynthetic Chromista (e.g. diatoms and brown algae) and dinoflagellates. It has a blue-green color and is an accessory pigment, particularly significant in its absorption of light in the 447-52 nm wavelength region. Like chlorophyll a and chlorophyll b, it helps the organism gather light and passes a quanta of excitation energy through the light harvesting antennae to the photosynthetic reaction centre.
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Symbiodinium are colloquially called zooxanthellae, and animals symbiotic with algae in this genus are said to be "zooxanthellate". The term was loosely used to refer to any golden-brown endosymbionts, including diatoms and other dinoflagellates. Continued use of the term in the scientific literature is discouraged because of the confusion caused by overly generalizing taxonomically diverse symbiotic relationships. In 2018, the systematics of Symbiodiniaceae was revised, and the distinct clades have been reassigned into seven genera.
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When this water evaporates in the desert heat, the minerals remain behind as part of the crust. Both the slopes and the floor of the caldera contain thick layers of fossilized aquatic gastropods and diatoms, indicating that the caldera was once home to a deep lake. During the Last Glacial Maximum, the lake may have been up to deep. Radiocarbon dating on some of these samples indicates an age of approximately 14,500–15,000 years Before Present.
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Foulden Maar was a deep crater lake 23 million years ago, then gradually filled in over about 100,000 years, preserving fossil plants and animals in its cool anoxic depths between layers of diatoms. At some point the lake probably breached its rim, perhaps during a flood, creating a waterway through which fishes could enter and form a landlocked non-migratory population. The exceptionally-well-preserved fossils of G. effusus were recovered by manually splitting layers of soft diatomite.
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On 29 December 2012 a green fireball was observed in Polonnaruwa Province, Sri Lanka. It disintegrated into fragments that fell to the Earth near the villages of Aralaganwila and Dimbulagala and in a rice field near Dalukkane. Rock samples were submitted to the Medical Research Institute of the Ministry of Health in Colombo. The rocks were sent to the University of Cardiff in Wales for analysis, where Chandra Wickramasinghe's team analyzed them and claimed that they contained extraterrestrial diatoms.
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Ryan, John. "Red Tide & HAB Studies in Monterey Bay", Monterey Bay Sanctuary Advisory Council Meeting, August 15, 2008 They are visible in water at a concentration of 1,000 algae cells per milliliter, while in dense blooms they can measure over 200,000 per milliliter."Intense, widespread algal blooms reported in Chesapeake Bay", Science Daily, Sept. 1, 2015 Diatoms produce domoic acid, another neurotoxin, which can cause seizures in higher vertebrates and birds as it concentrates up the food chain.
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Type B killer whales, also known as Park Ice Orcas, are gray, black, and white colored with a dorsal cape and a very large eye patch. They are located in loose-packed ice waters and prey upon pinnipeds. They may seem to appear brown or yellowish due to the presence of diatoms in the water and have a cape of pale color. Park Ice Orcas prey mainly on seals by using a famous technique called wave-washing.
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Pyrenoids are found in algal lineages, irrespective of whether the chloroplast was inherited from a single endosymbiotic event (e.g. green and red algae, but not in glaucophytes) or multiple endosymbiotic events (diatoms, dinoflagellates, coccolithophores, cryptophytes, chlorarachniophytes, and euglenozoa. Some algal groups, however, lack pyrenoids altogether: "higher" red algae and extremophile red algae, the green alga genus Chloromonas, and "golden algae". Pyrenoids are usually considered to be poor taxonomic markers and may have evolved independently many times.
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Pleuroncodes planipes usually feeds on protists and zooplankton, but will feed by filtering blooms of diatoms. As the most abundant species of micronekton in the California Current, Pleuroncodes planipes fills an important ecological niche converting primary production into energy that larger organisms can use. P. planipes is accordingly an important food item for many species of birds, marine mammals and fish. It is favoured by tuna, leading to one of the species' common names – "tuna crab".
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The Belgian Co-ordinated Collections of Micro-organisms (BCCM) is a Belgian government funded consortium of seven scientific institutions, who manage and exploit a collection of microbial and genetic resources. The consortium comprises more than 269,000 publicly available strains of bacteria including mycobacteria and cyanobacteria, filamentous fungi, yeasts, diatoms and plasmids. BCCM is embedded in international initiatives such as the World Federation of Culture Collections (WFCC) and operates in compliance with the rules of the Nagoya Protocol.
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Pelagic Clays containing iron- manganese micronodules, quartz, plagioclase, orthoclase, magnetite, volcanic glass, montmorillonite, illite, smec- tite, foraminiferal remains, diatoms, and sponge spicules made up the uppermost stratigraphic section at each site it was found at. This sediment type consisted of 4.2 percent of the total thickness of sediment recovered by the Deep Sea Drilling Project (DSDP). Biogenic pelagic silica sediments consist of radiolarian, diatomaceous, silicoflagellate oozes, and chert. It makes up 4.3% of the sediment thickness recovered.
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Richard Brice HooverInvitation to submit a paper to International Journal of Astronomy and Astrophysics (Prof. Hoover) (born January 3, 1943) is a scientist who has authored 33 volumes and 250 papers on astrobiology, extremophiles, diatoms, solar physics, X-ray/EUV optics and meteorites. He holds 11 U.S. patents and was 1992 NASA Inventor of the Year. He was employed at the United States' NASA Marshall Space Flight Center from 1966 to 2012, where he worked on astrophysics and astrobiology.
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The molecule laminarin (also known as laminaran) is a storage glucan (a polysaccharide of glucose) found in brown algae. It is used as a carbohydrate food reserve in the same way that chrysolaminarin is used by phytoplankton, especially in diatoms. It is created by photosynthesis and is made up of β(1→3)-glucan with β(1→6)-branches. It is a linear polysaccharide, with a β(1→3):β(1→6) ratio of 3:1.
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The small (about 500 μm) bivalve Transenella tantilla has also been found living in the stomach. The relationship with both nematodes and T. tantilla is uncertain. The exhalant siphon is kept below the sediment surface (about 1 cm). The gut clearance time for inert particles of M. nasuta ranges from 1 to 9 hours with smaller particles and diatoms believed to remain longer than other particles ingested due to their disproportionably high presence in the stomach during dissections.
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The microbial loop functions differently in sea ice, as compared to oligotrophic or temperate waters. Animals found in the extreme polar environments depend on the high bacterial production as a food source, despite the slow turnover of DOM. The microbial production of ammonium in nitrate-rich Antarctic waters may provide the necessary reductants for nitrogen fixation, increasing primary productivity of light-limited phytoplankton. Phytoflagellates and diatoms found in the Antarctic pelagic environment are directly digestible by metozoan herbivores.
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Naqvi organized the largest OIF experiment conducted so far – called the LOHAFEX - in the Southern Ocean, which yielded quite different results from those of previous studies. In the absence of diatoms, due to silicon deficiency in the study area, intense grazing of smaller phytoplankton by zooplankton prevented large build-up of phytoplankton biomass and carbon export to the deep sea. The LOHAFEX findings imply a much lower than expected potential of OIF for sequestration of atmospheric CO2.
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Diatoms are also found in El Tatio waters, including Synedra species, which are often found attached to filamentous substrates, and algae are found in the waters. Among bacteria identified in the somewhat colder flowing waters are bacteroidetes and proteobacteria, with Thermus species in the hot waters. Various archaeans have been cultured from El Tatio waters, with hot springs producing crenarchaea, desulfurococcales and methanobacteriales. One species, Methanogenium tatii, has been discovered at El Tatio, and is a methanogen recovered from a warm pool.
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Marine diatoms have been found to express a new form of ζ carbonic anhydrase. T. weissflogii, a species of phytoplankton common to many marine ecosystems, was found to contain carbonic anhydrase with a cadmium ion in place of zinc. Previously, it had been believed that cadmium was a toxic metal with no biological function whatsoever. However, this species of phytoplankton appears to have adapted to the low levels of zinc in the ocean by using cadmium when there is not enough zinc.
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Sediments left by the lake indicate the presence of gastropods, ostracods and stromatolites. At Estancia Vinto, several different species have been found, including the ostracods Amphicypris, Candonopsis, Darwinula, Limnocythere, Limnocythere bradburyi, Limnocythere titicaca and the molluscs Anysancylus crequii, Ecpomastrum mirum, Littoridina poopoensis, Taphius montanus. Some species variation may indicate that water levels at the site fluctuated; for example the deepwater diatoms Cyclotella meneghiniana and Cyclotella stelligera but also benthic species. Around the lake, Polylepis expanded and quantities of water supported Isoetes and Myriophyllum.
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The arrangement of teeth (denticles) on the radular ribbon varies considerably from one group to another. In most of the more ancient lineages of gastropods, the radula is used to graze, by scraping diatoms and other microscopic algae off rock surfaces and other substrates. Predatory marine snails such as the Naticidae use the radula plus an acidic secretion to bore through the shell of other molluscs. Other predatory marine snails, such as the Conidae, use a specialized radular tooth as a poisoned harpoon.
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Marine diatoms; an example of planktonic microalgae In a reversal of the pattern on land, in the oceans, almost all photosynthesis is performed by algae, with a small fraction contributed by vascular plants and other groups. Algae encompass a diverse range of organisms, ranging from single floating cells to attached seaweeds. They include photoautotrophs from a variety of groups. Eubacteria are important photosynthetizers in both oceanic and terrestrial ecosystems, and while some archaea are phototrophic, none are known to utilise oxygen-evolving photosynthesis.
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At the adjournment the coroner released Ambrose Ball's body to his family who had commissioned an independent autopsy. After the adjournment, Ball's mother Ruth Lovell said, "His body was dumped in that river, I am sure of that". At an inquest hearing in January 2016, an expert witness testified that the presence of diatoms made it most likely that Ball had drowned. Another witness testified that he had seen a man walking around dazed and "being ushered into another car" by two men.
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The pH-sensitivity of diatom communities had been recognised since at least the 1930s, when Friedrich Hustedt developed a classification for diatoms, based on their apparent pH preferences. Gunnar Nygaard subsequently developed a series of diatom pH indices. By calibrating these indices to pH, Jouko Meriläinen introduced the first diatom-pH transfer function. Using diatom and chrysophyte fossil records, research groups were able to clearly demonstrate that many northern lakes had rapidly acidified, in parallel with increased industry and emissions.
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Other eukaryotic taxa have experienced one or more polyploidization events during their evolutionary history (see Albertin and Marullo, 2012 for review). The oomycetes, which are non-true fungi members, contain several examples of paleopolyploid and polyploid species, such as within the genus Phytophthora. Some species of brown algae (Fucales, Laminariales and diatoms) contain apparent polyploid genomes. In the Alveolata group, the remarkable species Paramecium tetraurelia underwent three successive rounds of whole-genome duplication and established itself as a major model for paleopolyploid studies.
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British Museum Micromosaic brooch with the Lamb of God, made by the firm of Castellani, c. 1860 It was even imitated by porcelain painters, who painted faint lines across their work to suggest the edges of tesserae.MMA See 4th para of "Themes" Butterfly scales and diatoms were also used to create tesserae, Henry Dalton (1829–1911) of Bury St Edmunds being a well known practitioner. A distinctive feature of micromosaics is that the tesserae are usually oblong rather than square.
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If the amount is greater than the benthic detritivores can process, the phytodetritus forms a fluffy layer on the surface of the sediment. It accumulates in many shallow and deep water locations throughout the world. Phytodetritus varies in colour and appearance and may be greenish, brown or grey, flocculent or gelatinous. It includes the microscopic remains of diatoms, dinoflagellates, dictyochales, coccolithophores, foraminiferans, phaeodareans, tintinnids, crustacean eggs and moults, protozoan faecal pellets, picoplankton and other planktonic matter embedded in a membranous gelatinous matrix.
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The darter characine is an open water fish, and was one of several fish species in a reservoir on the Paraná River to thrive when large submerged macrophytes were removed. The diet consists of diatoms, green algae and the periderm of aquatic vegetation, perhaps removed accidentally while the fish scrapes off the algae. The karyotype of this fish varies between populations. In the Upper Paraná basin, the sexes have distinct diploid numbers, the males showing 2n = 54 and the females 2n = 55.
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Examination of the contents of the gut shows that Hediste diversicolor is a predator and generalist scavenger, able to adapt its diet to whatever is currently available. It spins a mucus net at the entrance of its burrow in which it traps phytoplankton, zooplankton, diatoms, bacteria and other small particles. It creates a water current through its tube by writhing about inside to draw particles through the net. Periodically it rolls the net up and swallows it before spinning another.
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The Japanese sea cucumber sifts through the sediment on the seabed with its tentacles and feeds on detritus and other organic matter including plant and animal remains, bacteria, protozoa, diatoms and faeces. The sexes are separate in the Japanese sea cucumber. Males and females release a mass of gametes into the sea where fertilization takes place. In the laboratory, spawning from ripe gonads can be induced by varying the temperature at which the adults are kept or by use of the neuropeptide cubifrin.
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Because a diverse community of invertebrates and algae use its shell as a base, the Antarctic scallop is considered to be a "foundation species"; a species of great importance in its habitat. The fact that the scallops can swim and move to other locations aids in the dispersal of these organisms. The epiphytes include benthic diatoms, forams, bacteria, bryozoans, sponges and algae. The foram Cibicides refulgens lives parasitically on the scallop's shell and also grazes on the algae and bacteria growing there.
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Subfossils are also often found in depositionary environments, such as lake sediments, oceanic sediments, and soils. Once deposited, physical and chemical weathering may alter the state of preservation, and small subfossils can also be ingested by living organisms. Subfossil remains that date from the Mesozoic are exceptionally rare, are usually in an advanced state of decay, and are consequently much disputed. The vast bulk of subfossil material comes from Quaternary sediments, including many subfossilized chironomid head capsules, ostracod carapaces, diatoms, and foraminifera.
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Fossil diatoms are preserved in diatomite (also known as diatomaceous earth), which is one of the by-products of the transformation from ooze to rock formation. As diatomaceous particles began to sink to the ocean floor, carbon and silica were sequestered along continental margins. The carbon sequestered along continental margins has become the major petroleum reserves of today. Diatom evolution marks a time in Earth's geologic history of significant removal of carbon dioxide from the atmosphere while simultaneously increasing atmospheric oxygen levels.
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P. erythrodactyla relies mangrove leaf detritus for about 65%-80% of its nutrition, and on benthic microalgae such as diatoms for between 20% and 35% of its nutrition. Sesarmid crabs are generally considered to be a monophyletic taxon (that is, all genetically deriving from a common ancestor) of Grapsoidea, but recent reclassifications of the genera Sesarma and Parasesarma (both considered polyphyletic) have resulted in a reshuffling of the species. A type specimen exists in the Melbourne Museum Discovery Centre (object drawer 15).
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The majority of planktonic foraminifera are found in the globigerinina, a lineage within the rotaliida. However, at least one other extant rotaliid lineage, Neogallitellia, seems to have independently evolved a planktonic lifestyle. Further, it has been suggested that some Jurassic fossil foraminifera may have also independently evolved a planktonic lifestyle, and may be members of Robertinida. A number of forams have unicellular algae as endosymbionts, from diverse lineages such as the green algae, red algae, golden algae, diatoms, and dinoflagellates.
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The fish can be found in or next to riffle areas in warm water, medium sized creeks and small rivers. It can also occur in cold water streams, tiny creeks and large rivers and on occasion in reservoirs. Its diet mainly consists of insect larvae, crustaceans, mollusks, diatoms, and bits of vegetation. While feeding, it scrapes of the top surface of rubble, turns over stones on the bottom, and sucks the loosened material which contains a variety of small organisms.
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Suckers use their cartilaginous jaws to scrape the algae and detritus off the stones at the bottom, and despite any shortages of these foods, suckers show little seasonal movement. Diatoms, detritus, algae, and other organic debris have been found in the gut. They are unique in that they are the only members of the genus to hybridize with other members of the same genus, increasing gene flow among species. They can also live to be more than 20 years old.
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It is an accessory pigment found in the chloroplasts of many brown macroalgae, such as Fucus spp., and the golden-brown unicellular microalgae, the diatoms. It absorbs blue and green light at bandwidth 450-540 nm, imparting a brownish-olive color to algae. Fucoxanthin has a highly unique structure that contains both an epoxide bond and hydroxyl groups along with an allenic bond (carbon-carbon double bond) and a conjugated carbonyl group (carbon-oxygen double bond) in the polyene chain.
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Leiognathus brevirostris, commonly known as the shortnose ponyfish, is a fish of brackish and marine waters found from Indo-West Pacific to the Indian coasts and off Sri Lanka to China and south of Australia. Like its relatives, the fish is an amphidromous, demersal species which feeds on diatoms, copepods, Lucifer, nematodes and polychaetes. The fish has eight dorsal spines, sixteen dorsal soft rays, three anal spines and fourteen anal soft rays. Fresh specimens possess a golden gleam which fades with dryness.
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Prior to draining, it had provided habitat for algae called diatoms, which formed a layer of diatomite on the bottom of the tarn when they died. From the 1930s until 1971, diatomite was extracted from the former bed, resulting in the tarn returning, although somewhat smaller than it had once been. Below the tarn, the river is joined by Park Beck, flowing from the west. Ullthwaite Bridge carries a minor track over the river, while Scroggs Bridge carries the road to Kentmere.
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Vegetative cells of diatoms are diploid (2N) and so meiosis can take place, producing male and female gametes which then fuse to form the zygote. The zygote sheds its silica theca and grows into a large sphere covered by an organic membrane, the auxospore. A new diatom cell of maximum size, the initial cell, forms within the auxospore thus beginning a new generation. Resting spores may also be formed as a response to unfavourable environmental conditions with germination occurring when conditions improve.
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After mating the females carry the eggs downstream from freshwater to the estuarine areas to spawn as the larvae must develop in saline water. As the eggs are unable to hatch at higher salinities the females migrate downstream in the rainy season when salinity in the estuarine areas has been lowered. The larvae then move back upstream into freshwater to complete their development. M. vollenhoveni is omnivorous and the major part of its diet consists of plant materials, algae, diatoms, protozoa and invertebrates.
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Scientists boil the sample and then add 50 ml of nitric acid solution. The color of the mixture will turn from yellow to transparent. After 48 hours when the sample has reached room temperature it is centrifuged, which allows the organic matter to completely oxidize, and the pellet is extracted, mixed with distilled water, and examined on a slide. The ratios of the different specimen of diatoms are counted, which allows scientists to match the area where the victim entered the water.
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They feed by sucking in small organisms of adequate size. The composition of the food items differs between species, as the size of the sucked in food components depends on each species’ body size. While the biggest species Ch. diaphanus consumes organisms in the size class of about 0.3–3 mm, which mostly contains zooplankton (rotifers, water fleas etc.), Ch. limnaei e.g. selects organisms in the order of 0.03-0.3 mm, which are mainly algae (diatoms and green algae) or very small zooplankton.
