New
York, NY (4/25/01)- The discovery of a feather-covered dinosaur
in Northern China raises questions not only about the origins of birds, but
about the nature of dinosaurs themselves. The remarkably intact specimen strengthens
the case for the theory that birds evolved from theropod dinosaurs, while
suggesting that many other dinosaurs may have had feathers to keep them warm.
The fossil skeleton, estimated to be somewhere between 126-147 million years
old, was discovered by a team of American and Chinese scientists in the Yixian
Formation in the Liaoning Province, China. Feather-like tufts and barbs can
be seen on other parts of the specimen. It is the first ever dinosaur to be
unearthed with its body covering intact. The researchers were stunned to find
that the body was covered in fine, feather-like filaments. The specimen has
been identified as a type of dromaeosaur, cousin to the velociraptor brought
so frighteningly to life in "Jurassic Park". The find may ruffle
some feathers in the paleontology community, where a debate continues to rage,
on the link, or lack of link between dinosaurs and birds.The new discovery
suggests that feathers preceded not only birds, but flight as well.
"This fossil radically modifies our vision of these extinct animal.
It shows us that advanced theropod dinosaurs may have looked more like weird
birds than giant lizards,"" said Mark Norell, Chairman of the Division
of Paleontology at the American Museum of Natural History.
Dromaeosaurs are part of the theropod group of dinosaurs. There has been
a consensus among many, but not all, paleontologists, that the striking number
of anomatic similarities between theropods and modern birds suggests that
this is the most likely link between dinosaurs and the bird world. Since the
middle of the 19th century, scientists have noticed that modern birds and
therapods share a number of major skeletal characteristics including: the
shape and position of the pubic bone; elongated arms with claws; hollow, thin
bones; and stiffened tails. The fact that reptiles have scales, which are
produced by tissues similar to feathers, and that birds have scales on their
feet has also not been overlooked. Finally, it is hard to miss the most obvious
similarity of all, the fact that both lay eggs.
This is not the first example of feather-like structures to be discovered
at the Yixian Formation fossil beds. During the past five years many fragments
have been unearthed. However, the incomplete nature of those finds made it
difficult to assert with certainty which bone belonged with which skeleton.
The new find is virtually complete. Since dromaeosaurs are known to be more
primitive than birds, the new fossils lends support to the idea that feathers
developed before flight. Researchers speculate that the feathery coat may
have helped the dinosaurs to keep warm, or may have been used to attract mates.
"This is the specimen we've been waiting for. It makes it indisputable
that a body covering similar to feathers was present in non-avian dinosaurs,"
asserted Ji Qiang, of the Chinese Academy of Geological Sciences, leader of
the expedition.
The research appears in the April 26, 2001 issue of the journal Nature. The
fossil is on loan from the National Geological Museum of China to the American
Museum of Natural History. It can be seen at that New York City location from
April 25.
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