146 Sentences With "fossilize" | Random Sentence Generator

Tumors, malignant and benign, typically involve soft tissue, and rarely fossilize.

I was scared it might fossilize there and become permanently embedded.

As noted, baleen, which is made from soft tissue, doesn't fossilize very well.

Soft tissue is much harder to find because it does not fossilize easily.

"One morning this sadness will fossilize / And I'll forget how to cry," she sings.

The structures that support language don't fossilize, so evidence is simply harder to come by.

But sometimes conditions prevail that protect the more delicate organs, allowing them to fossilize as well.

One is that male specimens are possibly easier to fossilize by virtue of their larger size.

These soft-bodied specimens typically don't fossilize well, but the ones he collected were pristinely preserved.

Somehow, the fossilization environment has to percolate down and get minerals to the bones to fossilize them.

Shoulder blades are an incredibly rare find because they're delicate, almost paper thin, and don't usually fossilize.

Studying primitive spiders is tricky because they lack an internal skeleton, which means they don't fossilize well.

He lobs the ball into the tar pit where it will fossilize and remain for millennia to come.

Perhaps the earliest animals were simply too small and could only fossilize under certain circumstances, though this is speculative.

You need just the right circumstances to fossilize something like a school of fish in place within a rock.

"But it's very rare for things to fossilize," he said, noting that anything dead has to be buried quickly.

Though it's unclear how thick dinosaur skin was (flesh doesn't fossilize), we now know that certain dinosaurs, like Velociraptors, had feathers.

Animals this small do not fossilize well, which is why this stage of the distant evolutionary past is so little known.

"It didn't make sense to us that there would be this one animal that would fossilize its gut completely differently," she said.

Unfortunately, these feathered creatures, with their brittle and easily breakable bones, don't fossilize well, and there's a frustrating fossil gap around this time.

The syrinx is hard to find in ancient bird specimens because it is made of calcified cartilage that does not typically fossilize well.

This paper, he says, is more a proof of concept: Tissues as soft and squishy as brains can, under the right circumstance, fossilize.

Kern, who is infatuated with nostalgic memorabilia, created these prehistoric pieces as an attempt to "fossilize" the pop culture influences of his youth.

There had been a paucity of pterosaur eggs and embryos in the paleontological record because it is difficult for soft-shelled eggs to fossilize.

Much of our knowledge of the Megalodon are derived from their teeth, since the sharks' cartilage-based skeletons were not preserved since cartilage doesn't fossilize like bone.

Finding teeth are important for understanding how ancient sharks lived, as the majority of their bodies are made up of cartilage, which unlike bones, does not fossilize.

Because shark skeletons are made of soft cartilage, which doesn't fossilize well, most of what scientists know about ancient sharks comes from teeth, scales and fin spine fossils.

But for reasons still unknown, a couple of these spiders did fossilize, and the unique shape of their eye structures continue to reflect light — even in their petrified form.

CATFISHES, ONION TART, OOPS SORRY, the fabulous book series and film CRAZY RICH ASIANS, ALL PROS, the much-missed GWEN IFILL, FOSSILIZE and INSANELY all make their New York Times Crossword debuts today.

Guts don't fossilize, so paleontologists have had to rely on the evolutionary record of teeth and jaws in human ancestors to figure out this history, along with comparisons to our modern-day cousins, apes.

Hearts, however, "do not fossilize," Dr. Lieberman says, so the best way to learn about their evolution would be not through excavations but via comparative appraisals of our organs with those of our erstwhile relatives.

Even a fragile macaron, which looks like it might fossilize within an hour of existence, must be left a day or two after baking to give it that classic seesaw of crackle and deflation, shatter and chew.

"There are dozens of superficial correlations involving language which are spurious, and linguistic behavior, such as pronunciation, doesn't fossilize," said Damián Blasi, study author and postdoctoral researcher in the University of Zurich's Comparative Linguistics Department, in a statement.

Of course, flight motion itself does not fossilize, and the flight pattern of Archaeopteryx cannot be studied in a living animal anymore, which makes determining flight style even more difficult, lead study author Dennis Voeten wrote in an email.

For almost all known titanosaurs, paleontologists have fossils of parts of the body like leg bones that are taller than a person, but no pieces of the skull, which consisted of bones that were thinner, more delicate, and less likely to fossilize.

And one of this album's standouts is the controlledly tense "Fireworks," an ode to stoic forgetting, to the need to remain implacable in the face of devastation: One morning this sadness will fossilize and I will forget how to cryI'll keep going to workand you won't see a changesave perhaps a slight gray in my eyeI will go jogging routinelycalmly and rhythmically runand when I find that a knife's sticking out of my side I'll pull it out without questioning why.

Contemporary local plants also left behind leaves that would later fossilize.

At this point the local Rocky Mountains began to rise. During the Cretaceous cephalopods with coiled shells and clams were preserved at Monument Creek. Fish were present in Coloradan waters and left behind scales that would later fossilize. On land the flora also left behind leaves that would later fossilize.

Orenda Spring has created a massive tufa dome, which continues to fossilize leaves and other debris as it grows.

As a cartilaginous fish, shark tissues usually do not fossilize. Squalus acanthias fossils date back to the Miocene 11 MYA.

Sea levels also rose and fell during the ensuing Paleogene period of the Cenozoic era. Inhabitants of the sea would sometimes fossilize in the state.

Soft-bodied organisms today rarely fossilize during such events, but the presence of widespread microbial mats probably aided preservation by stabilising their impressions in the sediment below.

Local plants left behind leaves that would later fossilize. Local insect life also left behind fossils. Dinosaurs inhabited the region, leaving behind both footprints and bones. American mastodon.

Mesozoic strata are largely absent in New York. Nevertheless, evidence suggests that during the Triassic the geologic forces responsible for the breakup of Pangaea formed rift basins in the state. Dinosaur footprints of the ichnogenus Grallator were left behind to fossilize in what is now Nyack Beach State Park in Rockland County, NY during the Late Triassic. Other kinds of reptiles contemporary with the dinosaurian trackmakers left behind their own footprints to fossilize.