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Amathia vidovici feeds on bacteria, diatoms and phytoplankton by sifting particles from the surrounding water with its lophophore. Amathia vidovici is a hermaphrodite and different zooids on the same colony may be male or female, depending on their stage of development. The embryology of Amathia vidovici has not been studied but most bryozoans produce large, yolky eggs which are retained in the body cavity. Sperm is shed into the water and some self-fertilisation probably takes place within the colony.
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Polyunsaturated aldehydes are oxylipins that are formed from lipids (specifically the fatty acid portion of lipids) when diatoms are exposed to environmental stresses. Stresses can include nutrient limitations, grazing by predators, and wounding.Schilmiller, Anthony L., and Gregg A. Howe. "Systemic Signaling in the Wound Response." Current Opinion in Plant Biology 8.4 (2005): 369-77. Web. In particular, damage to diatom cells as a result of grazing by zooplankton invokes a chemical defense mechanism that produces PUA’s as secondary metabolites from fatty acids.
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The outer surface of the epidermis is normally formed of epithelial cells and secretes an extracellular matrix which provides support to the organism. An endoskeleton derived from the mesoderm is present in echinoderms, sponges and some cephalopods. Exoskeletons are derived from the epidermis and is composed of chitin in arthropods (insects, spiders, ticks, shrimps, crabs, lobsters). Calcium carbonate constitutes the shells of molluscs, brachiopods and some tube-building polychaete worms and silica forms the exoskeleton of the microscopic diatoms and radiolaria.
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The Leon Springs pupfish (Cyprinodon bovinus) is a species of fish in the family Cyprinodontidae. It is endemic to Pecos County, Texas in the United States. It is a federally listed endangered species. The Leon Springs pupfish is found at the shallow edges of spring-fed wetland pools, where it is most frequently observed in areas without vegetation.. Its diet consists of diatoms, amphipods, and ostracods. This fish was first discovered in 1851 at Leon Springs, near Fort Stockton, Texas.
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Stream dwellers mostly have larger mouths, shallow bodies and caudal fins; they attach themselves to plants and stones and feed on the surface films of algae and bacteria. They also feed on diatoms, filtered from the water through the gills, and stir up the sediment at bottom of the pond, ingesting edible fragments. They have a relatively long, spiral-shaped gut to enable them to digest this diet. Some species are carnivorous at the tadpole stage, eating insects, smaller tadpoles and fish.
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Algae constitute a polyphyletic group since they do not include a common ancestor, and although their plastids seem to have a single origin, from cyanobacteria, they were acquired in different ways. Green algae are examples of algae that have primary chloroplasts derived from endosymbiotic cyanobacteria. Diatoms and brown algae are examples of algae with secondary chloroplasts derived from an endosymbiotic red alga. Algae exhibit a wide range of reproductive strategies, from simple asexual cell division to complex forms of sexual reproduction.
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H. anomala is an opportunistic omnivore that feeds primarily on zooplankton, particularly cladocerans, but also consumes detritus, phytoplankton (particularly green algae and diatoms), and insect larvae, and is occasionally cannibalistic. Younger individuals feed mainly on phytoplankton. The proportion of zooplankton consumed in the mysid's diet increases with its body size. A bloody-red mysid feeds using its thoracic limbs, either by capturing prey with its endopods or by removing food particles from its body that are filtered from incoming currents by its exopods.
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It is much more important to the metabolism of plants, particularly many grasses, and silicic acid (a type of silica) forms the basis of the striking array of protective shells of the microscopic diatoms. Phosphorus is essential for life. As phosphate, it is a component of DNA, RNA, ATP, and also the phospholipids that form all cell membranes. Demonstrating the link between phosphorus and life, elemental phosphorus was historically first isolated from human urine, and bone ash was an important early phosphate source.
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Some marine alt=Photo of mostly transparent diatoms of varying shapes: one resembles a bagel, another a short length of tape, others look like tiny kayaksThe name plankton is derived from the Greek adjective πλαγκτός (), meaning errant, and by extension, wanderer or drifter, and was coined by Victor Hensen in 1887.Hensen, V. 1887. Uber die Bestimmung des Planktons oder des im Meere treibenden Materials an Pflanzen und Thieren. V. Bericht der Commission zur Wissenschaftlichen Untersuchung der Deutschen Meere, Jahrgang 12-16, p.
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Like other mollusks, the Appalachian Elktoe feeds itself by picking out particles of food that are in the water. The specifics of their diet has yet to be determined, but it has been assumed that the Appalachian Elktoe survives off the same things as other freshwater mussels: detritus, diatoms, phytoplankton, and zooplankton (Churchill and Lewis, 1921). The reproductive cycle of the Appalachian Elktoe is also similar to other native freshwater mussels. First, the male releases a trail of sperm into the water column.
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The spines are essentially moveable extensions of the body wall, and are hollow and covered by cuticle. The head is completely retractable, and is covered by a set of neck plates called placids when retracted.Echinoderes spinifurca Kinorhynchs eat either diatoms or organic material found in the mud, depending on species. The mouth is located in a conical structure at the apex of the head, and opens into a pharynx and then an oesophagus, both of which are lined by cuticle.
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The diatom lineage may go back 180 to 250 million years ago (Mya). About 65 Mya, diatoms survived a mass extinction in which roughly 85% of all species perished. Until 1994, the genus was known as Nitzschia, but was changed to Pseudo-nitzschia because of the ability to form chains of overlapping cells, as well as other minor morphological differences. While the genus can be readily recognized using light microscopy, identification of distinct species can require taxonomic expertise and be extremely time- consuming.
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The worldwide association of diatomite deposits and volcanic deposits suggests that the availability of silica from volcanic ash may be necessary for thick diatomite deposits. Diatomaceous earth is sometimes found on desert surfaces. Research has shown that the erosion of diatomaceous earth in such areas (such as the Bodélé Depression in the Sahara) is one of the most important sources of climate-affecting dust in the atmosphere. The siliceous frustules of diatoms accumulate in fresh and brackish wetlands and lakes.
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The species and taxa stored in Neotoma represent a breadth of terrestrial and aquatic organisms: plants (pollen and larger fossils), mammals and other vertebrates, insects and other invertebrates, diatoms, ostracodes, and testate amoebae. Neotoma also stores the age estimates provided by radiometric dating (e.g. radiocarbon, lead-210) and the age estimates that are derived from statistical models of age as a function of depth in sediment column. The Neotoma data model is extensible to other types of paleoecological and paleoenvironmental variables.
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Semibalanus balanoides During tidal immersion, the food supply to intertidal organisms is subsidized by materials carried in seawater, including photosynthesizing phytoplankton and consumer zooplankton. These plankton are eaten by numerous forms of filter feeders—mussels, clams, barnacles, sea squirts, and polychaete worms—which filter seawater in their search for planktonic food sources. The adjacent ocean is also a primary source of nutrients for autotrophs, photosynthesizing producers ranging in size from microscopic algae (e.g. benthic diatoms) to huge kelps and other seaweeds.
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When diatoms die and their organic material decomposes, the frustules sink to the bottom of the aquatic environment. This remnant material is diatomite or "diatomaceous earth", and is used commercially as filters, mineral fillers, mechanical insecticide, in insulation material, anti-caking agents, as a fine abrasive, and other uses.Diatom Frustule 2 There is also research underway regarding the use of diatom frustules and their properties for the field of optics, along with other cells, such as those in butterfly scales.
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The cui-ui (Chasmistes cujus) is a large sucker fish endemic to Pyramid Lake and, prior to its desiccation in the 20th century, Winnemucca Lake in northwestern Nevada. It feeds primarily on zooplankton and possibly on nanoplankton (such as algae and diatoms). The maximum size of male cui-ui is approximately and , while females reach approximately and . The life span of cui-ui is typically about forty years, but the fish do not reach sexual maturity until at least age eight.
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The other species was named C. cassandrae, characterized by its elliptically shaped valve paired with its coarse striae. Most notably it has a scattered ring of central fultoportulae (21). Discovering fossils is not often a credible enough way to determine a new species within the phylum of diatoms, given that determining underlying mechanisms based on morphological variability is unreliable. It's best to use both morphological and paleoecological data obtained from samples- the two are often difficult to obtain just from fossils (20).
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It is known to eat detritus, bacteria, phytoplankton, diatoms, and algae. The shiner is threatened by numerous predators, such as crappie, bass, and the introduced Flathead Catfish. However, the adult Flathead Catfish does not pose a significant threat because of the differences in habitats of the two species within the river; the juvenile catfish, which share the same habitat as the shiner, may pose a larger threat. This shiner spawns around May 15 when the water temperature reaches 19 °C (66.2 °F).
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Rhynchopus is a genus of flagellate excavates in the class Diplonemea. They usually have flagella of different lengths and a single subapical opening with the flagellar pocket openings and adjacent feeding apparatus merging into one. When food is scarce, mobile flagellated cells are produced, suggesting the presence of a fully flagellated and dispersive phase in the life cycle, serving to distinguish Rhynchopus from Diplonema. Most species are free- living, others are symbionts and R. coscinodiscivorus is an intracellular parasite of diatoms.
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The tail fin and tip is fragile and will easily tear, which is seen as an adaptation to escape from predators which tries to grasp them by the tail. Tadpoles are typically herbivorous, feeding mostly on algae, including diatoms filtered from the water through the gills. Some species are carnivorous at the tadpole stage, eating insects, smaller tadpoles, and fish. The Cuban tree frog (Osteopilus septentrionalis) is one of a number of species in which the tadpoles can be cannibalistic.
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Although lakes also showed a tendency to acidify slightly during their early (late-glacial) history, the pH of most lakes had remained stable for several thousand years prior to their recent, anthropogenic acidification. In recent years palaeolimnologists have recognised that climate is a dominant force in aquatic ecosystem processes, and have begun to use lacustrine records to reconstruct paleoclimates. Sensitive records of climate change have been developed from a variety of indicators including, for example, paleotemperature reconstructions derived from chironomid fossils, and palaeosalinity records inferred from diatoms.
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Like other salps, T. vagina feeds by consuming plankton nutrient water on one end of its body, filtering it via an internal net made of mucus, and spewing the water out the other end. Their internal net is very effective, catching particles spanning four magnitudes in size. This action also allows them to move through the water column, classifying them as nektonic. T. vagina feeds on marine plankton, including single-celled organisms such as dinoflagellates, silicoflagellates, diatoms, and tintinnids, as well as copepods and other small particles.
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Many protists and bacteria produce other cell surface structures apart from cell walls, external (extracellular matrix) or internal. Many algae have a sheath or envelope of mucilage outside the cell made of exopolysaccharides. Diatoms build a frustule from silica extracted from the surrounding water; radiolarians, foraminiferans, testate amoebae and silicoflagellates also produce a skeleton from minerals, called test in some groups. Many green algae, such as Halimeda and the Dasycladales, and some red algae, the Corallinales, encase their cells in a secreted skeleton of calcium carbonate.
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Bulletin Department of Geology, University of California 5:136 It is the official state fossil of Wyoming, and the most commonly excavated fossil fish in the world. Knightia belongs to the same taxonomic family as herring and sardines, and resembled the former closely enough that both Knightia alta and Knightia eocaena were originally described as species of true herring in the genus Clupea. As with modern-day clupeids, Knightia spp. likely fed on algae and diatoms, as well as insects and occasionally smaller fish.
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Various species of Trichodesmium have been described based on morphology and structure of colonies formed. Colonies may consist of aggregates of several to several hundred trichomes and form fusiform (called "Tufts") colonies when aligned in parallel, or spherical (called "Puffs") colonies when aligned radially. Trichodesmium colonies have been shown to have large degree of associations with other organisms, including bacteria, fungi, diatoms, copepods, tunicates, hydrozoans, and protozoans among other groups. These colonies may provide a source of shelter, buoyancy, and possibly food in the surface waters.
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A dominant organism in warm oligotrophic waters, five species within the genus Hemiaulus receive fixed nitrogen from R. intracellularis. Hemiaulus-Richella symbioses are up to 245 times more abundant than the former, with 80% to 100% of Hemilalus cells containing the cyanobiont. Nitrogen fixation in the Hemiaulus-Richella symbiosis is 21 to 45 times greater than in the Richella- Rhizosolenia symbiosis within the southwestern Atlantic and Central Pacific Gyre, respectively. Other genera of diatoms can form symbioses with cyanobacteria; however, their relationships are less known.
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Nutrients dynamics vary in the river basin from the headwaters to the main river and dams, to finally reaching the Columbia River estuary and ocean. Upstream in the headwaters, salmon runs are the main source of nutrients. Dams along the river impact nutrient cycling by increasing residence time of nutrients, and reducing the transport of silicate to the estuary, which directly impacts diatoms, a type of phytoplankton. The dams are also a barrier to salmon migration, and can increase the amount of methane locally produced.
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The net is usually built underneath a rock where a current of water flows through it. The downstream end of the net is free to move and has an opening to permit a respiratory current to flow through, and groups of nets are often built besides each other. The larva moves about inside the net and feeds on the fine organic matter and diatoms that get caught in the mesh structure. Much of its time is spent scraping this deposit off the net with specialised mouthparts.
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Fragilariopsis kerguelensis is a unicellular, phototrophic, microalga with a range in size of 10 - 80 μm. It is encased in a heavily silicified cell wall, called the frustule, and is identified by its unique theca, raphe and striations, which distinguish it from other diatoms. They are native to pelagic environments of the Southern Ocean within a temperature range of -1° to 18° C. F. kerguelensis is known to form community chains that consist of 20-100 cells and can be up to 300 μm long.
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Diatom morphology Currently there is no consensus concerning methods for DNA preservation and isolation, the choice of DNA barcodes and PCR primers, nor agreement concerning the parameters of MOTU clustering and their taxonomic assignment. Sampling and molecular steps need to be standardize through development studies. One of the major limitation is the availability of reference barcodes for diatoms species. The reference database of bioindicator taxa is far from complete despite the constant efforts of numerous national barcoding initiatives a lot of species are still lacking barcode information.
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Apicomplexans are some of the most successful specific parasites to animals (including the genus Plasmodium, the malaria parasites). Water molds cause several plant diseases - it was the water mold Phytophthora infestans that caused the Irish potato blight that led to the Great Irish Famine. However, many others are vital members of our ecosystem. Diatoms are one of the major photosynthetic producers, and as such produce much of the oxygen that we breathe, and also take in much of the carbon dioxide from the atmosphere.
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The use of organ- and fossil-genera was abandoned with the St Louis Code (), replaced by "morphotaxa". The situation in the Vienna Code of 2005 was that any plant taxon whose type is a fossil, except Diatoms, can be described as a morphotaxon, a particular part of a plant preserved in a particular way. Although the name is always fixed to the type specimen, the circumscription (i.e. range of specimens that may be included within the taxon) is defined by the taxonomist who uses the name.
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The natural bridge, as seen at dusk. The intertidal zone is home to mussels, sea stars, sea anemones and limpets, seen here being studied by children. Natural Bridges State Beach is named for the naturally occurring mudstone bridges that were carved by the Pacific Ocean into cliffs that jutted out into the sea. The arches formed over a million years ago when a combination of silt, clay and diatoms were solidified into a mixture of stone that formed the three original arches of the beach.
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Hilsa kelee, called the kelee shad, fivespot herring and the razorbelly, is a species of shad native to the coasts and estuaries of the Indian Ocean and the western Pacific, generally in tropical waters. It feeds on diatoms and dinoflagellates, and any other small plankton that it can trap in its gillrakers. Some individuals can reach 35 cm, but most are around 16.5 cm. Hilsa kelee is currently considered the only species in the genus Hilsa, although other species have been included in the genus previously.
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Image of Pseudo-nitzschia Pseudo-nitzschia australis are a part of the genus which are bilaterally symmetrical diatoms with a protective cell wall layer called a silica. Their body plan is such that cells overlap with adjacent cells, allowing them to form chains. The cells are needle shaped, and the overlap between cells can be between one- third to one-half each cell length. Their total body length can be from 68-144 μm long and their width can range from 3-8 μm wide.
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The term protista was first used by Ernst Haeckel in 1866. Protists were traditionally subdivided into several groups based on similarities to the "higher" kingdoms such as: ;Protozoa: These unicellular "animal-like" (heterotrophic, and sometimes parasitic) organisms are further sub-divided based on characteristics such as motility, such as the (flagellated) Flagellata, the (ciliated) Ciliophora, the (phagocytic) amoeba, and the (spore-forming) Sporozoa. ;Protophyta: These "plant-like" (autotrophic) organisms are composed mostly of unicellular algae. The dinoflagelates, diatoms and Euglena-like flagellates are photosynthetic protists.
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The Military Geology Unit was key in determining the origin of Japanese Fu-Go balloon bombs.Mange, Maria and Wright, David, 2007, Heavy Minerals In Use. p. 954. Working with Colonel Sidman Poole of US Army Intelligence, the researchers of the Military Geological Unit began microscopic and chemical examination of the sand from the sandbags to determine types and distribution of diatoms and other microscopic sea creatures, and its mineral composition. The sand could not be coming from American beaches, nor from the mid-Pacific.
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Ligia exotica is both a grazer on microalgae and diatoms and a scavenger on plant remains and detritus. In the eastern United States, where it is considered to be invasive, it seems to be the dominant invertebrate in its habitat. The impact of this on competing organisms and its contribution to the diet of predators has not been properly evaluated, however the NEMESIS database suggests it is not likely to be of much significance.National Exotic Marine and Estuarine Species Information System Retrieved December 3, 2011.
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Diatoms are found in benthic and pelagic environments of the bay, and also as epiphytes living on other marine plants. There is a total of 336 diatom taxa identified in the bay, 50 of which are planktonic, 123 of which are epiphytic, and 282 of which are benthic (about 111 taxa overlap the epiphytic and benthic categories). Benthic diatom assemblage distributions correspond to sediment type, grain size, and wave energy. Sea lettuce, a macroalgae otherwise known as green nori, grows usually only in the summer.
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A predator and omnivore, E. picta perches on a coral or stone waiting for small fish or other prey to come within range. Its colouring provides cryptic camouflage when it is among the fronds of L. pertusa. It also feeds on diatoms, foraminiferans, radiolarians, copepods, arrow worms and marine snow. In one study, while observing the seabed with a remotely operated underwater vehicle, researchers found this squat lobster in association with the coral at a wreck site in the Gulf of Mexico at a depth of about .
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In addition the tentacles, whose surface area is increased by microvilli (small hairs and pleats), absorb organic compounds dissolved in the water. Unwanted particles may be flicked away by tentacles or shut out by closing the mouth. A study in 2008 showed that both encrusting and erect colonies fed more quickly and grew faster in gentle than in strong currents. In some species the first part of the stomach forms a muscular gizzard lined with chitinous teeth that crush armored prey such as diatoms.
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Apart from the first characteristics of the lake district, this research yielded (in collaboration with specialists as Bart van de Vijver or Jiří Komárek) important results in taxonomy, ecology, ecophysiology and biogeography of Antarctic cyanobacteria, diatoms and green algae. Recently, she became a member of the Cryosphere Ecology Group formed at the Charles University in Prague. In addition to her academic research publications, she has also written chapters in monographs, popular science articles, reports from Antarctic expeditions, and lake ecosystems at James Ross Island.
