Dinosaurs had 'earliest feathers'
By Jonathan Amos for BBC News
24 September 2009
Exceptionally well preserved dinosaur fossils uncovered in north-eastern
China display the earliest known feathers. The creatures are all more than 150
million years old. The new finds are indisputably older than Archaeopteryx, the
oldest recognised bird discovered in Germany. Professor Xu Xing and colleagues
tell the journal Nature that this represents the final proof that dinosaurs
were ancestral to birds. The theory that birds evolved from dinosaurs has
always been troubled by the absence of feathers more ancient than those on the famous
Archaeopteryx. This has given critics room to question the idea. But the new
fossils, which come from two separate locations, are in most cases about 10
million years older than the German bird discovered in the late 19th Century. One
of the dinosaurs, named Anchiornis huxleyi, is spectacular in its preservation.
It has extensive plumage covering its arms and tail, and also its feet - a
"four-winged" arrangement, says Professor Xu from the Chinese Academy
of Science in Beijing.
"The first specimen we discovered earlier this year was
incomplete," he told BBC News. "Based on that specimen, we named it
Anchiornis; and we thought it was a close relative of birds. But then we got a
second specimen, which was very complete - beautifully preserved.
"Based on this second specimen, we realised that this
was a much more important species, and definitely one of the most important species
for our understanding of the origin of birds and of their flight." Professor
Xu believes the four-winged shape may have been a very important stage in the
evolutionary transition from dinosaurs to birds. Details of the latest
discoveries have been presented this week at the annual meeting of the Society
of Vertebrate Paleontologists, being held this year at the University of
Bristol, UK. The renowned Bristol palaeontologist Michael Benton said the announcement
was immensely exciting. "Drawing the tree of life, it's fairly obvious
that feathers arose before Archaeopteryx appears in the fossil record," he
told BBC News. "Now these fantastic new discoveries by Professor Xu Xing
prove that once and for all. "These new discoveries are maybe 10 million
years older than Archaeopteryx."
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