Feathered dinosaur throws bird evolution into a flap

The creature, found in China, belonged to a large group of dinosaurs previously thought to have no connection with birds or feathers.

Yet its fossil remains contain clear signs of feather-like structures, including long tail filaments.

It is well known that birds are small dinosaurs with feathers. They are believed to be descended from theropods, carnivorous dinosaurs which stood on two legs such as Tyrannosaurus rex and Velociraptor.

A number of theropod fossils have been discovered bearing the remains of primitive feathers, thought to have been used for insulation or display rather than flight.

But the newly discovered dinosaur, named Tianyulong confuciusi, was not a theropod. It did not even belong to the vast group called Saurischia which included theropods, early birds and huge plant-eating dinosaurs such as Brachyosaurus.

Tianyulong was part of the other large dinosaur group, Orinithischia, which included duck-billed hadrosaurs and the armoured Triceratops and Stegosaurus.

The dinosaur dates back to the early Cretaceous period, around 130 million years ago. Its incomplete fossil skeleton was found in Liaoning Province, north-eastern China, the home of many other feathered dinosaurs.

Even in its own time, Tianyulong was a "living fossil", bearing features tying it to a group of herbivorous dinosaurs that evolved 70 million years earlier.

Discussing the research in Nature, US expert Dr Lawrence Witmer, from Ohio University, wrote: "Perhaps the only conclusion that can be drawn... is that little Tianyulong has made an already confusing picture of feather origins even fuzzier."