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In the early 20th century, phytoplankton was dominated by green algae, diatoms, and carapace flagellates with a smaller amount of cyanobacteria, a normal distribution for lakes rich in nutrients. By 2000, the biomass was almost exclusively composed of cyanobacteria, most of them non-poisonous "thin filaments" and anabacena the only species being able to fixate nitrogen. Today, the only reminder of the 1990s is the relatively frequent occurrence of the carapace flagellate Ceratium hirundinella. Zooplankton, moderate levels of rotifers and copepods, have shown insignificant variations with time.
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Upwelling of deep water under the sea ice brings substantial amounts of nutrients. As the ice melts, the melt water provides stability and the critical depth is well below the mixing depth, which allows for a positive net primary production. As the sea ice recedes epontic algae dominate the first phase of the bloom, and a strong bloom dominate by diatoms follows the ice melt south. Another phytoplankton bloom occurs more to the north near the Antarctic convergence, here nutrients are present from thermohaline circulation.
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Most common phytoplankton species are filamentous cyanobacteria and diatoms, while zooplankton are represented by daphnia and copepods. Common aquatic plants in the water column include rigid hornwort and yellow water-lily coupled with a presence of Nuttall's waterweed, frogbit, common duckweed, white waterlily, amphibious bistort, and four species of pondweeds.Vattenprogram, p 13.4-13.6 An inventory of lakebed fauna in 1997 documented 47 species/taxa, predominately freshwater gastropods, beetles, and dragonflies. The same year, perch, roach, bleak, and a few other species were documented in the lake.
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In general, diatoms flourish in nutrient-rich waters with high light penetration. Some species of Pseudo-nitzschia can grow in a broad temperature range (4-20°C), making it possible for them to inhabit a diverse range of habitats. Pseudo-nitzschia species have been observed in all oceans of the world, including the Arctic and Antarctic. In North America, they have been documented along the Pacific coast from Canada to California, along the Atlantic Northeast coast of Canada, North Carolina, and the Gulf of Mexico.
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Western chorus frogs not only come out at night to chorus, but also to feed. The diet of an adult consists of small invertebrates and arthropods, such as small flies, mosquitoes, ants, small beetles, moths and caterpillars, grasshoppers, and spiders, only if they are small enough. Froglets (the transition or metamorphic phase between tadpole and frog) will feed on smaller prey, such as mites, midges, and springtails. Tadpoles feed on periphyton, filamentous algae, diatoms, and pollen in or on the surface of the water.
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Nutrients dynamics vary in the river basin from the headwaters to the main river and dams, to finally reaching the Columbia River estuary and ocean. Upstream in the headwaters, salmon runs are the main source of nutrients. Dams along the river impact nutrient cycling by increasing residence time of nutrients, and reducing the transport of silicate to the estuary, which directly impacts diatoms, a type of phytoplankton. The dams are also a barrier to salmon migration, and can increase the amount of methane locally produced.
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An NMR analysis of whole algal cells which were cultivated in autotrophic growth reports evidence of the presence of cellulose in the cell wall and of mobile chrysolaminarin, probably accumulated in solution in vacuoles inside the cell. Comparison between the lipid metabolic genes of N. gaditana and of red/green/brown algae and diatoms provided some insights into the exemplary lipid production of Nannochloropsis cultures. The comparisons indeed highlighted the presence of an expanded repertoire of some of the genes involved in TAG assembly in Nannochloropsis.
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The heterokonts or stramenopiles (formally, Heterokonta or Stramenopiles) are a major line of eukaryotes. Most are algae, ranging from the giant multicellular kelp to the unicellular diatoms, which are a primary component of plankton. Other notable members of the Stramenopiles include the (generally) parasitic oomycetes, including Phytophthora of Great Famine of Ireland infamy and Pythium which causes seed rot and damping off. The name "heterokont" refers to the type of motile life cycle stage, in which the flagellated cells possess two differently shaped flagella (see zoospore).
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Mastigonemes are manufactured from glycoproteins in the cell's endoplasmic reticulum before being transported to the anterior flagella's surface. When the straminipilous flagellum moves, the mastigonemes create a retrograde current, pulling the cell through the water or bringing in food. The mastigonemes have a peculiar tripartite structure, which may be taken as the defining characteristic of the heterokonts, thereby including a few protists that do not produce cells with the typical heterokont form. Mastigonemes have been lost in a few heterkont lines, most notably the diatoms.
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The orange band surgeonfish feeds on detritus and on algae growing on the seabed, as well as the film of diatoms and filamentous algae that grows on sand and other substrates. It often forms schools with parrotfish, tangs and other species of surgeonfish, which all have similar diets; their grazing is important in maintaining biodiversity by keeping rocks free from excessive growth of algae so that coral larvae can find suitable habitat to settle. The fish can change colour from dark to pale almost instantaneously.
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Microscopic close-up of clumping cat litter, showing the fossilized remains of diatoms Litter clumps were first developed by using calcium bentonite clay. This was manufactured in the UK in the 1950s by the Fuller's Earth Union (FEU), which later became a part of Laporte Industries Ltd. Subsequently in America, clumping bentonite was developed in 1984 by biochemist Thomas Nelson. Most are made from granulated bentonite clay, which clumps together when wet and forms a solid mass separate from the other litter in the box.
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Some components of an ecosystem are more sensitive to deposition than others; therefore, critical loads can be developed for a variety of ecosystem components and responses, including (but not limited to) shifts in diatoms, increases in invasive grass species, changes in soil chemistry, decreased forest health, altered and reduced biodiversity, and lake and stream acidification. The history, terminology, and approach used to calculate critical loads differ by region and country. The differences between approaches used by European countries and in the U.S. are discussed below.
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Coloration is dark bluish grey on top and lighter gray on the bottom, and the head can be brownish shading to light grey around the lip and the jaw. Skin discoloration might be caused by diatoms .They might have white oval scars possibly caused by cookie-cutter sharks. Adult males can also have long white ‘scratch’ scars. Males reach at least 4.4 m (14 ft 5 in) and 800 kg (1,800 lb), whereas females reach at least 4.6 m (15') and 1 tonne (2200 pounds).
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Ancient lakes allow scientists to study the mechanisms of environmental changes over glacial- interglacial timescales. Evolutionary characteristics including sexual selection, adaptive radiation and punctuated equilibrium are studied in ancient lakes due to their prolonged existence and general geographic isolation. Most of the research has been associated with the endemic fauna and diatoms that exists in these isolated lakes, concentrating on Lake Baikal, the Caspian Sea and the African Great Lakes. Information is derived from the associations of the fluvial-lacustrine, fluctuating profundal and evaporative facies.
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Reservoir size of silicate rocks, as discussed in the sources section, is 1.5x1021 Tmol. Siliceous organisms in the ocean, such as diatoms and radiolaria, are the primary sink of dissolved silicic acid into opal silica. Once in the ocean, dissolved Si molecules are biologically recycled roughly 25 times before export and permanent deposition in marine sediments on the seafloor. This rapid recycling is dependent on the dissolution of silica in organic matter in the water column, followed by biological uptake in the photic zone.
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Members of the Roseobacter clade are widely associated with marine phytoplankton such as dinoflagellates and diatoms in the water column as well as shallow sediments. They play important roles in the carbon cycle by assimilating dissolved organic matter produced by phytoplankton and also in the sulfur cycle by removing DMS from the algal osmolyte dimethylsulfoniopropionate (DMSP).Wang H, Tomasch J, Jarek M, Wagner-Dobler I: A dual-species co-cultivation system to study the interactions between Roseobacters and dinoflagellates. Frontiers of Microbiology 2014, 5:311.
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Conjugation is a convenient means for transferring genetic material to a variety of targets. In laboratories, successful transfers have been reported from bacteria to yeast, plants, mammalian cells, diatoms and isolated mammalian mitochondria. Conjugation has advantages over other forms of genetic transfer including minimal disruption of the target's cellular envelope and the ability to transfer relatively large amounts of genetic material (see the above discussion of E. coli chromosome transfer). In plant engineering, Agrobacterium-like conjugation complements other standard vehicles such as tobacco mosaic virus (TMV).
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Air-sea exchange of Previous instances of biological carbon sequestration triggered major climatic changes, lowering the temperature of the planet, such as the Azolla event. Plankton that generate calcium or silicon carbonate skeletons, such as diatoms, coccolithophores and foraminifera, account for most direct sequestration. When these organisms die their carbonate skeletons sink relatively quickly and form a major component of the carbon-rich deep sea precipitation known as marine snow. Marine snow also includes fish fecal pellets and other organic detritus, and steadily falls thousands of meters below active plankton blooms.
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The creek chubsucker is a bottom feeding forager in freshwater streams. The adults are generally solitary, and can be found near the substrate of slowly flowing streams where they forage for food.Taylor, Christopher M., "Fish Species Richness and Incidence Patterns in Isolated and Connected Stream Pools: Effects of Pool Volume and Spatial Position." Oecologia, Vol. 110, No. 4 (1994): 560-566 Most of the prey items making up the creek chubsucker's diet include microcrustacea (Copepod, Cladocera, Chironomidae larvae etc.), organic detritus, algae, diatoms, small clams, and Diptera larvae.
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Some bacteria interact with diatoms, and form a critical link in the cycling of silicon in the ocean. One anaerobic species, Thiomargarita namibiensis, plays an important part in the breakdown of hydrogen sulfide eruptions from diatomaceous sediments off the Namibian coast, and generated by high rates of phytoplankton growth in the Benguela Current upwelling zone, eventually falling to the seafloor. Bacteria-like Archaea surprised marine microbiologists by their survival and thriving in extreme environments, such as the hydrothermal vents on the ocean floor. Alkalotolerant marine bacteria such as Pseudomonas and Vibrio spp.
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Even prior to the nucleic acid methods employed today it was known that in the presence of chaotropic agents, such as sodium iodide or sodium perchlorate, DNA binds to silica, glass particles or to unicellular algae called diatoms which shield their cell walls with silica. This property was used to purify nucleic acid using glass powder or silica beads under alkaline conditions.Marko MA, Chipperfield R, Birnboim HC. A procedure for the large-scale isolation of highly purified plasmid DNA using alkaline extraction and binding to glass powder. Anal Biochem.
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Red algae are not only key members of marine and freshwater aquatic environments but they are sources for important human foods such as dulse and sushi wrap, and have a multitude of pharmaceutical and industrial uses (e.g., agarose and carrageenans). Perhaps most important is the role red algae played in symbiogenesis. A red alga was the ancient (>1 billion years ago) donor of the plastid in chlorophyll c-containing algae (heterokonta or stramenophiles) that rose to prominence in marine ecosystems after the end of Permian with groups such as diatoms currently providing ca.
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Scale diagram of the layers of the pelagic zone In the deep ocean, the waters extend far below the epipelagic zone, and support very different types of pelagic fishes adapted to living in these deeper zones.Moyle and Cech, 2004, page 585 In deep water, marine snow is a continuous shower of mostly organic detritus falling from the upper layers of the water column. Its origin lies in activities within the productive photic zone. Marine snow includes dead or dying plankton, protists (diatoms), fecal matter, sand, soot and other inorganic dust.
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Vertical migration, or movement of phytoplankton within the water column, contributes to the establishment of the DCM due to the diversity of resources required by the phytoplankton. Dependent on factors like nutrients and available light, some phytoplankton species will intentionally move to different depths to fulfill their physiological requirements. A mechanism employed by certain phytoplankton, such as certain species of diatoms and cyanobacteria, is to regulate their own buoyancy to move through the water column. Other species such as dinoflagellates use their flagella to swim to their desired depth.
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Adult sprats feed on copepods such as Calanus, Pseudocalanus and Temora while juveniles feed on the eggs and larvae of these crustaceans, and on diatoms. Breeding takes place at any time of year but peaks between December and April in the Mediterranean and between April and August in the Baltic and northeastern Atlantic. Spawning may take place in inshore waters or up to off the coast. This fish is sometimes parasitised by a copepod, the sprat eye-maggot (Lernaeenicus sprattae) which burrows into its eye and causes loss of visual acuity or even blindness.
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The group Oomycetes, also known as water molds, are saprotrophic plant pathogens like fungi. Until recently they were widely believed to be fungi, but structural and molecular evidence has led to their reclassification as heterokonts, related to autotrophic brown algae and diatoms. Unlike fungi, oomycetes typically possess cell walls of cellulose and glucans rather than chitin, although some genera (such as Achlya and Saprolegnia) do have chitin in their walls. The fraction of cellulose in the walls is no more than 4 to 20%, far less than the fraction of glucans.
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Another key piece of evidence for a processional control on the North African Monsoon can be found in the deposits of freshwater diatoms in the tropical Atlantic. Ocean cores from the tropical Atlantic have been found to have distinct layers of the freshwater diatom Aulacoseira Granulata also known as Melosira Granulata. These layers occur on a 23,000 year cycle that lags the maximum in precession insolation by roughly 5000 to 6000 years. To explain these cyclic freshwater diatom deposits we have to look inland at the Sahara region of Africa.
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Around the time of the insolation maximum in the precession cycle the North African Monsoon is at its strongest and the Sahara region becomes dominated by large monsoonal lakes. Then as time progress toward the insolation minima, these lakes begin to dry out due to weakening North African Monsoon. As the lakes dry up thin sediment deposits containing freshwater diatoms are exposed. Finally, when the prevailing northeasterly winds arrive during winter, the freshwater diatom deposits in the dried lake beds are picked up as dust and carried thousands of kilometers out into the tropical Atlantic.
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Commonly found in oligotrophic environments, diatoms within the genera Hemiaulus and Rhizosolenia form symbiotic associations with filamentous cyanobacteria in the species Richelia intracellularis. As an endophyte in up to 12 species of Rhizosolenia, R. intracellularis provides fixed nitrogen to its host via the terminally-located heterocyst. Richella-Rhizosolenia symbioses have been found to be abundant within the nitrogen-limited waters of the Central-Pacific Gyre. Several field studies have linked the occurrence of phytoplankton blooms within the gyre to an increase in nitrogen fixation from Richella-Rhizosolenia symbiosis.
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Target levels of toxins are set by the EC and fisheries can be closed to protect the public health if concentrations of toxins exceed these limits. In 2007 scallop beds along the west coast of Scotland were affected by a bloom which caused Amnesic Shellfish Poisoning (ASP). Amnesic Shellfish Poisoning is caused by domoic acid which is produced naturally by marine diatoms of the genus Pseudonitzschia. If molluscan shellfish filter large amounts of these algae it can lead to illness such as gastrointestinal symptoms, muscular aches, cramps and temporary loss of short- term memory.
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Dr. Gonzalez also reconstructed the environment of Lake Texcoco around the time of Tepexpan Man by analyzing sediments and fossils from the area. Dr. Gonzalez and her team analyzed sand, clay, and volcanic ash, as well as fossils of diatoms (microscopic algae) and ostracods (a form of small crustacean). When Tepexpan Man was alive, the lake was very deep, full of fish, and surrounded by trees. The environment surrounding Lake Texcoco experienced major changes over the past 20,000 years including several volcanic eruptions, changing water levels, and numerous types of vegetation.
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When the lophophore is extended, cilia (little hairs) on the sides of the tentacles draw water down between the tentacles and out at the base of the lophophore. Shorter cilia on the inner sides of the tentacles flick food particles into a groove in a circle under and just inside the tentacles, and cilia in the groove push the particles into the mouth. Phoronids direct their lophophores into the water current, and quickly reorient to maximize the food-catching area when currents change. Their diet includes algae, diatoms, flagellates, peridinians, small invertebrate larvae, and detritus.
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It mainly consumes red and green algae and diatoms which it catches by raising one or more of its arms into the passing water current while keeping its disc concealed. If an arm is attacked by a predator it can easily break off in a process known as autotomy, and the brittle star can later regenerate a new limb. The sexes are separate in Ophionereis reticulata and spawning takes place once a year. The ophiopluteus larvae are planktonic and after passing through several larval stages, settle on the seabed and undergo metamorphosis into juveniles.
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Diatoms are used to as a diagnosis tool for drowning in forensic practices. The diatom test is based on the principle of diatom inhalation from water into the lungs and distribution and deposition around the body. DNA methods can be used to confirm if the cause of death was indeed drowning and locate the origin of drowning. Diatom DNA metabarcoding, provides the opportunity to quickly analyse the diatom community present within a body and locate the origin of drowning and investigate if a body may have been moved from one place to another.
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Calanus finmarchicus is most commonly found in the North Sea and the Norwegian Sea. It is also found throughout the colder waters of the North Atlantic, especially off the coast of Canada, in the Gulf of Maine, and all the way up to western and northern Svalbard. Calanus finmarchicus is one of the most commonly found species of zooplankton in the subarctic waters of the North Atlantic. Sometimes confused with C. helgolandicus and C. glacialis, C. finmarchicus is a large planktonic copepod whose chief diet includes diatoms, dinoflagellates, and other microplanktonic organisms.
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The arrow goby occurs in sand or mud substrates, where it uses burrows created by invertebrates as shelters when it is threatened and as a refuge at low tide. Some of the species which make burrows used by arrow gobies include the shrimps Neotrypaea californiensis and Upogebia pugettensis and the fat innkeeper worm Urechis caupo. It is a common species of estuaries, lagoons and tidal sloughs, and it has been reported in freshwater. The adults feed on diatoms, green algae, tintinnids, eggs and young of the host shrimp or prawn.
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In 2017, Aro became a leader of NordAqua, a Nordic Centre of Excellence funded by NordForsk to develop bioeconomy knowledge and technologies for the period 2017–2022. Aro's research interests lie primarily in the regulation of photosynthesis, the process by which primary producers such as plants convert an abiotic energy source such as light into organic compounds. Her lab studies the evolution of thylakoid light harvesting by photosystem membrane complexes in model organisms such as cyanobacteria, Chlamydomonas reinhardtii, diatoms, Physcomitrella patens, ferns, Arabidopsis thaliana, and spruce. Her applied research interests lie in renewable energy.
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The Center's scientists are recognized around the world for their expertise in landscape ecology and the application of GIS technology for addressing natural resource questions.Johnson, L.B. and G. E. Host. 2010. Recent developments in landscape approaches for the study of aquatic ecosystems, Journal of the North American Benthological Society 29(1): 41-66 (25th Anniversary Issue). A field station was established in Ely, Minnesota, in 1999 to study microscopic algae (diatoms) as indicators of water quality and for paleolimnology research to understand environmental trends through analysis of sediment profiles.
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Navicula is a genus of boat-shaped diatom algae, comprising over 1,200 species. Navicula is Latin for "small ship", and also a term in English for a boat-shaped incense-holder.Oxford English Dictionary, "Navicula. 3" Diatoms -- eukaryotic, primarily aquatic, single-celled photosynthetic organisms -- play an important role in global ecology, producing about a quarter of all the oxygen within Earth's biosphere, often serving as foundational organisms, or keystone species in the food chain of many environments where they provide a staple for the diets of many aquatic species.
