Washington, Apr 29 (ANI): Analysis of newfound fossils of a feathered dinosaur has suggested that the extinct reptiles might have had a diversity in plumage types that puts modern birds to shame.
Farmers in northeastern China have unearthed two roughly 125-million-year-old specimens of the dinosaur Similicaudipteryx- a member of the group called the oviraptorosaurs, which are believed to be ancestors of birds.
The species, believed to be herbivorous, was first described in 2008-it had robust jaws similar to those of other oviraptorosaurs, but with two unusually large buck teeth.
The two new fossils belong to a pigeon-size juvenile dinosaur thought to be just a year or two old and a three- to four-year-old duck-size youth.
The younger animal's fossil included short ribbonlike feathers and each feather on its tail was just 1.6 inches (4 centimeters) long, while on its arms a typical feather was less than 0.8 inch (2 centimeters) long.
On the other hand, the older dinosaur sported long quills, with each tail feather measuring 13.7 inches (35 centimeters) long and a typical arm feather measuring roughly 9.8 inches (25 centimeters) long.
The findings suggest feathered dinosaurs might have been undergone a string of changes as they matured-unlike anything seen in modern birds, said study co-author Xing Xu of the Chinese Academy of Sciences in Beijing.
It is believed that very young dinosaurs have been covered in down, so the new finding suggests that dinosuars went through at least three stages of feather types- full down, to a mix of down and "ribbons," to down and quills.
The long quills on the older Similicaudipteryx are much like those seen on modern birds, and they might have served as ornaments or to help the dinosaur balance itself as it ran.
The younger dinosaur's ribbonlike feathers are superficially similar to some specialized plumes seen today, for example, on birds of paradise.
However, the ancient feathers are actually a type that has been lost in the course of evolution, and the role they played on the younger juvenile remains unknown.
These extinct feathers would not have been useful for warmth, for example, given how flat they are, said Xu.
While the "ribbons" might have served as ornaments, "in modern animals, structures used for display generally develop relatively late, when the animal is mature, for attracting mates," he added.
"Their appearance here is at the wrong stage-it's really bizarre," National Geographic News quoted him as saying.
Similicaudipteryx's odd changes suggest that early birds and feathered dinosaurs experimented with a diversity of feather types and a variety of ways to use them, "which only later stabilized to the more conservative system we see now with modern birds," said Xu.
"There were very, very strange structures in the history of feathers," he added.
The feathered dinosaurs are described in the latest issue of the journal Nature. (ANI)
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