He also denied Marxism's ability to predict the future development of human society, and—unlike many other Marxists—did not consider humanity's progress into pure communism inevitable, instead opining that society could fossilize or become extinct.

Sharks left behind their teeth to fossilize during the Tertiary. During the Oligocene camels were widespread in Texas. Mammals resembling giant pigs were preserved in the Miocene deposits of the Coastal Plain. Camels remained widespread in the state.

Plants in this type of environment rarely fossilize, but their seeds can be carried beyond the species' natural range of distribution. This theory suggests that angiosperms only managed to spread in subtropic lowlands, where they have been found in Early Cretaceous rock.

During the Carboniferous a rich flora developed on land. Primitive tetrapods left behind footprints that would later fossilize. By the end of that period the sea had disappeared from the state. The Permian, Triassic, and Jurassic are missing from the local rock record.

Rifts formed in the state as the supercontinent was being disassembled. Water filled these rifts and created large lakes. Local reptiles would sometimes be preserved in the sediments of these lakes. During the Triassic, local dinosaurs left behind footprints that would later fossilize.

The formation of fossil eggs begins with the original egg itself. Not all eggs that end up fossilizing experience the death of their embryo beforehand. Even eggs that successfully hatch can fossilize. In fact, not only is this possible it's actually common.

During the Late Precambrian, Alaska was covered by a shallow sea. This sea was home to bacteria and stromatolites that would later fossilize. Most of the state continued to be submerged by the sea. By this time Alaska was home to brachiopods and trilobites.

At this time, Oklahoma was home to amphibians, insects, and reptiles. Footprints laid down at this time would later fossilize. Permian Oklahoma was relatively unchanged from its Pennsylvanian state. Contemporary wildlife of Logan, Noble, Grant, and Garfield Counties included branchiopods, insects, and stegocephalian amphibians.

Forty foot Tylosaurus swam over Texas during the Campanian. More sharks left behind their teeth to fossilize during the Late Cretaceous. The terrestrial flora of Late Cretaceous Texas left behind plant fossils in northern Texas. During the early Cenozoic, Texas was the site of significant volcanic eruptions.

Cretaceous marine invertebrate life of Mississippi included cephalopods, coccolithophores, coelenterates, gastropods, the tube-shaped trace fossils Halymenites major, oysters, and scaphopods. Local vertebrates included the Late Cretaceous mosasaur Platecarpus tympaniticus. Sharks also left behind many teeth to fossilize. Cretaceous plant life left behind few fossils in Mississippi.

Since coralline algae contain calcium carbonate, they fossilize fairly well. They are particularly significant as stratigraphic markers in petroleum geology. Coralline rock was used as building stone since the ancient Greek culture. The calcite crystals composing the cell wall are elongated perpendicular to the cell wall.

Large parts consisted of cartilage that did not fossilize. On several occasions the enigmatic large partial remains have been mistaken for stegosaurian dinosaur bones. As the vertebrae are among the parts that have not been preserved, it is hard to determine the total body length. Estimates have varied significantly.

Local dinosaurs left behind footprints that would later fossilize. For the rest of the Mesozoic sea levels in the state would rise and fall. During a dry spell in the Jurassic the state was covered in sand dunes. Later the sea rose and covered much of the state.

The armored fish Palaeaspis appeared during the Silurian. By the Devonian the state was home to other kinds of fishes. On land, some of the world's oldest tetrapods left behind footprints that would later fossilize. Some of Pennsylvania's most important fossil finds were made in the state's Devonian rocks.

Rhinoceroses remained and were a prominent member of Oligocene Nebraska's fauna. Camels were a new arrival to Nebraska during the Oligocene. The earliest known example was Poebrotherium. The Oligocene wildlife of Scotts Bluff National Monument left behind footprints that would later fossilize in the sediments of the Arikaree beds.

Armored and duckbilled dinosaurs inhabited the state, as did tyrannosauroids. The local dinosaurs also left behind eggs to fossilize. During most of the Tertiary period of the Cenozoic southern Alabama was covered by the sea. The rest of the state was a coastal plain covered by subtropical forests.

Local dinosaurs left behind footprints that would later fossilize. During the ensuing Cretaceous period the southern part of New Jersey was submerged under seawater. Invertebrate remains are the state's most common Cretaceous fossils. Invertebrates that lived in New Jersey during the Cretaceous include the oysters Exogyra ponderosa and Gryphaea.

If the conditions are good, chemical gardens can also occur in nature. There is evidence from paleontology, that such chemical gardens may fossilize. Such pseudofossils can be very difficult to distinguish from fossilized organisms. Indeed, some of the earliest purported fossils of life might be fossilized chemical gardens.

Amniota was first formally described by the embryologist Ernst Haeckel in 1866 on the presence of the amnion, hence the name. A problem with this definition is that the trait (apomorphy) in question does not fossilize, and the status of fossil forms has to be inferred from other traits.

Sharks left behind their teeth to fossilize at this time. Vertebrates included fishes and relatives of modern crocodiles called phytosaurs. Triassic fossils were preserved in areas of western Texas like the Glass Mountains as well as the High Plains. The phytosaur fossils were preserved at the edge of the High Plains.

During the Early Cretaceous Texas was home to the pliosaurid Brachauchenius. Western Interior Seaway researcher Michael J. Everhart has called it a "true 'sea monster'" of its time. Sharks left behind their teeth to fossilize during the Early Cretaceous. The Cretaceous sharks of Texas were similar to those of Kansas.

That they were extended by or composed completely of keratin, which does not fossilize easily, had misled earlier research. For Pterorhynchus and Pterodactylus, the true extent of these crests has only been uncovered using ultraviolet photography.Czerkas, S.A., and Ji, Q. (2002). A new rhamphorhynchoid with a headcrest and complex integumentary structures.

Most pathologies preserved in theropod fossils are the remains of injuries, but infections and congenital deformities have also been documented. Pathologies are less frequently documented in small theropods, although this may simply be because the larger bones of correspondingly larger animals would be more likely to fossilize in the first place.