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The amoeboid cells of the former combine to form a giant multinucleate organism, while the cells of the latter live separately until food runs out, at which time the amoebae aggregate to form a multicellular migrating "slug" which functions as a single organism. Other organisms may also present amoeboid cells during certain life-cycle stages, e.g., the gametes of some green algae (Zygnematophyceae) and pennate diatoms, the spores (or dispersal phases) of some Mesomycetozoea,Taylor, J. W. & Berbee, M. L. (2014). Fungi from PCR to Genomics: The Spreading Revolution in Evolutionary Biology.
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A preliminary report states that ancient carcasses of crustaceans and a tardigrade were isolated from the sediment samples. The lake water samples contains enough oxygen to support aquatic animals, and bacteria are present with a density of at least 10,000 cells per millilitre. Other ancient organisms retrieved from the sediments include shells of diatoms (a photosynthetic algae) and thread-like plants or fungi. How the crustaceans and tardigrade reached Lake Mercer is a matter of debate, but the scientists suspect that the gradual uplift of the continent transformed shallow ocean bays into isolated lakes.
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The biological function of this structural coloration is not clear, but it is speculated that it may be related to communication, camouflage, thermal exchange and/or UV protection. Diatoms build intricate hard but porous cell walls called frustules composed primarily of silica. This siliceous wall can be highly patterned with a variety of pores, ribs, minute spines, marginal ridges and elevations; all of which can be used to delineate genera and species. The cell itself consists of two halves, each containing an essentially flat plate, or valve and marginal connecting, or girdle band.
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São Paulo 16, 5–215 (1951). While consuming diatoms, B. solaris and P. paranygulus, in a process not yet discovered, extract plastids from their prey, incorporating them supepidermally, while separating and digesting the frustule and remainder of the diatom. In B. solaris the extracted plastids, or kleptoplasts, continue to exhibit functional photosynthesis for a short period of roughly 7 days. As the two groups are not sister taxa, and the trait is not shared among groups more closely related, there is evidence that kleptoplasty evolved independently within the two taxa.
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In general, dissolved organic carbon (DOC) is introduced into the ocean environment from bacterial lysis, the leakage or exudation of fixed carbon from phytoplankton (e.g., mucilaginous exopolymer from diatoms), sudden cell senescence, sloppy feeding by zooplankton, the excretion of waste products by aquatic animals, or the breakdown or dissolution of organic particles from terrestrial plants and soils. Bacteria in the microbial loop decompose this particulate detritus to utilize this energy-rich matter for growth. Since more than 95% of organic matter in marine ecosystems consists of polymeric, high molecular weight (HMW) compounds (e.g.
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Amnesic shellfish poisoning (ASP) is an illness caused by consumption of the marine biotoxin called domoic acid. In mammals, including humans, domoic acid acts as a neurotoxin, causing permanent short-term memory loss, brain damage, and death in severe cases. This toxin is produced naturally by marine diatoms belonging to the genus Pseudo-nitzschia and the species Nitzschia navis- varingica. Nitzschia navis-varingica When accumulated in high concentrations by shellfish during filter feeding, domoic acid can then be passed on to birds, marine mammals, and humans by consumption of the contaminated shellfish.
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Unusually, some stromatoliths are formed out of halite rather than the more common aragonite/carbonate although aragonite and silica are their most important building materials. The dominant bacteria in the stromatoliths are Microcoleus cyanobacteria and deinococci in the surface; there are also eukaryotic algae, diatoms. Other taxa include Desulfobacterales, Rhodobacteraceae and Spirochaetes and mostly represent novel lineages; the extreme conditions of these high elevation lakes lead to high extremophile diversity. Some of the Laguna Socompa stromatoliths are classified as Conophyton stromatoliths, which are otherwise only known as Precambrian (over 541 ± 1 million years old) fossils.
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Thyone fusus is a suspension feeder, consuming diatoms, single- cell algae and drifting organic particles, as well as zooplankton such as copepods, ostracods, protozoans, nematodes, jellyfish and larvae. The two ventral feeding tentacles are much shorter than the others and have forked ends. Each large tentacle in turn shrinks and folds and is pushed into the mouth. A small tentacle is held close to the mouth and cooperates with each of the others by scraping off any food particles that are still adhering to the large one when it is withdrawn from the mouth.
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He invented ways to synchronize the cell division cycle of diatoms. He showed that silicon activates the gene coding for the polymerase enzyme that copies diatom DNA. He was also interested in the toxic and pathological effects of polysilicates, such as talc and asbestos, on mammalian cells in tissue culture, and was the first to do tissue culture at Scripps. He spent a one-year sabbatical at the University of Swansea studying the effects of polysilicates on mammalian cells, and published papers on the uptake of silicic acid by rat liver mitochondria.
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Character of the kingdom of Protists.) In 1938, Herbert Copeland resurrected Hogg's label, arguing that Haeckel's term Protista included anucleated microbes such as bacteria, which the term "Protoctista" (literally meaning "first established beings") did not. In contrast, Copeland's term included nucleated eukaryotes such as diatoms, green algae and fungi. This classification was the basis for Whittaker's later definition of Fungi, Animalia, Plantae and Protista as the four kingdoms of life. The kingdom Protista was later modified to separate prokaryotes into the separate kingdom of Monera, leaving the protists as a group of eukaryotic microorganisms.
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Lake Trekanten viewed from Liljeholmen. In late summer, phytoplankton stock is dominated by green algae paired equal levels of diatoms, cyanobacteria, and a species of eutroph carapace flagellate (Ceratium hirundinella). Several of the blue green algae present in the lake are potentially poisonous and, notwithstanding non-alarming levels, therefore carefully monitored near the bathe. Lacking soft and shallow bottom areas near the shore, the lake contains only commonplace vegetation, save for the population of crack willow and the hybrid between white willow and bay willow found on the southern shore.
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Tomopteris, a holoplanktic polychaete worm with an unusual yellow bioluminescence that emanates from its parapodia Holoplankton are organisms that are planktic (they live in the water column and cannot swim against a current) for their entire life cycle. Holoplankton can be contrasted with meroplankton, which are planktic organisms that spend part of their life cycle in the benthic zone. Examples of holoplankton include some diatoms, radiolarians, some dinoflagellates, foraminifera, amphipods, krill, copepods, and salps, as well as some gastropod mollusk species. Holoplankton dwell in the pelagic zone as opposed to the benthic zone.
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In 1883 he married Olga Petrovna Sultanova, and became a lecturer at the University of St Petersburg. In 1886 they emigrated from Russia for unexplained reasons, possibly connected to the paedophilia for which he was later prosecuted. The family set up home in Crimea, where he found work as a botanist looking at varieties of grape; he also created a substantial collection of diatoms from the Black Sea. In 1898, he left his wife and young son in Crimea and emigrated to America, where he took the name "William Adler".
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These frogs can be identified by their rough skin, horizontal pupils, fully webbed hind feet, and their habit of jumping into moving water. Tadpoles of this species, though, resemble those of the western toad, Bufo boreas. R. boylii as tadpoles have fairly flattened tails that lack color at the end and are the tallest in the midsection. The mouths of the tadpoles are made for suction to rocks, with labial teeth rows used for scraping algae and diatoms, unicellular algae with cells walls that contain silica, off of the rocks to which they are clinging.
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Aurelia aurita and other Aurelia species feed on plankton that includes organisms such as mollusks, crustaceans, tunicate larvae, rotifers, young polychaetes, protozoans, diatoms, eggs, fish eggs, and other small organisms. Occasionally, they are also seen feeding on gelatinous zooplankton such as hydromedusae and ctenophores. Both the adult medusae and larvae of Aurelia have nematocysts to capture prey and also to protect themselves from predators. The food is caught with its nematocyst-laden tentacles, tied with mucus, brought to the gastrovascular cavity, and passed into the cavity by ciliated action.
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The Farlow Herbarium of Cryptogamic Botany is an herbarium and library at Harvard University with about 1,400,000 specimens, including approximately 75,000 types, of lichens, fungi, bryophytes, diatoms, and algae.Farlow Herbarium, Harvard University, Farlow Herbarium It grew from the 1919 bequest of William Gilson Farlow of his personal herbarium and library to Harvard. It grew further from additional bequests from Roland Thaxter, and specimens, manuscripts, correspondence, illustrations, and field notes from other notable researchers such as E. B. Bartram, E. A. Burt, W. H. Weston Jr., D. H. Linder, and I. M. Lamb.
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The lifespan of the fish is estimated to be 6 to 7 years It is commonly found in standing or slowly flowing open water of lakes, ponds, rivers, and shallow swamps where vegetation is present. It is occasionally found in sandy or rocky streams, or shallow flood plains. It feeds from mid-water and surface waters on fish, insects, crustaceans, ostracods, snails, seeds, leaves, roots, diatoms, algae, and fruit. It has been noted to feed on the fish species Elephant snout (Hyperopisus bebe) and Nile tilapia (Oreochromis niloticus).
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They are then joined by multicellular forms including Fragilaria crotonensis, Nitzschia fruticosa and Skeletonema potamos, as well as green algae which form star-shaped or prostrate colonies. Whereas the total biomass is low in the upper reaches, the biodiversity is high, with more than 250 taxa at Orléans. At high flows and in the upper reaches the fraction of the green algae decrease and the phytoplankton is dominated by diatoms. Heterotrophic bacteria are represented by cocci (49%), rods (35%), colonies (12%) and filaments (4%) with a total density of up to cells per litre.
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Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping, including species from multiple distinct clades. Included organisms range from unicellular microalgae, such as Chlorella and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to 50 m in length. Most are aquatic and autotrophic and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem, which are found in land plants.
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The decline is attributed to sea surface temperature increases. A separate study found that diatoms, the largest type of phytoplankton, declined more than 1 percent per year from 1998 to 2012, particularly in the North Pacific, North Indian and Equatorial Indian oceans. The decline appears to reduce pytoplankton's ability to sequester carbon in the deep ocean. Fertilization offers the prospect of both reducing the concentration of atmospheric greenhouse gases with the aim of slowing climate change and at the same time increasing fish stocks via increasing primary production.
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There is a variation in nutrient acquisition among Polykrikos species as some exclusively rely on photosynthesis, some are mixothrophs, while some are obligate heterotrophs which makes Polykrikos a useful group to study for organellar evolution. Early-branching polykrikoids, Polykrikos geminatum and P. hartmanii, have three-membrane plastids with triple stacked thylakoids that are indicative of secondary peridinin-type plastids common for dinoflagellates. However, mixothrophic P. lebouriae, phylogenetically nested among heterothropic polykrikoids, has plastids atypical of dinoflagellates. It has two membranes and contain the double-stacked thylakoids that are found in diatoms and haptophytes.
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The former is known as PSII, the latter is PSI. PSI contains only chlorophyll "a", PSII contains primarily chlorophyll "a" with most of the available chlorophyll "b", among other pigment. These include phycobilins, which are the red and blue pigments of red and blue algae respectively, and fucoxanthol for brown algae and diatoms. The process is most productive when the absorption of quanta are equal in both the PSII and PSI, assuring that input energy from the antenna complex is divided between the PSI and PSII system, which in turn powers the photochemistry.
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In some species of Bryozoa, the first part of the stomach forms a muscular gizzard lined with chitinous teeth that crush armoured prey such as diatoms. Wave-like peristaltic contractions then move the food through the stomach for digestion. The limpet rasps algae from rocks using teeth with the strongest known tensile strength of any biological material Molluscs have a structure called a radula which bears a ribbon of chitinous teeth. However, these teeth are histologically and developmentally different from vertebrate teeth and are unlikely to be homologous.
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In 1957, she made the first regional study of phytoplankton in New Zealand. Later in life, she focused more on aquatic botany, and was appointed a research scientist on freshwater algae in the Botany Division of the Department of Scientific and Industrial Research (DSIR). In her career, she wrote over fifty papers and several books, including Marine Phytoplankton in New Zealand Waters and Checklists of the Freshwater Diatoms of New Zealand. Cooper also published Micro Algae - Microscopic Marvels which she writes to appeal to a more popular readership.
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Growth is also favored at higher temperatures which enable Microcystis species to outcompete diatoms and green algae, and potentially allow development of toxins. Based on environmental trends, models and observations suggest cyanobacteria will likely increase their dominance in aquatic environments. This can lead to serious consequences, particularly the contamination of sources of drinking water. Cyanobacteria can interfere with water treatment in various ways, primarily by plugging filters (often large beds of sand and similar media) and by producing cyanotoxins, which have the potential to cause serious illness if consumed.
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Most species are filter feeders that sieve small particles, mainly phytoplankton (microscopic floating plants), out of the water. The freshwater species Plumatella emarginata feeds on diatoms, green algae, cyanobacteria, non-photosynthetic bacteria, dinoflagellates, rotifers, protozoa, small nematodes, and microscopic crustaceans. While the currents that bryozoans generate to draw food towards the mouth are well understood, the exact method of capture is still debated. All species also flick larger particles towards the mouth with a tentacle, and a few capture zooplankton (planktonic animals) by using their tentacles as cages.
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A red tide off the coast of San Diego, California The other types of algae are diatoms and dinoflagellates, found primarily in marine environments, such as ocean coastlines or bays, where they can also form algal blooms, commonly called red tides. Red tides, however, may be a natural phenomenon,FAQs about red tides, Texas Parks & Wildlife Department although when they form close to coastlines or in estuaries. They can occur when warmer water, salinity, and nutrients reach certain levels, which then stimulates their growth. Most red tide algae are dinoflagellates.
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Americamysis bahia is found on or just above the seabed, tending to be concentrated in slight depressions and facing towards the current. At night it makes vertical migrations to feed at the surface. Opossum shrimps are omnivores and although the diet of Americamysis bahia in the wild has not been studied, examination of the stomach contents of the closely related Americamysis almyra showed 31% vascular plant debris and 11% copepods and diatoms. In the laboratory it is usually fed on the larvae of the brine shrimp Artemia salina.
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Syneresis has also been proposed as the mechanism of formation of the amorphous silicate composing the frustule of diatoms. In the processing of dairy milk, for example during cheese making, syneresis is the formation of the curd due to the sudden removal of the hydrophilic macropeptides, which causes an imbalance in intermolecular forces. Bonds between hydrophobic sites start to develop and are enforced by calcium bonds which form as the water molecules in the micelles start to leave the structure. This process is usually referred to as the phase of coagulation and syneresis.
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The clam filter-feeds through its siphon, taking mostly phytoplankton, with adults preferring microalgae such as diatoms. It may be an opportunistic feeder, its diet varying according to what is available in its wide range of habitat types. This species is a nutritious and attractive prey item for many kinds of predatory animals, including the green crab, moon snails, starfish, fish, ducks, shorebirds, sea otters, and raccoons. It is a host species for the copepod Mytilicola orientalis, a parasite of mussels which is known as a pest in aquaculture operations.
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The term is commonly used to refer to a subset of the discipline, which is defined as "the study of microscopic objects of macromolecular organic composition (i.e., compounds of carbon, hydrogen, nitrogen and oxygen), not capable of dissolution in hydrochloric or hydrofluoric acids". It is the science that studies contemporary and fossil palynomorphs, including pollen, spores, orbicules, dinocysts, acritarchs, chitinozoans and scolecodonts, together with particulate organic matter (POM) and kerogen found in sedimentary rocks and sediments. Palynology does not include diatoms, foraminiferans or other organisms with siliceous or calcareous exoskeletons.
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Beh also said that DNA evidence for sexual abuse could have been diluted in the water. He further criticised the pathologists' decision to not undertake a diatom test on the body, as diatoms of the nearby water would be found in the body to determine if a person had drowned. The jury concluded that Chan died between the night of 19 September and the following day. They also concluded that she was found naked because she entered the water without clothes on rather than that strong waves had washed the clothes away.
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Pollicipes pollicipes grows in groups on rocks, as well as on the hulls of shipwrecks and on driftwood. It is a filter feeder, living on particles that it can glean from the water passing over its extended cirri; these possess a complex assortment of setae, enabling P. pollicipes to have a varied diet, including diatoms, detritus, large crustaceans, copepods, shrimp and molluscs. The larvae pass through seven free-swimming stages (six nauplii and one cypris) over the course of at least a month. After this time, they settle into the adult, sessile form.
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Ocean basins also serve as repositories for the skeletons of carbonate- and silica-secreting organisms such as coral reefs, diatoms, radiolarians, and foraminifera. Geologically, an oceanic basin may be actively changing size or may be relatively, tectonically inactive, depending on whether there is a moving plate tectonic boundary associated with it. The elements of an active - and growing - oceanic basin include an elevated mid-ocean ridge, flanking abyssal hills leading down to abyssal plains. The elements of an active oceanic basin often include the oceanic trench associated with a subduction zone.
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Analysis of choanoflagellate SITs shows that they are similar to the SIT-type silicon transporters of diatoms and other silica-forming stramenopiles. The SIT gene family shows little or no homology to any other genes, even to genes in non- siliceous choanoflagellates or stramenopiles. This suggests that the SIT gene family evolved via a lateral gene transfer event between Acanthoecids and Stramenopiles. This is a remarkable case of horizontal gene transfer between two distantly related eukaryotic groups, and has provided clues to the biochemistry and silicon-protein interactions of the unique SIT gene family.
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The newly hatched fish larvae are planktonic feeders on small diatoms, as they grow they also feed on zooplankton such a copepods. The adults are mainly herbivorous, feeding mainly on algae including Polysiphonia spp and Sphacelaria spp. but have been observed feeding on ctenophores and scyphozoans in the Spring and early summer within the northern Red Sea, attacking relatively large ctenophores until the disintegrate and on the schypozoan moon jellyfish Aurelia aurita until it sinks to the bottom. S. rivulatus reaches sexual maturity at a length of 13.7 cm.
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Alburnoides bipunctatus, known vernacularly as the schneider, spirlin, bleak, riffle minnow, and others, is a species of small (9-cm average length) freshwater fish in the family Cyprinidae. It is found in Afghanistan, Armenia, Austria, Azerbaijan, Belarus, Belgium, Bulgaria, Czech Republic, Croatia, Estonia, France, Georgia, Germany, Hungary, Iran, Latvia, Lithuania, Moldova, the Netherlands, North Macedonia, Poland, Romania, Russia, Serbia, Slovakia, Slovenia, Switzerland, Turkey, Ukraine, and Uzbekistan. This fish inhabits rivers with very calm waters, and it eats dead insects and insect larvae, diatoms, and crustaceans. It reproduces during April to June.
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Jersey cattle on the Hiruzen Plateau Hiruzen is a dormant, but not extinct, volcano located to the southeast of Mount Daisen. The three peaks of Hiruzen, along with a few smaller peaks, form the Hiruzen volcanic belt, a subset of the Daisen volcanic belt. An eruption of Daisen occurred approximately 350,000 years ago, and created a lake, known as Lake Hiruzenbara, above the Hiruzen Plateau. The lake supported an extensive population of diatoms for nearly 50,000 years, and Diatomaceous soil on the plain reaches deep in some areas.
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Chromista collage 2 Chromista is a biological kingdom consisting of some single-celled and multicellular eukaryotic organisms, which share similar features in their photosynthetic organelles (plastids). It includes all protists whose plastids contain chlorophyll c such as some algae, diatoms, oomycetes, and protozoans. It is probably a polyphyletic group whose members independently arose as separate evolutionary group from the common ancestor of all eukaryotes. As it is assumed the last common ancestor already possessed chloroplasts of red algal origin, the non-photosynthetic forms evolved from ancestors able to perform photosynthesis.
