|
'Birds did not evolve from dinosaurs' Washington: For long it was believed that modern birds had evolved from a species of flying dinosaurs, known as pterodactyl, but now that theory has been challenged by a well renowned ornithologist. Dr Alan Feduccia, a renowned ornithologist from the University of North Carolina, has said that although modern birds and the dinosaurs had some ancestors common to them, it would however, be wrong to say that modern birds evolved from dinosaurs. "We all agree that birds and dinosaurs had some reptilian ancestors in common. But to say dinosaurs were the ancestors of the modern birds we see flying around outside today, because we would like them to be, is a big mistake," he said. He refuted suggestions that the earliest birds or flying dinosaurs had any feathers, and said that the earliest known rudimentary feathers as revealed by fossils, were not feathers at all, but bits of decomposed skin and supporting tissues that just barely resembled feathers. "The theory that birds are the equivalent of living dinosaurs and that dinosaurs were feathered is so full of holes that the creationists have jumped all over it, using the evolutionary nonsense of 'dinosaurian science' as evidence against the theory of evolution. To paraphrase one such individual, 'This isn't science . . . This is comic relief'," Feduccia added. For his studies, which appear in Journal of Morphology published online, Dr Feduccia and his team used powerful microscopes to examine the skin of modern reptiles, the effects of decomposition on skin and the fossil evidence relating to alleged feather progenitors, also known as "protofeathers." Findings revealed the existence of fossilized patterns resembling feathers that are also found in fossils, not closely related to birds. This, Feduccia said, was more likely to be skin related tissues than feathers. "Collagen is a scleroprotein, the chief structural protein of the connective tissue layer of skin. Naturally, because of its low solubility in water and its organization as tough, inelastic fiber networks, we would expect it to be preserved occasionally from flayed skin during the fossilization process," he said. Feduccia said that the strongest case for feathered dinosaurs arose in 1996 with a small black and white photo of the early Cretaceous period small dinosaur Sinosauropteryx, which sported a coat of filamentous structures some called "dino-fuzz", adding that it was never ever proved that dinosaurs had feathers. "The
photo subsequently appeared in various prominent publications as the
long-sought 'definitive' evidence of dinosaur 'feathers' and that birds
were descended from dinosaurs. Yet no one ever bothered to provide evidence
-- either structural or biological -- that these structures had anything
to do with feathers. In our new work, we show that these and other filamentous
structures were not protofeathers, but rather the remains of collagenous
fiber meshworks that reinforced the skin," he said. "Just as the discovery
of a four-chambered heart in a dinosaur described in 2000 in an article
in Science turned out to be an artefact, feathered dinosaurs too have
become part of the fantasia of this field. Much of this is part of the
delusional fantasy of the world of dinosaurs, the wishful hope that
one can finally study dinosaurs at the backyard bird feeder. It is now
clear that the origin of birds is a much more complicated question than
has been previously thought," he further said. References: India Travel Times, News, Hotels, Airlines, Indian, Tourism, Tourist, Tour, Ayurveda, Yoga, Hotel |
Travel
Sites
Tourist
offices |