It strengthens blood vessels and plays a role in tissue development. It is present in the cornea and lens of the eye in crystalline form. It may be one of the most abundant proteins in the fossil record, given that it appears to fossilize frequently, even in bones from the Mesozoic and Paleozoic.

During the Triassic, Wyoming's sea continued its withdrawal. As the sea shrunk away, much of Wyoming was occupied by a coastal plain environment divided by rivers. During the Late Triassic, dinosaurs left behind small footprints in western Wyoming that would later fossilize. These tracks have been referred to the ichnospecies Agialopus wyomingensis.

As the Carboniferous progressed vast delta formed beside the sea. The richly vegetated swamps that grew across these deltas in the northwestern part of the state left behind great coal beds. The dense vegetation of these swamps also left behind many fossils. Tetrapods of this age left footprints that would later fossilize.

One approach to understanding overall brain evolution is to use a paleoarchaeological timeline to trace the necessity for ever increasing complexity in structures that allow for chemical and electrical signaling. Because brains and other soft tissues do not fossilize as readily as mineralized tissues, scientists often look to other structures as evidence in the fossil record to get an understanding of brain evolution. This, however, leads to a dilemma as the emergence of organisms with more complex nervous systems with protective bone or other protective tissues that can then readily fossilize occur in the fossil record before evidence for chemical and electrical signaling. Recent evidence has shown that the ability to transmit electrical and chemical signals existed even before more complex multicellular lifeforms.

These swamps were responsible for leaving behind great coal deposits. The local flora also left behind remains that would later fossilize in what are now southern Labette County and Montgomery County. The plant Walchia grew in Anderson County, although its fossils are rare. The contemporary terrestrial environments of Kansas were home to invertebrates like scorpions.

The best source of Mississippian fossils in Oklahoma is the state's northeastern region. During the Carboniferous, Oklahoma was a terrestrial environment characterized by vast river systems and accompanying deltas. These deltas were home to vast swamps responsible for leaving behind many coal deposits. During the Carboniferous, early tetrapods left behind footprints that would later fossilize.

Oklahoma's diverse Pennsylvanian life included blastoids, brachiopods, bryozoans, fusulinids, and pelecypods. Vertebrates included paleoniscid fishes, and the primitive tetrapods responsible for leaving contemporary footprints that would later fossilize. Occasionally during this period, sea levels would rise and cover the state again. This sea gradually retreated from the state before the end of the Paleozoic era.

Only after about 10,000 years will a shark tooth fossilize. The teeth commonly found are not white because they are covered with sediment from fossilization. The sediment prevents oxygen and bacteria from attacking and decaying the tooth. Fossilized shark teeth can often be found in or near river bed banks, sand pits, and beaches.

Does hot water freeze first?. Physics World, pp. 19–26. New Scientist recommends starting the experiment with containers at to maximize the effect.How to Fossilize Your Hamster: And Other Amazing Experiments for the Armchair Scientist, In a related study, it was found that freezer temperature also affects the probability of observing the Mpemba phenomenon as well as container temperature.

These are significant because bird fossils are very rare. Many streams carried even more sediment into the region from the young Rocky Mountains and Black Hills. At the time South Dakota consisted of plains dotted with marshes and shallow lakes and split by wide streams. Some of the local Oligocene wildlife left behind footprints that would later fossilize.

They were also home to amphibians and early reptiles. Such contemporary tetrapods left behind footprints in Kansas that would later fossilize. Among these were tracks of the ichnogenus Limnopus. Other fossils from this time period include Wakarusopus tracks left behind in Douglas County by a colossal amphibian that would have weighed several hundred pounds in life.

During the Carboniferous, an expanse of coastal deltaic swamps formed in areas of the state where early tetrapods would leave behind footprints that would later fossilize. The sea withdrew altogether during the Permian period. Oklahoma was home a variety of insects as well as early amphibians and reptiles. Oklahoma stayed dry for most of the Mesozoic.

The presence of termites in the state at this time is attested to by the existence of a single fossil wing preserved 2.5 miles south of Columbus. The Tertiary marine life of Kentucky included marine mollusks. Fish were also present and sometimes their scales would fossilize. Pliocene to Pleistocene invertebrate fossils are common in Fayette County.

In fact, the Malacostracan has a well-documented fossil record, that, although patchy or missing entirely (ghost lineage) for certain clades, offer a unique opportunity to analyse the morphology of the ancestral taxa of a clade or a dead-end sister taxa (plesion), whose age (determined by its stratigraphy) gives an estimate of how long has a group been around. However, the major limitation to fossilized samples is that typically the soft parts do not fossilize and are therefore lost, as a consequence a much more limited amount of information that can be gathered. Furthermore, some taxa may not fossilize well, and therefore leave no trace even though they existed, when this occurs in the fossil record, the period where the taxa are expected to appear is called a ghost range.

Giant salamander-like amphibians left behind footprints near Lawrence, Kansas that would later fossilize. Fossil footprints from this time period were also preserved in eastern states like Alabama, Georgia, West Virginia, Ohio, and Pennsylvania where Carboniferous fossil footprints are known. alt= The world's continents were joined as Pangaea throughout all of the Permian. Volcanic activity occurred on the west coast.

During the Late Triassic, carnivorous dinosaurs left behind footprints that would later fossilize. During the Cretaceous, however, the state was mostly covered by the Western Interior Seaway, which was home to huge ammonites and other marine invertebrates. During the Cenozoic, Oklahoma became home to creatures like bison, camels, creodonts, and horses. During the Ice Age, the state was home to mammoths and mastodons.

Author Marian Murray described the region as "one of the finest collecting areas in the world for marine life". More than 320 kinds of crinoids are known from the region and more than 50 different kinds of blastoids as well. Sharks left behind their teeth to fossilize during the Permian. Amphibians and reptiles were preserved in Archer and Baylor counties during the Permian.