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This group was originally classified among the fungi (the name "oomycota" means "egg fungus") and later treated as protists, based on general morphology and lifestyle. A cladistic analysis based on modern discoveries about the biology of these organisms supports a relatively close relationship with some photosynthetic organisms, such as brown algae and diatoms. A common taxonomic classification based on these data, places the class Oomycota along with other classes such as Phaeophyceae (brown algae) within the phylum Heterokonta. This relationship is supported by a number of observed differences between the characteristics of oomycetes and fungi.
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WHOI scientists at LJL installing a Video Plankton RecorderThis nutrient rich upwelling such as occurs in the Gulf of Panama, can stimulate Plankton production leading to blooms of centric, colonial, and penate diatoms and dinoflagellates. Zooplankton populations often respond to this by subsequently increasing growth and reproduction rates. Scientists are now able to quantify the abundance and diversity of these microscopic organisms in-situ with sensors such as the Video Plankton Recorder (a specialized underwater microscope and imaging system).Davis, CS, Hu, Q, SM Gallager, x Tang, C Ashjian.
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Cipangopaludina chinensis feeds non-selectively on organic and inorganic bottom material as well as benthic and epiphytic algae, mostly by scraping, but diatoms are probably the most nutritious food it ingests at sites in eastern North America. This species is primarily an algae eater in an aquarium context. These snails are popular in freshwater aquariums because they do not eat fish eggs or plants, they do not overpopulate the aquarium, and they close up if there is a water problem, giving people an indication that something is wrong a few weeks before the fish die.
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Similar in many ways to the Alvord chub, the Borax Lake species has a longer, wider, and deeper head, and larger eyes, and the caudal peduncle is more slender. Aerial photo of Borax Lake in Eastern Oregon The Borax Lake chub eats a variety of foods, including midge larvae, diatoms, copepods, ostracods, and terrestrial insects. Its preferred mode of feeding is to root around in the bottom, but it will go after floating material or feed from the surface if necessary. This species is the sole fish inhabiting the Borax Lake waters.
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Fernanda D'Agostino's Urban Hydrology was installed along three blocks of Southwest Sixth Avenue (between Hall and Mill) on the Portland Transit Mall, adjacent to the Portland State University campus, in 2009. It features a series of twelve carved granite stones, each measuring x x , bioswales, and native plants. The sculptures are based on scanning electron microscope photographs of diatoms used for determining water quality in urban waterways. The $84,000 project was commissioned by TriMet; other partners included the Environmental Studies Department at Portland State University and the city's Water Bureau.
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Biofilms and microbial mats are omnipresent at El Tatio, including Calothrix, Leptolyngbya, Lyngbya and Phormidium cyanobacteria, which form mats within the hot springs covering the solid surfaces, including oncoids and the sinter. In other places, the aforementioned three genera form stromatolithic structures. Chroococcidiopsis is another cyanobacterium that can be found in hot waters of El Tatio, and non-cyanobacteria bacteria have also been found in the mats and sinter. There is a thermal gradation of microorganisms, with the hottest waters supporting Chloroflexus green bacteria and hyperthermophiles, cyanobacteria at less than water temperature and diatoms at even lower temperatures.
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The larvae drift with the plankton and pass through several developmental stages before settling on the seabed and anchoring themselves with a stalk. After metamorphosis the stalk remains intact at first but later breaks and the juvenile feather star can move around independently. The variable bushy feather star is sometimes sold for display in reef aquaria, however it is not easy to meet its food requirements and most aquarium specimens sooner or later die of starvation. It can be fed with brine shrimp larvae, copepods and diatoms after turning off the particulate filter on the tank.
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Among the traits that are thought to characterize r-selection are high fecundity, small body size, early maturity onset, short generation time, and the ability to disperse offspring widely. Organisms whose life history is subject to r-selection are often referred to as r-strategists or r-selected. Organisms that exhibit r-selected traits can range from bacteria and diatoms, to insects and grasses, to various semelparous cephalopods and small mammals, particularly rodents. As with K-selection, below, the r/K paradigm (Differential K theory) has controversially been associated with human behavior and separately evolved populations.
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In the summer, blooms are seen more regularly and are typically dominated by diatoms and cyanobacteria. These regular summer blooms may be caused by variations in the PDO. Summer blooms have been observed in these waters as long as research vessels have been frequenting them. All of these blooms have been seen in the eastern part of the NSPG with none reported west of 160° W. Hypotheses to explain this phenomenon are that the gyre is characterized by low phosphate, but that the bloom region of the eastern NPSG has considerably higher phosphate concentrations than the western.
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The use of these calibration lakes is necessary to identify dramatic differences in a newly collected core compared to normal variations which would be depicted in the calibration lakes. Through the use of sediment cores as a technique, paleolimnologists are able to use other proxies (such as pollen, charcoal, diatoms, chironomids, and other organic matter) in order to reconstruct the past climatic conditions of an area. Lake sediment cores in particular offer a more comprehensive analysis of an area because of the continual accumulation of sediment as well as other organic matter like pollen and charcoal.
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According to Eggermont and Heiri there is indirect impact of temperature on different physic chemical aspects of water resulted into determination of their distribution and abundance. There is also a strong relationship between the chironomids abundance, emergence and distribution with the mean temperature of the air and water. According to a research conducted in high altitude lake Lej da la Tscheppain Switzerland, seasonal temperature reconstruction can be done with the help of independent chironomids and diatoms. Any change in the assemblage of chironomids reflects change in the temperature and duration of ice cover of that specific water body due to climate change.
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In terms of number of species, dinoflagellates are one of the largest groups of marine eukaryotes, although this group is substantially smaller than diatoms. Some species are endosymbionts of marine animals and play an important part in the biology of coral reefs. Other dinoflagellates are unpigmented predators on other protozoa, and a few forms are parasitic (for example, Oodinium and Pfiesteria). Some dinoflagellates produce resting stages, called dinoflagellate cysts or dinocysts, as part of their lifecycles, and is known from 84 of the 350 described freshwater species, and from a little more than 10% of the known marine species.
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Calcareous oozes are predominantly composed of calcium shells found in phytoplankton such as coccolithophores and zooplankton like the foraminiferans. These calcareous oozes are never found deeper than about 4,000 to 5,000 meters because at further depths the calcium dissolves."The Bottom of the Ocean," Marine Science Similarly, Siliceous oozes are dominated by the siliceous shells of phytoplankton like diatoms and zooplankton such as radiolarians. Depending on the productivity of these planktonic organisms, the shell material that collects when these organisms die may build up at a rate anywhere from 1mm to 1 cm every 1000 years.
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The sedimentary succession was studied through isotope analysis, diatoms, organic geochemistry, and tephrochronology. These lines of evidence suggest that there were large changes around Lake Texcoco in terms of the balance between aquatic and terrestrial plants, C3 and C4 plants, saline, alkaline and freshwater conditions, volcanic activity, reworking of lake sediments, and input from the drainage basin throughout the late Pleistocene and late Holocene. These changes also had large effects on the prehistoric human populations living around the lake at this time.Lamb, Angela L., Silvia Gonzalez, David Huddart, Sarah E. Metcalfe, Christopher H. Vane, and Alistair W.G. Pike. 2009.
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Iron fertilization projects like the SERIES iron-enrichment experiments have introduced iron into ocean basins to test if this increases the rate of carbon dioxide uptake by diatoms and ultimately sinking it to the deep ocean. Iron is a limiting nutrient for diatom photosynthesis in high- nutrient, low-chlorophyll areas of the ocean, thus Increasing the amount of available iron can lead to a subsequent increase in photosynthesis, sometimes resulting in a diatom bloom. This increase removes more carbon dioxide from the atmosphere. Although more carbon dioxide is being taken up, the carbon sequestration rate in deep sea sediments is generally low.
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Other conserved regions in the genomes which are frequently used as marker genes are ribulose-1-5-bisphosphate carboxylase (rbcL), cytochrome oxidase I (cox1, COI), ITS and 28S. It has been shown repeatedly that the molecular data gained by diatom eDNA metabarcoding quite faithfully reflect the morphology-based biotic diatom indices and therefore provide a similar assessment of ecosystem status. In the meantime, diatoms are routinely used for the assessment of ecological quality in other freshwater ecosystems. Together with aquatic invertebrates they are considered as the best indicators of disturbance related to physical, chemical or biological conditions of watercourses.
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Additionally, primer bias is often found to be a major source of variation in barcoding and PCR primers efficiency can differ between diatoms species, i.e. some primers lead to a preferential amplification of one taxon over another. The inference of abundance from metabarcoding data is considered as one of the most difficult issues in environmental use. The number of generated sequences by HTS does not directly correspond to the number of specimen or biomass and that different species can produce different amount of reads, (for example, due to differences in the chloroplast size with the rbcL marker).
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Pulsed laser irradiation is commonly used against diatoms. Plasma pulse technology is effective against zebra mussels and works by stunning or killing the organisms with microsecond duration energizing of the water with high voltage electricity. There are several companies that offer alternatives to paint- based antifouling, using ultrasonic transducers mounted in or around the hull of small to medium-sized boats. Research has shown these systems can help reduce fouling, by initiating bursts of ultrasonic waves through the hull medium to the surrounding water, killing or denaturing the algae and other micro-organisms that form the beginning of the fouling sequence.
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The moist sand above the water mark is excellent M. lignano habitat Sampling of moist sand with M. lignano Macrostomum lignano lives interstitially in sandy habitats, at the intertidal or upper-intertidal zone, usually in the upper 5–10 mm. It only needs a little humidity in the sand to survive, but it can also be found underwater during high tide. It favours protected areas with no or very low wave exposure like tidal lagoons. M. lignano feeds primarily on diatoms, but it has been observed to eat small invertebrates and, occasionally, eggs (even conspecific, and sometimes its own).
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Lake Van viewed from space shuttle Challenger during flight STS-41-G The only fish known to live in the brackish water of Lake Van is Chalcalburnus tarichi or Pearl Mullet (), a Cyprinid fish related to chub and dace, which is caught during the spring floods. In May and June, these fish migrate from the lake to less alkaline water, spawning either near the mouths of the rivers feeding the lake or in the rivers themselves. After spawning season it returns to the lake. 103 species of phytoplankton have been recorded in the lake including cyanobacteria, flagellates, diatoms, green algae, and brown algae.
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Individual cells may regulate buoyancy via an ionic pump. Some pennate diatoms are capable of a type of locomotion called "gliding", which allows them to move across surfaces via adhesive mucilage secreted through the raphe (an elongated slit in the valve face). In order for a diatom cell to glide, it must have a solid substrate for the mucilage to adhere to. Cells are solitary or united into colonies of various kinds, which may be linked by siliceous structures; mucilage pads, stalks or tubes; amorphous masses of mucilage; or by threads of chitin (polysaccharide), which are secreted through strutted processes of the cell.
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Diatoms are a widespread group and can be found in the oceans, in fresh water, in soils, and on damp surfaces. They are one of the dominant components of phytoplankton in nutrient-rich coastal waters and during oceanic spring blooms, since they can divide more rapidly than other groups of phytoplankton. Most live pelagically in open water, although some live as surface films at the water-sediment interface (benthic), or even under damp atmospheric conditions. They are especially important in oceans, where they contribute an estimated 45% of the total oceanic primary production of organic material.
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Since vertical mixing is increasing, and light levels are falling as winter approaches, these blooms are smaller and shorter-lived than their spring equivalents. In the open ocean, the diatom (spring) bloom is typically ended by a shortage of silicon. Unlike other minerals, the requirement for silicon is unique to diatoms and it is not regenerated in the plankton ecosystem as efficiently as, for instance, nitrogen or phosphorus nutrients. This can be seen in maps of surface nutrient concentrations – as nutrients decline along gradients, silicon is usually the first to be exhausted (followed normally by nitrogen then phosphorus).
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The sequences compared in this study were used to create a diverse background in order to identify residues that differentiate function in the silica deposition process. Additionally, the same study found that a number of the regions were conserved within species, likely the base structure of silica transport. These silica transport proteins are unique to diatoms, with no homologs found in other species, such as sponges or rice. The divergence of these silica transport genes is also indicative of the structure of the protein evolving from two repeated units composed of five membrane bound segments, which indicates either gene duplication or dimerization.
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Reproduction among these organisms is asexual by binary fission, during which the diatom divides into two parts, producing two "new" diatoms with identical genes. Each new organism receives one of the two frustules – one larger, the other smaller – possessed by the parent, which is now called the epitheca; and is used to construct a second, smaller frustule, the hypotheca. The diatom that received the larger frustule becomes the same size as its parent, but the diatom that received the smaller frustule remains smaller than its parent. This causes the average cell size of this diatom population to decrease.
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24-Norcholestane, a steroid derivative, is used as a biomarker to constrain the source age of sediments and petroleum through the ratio between 24-norcholestane and 27-norcholestane (24-norcholestane ratio, NCR), especially when used with other age diagnostic biomarkers, like oleanane. While the origins of this compound are still unknown, it is thought that they are derived from diatoms due to their identification in diatom rich sediments and environments. In addition, it was found that 24-norcholestane levels increased in correlation with diatom evolution. Another possible source of 24-norcholestane is from dinoflagellates, albeit to a much lower extent.
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English makers early took up this improvement, due to the obsession with resolving test objects such as diatoms and Nobert ruled gratings. By the late 1840s, English makers such as Ross, Powell and Smith; all could supply highly corrected condensers on their best stands, with proper centring and focus. It is erroneously stated that these developments were purely empirical - no-one can design a good achromatic, spherically corrected condenser relying only on empirics. On the Continent, in Germany, the corrected condenser was not considered either useful or essential, mainly due to a misunderstanding of the basic optical principles involved.
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Benthic diatoms have been used by the European Union's Water Framework Directive (WFD) to establish ecological quality ratios that determined the ecological status of lakes in the UK. Beginning research is being made on benthic assemblages to see if they can be used as indicators of healthy aquatic ecosystems. Benthic assemblages in urbanized coastal regions are not functionally equivalent to benthic assemblages in untouched regions. Ecologists are attempting to understand the relationship between heterogeneity and maintaining biodiversity in aquatic ecosystems. Benthic algae has been used as an inherently good subject for studying short term changes and community responses to heterogeneous conditions in streams.
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At Laguna Vilama and other lakes birds like Andean geese, Darwin's rhea, ducks and flamingos can be observed, mammals in the region include chinchillas, vicuñas and vizcachas. Microbial mats have been observed at Laguna Vilama. Diatoms can be found in the lake waters, and the diatom species Staurophora vilamae, the bacterial species Halomonas vilamensis and Halopeptonella vilamensis were first discovered in Laguna Vilama. The environment around these lakes has remained stable over the last three millennia, but since the 1970s a trend towards a drier climate has been observed, accompanied by a shrinkage of the lake.
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He worked in California as a botanist at Los Angeles and Berkeley University, devising a new system of classification of the diatoms based on the internal structures of the specimens in his Black Sea collection. In 1902, he returned to Russia to become curator of zoology at Kazan University, Tatarstan; he became a lecturer there in 1904, and started to develop his ideas on the symbiotic origins of complex cells. In 1914 he was prosecuted for raping 26 girls, including one who became one of his students aged six. He was dismissed from the university, and escaped to France.
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In terms of numbers, the most important groups of phytoplankton include the diatoms, cyanobacteria and dinoflagellates, although many other groups of algae are represented. One group, the coccolithophorids, is responsible (in part) for the release of significant amounts of dimethyl sulfide (DMS) into the atmosphere. DMS is oxidized to form sulfate which, in areas where ambient aerosol particle concentrations are low, can contribute to the population of cloud condensation nuclei, mostly leading to increased cloud cover and cloud albedo according to the so-called CLAW Hypothesis. Different types of phytoplankton support different trophic levels within varying ecosystems.
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Blastocystis is a genus of single-celled heterokont parasites belonging to a group of organisms that are known as the Stramenopiles (also called Heterokonts) that includes algae, diatoms, and water molds. Blastocystis consists of several species, living in the gastrointestinal tracts of species as diverse as humans, farm animals, birds, rodents, reptiles, amphibians, fish, and cockroaches. Blastocystis exhibits low host specificity, and many different species of Blastocystis can infect humans, and by current convention, any of these species would be identified as Blastocystis hominis. Blastocystis is one of the most common human parasites in the world and has a global distribution.
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In the south-eastern part of the lake, phytoplanktons are dominated by various species of cyanobacterias, some of which are nitrogen-binding and potentially poisonous, and exceptionally other nutrient-demanding algae and dinoflagellates. Zooplankton are only found in small quantities. Variations in quantity appears between the southern and northern parts of the lake, with more an abundant presence of green algae in the northern end where dinoflagellates are substituted also by diatoms. Striking when it comes to aquatic plants is the abundance of spiked water-milfoil and rigid hornswort in the north-western part of the lake.
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Incredibly erudite in everything > concerning the island. Firm Venezelist [supporter of Eleftherios Venizelos], > and possessor of the dryest and most fastidious style of exposition ever > seen. Thumbnail portrait of bearded man in boots and cape, with massive bug- > hunting apparatus on his back stalking across country to a delectable pond > where his microscopic world of algae and diatoms (the only real world for > him) lies waiting to be explored. Theodore is always being arrested as a > foreign agent because of the golden beard, strong English accent in Greek, > and mysterious array of vessels and swabs and tubes dangling about his > person.
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Waters from the modern Pacific and Southern ocean, typically observe an increase in Si/N ratio at intermediate depth, which results in an increase in opal export (~ increase in opal production). In the Southern Ocean and North Pacific, this relationship between opal export and Si/N ratio switches from linear to exponential for Si/N ratios greater than 2. This gradual increase in the importance of silicate (Si) relative to nitrogen (N) has tremendous consequences for the ocean biological production. The change in nutrient ratios contributes to select diatoms as main producers, compared to other (e.g.
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Pawsonia saxicola is a suspension feeder, consuming diatoms and single-cell algae and also zooplankton, such as copepods, ostracods, protozoans, nematodes, jellyfish and larvae, as well as drifting organic particles. The food is gathered by the feeding tentacles which each in turn shrinks and bends and is inserted into the mouth; the two ventral tentacles are short and forked, and are used at the mouth to push particles inside. Although in some related species the short tentacles co-ordinate their activities with the longer tentacles, this is not the case in P. saxicola where they seem to act independently.
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Phytoplankton blooms are dominated by diatoms and grazed by copepods in the open ocean, and by krill closer to the continent. Diatom production continues through the summer, and populations of krill are sustained, bringing large numbers of cetaceans, cephalopods, seals, birds, and fish to the area. Phytoplankton blooms are believed to be limited by irradiance in the austral (southern hemisphere) spring, and by biologically available iron in the summer. Much of the biology in the area occurs along the major fronts of the current, the Subtropical, Subantarctic, and the Antarctic Polar fronts, these are areas associated with well defined temperature changes.
