| rdfs:comment | - Despite integumentary structures being limited to non-avian dinosaurs, particularly well-documented in maniraptoriformes, fossils do suggest that a large number of theropods were feathered, and it has even been suggested that based on phylogenetic analyses, Tyrannosaurus at one stage of its life may have been covered in down-like feathers, although there is no direct fossil evidence of this. Based on what is known of the dinosaur fossil record, paleontologists generally think that most of dinosaur evolution happened at relatively large body size (a mass greater than a few kilograms), and in animals that were entirely terrestrial. Small size (<1 kg) and arboreal habits seem to have arisen fairly late during dinosaurian evolution, and only within maniraptora.
- Feathered dinosaurs are hypothetical assumptions by evolutionists that are the "missing links" between birds and reptiles. Due to the alleged similarities between the two classes, many scientists assume that the two are related and one must have evolved from the other. However, there is one large problem with this assumption. First of all, there is no way for feathers to have evolved from scales. Evolutionary scientists have tried to prove that feathers could evolve from scales, but the experiments have mostly failed and even if they had worked, the method of implanting the information for feathers on reptile scales proves nothing, because the information was placed there by human intelligence, it did not "evolve" by chance. Second, many evolutionary scientists are now disputing whether or
- Shortly after the 1859 publication of Charles Darwin's The Origin of Species, British biologist and evolution-defender Thomas Henry Huxley proposed that birds were descendants of dinosaurs. He cited skeletal similarities, particularly among some saurischian dinosaurs, fossils of the 'first bird' Archaeopteryx and modern birds. In 1868 he published On the Animals which are Most Nearly Intermediate between Birds and Reptiles, making the case. The leading dinosaur expert of the time, Richard Owen, disagreed, claiming Archaeopteryx as the first bird outside dinosaur lineage. For the next century, claims that birds were dinosaur descendants faded, with more popular bird-ancestry hypotheses including 'crocodylomorph' and 'thecodont"'ancestors, rather than dinosaurs or other archosaurs.
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| abstract | - Feathered dinosaurs are hypothetical assumptions by evolutionists that are the "missing links" between birds and reptiles. Due to the alleged similarities between the two classes, many scientists assume that the two are related and one must have evolved from the other. However, there is one large problem with this assumption. First of all, there is no way for feathers to have evolved from scales. Evolutionary scientists have tried to prove that feathers could evolve from scales, but the experiments have mostly failed and even if they had worked, the method of implanting the information for feathers on reptile scales proves nothing, because the information was placed there by human intelligence, it did not "evolve" by chance. Second, many evolutionary scientists are now disputing whether or not the supposed "feathered dinosaurs" were actually true birds. Since Archaeopteryx was simply discovered to be a bird, it is just as likely that many of these fossils are really just misidentified birds. Third, the archaeoraptor hoax speaks a lot about the possibility of yet more hoaxes. Although the archaeoraptor was discovered by evolutionists to be a hoax within the course of three months, it remains a distinct possiblity that there are other, more elaborate hoaxes that manage to escape the eyes of modern methods of discovering a fraud.
- Despite integumentary structures being limited to non-avian dinosaurs, particularly well-documented in maniraptoriformes, fossils do suggest that a large number of theropods were feathered, and it has even been suggested that based on phylogenetic analyses, Tyrannosaurus at one stage of its life may have been covered in down-like feathers, although there is no direct fossil evidence of this. Based on what is known of the dinosaur fossil record, paleontologists generally think that most of dinosaur evolution happened at relatively large body size (a mass greater than a few kilograms), and in animals that were entirely terrestrial. Small size (<1 kg) and arboreal habits seem to have arisen fairly late during dinosaurian evolution, and only within maniraptora. Birds were originally linked with other dinosaurs back in the late 1800s, most famously by Thomas Huxley. This view remained fairly popular until the 1920s when Gerhard Heilmann's book The Origin of Birds was published in English. Heilmann argued that birds could not have descended from dinosaurs (predominantly because dinosaurs lacked clavicles, or so he thought), and he therefore favored the idea that birds originated from the so-called 'pseudosuchians': primitive archosaurs that were also thought ancestral to dinosaurs and crocodilians. This became the mainstream view until the 1970s, when a new look at the anatomical evidence (combined with new data from maniraptoran theropods) led John Ostrom to successfully resurrect the dinosaur hypothesis. Fossils of Archaeopteryx include well-preserved feathers, but it was not until the early 1990s that clearly nonavian dinosaur fossils were discovered with preserved feathers. Today there are more than twenty genera of dinosaurs with fossil feathers, nearly all of which are theropods. Most are from the Yixian Formation in China. The fossil feathers of one specimen, Shuvuuia deserti, have even tested positive for beta-keratin, the main protein in bird feathers, in immunological tests.
- Shortly after the 1859 publication of Charles Darwin's The Origin of Species, British biologist and evolution-defender Thomas Henry Huxley proposed that birds were descendants of dinosaurs. He cited skeletal similarities, particularly among some saurischian dinosaurs, fossils of the 'first bird' Archaeopteryx and modern birds. In 1868 he published On the Animals which are Most Nearly Intermediate between Birds and Reptiles, making the case. The leading dinosaur expert of the time, Richard Owen, disagreed, claiming Archaeopteryx as the first bird outside dinosaur lineage. For the next century, claims that birds were dinosaur descendants faded, with more popular bird-ancestry hypotheses including 'crocodylomorph' and 'thecodont"'ancestors, rather than dinosaurs or other archosaurs. Then, in 1964, John Ostrom discovered a fossilized dinosaur he called Deinonychus antirrhopus, a theropod whose skeletal resemblance to birds seemed unmistakable. Ostrom has since become a leading proponent of the theory that birds are direct descendants of dinosaurs. Further comparisons of bird and dinosaur skeletons, as well as cladistic analysis strengthened the case for the link, particularly for a branch of theropods called maniraptors. Skeletal similarities include the neck, the pubis, the wrists (semi-lunate carpal), the 'arms' and pectoral girdle, the shoulder blade, the clavicle and the breast bone. In all, over a hundred distinct anatomical features are shared by birds and theropod dinosaurs. By the 1990s, most paleontologists considered birds to be surviving dinosaurs and referred to 'non-avian dinosaurs' (those that went extinct), to distinguish them from birds (aves or avian dinosaurs). Some dinosaur restorations began to picture dinosaurs with a downy or feathery cover. Direct evidence to support the theory was missing, however. Some mainstream ornithologists including Smithsonian Institute curator Storrs L. Olson, disputed the links, citing the lack of fossil evidence for feathered dinosaurs.
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