The fossil record in Montana stretches all the way back to the Precambrian. During the Late Precambrian, western Montana was covered by a warm, shallow sea. This sea was home to stromatolites and to bottom-dwelling marine life whose tracks on the benthic sediment would later fossilize. Montanan life of the time included arthropods, blue-green algae, conularians, fungi, and worms.

The rich flora left abundant plant fossils ranging from microscopic to large logs. Some of the state's early tetrapods left behind footprints that would later fossilize in the vicinity of Kansas City. The sea covering Missouri was gradually filled in by sediments eroded off mountains to the east. Missouri was no longer covered by the sea by the end of the Carboniferous.

This sea withdrew from the state between the Silurian and early Devonian leaving a gap in the local rock record. It returned during the Carboniferous. Areas of the state not submerged were richly vegetated and inhabited by amphibians that left behind footprints that would later fossilize. During the Permian, the sea withdrew and alluvial fans and sand dunes spread across the state.

Mountain ranges were being raised in the western part of the state by geologic forces. During the Carboniferous, footprints were laid down in Colorado by early tetrapods that would later fossilize. That being said, Colorado is not generally a good source of Carboniferous aged fossils. Western Colorado had a series of alluvial fans during the Permian when the Cutler Group was being deposited.

Lambdopsalis bulla is an extinct multituberculate mammal from the Late Paleocene of China and Mongolia. It is placed within the suborder Cimolodonta and is a member of the superfamily Taeniolabidoidea. Fossil remains have been found in the Late Paleocene Nomogen and Khashat Formations in Nao-mugen and Bayn Ulan of China and Mongolia. Hair and fur fossilize very infrequently, if at all.

Nevertheless, the fossil record of cephalopod eggs is scant since their soft, gelatinous eggs decompose quickly and have little chance to fossilize. Another major group of Mesozoic cephalopods, the belemnoids, have no documented eggs in the fossil record whatsoever, although this may be because scientists have not properly searched for them rather than an actual absence from the fossil record.

Aspidella consists of disk- shaped fossils, with concentric rings and/or centripetal rays. The diameter of circular Aspidella varies from 1 to 180 mm.Peterson. P. 131 Most individuals are between 4 and 10 mm, but smaller individuals would presumably have decayed before they could fossilize. Other Aspidella take the form of ellipses, 3–8 cm long and 1–4 cm wide.

The highest aspect ratio eumelanosomes were found in a sample from the head feathers. High aspect ratios have been known to correlate with glossy or iridescent colors, although without knowing the structure of a feather's keratin layer (which does not fossilize well), no hue can be assigned for certain. The wing and tail samples also had high aspect ratios, while the tail's eumelanosomes were the largest sampled.

For intervals of time during the Cretaceous the state was once more submerged under seawater. Local oysters left behind remains that would later fossilize. Areas of the state not submerged by the sea were home to dinosaurs. About 75 million years ago, during the Cretaceous, the Black Creek Formation (more properly called the Donoho Creek Formation) was being laid down in southern North Carolina.

A wide variety of vegetation, invertebrates and reptiles are known from Triassic Connecticut. During the Early Jurassic local dinosaurs left behind an abundance of footprints that would later fossilize. The first scientifically verified dinosaur bones discovered in North America were uncovered during the 1818 excavation of a well in Connecticut. Other notable finds include the aetosaur Stegomus, the phytosaur Clepsysaurus, and the prosauropod dinosaur Anchisaurus.

Aphids, and the closely related adelgids and phylloxerans, probably evolved from a common ancestor some , in the Early Permian period. They probably fed on plants like Cordaitales or Cycadophyta. With their soft bodies, aphids do not fossilize well, and the oldest known fossil is of the species Triassoaphis cubitus from the Triassic. They do however sometimes get stuck in plant exudates which solidify into amber.

Tullimonstrum gregarium in a concretion from the Mazon Creek lagerstätten. The Mazon Creek fossil beds are a conservation ' found near Morris, in Grundy County, Illinois. The fossils are preserved in ironstone concretions, formed approximately in the mid-Pennsylvanian epoch of the Carboniferous period. These concretions frequently preserve both hard and soft tissues of animal and plant materials, as well as many soft-bodied organisms that do not normally fossilize.

Due to their soft bodies, chaetognaths fossilize poorly. Even so, several fossil chaetognath species have been described. Chaetognaths appear to have originated in the Cambrian Period. Complete body fossils have been formally described from the Lower Cambrian Maotianshan shales of Yunnan, China (Eognathacantha ercainella Chen & Huang and Protosagitta spinosa Hu) and the Middle Cambrian Burgess Shale of British Columbia (Oesia disjuncta Walcott), a view challenged by Conway Morris (2009).

During the Carboniferous local sea levels dropped and a vast complex of richly vegetated delta formed in the state. These swampy deltas were home to early tetrapods which left behind footprints that would later fossilize. Little is known of Triassic Georgia and the Jurassic is absent altogether from the state's rock record. During the Cretaceous, however, southern Georgia was covered by a sea that was home to invertebrates and fishes.

Viruses co-exist with life wherever it occurs. They have probably existed since living cells first evolved. Their origin remains unclear because they do not fossilize, so molecular techniques have been the best way to hypothesise about how they arose. These techniques rely on the availability of ancient viral DNA or RNA, but most viruses that have been preserved and stored in laboratories are less than 90 years old.

The ensuing Triassic period of the Mesozoic era is missing from the state's rock record for the same reason as the Permian. During the Jurassic, local plants left behind spores that would later fossilize. However, these are the only known local fossil from the time period since rocks of this age are buried deep underground and accessible only through core sample drilling. Like the Permian and Triassic, Cretaceous rocks are altogether absent from the state.

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.

An interlanguage is an idiolect that has been developed by a learner of a second language (or L2) which preserves some features of their first language (or L1), and can also overgeneralize some L2 writing and speaking rules. These two characteristics of an interlanguage result in the system's unique linguistic organization. An interlanguage is idiosyncratically based on the learners' experiences with the L2. It can "fossilize", or cease developing, in any of its developmental stages.