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These later develop into veliger larvae which settle on the seabed and undergo metamorphosis into juveniles that are sometimes (for example in the case of oysters) known as "spat". In some species, such as those in the genus Lasaea, females draw water containing sperm in through their inhalant siphons and fertilization takes place inside the female. These species then brood the young inside their mantle cavity, eventually releasing them into the water column as veliger larvae or as crawl- away juveniles. Most of the bivalve larvae that hatch from eggs in the water column feed on diatoms or other phytoplankton.
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In 1947, she formed and chaired the academy's Department of Limnology. She continued to work there for many years and was regarded as a talented and outstanding scientific administrator, in addition to her other scientific contributions. Patrick's work on the Great Salt Lake in the 1930s used the history of diatoms in the sediments of the lake to prove the lake was once a freshwater body of water, and established some solid clues as to what caused the shift to saltwater. In 1945 she invented the diatometer, a device to take better samples for studying diversity in water ecology.
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CD "What Would This Record Have Sounded Like of John Cale had had Some Setback and Cinzia La Fauci and Alberto Scotti had Taken His Place?" 2000 Compilation of Iggy Pop covers by various artists including: Perkis, Etoile Filante, Solex, Taniguchi Masaaki, Ectogram, Steven Bryant, Jonathan LaMaster/Roger Miller, Frank Chickens, Crowded Air, Oxbox, Allun, God is my Co-pilot, Dean Roberst, Massey Fergusson Ensemble, The Pornography, Culo Negro and Mutable. A co-production of Snowdonia (Messina, Italy) and Club Lunatica (Tokyo). CD "Diatoms" 1999 Duo improvisations with Lelio Giannetto, bass. Recorded in Palermo, Sicily 12/5/1998.
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Cyanobacteria remained principal primary producers throughout the Proterozoic Eon (2500–543 Ma), in part because the redox structure of the oceans favored photoautotrophs capable of nitrogen fixation. Green algae joined blue-greens as major primary producers on continental shelves near the end of the Proterozoic, but only with the Mesozoic (251–65 Ma) radiations of dinoflagellates, coccolithophorids, and diatoms did primary production in marine shelf waters take modern form. Cyanobacteria remain critical to marine ecosystems as primary producers in oceanic gyres, as agents of biological nitrogen fixation, and, in modified form, as the plastids of marine algae.
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Flora of North America, Baileya Harvey & A. Gray ex Torrey in W. H. Emory Desert marigolds typically have their main bloom in the spring, extending through July. Summer thunderstorms may enable a second bloom in October and even into November.Jepson Manual Treatment Baileya species are used as food plants by the larvae of some Lepidoptera species including Schinia miniana (which feeds exclusively on the genus) and Schinia pallicincta (which feeds exclusively on B. pauciradiata). The genus is named after US microscopist and West Point professor Jacob Whitman Bailey (1811–1857), known for his studies of diatoms .
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The lake probably supported a substantial ecosystem, and a number of diatoms developed there. In Death Valley, lakes existed during different times in the geological past. After some poorly defined lake stages during the Miocene, Pliocene and early Pleistocene, the first large lake stage occurred about 185,000–128,000 years ago during the Tahoe glacial stage and formed the Blackwelder shorelines. This lake was the largest known Lake Manly; theories that the lake merged with Lake Mojave farther south or even overflowed into the Colorado River close to Ludlow and across several other basins are, however, questionable.
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It was considered that the most parsimonious explanation for its presence was that its low abundance meant it had been previously overlooked as a member of the Lake Rukwa ichthyofauna rather than deliberate introduction. Its natural habitats are rivers, freshwater lakes, and inland deltas over rock substrates. It feeds on aufwuchs as well as a variety of food collected from rocky river or lake beds including insects, ostracods, diatoms and worms. It is threatened by habitat loss caused by increased turbidity of the water due to deforestation increasing sediment runoff in the catchments of the lake's tributary rivers.
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The rise in agriculture of the past 400 years has increased the exposure rocks and soils, which has resulted in increased rates of silicate weathering. In turn, the leaching of amorphous silica stocks from soils has also increased, delivering higher concentrations of dissolved silica in rivers. Conversely, increased damming has led to a reduction in silica supply to the ocean due to uptake by freshwater diatoms behind dams. The dominance of non-siliceous phytoplankton due to anthropogenic nitrogen and phosphorus loading and enhanced silica dissolution in warmer waters has the potential to limit silicon ocean sediment export in the future.
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It will spend over half of its time on land, but will purposely submerge to wet its gills but can sustain itself on land for up to ~70 hours. They enjoy hiding in small crevices within rock, but will emerge at night when there is less danger of predation. This opportunistic predator's diet consists of green algae, red algae, brown seaweed, diatoms, worms, mussels, small decaying organisms, limpets, snails, flies, hermit crabs, seaweed, isopods, and sometimes even each other when the lesser crab has just finished molting. They have preference to small mussels over larger mussels over seaweed.
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Pelomyxa have multiple nuclei, which can number from two to several thousand in rare cases. A moving cell is cylindrical in shape, with a single hemispherical pseudopod at the front and a semipermanent projection called a uroid at the back, which is covered in tiny non-motile flagella. They consume a wide variety of food, and have many vacuoles containing both food, such as diatoms, and debris such as sand. Pelomyxa are reliant on symbiotic bacteria that function similarly to the mitochondrion of aerobic creature, enabling the otherwise anaerobic species to live in more aerobic environments.
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Chiton glaucus show clear daily patterns of activity; they remain hidden during the day to escape visual predators and then during the night they travel to the tops of the rock to feed on the algae that has grown there since the previous night. According to research done by Robert Creese who analysed the contents in the gut of C. glaucus it was found that the main component of its diet is that of coralline algae. Other research suggests a broader range of organisms within its diet including encrusting organisms (sponges, bryozans etc.) and on diatoms and algae in a grazing type method.
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Poecilochaetus serpens forms a U–shaped burrow in sand, the tube being lined by particles of clay or mud cemented with mucus; digging is performed by the head using the parapodial cirri attached to the first segment and associated long bristles. A water current is drawn through the tube by undulations of the body and fan- like movements of the parapodia and bristles. The worm can turn around in its tube, and then the current direction is reversed. The worm probably feeds on plankton and organic particles removed from the water current, and diatoms have been found in its gut.
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Depending upon the composition and timing of delivery, iron infusions could preferentially favor certain species and alter surface ecosystems to unknown effect. Population explosions of jellyfish, which disturb the food chain impacting whale populations or fisheries, are unlikely as iron fertilization experiments are conducted in high-nutrient, low-chlorophyll waters that favor the growth of larger diatoms over small flagellates. This has been shown to lead to increased abundance of fish and whales over jellyfish. A 2010 study showed that iron enrichment stimulates toxic diatom production in high-nitrate, low-chlorophyll areas which, the authors argue, raises "serious concerns over the net benefit and sustainability of large-scale iron fertilizations".
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This clam is a filter feeder and consumes microscopic algae such as dinoflagellates, diatoms, and cyanobacteria. Some dinoflagellates produce neurotoxins, such as saxitoxin and its derivates, that bioaccumulate in the clams and other bivalve mollusks and can cause paralytic shellfish poisoning (PSP) when the clams are eaten. Despite this fact, the clam was eaten by Native Americans and is still used as a food for humans. According to a 1996 report from the Marine Advisory Program at the University of Alaska, the United States Food and Drug Administration (FDA) considers seafood unsafe if it contains more than 80 μg of PSP-causing toxins per 100 g of tissue of the seafood.
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He was particularly interested in a unicellular group of protists called diatoms, but he also studied, and named, many species of radiolaria, foraminifera and dinoflagellates. These researches had an important bearing on some of the infusorial earths used for polishing and other economic purposes; they added, moreover, largely to our knowledge of the microorganisms of certain geological formations, especially of the chalk, and of the marine and freshwater accumulations. Until Ehrenberg took up the study it was not known that considerable masses of rock were composed of minute forms of animals or plants. He also demonstrated that the phosphorescence of the sea was due to organisms.
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Lancelets are inactive filter feeders, spending most of the time half-buried in sand with only their frontal part protruding. They eat a wide variety of small planktonic organisms, such as bacteria, fungi, diatoms, dinoflagellates and zooplankton, and they will also take detritus. Little is known about the diet of the lancelet larvae in the wild, but captive larvae of several species can be maintained on a diet of phytoplankton, although this apparently is not optimal for Asymmetron lucayanum. Lancelets have oral cirri, thin tentacle-like strands that hang in front of the mouth and act as sensory devices and as a filter for the water passing into the body.
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One species, Amoebophrya ceratii, has lost its mitochondrial genome completely, yet still has functional mitochondria. The genes on the dinoflagellate genomes have undergone a number of reorganisations, including massive genome amplification and recombination which have resulted in multiple copies of each gene and gene fragments linked in numerous combinations. Loss of the standard stop codons, trans-splicing of mRNAs for the mRNA of cox3, and extensive RNA editing recoding of most genes has occurred. The reasons for this transformation are unknown. In a small group of dinoflagellates, called ‘dinotoms’ (Durinskia and Kryptoperidinium), the endosymbionts (diatoms) still have mitochondria, making them the only organisms with two evolutionarily distinct mitochondria.
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With respect to scallop culture, two categories of toxins have been reported: Paralytic shellfish poisoning (PSP) and amnesic shellfish poisoning (ASP). PSP has been reported for a number of years in Placopecten magellanicus in the Northwest Atlantic and so must be considered in culture operations, particularly as P. magellanicus is reported as being a slow detoxifyer of the toxin. ASP is a neurotoxin produced by some marine diatoms and has also been reported in scallops from the Northwest Atlantic (Bird & Wright, 1989). Diarrehetic shellfish poisons (DSP) have also been identified as a potential problem, however, they have not yet been reported in scallop culture.
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These adaptations to life under the sediment provide protection for the worm from desiccation and predation while providing a plentiful supply of food and oxygen. At low tide, when the sediment in which the lugworm is living is no longer covered by water, aerial respiration takes place.The Effects of Oxygen Concentration and Anoxia on Respiration of Abarenicola pacifica and Lumbrineris zonata (Polychaeta) When feeding, A. pacifica everts its oesophagus (which then resembles a mushroom) and engulfs a "mouthful" of sand before restoring the oesophagus to its rightful position. Organic detritus and organisms such as nematodes, diatoms, bacteria and microphytes Abarenicola pacifica are ingested with the sand and digested in the gut.
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Odontaster validus in Tokyo Sea Life Park Odontaster validus is an omnivorous scavenger and consumes anything it finds including carrion, detritus, the faeces of seals, red algae, bivalve shells, sponges, hydroids, other sea star, sea urchins, isopods, bryozoans, amphipods, crustacean larvae, ostracods, shrimps and diatoms. They have been observed aggregating on banks of mussels that have been exposed and damaged and on injured sea star, Acodontaster conspicuus. In turn, they are preyed upon by sea anemones and other species of sea star. It is an ecologically important species because of its consumption of benthic larvae and the control it exerts on the sea star Acodontaster conspicuus and the nudibranch Doris spp.
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Some species which go through the metamorphosis inside the egg and hatch to small frogs never develop gills; instead there are specialised areas of skin that take care of respiration. Tadpoles also lack true teeth, but the jaws in most species usually have two elongate, parallel rows of small keratinized structures called keradonts in the upper jaw while the lower jaw has three rows of keradonts, surrounded by a horny beak, but the number of rows can be lower (sometimes zero), or much higher. Tadpoles feed on algae, including diatoms filtered from the water through the gills. Some species are carnivorous at the tadpole stage, eating insects, smaller tadpoles, and fish.
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Some species prefer certain sizes and types of rock particles; other species are preferential towards certain biological materials. Certain species of foraminifera are known to have preferentially agglutinated coccoliths to form their tests; others preferentially utilise echinoderm plates, diatoms, or even other foraminiferans' tests. The foraminifera Spiculosiphon preferentially agglutinates silica sponge spicules using an organic cement; it shows strong selectivity also towards shape, utilising elongated spicules on its "stalk" and shortened ones on its "bulb". It is thought to use the spicules as both a means of elevating itself off the seabed as well as to lengthen the reach of its pseudopodia to capture prey.
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They are composed of upper and lower valves – epitheca and hypotheca – each consisting of a valve and a girdle band that can easily slide underneath each other and expand to increase cell content over the diatoms progression. The cytoplasm of the centric diatom is located along the inner surface of the shell and provides a hollow lining around the large vacuole located in the center of the cell. This large, central vacuole is filled by a fluid known as "cell sap" which is similar to seawater but varies with specific ion content. The cytoplasmic layer is home to several organelles, like the chloroplasts and mitochondria.
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Ultimately, diatom cells in these resting populations re-enter the upper mixed layer when vertical mixing entrains them. In most circumstances, this mixing also replenishes nutrients in the upper mixed layer, setting the scene for the next round of diatom blooms. In the open ocean (away from areas of continuous upwelling), this cycle of bloom, bust, then return to pre-bloom conditions typically occurs over an annual cycle, with diatoms only being prevalent during the spring and early summer. In some locations, however, an autumn bloom may occur, caused by the breakdown of summer stratification and the entrainment of nutrients while light levels are still sufficient for growth.
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The silica deposition that takes place from the membrane bound vesicle in diatoms has been hypothesized to be a result of the activity of silaffins and long chain polyamines. This Silica Deposition Vesicle (SDV) has been characterized as an acidic compartment fused with Golgi-derived vesicles. These two protein structures have been shown to create sheets of patterned silica in-vivo with irregular pores on the scale of diatom frustules. One hypothesis as to how these proteins work to create complex structure is that residues are conserved within the SDV's, which is unfortunately difficult to identify or observe due to the limited number of diverse sequences available.
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The site is apparently geologically unique in the Hawaiian Islands, comprising a sinkhole paleolake within a large cave system formed in eolianite limestone. The paleolake contains nearly 10,000 years of sedimentary record; since the discovery of Makauwahi as a fossil site, excavations have found pollen, seeds, diatoms, invertebrate shells, and Polynesian artifacts, as well as thousands of bird and fish bones.Kido (2008). The findings document not only the conditions before human colonization of the Hawaiian islands, but also the millennium of human occupation with the drastic ecological changes that occurred since first Polynesians, and later Europeans and Asians, arrived in the islands along with a suite of invasive alien species.
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Paralytic shellfish poisoning (PSP) is one of the four recognized syndromes of shellfish poisoning, which share some common features and are primarily associated with bivalve mollusks (such as mussels, clams, oysters and scallops). These shellfish are filter feeders and accumulate neurotoxins, chiefly saxitoxin, produced by microscopic algae, such as dinoflagellates, diatoms, and cyanobacteria. Dinoflagellates of the genus Alexandrium are the most numerous and widespread saxitoxin producers and are responsible for PSP blooms in subarctic, temperate, and tropical locations. The majority of toxic blooms have been caused by the morphospecies Alexandrium catenella, Alexandrium tamarense, Gonyaulax catenella and Alexandrium fundyense, which together comprise the A. tamarense species complex.
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Food supplies, such as algae the tadpoles eat, also affect the sexual maturity of the species. Reportedly, the "amount of protein in different algae, can affect size at and time to metamorphosis" and "these food effects may be mediated through diet-induced changes in thyroid function", which means the food the tadpoles ingest dictates the changes in the thyroid gland's production of certain proteins. Tadpoles most commonly feed on algae, diatoms, and detritus. As the species grows older, it changes its diet to animal tissue which must be swallowed whole because the frog's jaw is structured on a hinge joint that does not allow for sideways movement as in humans.
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Many models suggest that overlying sediment mineralized before the underlying organism decayed, causing the un-mineralized underlying sediment to fill the void after decay. One mode of early sediment mineralization, which accounts for the occurrence of this preservational mode into the Cambrian and its increasing scarcity thereafter, is silicification: this links the preservation of the fossils to the higher silica content of oceans before sponges, diatoms and other silica sinks became widespread. This hypothesis struggles to account for a number of observations, particularly in the Flinders and White Sea deposits; it is therefore difficult to argue that it formed a necessary component of Ediacara type preservation.
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Vanadium bromoperoxidases have been found in bacteria, fungi, marine macroalgae (seaweeds), and marine microalgea (diatoms) which produce brominated organic compounds. It has not been definitively identified as the bromoperoxidase of higher eukaryotes, such as murex snails, which have a very stable and specific bromoperoxidase, but perhaps not a vanadium dependent one. While the purpose of the bromoperoxidase is still unknown, the leading theories include that it’s a way of regulating hydrogen peroxide produced by photosynthisis and/or as a self-defense mechanism by producing hypobromic acid which prevents the growth of bacteria. The enzymes catalyse the oxidation of bromide (0.0067% of sea water) by hydrogen peroxide.
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Progradungula otwayensis (Gradungulidae) holding a snare made from silk spun from its cribellum Cribellum literally means "little sieve", and in biology the term generally applies to anatomical structures in the form of tiny perforated plates. In certain groups of diatoms it refers to microscopically punctured regions of the frustule, or outer layer. In certain groups of spider species, so-called cribellate spiders, the cribellum is a silk spinning organ. Unlike the usual spinnerets of spiders, the cribellum consists of one or more plates covered in thousands of tiny spigots, tiny holes that hardly project from the surface, in contrast to the elongated spigots that project from spinnerets.
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Cassie Cooper has garnered several awards and titles for her accomplishments, including an honorary research associateship by the Botany Department at University of Auckland and the Botany Division of DSIR, and an honorary life membership of the New Zealand Limnological Society and the New Zealand Marine Science Society. In the 1997 Queen's Birthday Honours, she was appointed a Member of the New Zealand Order of Merit, for services to marine biology. She was described as New Zealand's "leading expert" on diatoms. Cassie Cooper was a founding member of the Australasian Society for Phycology and Aquatic Botany, the International Society of Diatomists, and the Asian Pacific Phycological Association.
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LSi can either be accumulated "directly" in marine sediments as clastic particles or be transferred into dissolved silica (DSi) in the water column. Within living marine systems, DSi is the most important form of silica Forms of DSi, such as silicic acid (Si(OH)4), are utilized by silicoflagellates and radiolarians to create their mineral skeletons, and by diatoms to develop their frustules (external shells). These structures are vitally important, as they can protect, amplify light for photosynthesis, and even help keep these organisms afloat in the water column. DSi more readily forms from biogenic silica (BSi) than from LSi, as the latter is less soluble in water.
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The fact that carbon is used instead of silicon may be evidence that silicon is poorly suited for biochemistry on Earth-like planets. Reasons for which may be that silicon is less versatile than carbon in forming compounds, that the compounds formed by silicon are unstable, and that it blocks the flow of heat. Even so, biogenic silica is used by some Earth life, such as the silicate skeletal structure of diatoms. According to the clay hypothesis of A. G. Cairns-Smith, silicate minerals in water played a crucial role in abiogenesis: they replicated their crystal structures, interacted with carbon compounds, and were the precursors of carbon-based life.
