By Will Dunham
WASHINGTON (Reuters) – About 110 million years ago, along the shores of an ancient lagoon in what is now northeastern Brazil, a two-legged dinosaur the size of a Cretaceous period chicken lived by hunting insects and perhaps small vertebrates animals such as frogs and lizards.
On the inside, it was ordinary, with a skeleton that resembles many small dinosaurs from the prior Jurassic period, scientists said Tuesday. On the outside, it was anything but.
Called Ubirajara jubatus, this dinosaur had a mane of hair-like structures, while also showing off two completely unique, stiff, ribbon-like features likely made of keratin – the same substance that made up hair and fingernails – that protruded from its shoulders.
“There are plenty of other strange dinosaurs, but this one is unlike any other,” said paleobiology professor David Martill of the University of Portsmouth in England, who helped lead the study published in the journal Cretaceous Research.
Ubirajara’s hair-like structures appear to be a rudimentary form of feathers called protofeathers. This was not real hair, an exclusive mammalian feature. Many dinosaurs had feathers. In fact, birds evolved from tiny feathered dinosaurs about 150 million years ago.
“From a distance it probably looked hairy rather than fluffy,” said Martill. “He probably had hair-like protofeathers all over much of his body, but they are only preserved along his neck, back and arms. The specimens on his back are very long and give him a mane unique to dinosaurs. “
Ubirajara’s ribbon-like structures may have been used for display, possibly to attract partners or intimidate opponents or in male rivalry, Martill added. Such displays are often made by male animals – think of a peacock’s elaborate tail feathers – making Martill an “educated guess” that this Ubirajara person was a man.
“The ribbons that seem to come off the shoulders are like nothing I’ve seen in nature before,” said Martill.
While it’s impossible to know from the fossil, Martill said Ubirajara may have been colorful.
“I bet it was,” he added.
(Reporting by Will Dunham; edited by Jonathan Oatis)