Newly Discovered Fossils Suggest That All Dinosaurs May Have Had Feathers
redOrbit Staff & Wire Reports – Your Universe Online
An international team of researchers has discovered the first-ever fossils belonging to a plant-eating dinosaur that contained both scales and featherlike structures, suggesting that plumage might have been present in a far greater number of species than previously believed.
The fossils were discovered in Siberia and belong to a species identified as Kulindadromeus zabaikalicus, according to Dan Vergano of National Geographic. The creature was a 4.5-foot-long, two-legged running “ornithischian” beaked dinosaur, and the newly-discovered remains date back to approximately 160 million years ago.
“Over the past two decades, discoveries in China have produced at least five species of feathered dinosaurs,” Vergano said. However, all of those creatures belonged to a group of raptor-type dinosaurs known as theropods. This species is the first to be “ancestrally distinct” from those creatures, which were ancestors of modern birds.
“Probably that means the common ancestor of all dinosaurs had feathers,” Dr. Pascal Godefroit of the Royal Belgian Institute of Natural Science, lead author of a new research paper that details the find and appears in the July 25 edition of the journal Science, told National Geographic.
Dr. Godefroit and his colleagues recovered six skulls and several other bones at Kulinda Valley in Siberia, said Rachel Feltman of The Washington Post. The researchers said the feathers of Kulindadromeus would have varied from primitive bristle-like ones used to insulate the warm-blooded lizards to downy feathers similar to those found in modern birds.
In addition to feathers, the Royal Belgian Institute of Natural Sciences noted that the new creature also had reptile-like scales on its tail and shins, long hind legs and short arms – the latter of which meant that it was highly unlikely any of the feathers were used for flight. It also had a short snout and teeth that were clearly designed for eating plants.
“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,” Dr. Godefroit said. “Our new find clinches it: all dinosaurs had feathers, or at least the potential to sprout feathers.”
The Kulinda site was originally discovered by Sofia Sinitsa and her team from the Institute of Natural Resources, Ecology and Cryology SB RAS in Chita, Russia back in the summer of 2010. The Kulindadromeus fossils were excavated over the course of several summers, and were analyzed by Dr. Maria McNamara of University College Cork in Ireland and Professor Michael Benton of the University of Bristol in the UK.
Dr. McNamara said that the feathers were “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.” Colleague Danielle Dhouailly, a feather expert from the Université Joseph Fourier in La Tronche, France, compared the feathers to the down of some modern chickens, and said that the scales resembled “aborted feathers.”
As for the feathers, Dr. Dave Hone of The Guardian said that there were multiple types which had been preserved across several different Kulindadromeus specimens, including simple filaments on the head, neck and body similar to theropod feathers and shorter versions of those found in ornithischians
The researchers also found tiny ribbon-like strips composed of multiple filaments which comprise what Dr. Hone said appears to be a new type of cover, and multiple filaments on the upper arms and upper legs that appear to originate from one central point. This marks the first time that multiple filaments of this kind have been observed in ornithischians, meaning that it represents a lineage that is “very well separated from the theropods.”
“It cannot be said right now that any of the various filaments seen in Kulindadromeus are genuinely feathers in the sense that they share a single evolutionary origin back at the very origin of the dinosaurs and before the ornithischians split from the theropods and sauropodomorphs,” he added. “However… it does open up the potential that many more dinosaurs had filaments of some description.”