The limestone laid down around Alpena comes from the Devonian Period, the 4th period of the Paleozoic Era (roughly 416-358 million years ago) the "Age of the Fishes". Marine life was intensely diverse, before formation of the supercontinent of Pangaea, when 85% of the earth's surface was oceans. Fish of this period were cartilaginous, mainly shark ancestors. Cartilage does not fossilize, so fossils from the area are typically be from "filter feeding" creatures.

With their soft bodies, earthworms do not fossilize well, though they may form trace fossils. The name Protoscolex was given to a genus of segmented worms without bristles found in the Upper Ordovician of Kentucky, United States. Another species placed in the same genus was found in Herefordshire, England, but it is unclear whether these worms are in fact oligochaetes. Stephenson postulated in 1930 that the common ancestor of oligochaetes came from the primitive aquatic family Lumbriculidae.

Three principal sources exist for comparative evolutionary investigations: Fossils, fresh-preserved post-mortem or in vivo studies. The fossil record is dominated by structures that were already biomineralized during the lifetime of the respective organism (in the case of vertebrates, mainly teeth and bones). Brains, like other soft tissues, rarely fossilize, but occasionally they do. The probably oldest vertebrate brain known today belonged to a ratfish that lived around 300 million years ago (Pradel et al.

The state's Paleozoic seas would come to be home to creatures like brachiopods, fishes, and trilobites. During the Permian the state came to resemble the Sahara desert and was home to amphibians, early relatives of mammals, and reptiles. During the Triassic about half of the state was covered by a sea home to creatures like the cephalopod Meekoceras, while dinosaurs whose footprints would later fossilize roamed the forests on land. Sand dunes returned during the Early Jurassic.

The fossil Charniodiscus is barely distinguishable from the "elephant skin" texture on this cast. All but the smallest fraction of the fossil record consists of the robust skeletal matter of decayed corpses. Hence, since Ediacaran biota had soft bodies and no skeletons, their abundant preservation is surprising. The absence of burrowing creatures living in the sediments undoubtedly helped; since after the evolution of these organisms in the Cambrian, soft-bodied impressions were usually disturbed before they could fossilize.

At the end of the process, LECA was already a complex organism with the presence of protein families involved in cellular compartmentalization. Elucidation of this problem from paleontological record is hindered due to taphonomic loss of biomarkers and the small likelihood that cells without walls or other coverings fossilize. This taphonomic barrier blurs our view of the FECA-LECA transition. The recognition of early eukaryotes lies on general eukaryotic features: larger size, morphological complexity and multicellularity.

Possible Aulacostephanus eggs have been reported from the Kimmeridge Clay of England Cephalopod egg fossils are the fossilized remains of eggs laid by cephalopods. The fossil record of cephalopod eggs is scant since their soft, gelatinous eggs decompose quickly and have little chance to fossilize. Eggs laid by ammonoids are the best known and only a few putative examples of these have been discovered. The best preserved of these were discovered in the Jurassic Kimmeridge Clay of England.

An interlanguage can fossilize, or cease developing, in any of its developmental stages. Fossilization is the process of 'freezing' of the transition between the L1 and L2, and is regarded as the final stage of interlanguage development. It can occur even in motivated learners who are continuously exposed to their L2 or have adequate learning support. Reasons for this phenomenon may be due to complacency or inability to overcome the obstacles to acquiring native proficiency in the L2.

Bones on the left side of the skull were displaced as the animal decayed, but the majority of the right side was able to fossilize. Most of the actual fossilized bones had been eroded away once the specimen was found, although well-preserved molds were left behind in the sandstone. Currie's description was based on latex casts made from the molds. During a 2009 redescription by Constanze Bickelmann, Johannes Mueller, & Robert R. Reisz, new high-fidelity latex molds were created using improved techniques.

This sea remained in place during the early Paleozoic era and would come to be inhabited by creatures like brachiopods, ostracoderms, and trilobites. During the Silurian, the sea withdrew from Wyoming and there is a gap in the local rock record. During the Devonian the sea returned to the state and remained until the Permian when it started to withdraw once more. By the Triassic the state had become a coastal plain inhabited by dinosaurs whose footprints would later fossilize.

Also like the Carboniferous, despite the presence of contemporary trace fossils, the fossil record of Permian life in Colorado is relatively poor compared to states like Kansas and Texas. Allosaurus. Diplodocus. Seawater returned to Colorado during the ensuing Triassic period, although it left significant areas of the state uncovered. These terrestrial areas included coastal floodplains vegetated by conifers and inhabited by creatures like amphibians and dinosaurs. The Late Triassic also saw the formation of many footprints that would later fossilize.

Vertebrae from other sections of the tail were found. Although the tip of the tail did not fossilize, some of the smaller vertebrae recovered would have been situated near the end of the tail in life, and these were associated with ossified tendons on the upper and lower sides. In ankylosaurids, these tendons help to stiffen the end of the tail in support of a large, bony tail club. If such a club existed in Antarctopelta, it has yet to be discovered.

In large enough quantities, gastropod shells can have enough of an impact on environmental conditions to affect the ability of organic remains in the local environment to fossilize. For example, in the Dinosaur Park Formation, fossil hadrosaur eggshell is rare. This is because the breakdown of tannins from local coniferous vegetation would have caused the ancient waters to become acidic. Eggshell fragments are present in only two microfossil sites, both of which are predominated by the preserved shells of invertebrate life, including gastropods.

The fossil Charniodiscus is barely distinguishable from the "elephant skin" texture on this cast. The preservation of these fossils is one of their great fascinations to science. As soft-bodied organisms, they would normally not fossilize and, unlike later soft-bodied fossil biota such as the Burgess Shale or Solnhofen Limestone, the Ediacaran biota is not found in a restricted environment subject to unusual local conditions: they were a global phenomenon. The processes that were operating must have been systemic and worldwide.

