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 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.
This dinosaur, called Ubirajara jubatus, had a mane of hair-like structures, while also showing off two utterly unique, stiff, ribbon-like features likely made of keratin – the same substance that makes up hair and fingernails – protruding from his shoulders.
“There are plenty of other strange dinosaurs, but this one is unlike any other,” said David Martill, a paleobiology professor at 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.
“Probably from a distance it looked hairy rather than fluffy,” said Martill. “It probably had hair-like protophiles all over much of his body, but they have only been preserved along his neck, back and arms. The ones on its back are very long and give it a kind of 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 about the fossil – which arrived at a museum in Ceará state in the early 1990s, ScienceNews reported – Martill said Ubirajara may have been colorful.
“I bet it was,” he added.
Guardian personnel contributed to this report