Feathered dinosaurs were even fluffier than believed: Study

London: Scientists have found that the feathered species of dinosaurs that are believed to have roamed the surface of the earth approximately over 125 million years ago, were fluffier than previously thought.

Modern birds are the direct descendants of a group of feathered, carnivorous dinosaurs that, along with true birds, are referred to as paravians -- which also include Anchiornis, a crow-sized dinosaur species.

In the study, the research team from University of Bristol examined, an exceptionally-preserved fossil of Anchiornis and compared its fossilised feathers to those of other dinosaurs and extinct birds.

They found that the feathers around the body of Anchiornis, known as contour feathers, revealed a newly-described, extinct, primitive feather form consisting of a short quill with long, independent, flexible barbs erupting from the quill at low angles to form two vanes and a forked feather shape.

Such feathers would have given Anchiornis a fluffy appearance relative to the streamlined bodies of modern flying birds, whose feathers have tightly-zipped vanes forming continuous surfaces. 

Anchiornis's unzipped feathers might have also affected the animal's ability to control its temperature and repel water, the researchers said.

In addition, compared to modern flight feathers, the feathers on the wing of Anchiornis lack the aerodynamic, asymmetrical vanes, but these paravians were packed with multiple rows of long feathers into the wing.

"Overall, our study provides some new insight into the appearance of dinosaurs, their behaviour and physiology, and the evolution of feathers, birds, and powered flight," said Evan Saitta from the varsity.

For the new study, appearing in the journal Paleontology, the team also created what is potentially the most accurate depiction of any dinosaur species to date and which represents a radical shift in dinosaur depictions.

"The novel aspects of the wing and contour feathers, as well as fully-feathered hands and feet, are added to the depiction. This contrasts much previous art that places paravians perched on top of branches like modern birds," Saitta noted.