Washington, September 30 : Scientists have said that the oldest known dinosaur relative of birds had "bizarre" anatomy, including long, ribbon-like tail feathers that suggest plumage may have first evolved for show rather than for flight.
According to a report in National Geographic News, farmers unearthed a fossil of the new dino species, dubbed Epidexipteryx hui, from the hills of Inner Mongolia in late 2007.
The remains date back 152 million to 168 million years ago, making the newfound creature slightly older than Archaeopteryx, the most primitive known bird.
Like other avialans - birds and their closest dinosaur relatives - Epidexipteryx is a theropod, a group of two-legged animals that includes Tyrannosaurus rex.
Researchers think the pigeon-size Epidexipteryx might have used its plumes as flashy ornaments, since it was mostly covered in short feathers that lack the structure necessary for flight.
"For example, the feathers could potentially have played a role in displays intended to attract a mate, scare off a rival, or send a warning signal to other individuals of the same species," said study co-author Fucheng Zhang, a paleontologist at the Chinese Academy of Sciences in Beijing.
"This is very exciting indeed, since it gives us a window into a stage of avialan history just preceding the appearance of the classic first bird," he added.
"It shows that the use of feathers for visual communication-as opposed to other functions such as insulation and flight-was a very early development," he further added.
According to Luis Chiappe, a paleontologist with the Natural History Museum of Los Angeles County, the mosaic of features suggests that there was a lot of evolutionary experimentation around the origin of birds, with many different kinds of lineages reaching different levels of birdness.
Epidexipteryx lived in the mid- to late Jurassic period in a lush, well-vegetated area that was rich in salamanders and other possible prey.
The dinosaur had claws similar to those of ground-foraging birds, such as ostriches and turkeys, and its front teeth were large and protruding.