Although the size of these mammals is believed to be larger because the cartilage is not being accounted for when they fossilize. Until recently, how many species of Diprotodon had existed was unknown. Eight species are described, although many researchers believed these actually represented only three at most, while some estimated about 20 in total could exist. John Walter Gregory collected stories of mystical creatures in Aboriginal myths and legends and considered the possible connections between them and extinct species.

A hammerhead shark gliding along the sea bed Since sharks do not have mineralized bones and rarely fossilize, their teeth alone are commonly found as fossils. The hammerheads seem closely related to the carcharhinid sharks that evolved during the mid-Tertiary period. According to DNA studies, the ancestor of the hammerheads probably lived in the Miocene epoch about 20 million years ago. Using mitochondrial DNA, a phylogenetic tree of the hammerhead sharks showed the winghead shark as its most basal member.

Only the rarer species among modern mammal communities would be able to distinguish different latitudinal zones, and some of these taxa are likely too rare to fossilize. This lack of provinciality exists despite the strong temperature gradient. Restrictions in herbivorous dinosaur distribution may be due to foliage preferences, narrow tolerance for variation in climate or other environmental factors. The restrictions on herbivorous dinosaur distribution must have been due to ecological factors rather than physical barriers because carnivorous dinosaurs tended to have wider distributions, especially smaller forms.

Contemporaries of Limusaurus in the Wucaiwan locality include the theropods Haplocheirus, Zuolong, Guanlong, Aorun, and Shishugounykus; the sauropod Mamenchisaurus; the ornithischians Gongbusaurus, Yinlong, and Hualianceratops; the cynodont Yuanotherium; the mammal Acuodulodon; the crocodyliform Nominosuchus and another unnamed crocodyliform found with the holotype specimen of Limusaurus; and the turtles Xinjiangchelys and Annemys. Small theropod dinosaurs are generally rare in the fossil record. According to Eberth and colleagues, the high incidence of Limusaurus indicates that the abundance of small theropods is underestimated elsewhere as these animals are generally less likely to fossilize.

Bottosaurus had distinctively thick osteoderms that lacked the pitting of most other crocodylians. The unusual blunt, conical tribodontid crushing teeth are the most common diagnostic material to fossilize and be recovered, although teeth from the posterior portion of the jaw tend to be more laterally compressed like those of other related crocodiles. The teeth had a "wrinkled" enamel surface and prominent annual rings with vertical ridges running down them. A short, massive lower jaw that is nearly circular in cross-section is evident from remains of the type species B. harlani.

The location of the state of Montana Paleontology in Montana refers to paleontological research occurring within or conducted by people from the U.S. state of Montana. The fossil record in Montana stretches all the way back to the Precambrian. During the Late Precambrian, western Montana was covered by a warm, shallow sea where local bacteria formed stromatolites and bottom- dwelling marine life left tracks on the sediment that would later fossilize. This sea remained in place during the early Paleozoic, although withdrew during the Silurian and Early Devonian, leaving a gap in the local rock record until its return.

Not long after, fossil Iguanodon footprints were discovered in Sussex, England, a discovery that probably served as the inspiration for Sir Arthur Conan Doyle's The Lost World. Several enduring mysteries from the 19th century continued to vex ichnologists, like the identity of the Chirotherium trackmaker. Renowned paleontologist Franz von Nopcsa attributed the ichnogenus to the prosauropod dinosaur Plateosaurus, despite an apparent mismatch between its number of toes (4) and the preserved digit traces of Chirotherium (5). Von Nopcsa explained the discrepancy by arguing that one of the impressions in the Chirotherium tracks was left by a soft tissue structure that did not fossilize.

Lonchodytes is a Late Cretaceous genus of aquatic bird, which lived along the shores of the Western Interior Seaway. It lived probably during the Maastrichtian, 70 million years ago (mya), and was found in Lance Creek Formation rocks in Wyoming (United States) though it seems still somewhat unclear if it did fossilize there or was reworked from later (Danian: Early Paleocene, less than 65 mya) deposits. Lonchodytes estesi, the type species, appears to be closely related to the ancestor of some modern birds. It is most often allied - albeit tentatively - with the Gaviiformes (loons/divers), Procellariiformes (tubenoses) or Pelecaniformes.

This first specimen is the holotype: MFSN-1770. A second, disarticulated specimen, MFSN-1891, was found at the same locale in 1984 about 150–200 meters (490–650 ft) deeper into the strata than the original find. The second specimen appears to have been preserved in the gastric pellet of a predatory fish, which had consumed the pterosaur and vomited up the indigestible pieces that would later fossilize. More detailed knowledge of the variability of Triassic pterosaurs has made the identification of this specimen as Preondactylus uncertain, and it may even be that the remains are not those of a pterosaur at all.

In large enough quantities, unionid shells can have enough of an impact on environmental conditions to affect the ability of organic remains in the local environment to fossilize. For example, in the Dinosaur Park Formation, fossil hadrosaur eggshell is rare because the breakdown of tannins from local coniferous vegetation would have caused the ancient waters to become acidic. Eggshell fragments are present in only two microfossil sites, both of which are dominated by the preserved shells of invertebrate life, including unionids. The slow dissolution of these shells releasing calcium carbonate into the water raised the water's pH high enough to prevent the eggshell fragments from dissolving before they could be fossilized.

Although cartilaginous skeletons do not fossilize, O. megalodon is estimated to have been considerably larger than the great white shark, estimated at up to . Similarities among the physical remains and the extreme size of both the great white and O. megalodon led many scientists to believe these sharks were closely related, and the name Carcharodon megalodon was applied to the latter. However, a new hypothesis proposes that the great white is also more closely related to an ancient mako shark, Isurus hastalis, than to the O. megalodon. The theory seems to be supported with the earlier discovery of a complete set of jaws with 222 teeth and 45 vertebrae of the extinct transitional species Carcharodon hubbelli in 1988.

The independent origins of this trait are further supported by crystallographic differences between clades: the orientation of the axes of the deposited aragonite 'bricks' that make up the nacreous layer is different in each of the monoplacophora, gastropods and bivalves. Mollusc shells (especially those formed by marine species) are very durable and outlast the otherwise soft- bodied animals that produce them by a very long time (sometimes thousands of years even without being fossilized). Most shells of marine molluscs fossilize rather easily, and fossil mollusc shells date all the way back to the Cambrian period. Large amounts of shell sometimes forms sediment, and over a geological time span can become compressed into limestone deposits.