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Esther went to the 19th International Geological Congress in Algiers in 1952, where she met her soon to be husband Donald Holm who was a geologist. During her stay in Algiers, Esther taught Economic Geography to a variety of people. Esther's contribution to the study of diatoms and Radiolaria was included in the Treatise on Ecology and Paleoecology in 1957. Always finding things to contribute to, she transferred from Washington to Flagstaff, AZ in 1965 to the Branch of Astrology contributed to the program of studies of the lunar equatorial zone Finally retiring in 1971, Esther received the highest award of the Interior Department, the Distinguished Service Medal.
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They depend on the shallow shelf for spawning as well as for much of their diet which primarily consists of diatoms. Natural threats from flash floods to earthquakes have been known to disrupt this fragile ecosystem, but in the 1960s and 1970s, the major threat was groundwater depletion due to agricultural irrigation. Research indicates that the annual population fluctuation is in response to the amount of algae on the shallow shelf, which is dependent on incoming solar radiation and nutrient levels. Nutrient availability may peak when the cave is used by barn owls as a roosting or nesting site, as their nutrient-rich pellets fall into the water.
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They are relatively large amphipods, with adults of the various species ranging from in head-and-body length. They are typically white, yellowish, orange, pinkish, red or purplish, and some have quite striking colour patterns. Some have a spiny crest along their mid-back and spines on their sides, which may serve as a protection against fish or serve as a "disruptive shape" (similar to disruptive colouration) that camouflages the amphipod. Most species are predators or scavengers that feed on bethic invertebrates (such as small crustaceans, brittle stars, sea cucumbers, sponges, cnidarians and polychaetes), or suspension feeders that take plankton (such as diatoms, radiolarians and foraminifers).
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Pseudo-nitzschia is a marine planktonic diatom genus that accounts for 4.4% of pennate diatoms found worldwide. Some species are capable of producing the neurotoxin domoic acid (DA), which is responsible for the neurological disorder in humans known as amnesic shellfish poisoning (ASP). Currently, 57 species are known, 27 of which have been shown to produced DA. It was originally hypothesized that only dinoflagellates could produce harmful algal toxins, but a deadly bloom of Pseudo-nitzschia occurred in 1987 in the bays of Prince Edward Island, Canada, and led to an outbreak of ASP. Over 100 people were affected by this outbreak after consuming contaminated mussels; three people died.
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The earliest reported observations of pollen under a microscope are likely to have been in the 1640s by the English botanist Nehemiah Grew, who described pollen and the stamen, and concluded that pollen is required for sexual reproduction in flowering plants. By the late 1870s, as optical microscopes improved and the principles of stratigraphy were worked out, Robert Kidston and P. Reinsch were able to examine the presence of fossil spores in the Devonian and Carboniferous coal seams and make comparisons between the living spores and the ancient fossil spores. Early investigators include Christian Gottfried Ehrenberg (radiolarians, diatoms and dinoflagellate cysts), Gideon Mantell (desmids) and Henry Hopley White (dinoflagellate cysts).
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Fusulinid (Triticites) from the Plattsmouth Chert, Red Oak, Iowa (Permian). Micropaleontology can be roughly divided into four areas of study on the basis of microfossil composition: (a) calcareous, as in coccoliths and foraminifera, (b) phosphatic, as in the study of some vertebrates, (c) siliceous, as in diatoms and radiolaria, or (d) organic, as in the pollen and spores studied in palynology. This division reflects differences in the mineralogical and chemical composition of microfossil remains (and therefore in the methods of fossil recovery) rather than any strict taxonomic or ecological distinctions. Most researchers in this field, known as micropaleontologists, are typically specialists in one or more taxonomic groups.
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Schloss has participated in nine expeditions to Antarctica (ship-based and on Argentinean stations), spending around 17 months in the sixth continent. Her greatest impact has been in research on the interactions the adaptation and effects of plankton to ocean climate change. Her work has modelled physical-biological interactions during bloom dynamics in coastal Antarctica, in particular the equilibrium between warming, glacier melt water and wind-induced physical turbulence in coastal waters. Her work on the role of plankton groups on CO2 dynamics indicated that diatoms are key contributors to atmospheric CO2 uptake in surface waters, providing a direct link between biodiversity and climate- relevant processes.
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Bebout B.M., Garcia-Pichel F., UV B-Induced Vertical Migrations of Cyanobacteria in a Microbial Mat, Appl. Environ. Microbiol., Dec 1995, 4215–4222, Vol 61, No. 12 Microbial mats are generally held together and bound to their substrates by slimy extracellular polymeric substances which they secrete. In many cases some of the bacteria form filaments (threads), which tangle and thus increase the colonies' structural strength, especially if the filaments have sheaths (tough outer coverings). This combination of slime and tangled threads attracts other microorganisms which become part of the mat community, for example protozoa, some of which feed on the mat-forming bacteria, and diatoms, which often seal the surfaces of submerged microbial mats with thin, parchment-like coverings.
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Cyst of a dinoflagellate Peridinium ovatum Dinoflagellates occur in most aquatic environments and during their life cycle, some species produce highly resistant organic-walled cysts for a dormancy period when environmental conditions are not appropriate for growth. Their living depth is relatively shallow (dependent upon light penetration), and closely coupled to diatoms on which they feed. Their distribution patterns in surface waters are closely related to physical characteristics of the water bodies, and nearshore assemblages can also be distinguished from oceanic assemblages. The distribution of dinocysts in sediments has been relatively well documented and has contributed to understanding the average sea-surface conditions that determine the distribution pattern and abundances of the taxa ().
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Endosymbiotic gene transfer is how we know about the lost chloroplasts in many CASH lineages. Even if a chloroplast is eventually lost, the genes it donated to the former host's nucleus persist, providing evidence for the lost chloroplast's existence. For example, while diatoms (a heterokontophyte) now have a red algal derived chloroplast, the presence of many green algal genes in the diatom nucleus provide evidence that the diatom ancestor had a green algal derived chloroplast at some point, which was subsequently replaced by the red chloroplast. In land plants, some 11–14% of the DNA in their nuclei can be traced back to the chloroplast, up to 18% in Arabidopsis, corresponding to about 4,500 protein-coding genes.
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The geologists began microscopic and chemical examination of the sand to determine types and distribution of diatoms and other microscopic sea creatures, and its mineral composition. They determined that the sand could not be coming from American beaches, nor from the mid-Pacific. It had to be coming from Japan. The geologists ultimately determined the precise beaches in Japan where the sand had been taken.Whitmore, Frank C., Jr. 1954. “Military Geology.” The Military Engineer, Volume XLVI, number 311, pages 212-215C; M. Nelson and E. P. F. Rose. 2012. "The U. S. Geological Survey's Military Geology Unit in World War II: the Army's pet prophets." Quarterly Journal of Engineering Geology and Hydrogeology (August 2012), 45(3):349-367.
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Currently, cyanobionts have been found to form symbiosis with various organisms in marine environments such as diatoms, dinoflagellates, sponges, protozoans, Ascidians, Acadians, and Echiuroid worms, many of which have significance in maintaining the biogeochemistry of both open ocean and coastal waters. Specifically, symbioses involving cyanobacteria are mostly mutualistic, in which the cyanobionts are responsible for nutrient provision to the host in exchange for attaining high structural-functional specialization. Most cyanobacteria-host symbioses are found in oligotrophic areas where limited nutrient availability may limit the ability of the hosts to acquire carbon (DOC), in the case of heterotrophs and nitrogen in the case of phytoplankton, although a few occur in nutrient-rich areas such as mudflats.
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Diatom DNA barcoding A newly applied method is diatom DNA metabarcoding which is used for ecological quality assessment of rivers and streams because of the specific response of diatoms to particular ecologic conditions. As species identification via morphology is relatively difficult and requires a lot of time and expertise, high-throughput sequencing (HTS) DNA metabarcoding enables taxonomic assignment and therefore identification for the complete sample regarding the group specific primers chosen for the previous DNA amplification. Until now, several DNA markers have already been developed, mainly targeting the 18S rRNA. Using the V4 hypervariable region of the ribosomal small subunit DNA (SSU rDNA), DNA-based identification was found to be more efficient then the classical morphology based approach.
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In contrast, parts of the southern Delta have a higher residence time due to the low volume of water moving through the system; in fact the water on occasion runs backwards, due to the lack of inflow from the San Joaquin River, and export pumping. During summer, phytoplankton density may be an order of magnitude higher here than in other parts of the estuary.Ball and Arthur 1979 Harmful algal blooms (HAB's) of dinoflagellates or cyanobacteria produce toxic metabolic byproducts that render them noxious to many organisms. Fostered by a combination of high nutrient concentrations and temperatures, HAB's have a doubly negative effect on the food web by competitively excluding diatoms and microflagellates, further reducing bioavailable primary production.
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Molecular analyses in modern taxonomy have been used to redistribute former members of this group into diverse and sometimes distantly related phyla. For instance, the water molds are now considered to be closely related to photosynthetic organisms such as Brown algae and Diatoms, the slime molds are grouped mainly under Amoebozoa, and the Amoebozoa itself includes only a subset of the "Amoeba" group, and significant number of erstwhile "Amoeboid" genera are distributed among Rhizarians and other Phyla. However, the older terms are still used as informal names to describe the morphology and ecology of various protists. For example, the term protozoa is used to refer to heterotrophic species of protists that do not form filaments.
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They are translucent at this stage and remain at sea for somewhere between 133 and 256 days before getting the urge to migrate back into fresh water. The post-larval stage starts as they enter estuaries. They have already developed suction discs, but now they undergo metamorphosis, their mouths move from the tip of the snout to the underneath of the head, they begin to develop pigment, the pectoral fins transform, the tail loses its fork, they grow teeth on the premaxillae bone, changes occur in the cranium and changes in osmoregulation take place. As the rake-like teeth push through, they start to feed on diatoms and algae that they scrape off the substrate.
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This snail is found frequently on rocks in the low intertidal zone and in the shallow subtidal zone on large kelp, especially the giant kelp Macrocystis. Calliostoma eats a variety of items including the kelp it lives on as well as small sessile organisms and other material that live on rocks or kelp surfaces, including bryozoans, hydroids, diatoms, and detritus. This snail shows a remarkable range of behavioral reactions to other animals. Snails displayed a flight response with movement rates up to 10 cm/min, often accompanied by shell twisting, between 70% and 100% of the time after contact with the following predatory seastars: Leptasterias hexactis, Pycnopodia helianthoides, Pisaster ochraceus, and Evasterias troscheli.
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In marine environments, HABs are mostly caused by dinoflagellates,Stewart I and Falconer IR (2008) "Cyanobacteria and cyanobacterial toxins" Pages 271–296 in Oceans and human health: risks and remedies from the seas, Eds: Walsh PJ, Smith SL and Fleming LE. Academic Press, . though species of other algae taxa can also cause HABs (diatoms, flagellates, haptophytes and raphidophytes).Moestrup Ø, Akselman R, Cronberg G, Elbraechter M, Fraga S, Halim Y, Hansen G, Hoppenrath M, Larsen J, Lundholm N, Nguyen LN and Zingone A. "IOC-UNESCO Taxonomic Reference List of Harmful Micro Algae (HABs)" Accessed 21 January 2011. Marine dinoflagellate species are often toxic, but freshwater species are not known to be toxic.
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There was something very different about the Ediacaran Period that permitted these delicate creatures to be left behind and it is thought the fossils were preserved by virtue of rapid covering by ash or sand, trapping them against the mud or microbial mats on which they lived. Their preservation was possibly enhanced by the high concentration of silica in the oceans before silica-secreting organisms such as sponges and diatoms became prevalent. Ash beds provide more detail and can readily be dated to the nearest million years or better using radiometric dating. However, it is more common to find Ediacaran fossils under sandy beds deposited by storms or high-energy bottom-scraping ocean currents known as turbidites.
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One local newspaper editor theorized that Cooper, knowing he could never spend the money, dumped it in the river, or buried portions of it at Tena Bar (and possibly elsewhere) himself. No hypothesis offered to date satisfactorily explains all of the existing evidence. Analysis of diatom samples on the money, which are small algae found in water and soil, suggests that the bundles found at Tina Bar could not have been submerged in the river or buried dry at the time of the hijacking in November 1971, as only diatoms that bloom during springtime were found, placing the date range that the money entered the water at least several months after the hijacking.
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Diatomaceous earth consists of fossilized remains of diatoms, a type of hard-shelled protist. It is used as a filtration aid, mild abrasive in products including metal polishes and toothpaste, mechanical insecticide, absorbent for liquids, matting agent for coatings, reinforcing filler in plastics and rubber, anti-block in plastic films, porous support for chemical catalysts, cat litter, activator in blood clotting studies, a stabilizing component of dynamite, a thermal insulator, and a soil for potted plants and trees like bonsai. bright field illumination on a light microscope. This image of diatomaceous earth particles in water is at a scale of 6.236 pixels/μm, the entire image covering a region of approximately 1.13 by 0.69 mm.
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They have been recorded at up to 55 cm in length. Unlike most North American cyprinids, they feed on zooplankton, planktonic algae, and floating detritus, including rotifers, copepods, cladocerans, diatoms, and the like. Younger fish pick at food items individually, while adults work by pumping large amounts of water through the oral cavity; the food bits are caught in a patch of mucus on the roof of the mouth, where it is secreted by a special organ, and then the fish swallows mucus and food together. Blackfish are primarily denizens of the warm turbid waters found on the floor of the Central Valley, such as sloughs and oxbow lakes connected to the Sacramento and San Joaquin Rivers.
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For references, the osmolarity of seawater is on average, 1 Osm/L. Marine diatoms and algae in general tend to flourish in higher osmolar concentrations due to the increased presence of carbon dioxide and nutrients to be utilized as sustenance, but the low-solute environment Schobert found to be most optimal for the growth of C. meneghiana is consistent with most Cyclotella being found in low-productivity mesotrophic to oligotrophic environments. Species of cyclotella have been found in harsh aquatic environments such as coldwater regions in northern regions of the world. Another study by Van de Vijver and Dessein found a new species of Cyclotella, C. deceusteriana, in the sub-antarctic region.
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Poropuntius deauratus is a species of ray-finned fish in the genus Poropuntius which is found in coastal river drainages in central Vietnam: between the Thu Bon River in Quang Nam Province and the Quang Tri River in Quang Tri Province. There was a marked decline in this species' abundance between 2-000 and 2009 when the population may have declined by as much as 80%, this decline was probably caused by overfishing. Its habitat is medium and small sized rivers and streams where it is normally found in fast-flowing, clear water and it cannot survive where these are impounded. It diet mainly consists of fine debris, algae, diatoms, and aquatic insects.
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In the nymphs of most mayfly species, the paddle-like gills do not function as respiratory surfaces because sufficient oxygen is absorbed through the integument, instead serving to create a respiratory current. However, in low-oxygen environments such as the mud at the bottom of ponds in which Ephemera vulgata burrows, the filamentous gills act as true accessory respiratory organs and are used in gaseous exchange. In most species, the nymphs are herbivores or detritivores, feeding on algae, diatoms or detritus, but in a few species, they are predators of chironomid and other small insect larvae and nymphs. Nymphs of Povilla burrow into submerged wood and can be a problem for boat owners in Asia.
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Warming also reduces nutrient levels in the mesopelagic zone (about 200 to 1000 m deep). This in turn limits the growth of diatoms in favour of smaller phytoplankton that are poorer biological pumps of carbon. This inhibits the ability of the ocean ecosystems to sequester carbon as the oceans warm. What is clear, is that healthy ocean and coastal ecosystems are necessary to continue the vital role of the ocean carbon sinks, as indicated, for example, by the Blue Carbon assessment prepared by UNEP and the coastal carbon sinks report of IUCN and growing evidence of the role of fish biomass in the transport of carbon from surface waters to the deep ocean.
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Many researchers have been unwilling to recognize the Mastogloia Sea as a separate stage in the development of the Baltic Sea, favouring including it in either the Ancylus Lake stage or the Littorina Sea stage.Hyvärinen et al. 1988.Miettinen 2002 In stratigraphy of Baltic sediments the Mastogloia stage is difficult to detect, its sediments being visibly identical to those of the Ancylus Lake.Donner 1995Eronen 1983 Even the fossil diatom content of the phase's sediments - cited by researchers as the key method of distinguishing deposits of different Baltic stages - is ambiguous, in many places showing no difference from that of Ancylus deposits, and at best including an admixture of Mastogloia diatoms in an otherwise typical Ancylus flora.
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The species is herbivorous, grazing on marine algae. It mostly feeds on the red leafy alga Acrosorium polyneurum between December and March at the times of year when it is abundant, and migrating to areas of crustose coralline algae at other times of year when the red alga is scarce. As is the case with other sea urchins, H. pulcherrus liberates eggs and sperm into the water column and the echinopluteus larvae spend several months drifting with the plankton. They are stimulated to settle on the seabed by the attachment of diatoms and by the presence in the water of particles of an alga such as Hizikia fusiformis which grows around the coasts of Japan.
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Another sea cucumber, Holothuria leucospilota, also acts as a host to the bivalve but of 30 specimens collected from the same locality, only one was found to harbour any of them, and that one contained just 5 molluscs. It was at first surmised that Entovalva nhatrangensis might absorb nutrients through its epithelium. This idea was rejected however because the surface of the mantle is covered by a thin cuticle, which would make absorption difficult. The stomach was found to contain diatoms, therefore it is likely that the bivalve uses its gills to filter them and other fine organic particles from the contents of the sea cucumber's gut in which it is immersed.
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Tip of arm showing eyespot Asterina gibbosa is mainly nocturnal, spending the day underneath boulders, overhangs or in caves, or hidden away under algae in rock pools. It is an opportunistic scavenger but the bulk of its diet comes from the film of bacteria and diatoms that exist on the surface of rocks. It feeds by everting its stomach (turning it inside out) against the surface of the rock and secreting enzymes which digest the film. Other foods found in its stomach included decaying toothed wrack (Fucus serratus), periwinkle faeces and bits of dead molluscs such as mussels (Mytilus edulis), oysters (Ostrea edulis) and periwinkles (Littorina littorea), but 95% of the stomachs contained no large particles indicating the importance in its diet of microscopic organisms.
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Wickramasinghe claimed that these microorganisms constitute strong evidence for panspermia, On 15 January 2013 a diatom expert, Patrick Kociolek, verified that the forms pointed out in the paper are indeed diatoms. Then he added: Meanwhile, PZ Myers, who studies evolutionary developmental biology, questions "why a space organism would evolve to look exactly like a species that evolved in a completely different environment, and how it could have converged in all its details on such remarkable similarity to a specific Earthly species? Why, we might even suggest that it clearly looks like contamination." While ignoring the environmental influence in evolution, a proponent of the panspermia hypothesis, Brig Klyce, contends that since life on Earth and life from space are closely related, resemblance would be expected.
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Leptopentacta elongata is a suspension feeder, consuming diatoms, single-cell algae and organic particles, as well as zooplankton, such as copepods, ostracods, protozoans, nematodes, jellyfish and larvae. It uses its eight feeding tentacles to gather particles, each shrinking and bending, in an apparently random order, to transfer the food to the mouth. The two ventral tentacles are used in coordination with the other tentacles, being folded around the feeding tentacles so that the forks scrape off the food fragments when the larger tentacles are withdrawn from the mouth; in some other sea cucumbers with similar feeding habits, such as Pawsonia saxicola, the forked tentacles seem to act entirely independently and do not coordinate their actions with the larger tentacles. This sea cucumber can hibernate in the winter.
