Owen R. 1846. Report on the archetype and homologies of the vertebrate skeleton. British Association. The weak point in Owen's theory was its basis solely on the more derived and specialised skulls, and even so it took no notice of their embryological development.
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Later in life a State pension was awarded. The honours and appointments Parker gained later in life were due mainly for his work on the vertebrate skeleton and its significance in establishing a "true theory of the vertebrate skull" (Edward Sabine). His Royal Society obituary notice described him as "An unworldly seeker after truth, loved by all who knew him".Jones T. Rupert and Harting J.E. 1900.
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Owen with his granddaughter Emily Owen's detailed memoirs and descriptions require laborious attention in reading, on account of their complex terminology and ambiguous modes of expression. The fact that very little of his terminology has found universal favour causes them to be more generally neglected than they otherwise would be. At the same time, it must be remembered that he was a pioneer in concise anatomical nomenclature and, so far at least as the vertebrate skeleton is concerned, his terms were based on a carefully reasoned philosophical scheme, which first clearly distinguished between the now- familiar phenomena of analogy and homology. Owen's theory of the Archetype and Homologies of the Vertebrate Skeleton (1848), subsequently illustrated also by his little work On the Nature of Limbs (1849), regarded the vertebrate frame as consisting of a series of fundamentally identical segments, each modified according to its position and functions.
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A bone is a rigid organ that constitutes part of the vertebrate skeleton in animals. Bones protect the various organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, and enable mobility. Bones come in a variety of shapes and sizes and have a complex internal and external structure. They are lightweight yet strong and hard, and serve multiple functions.
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The longer element ( long) is not developed enough to identify, but may be a tibia. The taxonomic identity of the embryo is impossible to determine, but based on comparisons to Troodon, Orodromeus, and Maiasaura, it is estimated to have been long. It clearly represents a very early stage of development (in fact, it is the youngest vertebrate skeleton ever discovered), both because of the lack of ossification and because of its tiny size relative to the egg; based on comparisons to the developmental patterns of modern birds, Horner (1997) estimated it may have died eight to ten days after fertilization.
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Featured in the Time 100 list of most influential people, Mukherjee writes for The New Yorker and is a columnist in The New York Times. He is described as part of a select group of doctor-writers (such as Oliver Sacks and Atul Gawande) who have "transformed the public discourse on human health", and allowed a generation of readers a rare and intimate glimpse into the life of science and medicine. His research concerns the physiology of cancer cells, immunological therapy for blood cancers, and the discovery of bone- and cartilage-forming stem cells in the vertebrate skeleton. The Government of India conferred on him its fourth highest civilian award, the Padma Shri, in 2014.
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A dermal bone or investing bone or membrane bone is a bony structure derived from intramembranous ossification forming components of the vertebrate skeleton including much of the skull, jaws, gill covers, shoulder girdle and fin spines rays (lepidotrichia), and the shell (of tortoises and turtles). In contrast to endochondral bone, dermal bone does not form from cartilage that then calcifies, and it is often ornamented. Dermal bone is formed within the dermis and grows by accretion only – the outer portion of the bone is deposited by osteoblasts. The function of some dermal bone is conserved throughout vertebrates, although there is variation in shape and in the number of bones in the skull roof and postcranial structures.
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Huxley was the first man to attack Owen's ideas on the vertebrate skeleton, in his Croonian Lecture to the Royal Society in 1858. He showed from a study of the early stages of lower fish, and also the stickleback and the frog, that the segmentation of the skull in higher vertebrata is a secondary process, and is independent of vertebration. The basis of the work was embryology, but the early history of the skull was known in only a few species. Parker's distinction was to carry out a careful study of the process in a much wider variety of vertebrates; his ironic comment on the "anatomical suffering caused to fish from their being dragged into harmony with that mischievous piece of work, the vertebrate archetype" shows, from such a gentle man, a surprising vigour in debate.
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" From the earliest to the latest of Oken's writings on the subject, "the head is a repetition of the whole trunk with all its systems: the brain is the spinal cord; the cranium is the vertebral column; the mouth is intestine and abdomen; the nose is the lungs and thorax; the jaws are the limbs; and the teeth the claws or nails." Johann von Spix (1781–1826) in his folio Cephalogenesis (1818), richly illustrated comparative craniology, but presented the facts under the same transcendental guise; and Georges Cuvier (1769–1832) availed himself of the extravagances of these disciples of Schelling to cast ridicule on the whole inquiry into those higher relations of parts to the archetype which Sir Richard Owen (1804–1892) called "general homologies." The vertebral theory of the skull had practically disappeared from anatomical science when the labours of Cuvier drew to their close. In Owen's Archetype and Homologies of the Vertebrate Skeleton the idea was not only revived but worked out for the first time inductively, and the theory rightly stated, as follows: "The head is not a virtual equivalent of the trunk, but is only a portion, i.e.
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