Fossils of Atlanticopristis were discovered in the Maranhão state of northeastern Brazil, at the Alcântara Formation of the Itapecuru Group on Cajual Island. The formation, composed of Cretaceous sediments, outcrops at the coastline of the Sao Marcos Bay, and documents the separation of South America and Africa; while presenting a large quantity and variety of continental and marine vertebrates. Fossils from the Alcântara Formation are highly diverse and plentiful, yet often fragmentary. Fourteen rostral teeth from Atlanticopriostis were brought back from the Falésia do Sismito exposure; due to the fact that sawfish are made of cartilage, their skeletons do not fossilize easily, so most remains found consist of the teeth from their snouts.

Because many characters involve embryological, or soft-tissue or molecular characters that (at best) hardly ever fossilize, and the interpretation of fossils is more ambiguous than that of living taxa, extinct taxa almost invariably have higher proportions of missing data than living ones. However, despite these limitations, the inclusion of fossils is invaluable, as they can provide information in sparse areas of trees, breaking up long branches and constraining intermediate character states; thus, fossil taxa contribute as much to tree resolution as modern taxa. Fossils can also constrain the age of lineages and thus demonstrate how consistent a tree is with the stratigraphic record; stratocladistics incorporates age information into data matrices for phylogenetic analyses.

Jamoytius kerwoodi, a putative lamprey relative from the Silurian Mayomyzon, one of the oldest known lampreys Lamprey fossils are rare because cartilage does not fossilize as readily as bone. The first fossil lampreys were originally found in Early Carboniferous limestones, marine sediments in North America: Mayomyzon pieckoensis and Hardistiella montanensis, from the Mississippian Mazon Creek lagerstätte and the Bear Gulch limestone sequence. None of the fossil lampreys found to date have been longer than 10 cm (3,9 inches), and all the Paleozoic forms have been found in marine deposits. In the 22 June 2006 issue of Nature, Mee-mann Chang and colleagues reported on a fossil lamprey from the Yixian Formation of Inner Mongolia.

The Stand also enables Valentine to summon others from alternate realities, though only he and his counterparts are immune to the usual demise of two iterations of the same person annihilating each other in the form of Menger sponges upon physical contact. ; :Diego Brando, nicknamed , is a British racer in the Steel Ball Run, riding the horse . He is initially just a rival to Gyro and Johnny, but allies himself with Valentine and grows to hate them. After being subject to the Stand of Dr. Ferdinand, Diego acquires one of the Saint Corpse's eyes and obtains the Stand , allowing him to transform into a dinosaur at will, as well as transform other living beings into dinosaurs or fossilize them.

Another example is Pentaceratops, the only known Judithian ceratopsian from New Mexico. In modern North America if one was to sample hypothetical future sites in southwestern Texas, northern New Mexico and southern Alberta, 34 of the 41 large mammal species in the continent could be represented, with the remainder's geographic ranges not overlapping with the sites. Roughly 20 species would be located at each site, but contrasting with the provinciality of dinosaurs, 11-16 species out of twenty would be shared between all three sites. Only the rarer species among modern mammal communities would be able to distinguish different latitudinal zones, and some of these taxa are likely too rare to fossilize.

In it, he shows clips from German TV and humorously comments on them or parodies them. In 1996 he was awarded the Adolf-Grimme- Preis for the show. After changing channels several times over the years, the show's current incarnation (entitled Kalkofes Mattscheibe Rekalked) is broadcast on Tele 5. At least since the beginning of the Mattscheibe show, it's Kalkofe trademark to use many various humorous pseudonyms and puns based upon his real last name often mispronounced or misremembered by people and the fact that it involves the syllable Kalk, which is the German word for "chalk" or "lime", and at times these puns also show conscious interplay with the German verb verkalken ("to calcify", "to fossilize", "to ossify", "being a fossil").

The oldest metatherian fossils are found in present-day China. About 100 mya, the supercontinent Pangaea was in the process of splitting into the northern continent Laurasia and the southern continent Gondwana, with what would become China and Australia already separated by the Tethys Ocean. From there, metatherians spread westward into modern North America (still attached to Eurasia), where the earliest true marsupials are found. Marsupials are difficult to distinguish from other fossils, as they are characterized by aspects of the reproductive system which do not normally fossilize (including pouches) and by subtle changes in the bone and tooth structure that show a metatherian is part of the marsupial crown group (the most exclusive group that contains all living marsupials).

Finally, insects (most of which fly at some point in their life cycle) have more species than all other animal groups combined. The evolution of flight is one of the most striking and demanding in animal evolution, and has attracted the attention of many prominent scientists and generated many theories. Additionally, because flying animals tend to be small and have a low mass (both of which increase the surface-area-to-mass ratio), they tend to fossilize infrequently and poorly compared to the larger, heavier-boned terrestrial species they share habitat with. Fossils of flying animals tend to be confined to exceptional fossil deposits formed under highly specific circumstances, resulting in a generally poor fossil record, and a particular lack of transitional forms.

Acantharian skeletons are composed of strontium sulfate crystals secreted by vacuoles surrounding each spicule or spine. Acantharians are the only marine organisms known to biomineralize strontium sulfate as the main component of their skeletons, making them unique. Unlike other radiolarians, whose skeletons are made of silica, acantharian skeletons do not fossilize, primarily because strontium sulfate is very scarce in seawater and the crystals dissolve after the acantharians die. The arrangement of the spines is very precise, and is described by what is called the Müllerian law, which can be described in terms of lines of latitude and longitude – the spines lie on the intersections between five of the former, symmetric about an equator, and eight of the latter, spaced uniformly.