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The rosyface shiner is an omnivorous fish and has been reported to eat insects such as caddis fly larvae, mayfly nymphs, diptera, fish eggs, algae, diatoms, and other organic material, although insects make up a large majority of its diet. They are known to feed on insects on the surface of the water including terrestrial insects that fall into the water, but will also feed in mid-waters as well. They have even been known to jump out of the water to capture flying insects. In a study conducted by Roger J. Reed in 1957 rosyface shiners were reported to have 20% of fish with full stomachs during the months of late April to late May during pre-spawning activities.
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Becoming interested in science he joined the Field Naturalists Club of Victoria, studied botany and did some work on the diatoms, a group of minute plants. Grayson attended meetings of the Royal Microscopical Society and developed a talent for preparing microscope slides. Before 1894 he had constructed a machine for making micrometer rulings on glass, the results being very good for that time. In 1897 some beautiful work Grayson had done in cutting sections of plants led to his being given a position in the physiology department of the University of Melbourne under Professor C. J. Martin. He was afterwards transferred to the geology department, and in December 1901 accompanied Professor F. T. Gregory on his expedition to Central Australia.
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A clear paleontological window on cyanobacterial evolution opened about 2000 Ma, revealing an already-diverse biota of Cyanobacteria. Cyanobacteria remained the principal primary producers of oxygen throughout the Proterozoic Eon (2500–543 Ma), in part because the redox structure of the oceans favored photoautotrophs capable of nitrogen fixation. Green algae joined cyanobacteria as the major primary producers of oxygen on continental shelves near the end of the Proterozoic, but it was only with the Mesozoic (251–66 Ma) radiations of dinoflagellates, coccolithophorids, and diatoms did the primary production of oxygen in marine shelf waters take modern form. Cyanobacteria remain critical to marine ecosystems as primary producers of oxygen in oceanic gyres, as agents of biological nitrogen fixation, and, in modified form, as the plastids of marine algae.
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From January to March 2013, five papers were published in the fringe Journal of Cosmology outlining various results from teams in the United Kingdom, United States and Germany. However, independent experts in meteoritics stated that the object analyzed by Wickramasinghe's team was of terrestrial origin, a fulgurite created by lightning strikes on Earth. Experts in diatoms complemented the statement, saying that the organisms found in the rock represented a wide range of extant terrestrial taxa, confirming their earthly origin. Wickramasinghe and collaborators responded, using X-ray diffraction, oxygen isotope analysis, and scanning electron microscope observations, in a March 2013 paper asserting that the rocks they found were indeed meteorites, instead of being created by lightning strikes on Earth as stated by scientists from the University of Peradeniya.
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The application of flow cytometry to environmental samples led Chisholm and her collaborators (most notably R.J. Olson and H.M. Sosik) to the discovery that small plankton (in particular Prochlorococcus and Synechococcus) accounted for a much more substantial part of marine productivity than had previously been realized. Previously, biological oceanographers had focused on silicaceous diatoms as being the most important phytoplankton, accounting for 10-20 gigatons of carbon uptake each year. Chisholm's work showed that an even larger amount of carbon was cycled through these small algae, which may also play an important role in the global nitrogen cycle. In recent years, Chisholm has played a visible role in opposing the use of iron fertilization as a technological fix for anthropogenic climate change.
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Genetic and ultrastructural evidence place the Phaeophyceae among the heterokonts (Stramenopiles), a large assemblage of organisms that includes both photosynthetic members with plastids (such as the diatoms) as well as non-photosynthetic groups (such as the slime nets and water molds). Although some heterokont relatives of the brown algae lack plastids in their cells, scientists believe this is a result of evolutionary loss of that organelle in those groups rather than independent acquisition by the several photosynthetic members. Thus, all heterokonts are believed to descend from a single heterotrophic ancestor that became photosynthetic when it acquired plastids through endosymbiosis of another unicellular eukaryote. The closest relatives of the brown algae include unicellular and filamentous species, but no unicellular species of brown algae are known.
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The port of Poti, Georgia The Black Sea supports an active and dynamic marine ecosystem, dominated by species suited to the brackish, nutrient-rich, conditions. As with all marine food webs, the Black Sea features a range of trophic groups, with autotrophic algae, including diatoms and dinoflagellates, acting as primary producers. The fluvial systems draining Eurasia and central Europe introduce large volumes of sediment and dissolved nutrients into the Black Sea, but the distribution of these nutrients is controlled by the degree of physiochemical stratification, which is, in turn, dictated by seasonal physiographic development. During winter, strong wind promotes convective overturning and upwelling of nutrients, while high summer temperatures result in a marked vertical stratification and a warm, shallow mixed layer.
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Although grazing is typically associated with mammals feeding on grasslands, ecologists sometimes use the word in a broader sense, to include any organism that feeds on any other species without ending the life of the prey organism. Use of the term "grazing" varies further; for example, a marine biologist may describe herbivorous sea urchins that feed on kelp as grazers, even when they kill the organism by cutting the plant at the base. Malacologists sometimes apply the word to aquatic snails that feed by consuming the microscopic film of algae, diatoms and detritus—a biofilm—that covers the substrate and other surfaces underwater. In marine ecosystems, grazing by mesograzers such as some crustaceans maintains habitat structure by preventing algal overgrowth, especially in coral reefs.
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Endosymbiotic gene transfer is how we know about the lost chloroplasts in many chromalveolate lineages. Even if a chloroplast is eventually lost, the genes it donated to the former host's nucleus persist, providing evidence for the lost chloroplast's existence. For example, while diatoms (a heterokontophyte) now have a red algal derived chloroplast, the presence of many green algal genes in the diatom nucleus provide evidence that the diatom ancestor (probably the ancestor of all chromalveolates too) had a green algal derived chloroplast at some point, which was subsequently replaced by the red chloroplast. In land plants, some 11–14% of the DNA in their nuclei can be traced back to the chloroplast, up to 18% in Arabidopsis, corresponding to about 4,500 protein-coding genes.
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E. crystallorophias feeds on bacteria, diatoms, detritus, and other microorganisms, including the algae that form on the underside of sea ice, and is in turn an important food source for fish, whales, and penguins, especially minke whales, Weddell seals, Adelie penguins, and the Antarctic silverfish. This makes it arguably the most important link in the coastal Antarctic food chain between the primary producers and the macrofauna. Unlike most other krill species, the eggs of E. crystallorophias are neutrally buoyant, meaning they do not sink, and the hatchling larvae do not have to swim back to the more productive, shallower waters; however, since this means both life stages inhabit the same depths, how the larvae avoid being eaten by the adults is not known.
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The parasitic dinoflagellate Hematodinium however lacks a plastid entirely. Some groups that have lost the photosynthetic properties of their original red algae plastids has obtained new photosynthetic plastids (chloroplasts) through so-called serial endosymbiosis, both secondary and tertiary. Like their original plastids, the new chloroplasts in these groups can be traced back to red algae, except from those in the members of the genus Lepidodinium, which possess plastids derived from green algae, possibly Trebouxiophyceae or Ulvophyceae. Lineages with tertiary endosymbiosis are Dinophysis, with plastids from a cryptomonad,The toxic dinoflagellate Dinophysis acuminata harbors permanent chloroplasts of cryptomonad origin, not kleptochloroplasts the Karenia, Karlodinium, and Takayama, which possess plastids of haptophyte origin, and the Peridiniaceae, Durinskia and Kryptoperidinium, which has plastids derived from diatoms Some species also perform kleptoplasty.
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Even since 1926, records of the white line and associated features have been taking place. In that year an unnamed ocean explorer described the white line and its collection of diatoms as having the consistency of soup due to the abundance of ocean fauna. In these early days scientists were able to discover the time at which the line formed (between January and August, as mentioned earlier). During a 10-year international study called the Joint Global Ocean Flux Study the white line was photographed for the first time, as the scientists were studying how currents, chemicals, ocean color, and temperature affected the overall ocean and it was during this study that the line was photographed and the scale of the event was discovered, by the Space Shuttle.
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Sea foam usually contains a mixture of decomposed organic materials The composition of sea foam is generally a mixture of decomposed organic materials, including zooplankton, phytoplankton, algae (including diatoms), bacteria, fungi, protozoans, and vascular plant detritus, though each occurrence of sea foam varies in its specific contents. In some areas, sea foam is found to be made up of primarily protein, dominant in both fresh and old foam, as well as lipids and carbohydrates. The high protein and low carbohydrate concentration suggest that sugars originally present in the surrounding mucilage created by algae or plant matter has been quickly consumed by bacteria. Additional research has shown that a small fraction of the dry weight in sea foam is organic carbon, which contains phenolics, sugars, amino sugars, and amino acids.
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Although no mass extinctions of marine diatoms have been observed during the Cenozoic, times of relatively rapid evolutionary turnover in marine diatom species assemblages occurred near the Paleocene–Eocene boundary, and at the Eocene–Oligocene boundary. Further turnover of assemblages took place at various times between the middle Miocene and late Pliocene, in response to progressive cooling of polar regions and the development of more endemic diatom assemblages. A global trend toward more delicate diatom frustules has been noted from the Oligocene to the Quaternary. This coincides with an increasingly more vigorous circulation of the ocean's surface and deep waters brought about by increasing latitudinal thermal gradients at the onset of major ice sheet expansion on Antarctica and progressive cooling through the Neogene and Quaternary towards a bipolar glaciated world.
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The complex structure of their microscopic shells has been proposed as a material for nanotechnology. Diatomite is considered to be a natural nano material and has many uses and applications such as: production of various ceramic products, construction ceramics, refractory ceramics, special oxide ceramics, for production of humidity control materials, used as filtration material, material in the cement production industry, initial material for production of prolonged-release drug carriers, absorption material in an industrial scale, production of porous ceramics, glass industry, used as catalyst support, as a filler in plastics and paints, purification of industrial waters, pesticide holder, as well as for improving the physical and chemical characteristics of certain soils, and other uses. Diatoms are also used to help determine the origin of materials containing them, including seawater.
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Giant girdled lizard Robinson was born in Elliot, South Africa to Theodore Clement Robinson and Florence Harriett Robinson (née Selby), both descendants of the British 1820 Settlers. He attended the University of Cape Town where he obtained a BSc in zoology and bacteriology in 1943 and an MSc (zoology) in 1944, with a thesis on the giant girdled lizard (Cordylus giganteus). He contributed to two dissection manuals, one on the clawed frog (Xenopus) and the other on the spiney dogfish shark (Squalus). He started his doctorate in marine biology in Cape Town and even went so far as to publish descriptions of new diatoms and copepods but he interrupted it by moving to the Transvaal Museum in Pretoria at the end of 1945 to take up the position of "assistant professional officer".
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Settling rates for algae, other than diatoms, are slow. Slow settling rates allow for algae to remain in the water column longer, allowing for increased release for organically bound phosphorus and nitrogen into the water column through remineralization. The combine impact of increased silicate retention and increased remineralization of phosphorus and nitrogen can result in high N/Si and P/Si ratios within and below reservoirs; these increased rations can be further compounded by increase nitrogen and phosphorus concentrations from eutrophication. The high N/Si and P/Si rations caused by these processes can be harmful to the local ecosystem in the basin; for example, N/Si ratios greater than 1 can result in excess nitrogen relative to diatom requirements, this can promote the growth of other phytoplankton species, negatively affecting diatom communities.
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Population density: The subtidal population density of Margarites pupillus in the San Juan Islands, WA, USA, is linked to the abundance of kelp, primarily Agarum fimbriatum. Densities of over 400 snails per square meter can occur where kelp density provides 100% bottom cover, and snail density declines to only a few snails per square meter below the algal zone. Diet: This snail is a generalist grazer; gut contents showed that the digestive tract of all snails examined contained unidentifiable detritus and silt and sand, 94% contained unidentified filamentous red algae, 86% contained diatoms, 79% contained sponge spicules, 64% contained filamentous brown algae, 21% contained remains of hydroids, 14% had remains of bryozoans, and 7% contained filamentous green algae. There was no evidence that M. pupils feeds on Agarum on which it lives.
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It was observed that the clay formed quickly, and using this amount of time and the known content of the sediment, concentration of potassium ions consumed by this process in rivers around the globe was estimated. Laboratory experiments can also include incubation experiments, in which sediment samples obtained from natural environments are enclosed in sealable containers with varied concentrations reverse weathering reactants (biogenic silica in the form of diatoms, cations, metals, etc.). 250x250px Using an inductively coupled plasma optical emission spectrometer (ICP-OES) also provides concentration and isotopic information for cation and silica concentrations in pore water and digested sediment samples. Utilization of a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) is also used as a means of obtaining isotopic data of metals and silica in solution.
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EMBL light microscopy facility, shows a group of diatoms with cyan cell walls, red chloroplasts, blue DNA, and green membranes and organelles Four types of confocal microscopes are commercially available: Confocal laser scanning microscopes use multiple mirrors (typically 2 or 3 scanning linearly along the x- and the y- axes) to scan the laser across the sample and "descan" the image across a fixed pinhole and detector. Spinning-disk (Nipkow disk) confocal microscopes use a series of moving pinholes on a disc to scan spots of light. Since a series of pinholes scans an area in parallel, each pinhole is allowed to hover over a specific area for a longer amount of time thereby reducing the excitation energy needed to illuminate a sample when compared to laser scanning microscopes. Decreased excitation energy reduces phototoxicity and photobleaching of a sample often making it the preferred system for imaging live cells or organisms.
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The area surrounding the lake was once well-forested with Atlas cedar (Cedrus atlantica), but more recently, this forest has become degraded and the area around the lake has become dry, thorny scrubland dominated by Spanish juniper (Juniperus thurifera). The plankton and sediment in the lake is rich in diatoms, particularly of the genus Cyclotella, and these have been used to provide evidence of the paleohydrology and related hydroclimatic changes the lake has undergone over the aeons. In 2005, the Aguelmams Sidi Ali / Tifounassine complex, three mountain wetlands at altitudes between , have been designated as a Ramsar site; they provide important over-wintering sites for migratory wetland birds including the ruddy shelduck (Tadorna ferruginea) and the crested coot (Fulica cristata). A decreasing trend in precipitation has lowered the water level of the lake, and a marsh that used to be at the southwest end no longer exists.
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Micromonas species still share the same collection of photosynthetic pigments as the members of the class Mamiellophyceae, which includes the common pigments chlorophyll a and chlorophyll b, as well as prasinoxanthin (xanthophyll K), the first algal carotenoid being assigned with a structure that has a γ-end group. It has been discovered that most of its xanthophylls are in the oxidized state and show similarities to ones possessed by other important marine planktons like diatoms, golden and brown algae, and dinoflagellates. In addition, there is another pigment called Chl cCS-170 can be found in some strains of Micromonas and Ostreococcus living in deeper part of the ocean, which may indicate a potential adaptation for organisms that reside under low light intensity. The light-harvesting complexes of Micromonas are distinguishable from other green algae in terms of pigment composition and stability under unfavorable conditions.
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Structure of silane, analog of methane Structure of the silicone polydimethylsiloxane (PDMS) Marine diatoms—carbon-based organisms that extract silicon from sea water, in the form of its oxide (silica) and incorporate it into their cell walls The silicon atom has been much discussed as the basis for an alternative biochemical system, because silicon has many chemical properties similar to those of carbon and is in the same group of the periodic table, the carbon group. Like carbon, silicon can create molecules that are sufficiently large to carry biological information. However, silicon has several drawbacks as an alternative to carbon. Silicon, unlike carbon, lacks the ability to form chemical bonds with diverse types of atoms as is necessary for the chemical versatility required for metabolism, and yet this precise inability is what makes silicon less susceptible to bond with all sorts of impurities from which carbon, in comparison, is not shielded.
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Notably, while the species mentioned above are all relatively close taxonomic relatives (in the Fungi/Metazoa group), P. infestans has a distinct evolutionary history; it is classified as an oomycete, and is a member of the Kingdom Stramenopila (the Heterokonts in some schemes) along with diatoms and brown algae. The single Cdc14 gene of P. infestans (PiCdc14) is expressed distinctly from those of fungi and metazoans; instead of being transcribed throughout the cell cycle and regulated post- translationally, PiCdc14 is under strong transcriptional control and is not expressed in hyphae, where most mitosis takes place. Instead, PiCdc14 is made during the formation of asexual spores, including its biflagellated zoospores. PiCdc14 was found to accumulate near the basal bodies, at the base of the flagella. In light of the varying roles of Cdc14 in fungi and animals, it was suggested that the P. infestans data implied that an ancestral role of Cdc14 involved the flagella stage of eukaryotes.
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The vegetation, identified by the pollen at different levels, shows the evolution of the paleoenvironment during the sedimentation of the same, which in general corresponds to fluvio-lacustrine media under a temperate climate, softer and more humid than the current one. For the lower sections of the sequence (AS1 to AS5) an initial environment is inferred with grasses, riparian trees (alder, willow and elm) and few pines, after which an environment of moorland with junipers, alternating, with an increase towards the end, with pine forests. The AS6 level is characterized by the almost exclusive domain of the pine forests, but on the roof, the return of the moorlands is finally reflected with junipers and grasses (Poaceae). The diatoms indicate that during the sedimentation of the AS4 and AS5 units the salinity increased in the lagoon and that the water layer was somewhat higher with respect to the previous units -the salts would be contributed by the sediments of the underwater Keuper facies that surround all area-.
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After finishing his education, he settled and worked in Skoraszewice, Piotrowo, Pempowo and Sypniewo (all within his family's vast estate at that time), where he worked on natural history in general, and published multiple studies and expertises in entomology, malacology and algology, as well as occasional medical and philosophical treatises, among many others. In his later years, he focused on studying algaes and seaweed. For his scientific work on diatoms he was offered the position of Dean of Zoology at the Jagiellonian University, the most renowned and oldest of Polish universities. He was one of the founders and unanimously elected the President of the Faculty of Natural Sciences of the Poznańskie Towarzystwo Przyjaciół Nauk (PTPN), renowned Polish Society of Science (and the only Polish such society allowed to exist in occupied Poland at that time - hence its name "Poznańskie" - which means "of Poznan city" - instead of "Polish", since the term "Polish" was forbidden under the German occupation laws).
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Johad at Rithal village of Rohtak district of Haryana In 2007, Haryana Irrigation Department spent INR435.26 crore (INR4.3 billion or US$7 million) to renovate and restore water bodies in the state for the conservation of water, recharging of ground water, preservation of environment and enhancement of tourism. A study by the Panjab University found 60 fish species of 19 families, 11 commercial and 6 exotic species, in the water bodies of Haryana. Water bodies remain under risk from encroachment, shrinking of catchment area and pollution. In 2010, India's first ever diatom data basing was done in ten different water bodies at ten different stations in Haryana. A 2015 study of 24 water bodies of Haryana, found 39 morphologically different types of diatoms. In 2016, the Government of Haryana announced a plan to map the district-wise map of water flow and to create a database of all water bodies within the state.
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