The first ever example of a plant-eating dinosaur with feathers and scales has been discovered in Russia. Previously only flesh-eating dinosaurs were known to have had feathers so this new find indicates that all dinosaurs could have been feathered. The new dinosaur, named Kulindradromeus zabaikalicus, as it comes from a site called Kulinda on the banks of the Olov River in Siberia, is described in a paper published today in Science. Our colleague and lead author of the article, palaeontologist Pascal Godefroit presents this discovery in short videos that can be viewed at the bottom of this page.
Birds evolved from dinosaurs over 150 million years ago so it was no surprise when dinosaurs with feathers were found in China in 1996. But all those feathered dinosaurs were theropods, flesh-eating dinosaurs that include the direct ancestors of birds.
Kulindadromeus shows reptile-like scales on its tail and shins, and short bristles on its head and back. The most astonishing discovery, however, is that it also has complex, compound feathers associated with its arms and legs.
Lead author Dr Pascal Godefroit from the Royal Belgian Institute of Natural Sciences (RBINS) in Brussels said: "I was really amazed when I saw this. We knew that some of the plant-eating ornithischian dinosaurs had simple bristles, and we couldn’t be sure whether these were the same kinds of structures as bird and theropod feathers. Our new find clinches it: all dinosaurs had feathers, or at least the potential to sprout feathers."
The Kulinda site was found in summer 2010 by Sofia Sinitsa and her team from the Institute of Natural Resources, Ecology and Cryology SB RAS in Chita, Russia. Over several summer digs, the Russian-Belgian team excavated many dinosaur fossils, as well as those of plants and insects.
Well-preserved feathers
The feathers were studied by Dr Maria McNamara of University College Cork, Ireland, and Professor Michael Benton of the University of Bristol, who has also worked on the feathers of Chinese dinosaurs.
Dr McNamara said: "These feathers are really very well preserved. We can see each filament and how they are joined together at the base, making a compound structure of six or seven filaments, each up to 15mm long."
Feather expert, Danielle Dhouailly from the Université Joseph Fourier in La Tronche, France said: "The feathers look like down feathers from some modern chickens. When we compare them with the leg scales, it looks as if the scales are aborted feathers, an idea that has been suggested to explain why modern birds also have scaly bare legs."
Small and primitive
Kulindadromeus was a small plant-eater, only about 1m long. It had long hind legs and short arms, with five strong fingers. Its snout was short, and its teeth show clear plant eating adaptations. In evolutionary terms, it sits low in the evolutionary tree of ornithischian dinosaurs. There are six skulls and several hundred bones of this new dinosaur at the Kulinda locality.
This discovery suggests that feather-like structures were likely widespread in dinosaurs, possibly even in the earliest members of the group. Feathers probably arose during the Triassic, more than 220 million years ago, for purposes of insulation and signalling, and were only later co-opted for flight. Smaller dinosaurs were probably covered in feathers, mostly with colourful patterns, and feathers may have been lost as dinosaurs grew up and became larger.