From there, metatherians spread westward into modern North America (still attached to Eurasia), where the earliest true marsupials are found. It is difficult to identify which fossils are marsupials, as they are characterized by aspects of the reproductive system that do not normally fossilize (such as pouches) and by subtle changes in the bone and tooth structure that show a metatherian is part of the marsupial crown group (the most exclusive group that contains all living marsupials). The earliest definite marsupial fossil belongs to the species Peradectes minor, from the Paleocene of Montana, dated to about 65 million years ago. From this point of origin in Laurasia, marsupials spread to South America, which was connected to North America until around 65 mya.

Early Paleozoic radiolarian fossil history is dominated by Spumellaria until the Carboniferous period, during which nassellarian fauna experienced a sharp increase in diversity. Nassellarian and spumellarian diversities have been relatively similar since the Mesozoic, with drops in diversity after mass extinction events and a rise in both spumellarian and nassellarian diversity during the Quaternary. Symbioses between algae and radiolarians is observed frequently in extant species, but the evolution and timing of this symbiosis is currently unknown, as the symbiotic algae do not leave behind hard skeletons to fossilize. It may be possible to answer this question using isotopic analysis, as algal symbionts preferentially uptake carbon-12, so symbiont-bearing calcareous organisms such as Foraminifera become enriched in carbon-13 compared to non symbiont-bearing calcareous organisms.

Some of the most remarkable gaps in the fossil record (as of October 2013) show slanting toward organisms with hard parts. Organisms are only rarely preserved as fossils in the best of circumstances, and only a fraction of such fossils have been discovered. This is illustrated by the fact that the number of species known through the fossil record is less than 5% of the number of known living species, suggesting that the number of species known through fossils must be far less than 1% of all the species that have ever lived. Because of the specialized and rare circumstances required for a biological structure to fossilize, only a small percentage of life-forms can be expected to be represented in discoveries, and each discovery represents only a snapshot of the process of evolution.

A patch of pennaceous feathers is found running along its back, which was quite similar to the contour feathers of the body plumage of modern birds in being symmetrical and firm, although not as stiff as the flight-related feathers. Apart from that, the feather traces in the Berlin specimen are limited to a sort of "proto-down" not dissimilar to that found in the dinosaur Sinosauropteryx: decomposed and fluffy, and possibly even appearing more like fur than feathers in life (although not in their microscopic structure). These occur on the remainder of the body—although some feathers did not fossilize and others were obliterated during preparation, leaving bare patches on specimens—and the lower neck. There is no indication of feathering on the upper neck and head.

Not every transitional form appears in the fossil record, because the fossil record is not complete. Organisms are only rarely preserved as fossils in the best of circumstances, and only a fraction of such fossils have been discovered. Paleontologist Donald Prothero noted that this is illustrated by the fact that the number of species known through the fossil record was less than 5% of the number of known living species, suggesting that the number of species known through fossils must be far less than 1% of all the species that have ever lived. Because of the specialized and rare circumstances required for a biological structure to fossilize, logic dictates that known fossils represent only a small percentage of all life-forms that ever existed—and that each discovery represents only a snapshot of evolution.

The good language learner (GLL) studies are a group of academic studies in the area of second language acquisition that deal with the strategies that good language learners exhibit. The rationale for the studies was that there is more benefit from studying the habits of successful language learners than there is from studying learners who fossilize at an early stage or stop studying altogether. It was thought that if the strategies of successful learners could be found, then that knowledge could help learners who were not getting such good results.. The original studies were made in the 1970s, but petered out in the 1980s as researchers concentrated on individual learning strategies. However, some research on the topic has also been carried out in more recent years... The main body of GLL research investigated language learning in classroom situations.

Map showing where Ankylosaurus fossils have been discovered; the holotype is shown in red (◆) Ankylosaurus existed between 68 and 66 million years ago, in the final, or Maastrichtian, stage of the Late Cretaceous Period. It was among the last dinosaur genera that appeared before the Cretaceous–Paleogene extinction event. The type specimen is from the Hell Creek Formation of Montana, while other specimens have been found in the Lance and Ferris Formations in Wyoming, the Scollard Formation in Alberta, and the Frenchman Formation in Saskatchewan, all of which date to the end of the Cretaceous. Fossils of Ankylosaurus are rare in these sediments, and the distribution of its remains suggests that it was ecologically rare, or restricted to the uplands of the formations rather than the coastal lowlands, where it would have been more likely to fossilize.

Westlothiana, a small reptile-like tetrapod which may be an early lepospondyl, close to the origin of amniotes, or both Exactly where the border between reptile-like amphibians (non-amniote reptiliomorphs) and amniotes lies will probably never be known, as the reproductive structures involved fossilize poorly, but various small, advanced reptiliomorphs have been suggested as the first true amniotes, including Solenodonsaurus, Casineria and Westlothiana. Such small animals laid small eggs, 1 cm in diameter or less. Small eggs would have a small enough volume to surface ratio to be able to develop on land without the amnion and chorion actively effecting gas exchange, setting the stage for the evolution of true amniotic eggs. Although the first true amniotes probably appeared as early as the Middle Mississippian sub-epoch, non-amniote (or amphibian) reptiliomorph lineages coexisted alongside their amniote descendants for many millions of years.

In line with this classification they interpreted the dark patches round the foot as gill-like ctenidia, another feature of some molluscs; and the sediment that sometimes appeared in the fossils between the foot and supposed ctenidia suggested the presence of a mantle cavity. They also concluded that Odontogriphus was closely related to the Ediacaran animal Kimberella, whose fossils also show signs of a fairly rigid upper "shell" made of a material that did not fossilize, and which has been interpreted as a very mollusc-like organism. They went on to classify the halkieriids as nearly modern molluscs, since in their opinion halkieriids' "chain mail" coats of mineralized sclerites were an advance on the unmineralized sclerites of Wiwaxia and also resembled the armor of some living shell-less aplacophoran molluscs, the Neomeniomorpha. As a result, they concluded that the whole Kimberella-Odontogriphus-Wiwaxia-mollusc lineage must have diverged from that of the annelid worms some time before the appearance of Kimberella in the Ediacaran period.