A dinosaur with 'hair' and 'ribbons' leaves researchers intrigued

Researchers have discovered that a two-legged chicken-sized Cretaceous Period dinosaur made a living hunting insects and perhaps small vertebrates like frogs and lizards about 110 million years ago along the shores of an ancient lagoon in what is now northeastern Brazil.

On the inside, it was ordinary, with a skeleton similar to many small dinosaurs from the preceding Jurassic Period, scientists said on Tuesday.

It was, however, different on the outside.

This dinosaur, called Ubirajara jubatus, possessed a mane of hair-like structures while also boasting two utterly unique, stiff, ribbon-like features probably made of keratin - the same substance that makes up hair and fingernails - protruding from its shoulders.

Ubirajara's hair-like structures appear to be a rudimentary form of feathers called protofeathers. This was not actual hair, an exclusively mammalian feature. Many dinosaurs had feathers. In fact, birds evolved from small feathered dinosaurs about 150 million years ago.

Scientists said it, most likely, had hair-like protofeathers over much of its body but they are only preserved along its neck, back and arms. The ones on its back are very long and give it a sort of mane that is unique for dinosaurs.

Ubirajara's ribbon-like structures may have been used for display, possibly to attract mates or intimidate adversaries or in inter-male rivalry. Such displays often are made by male animals - think of a peacock's elaborate tail feathers - leading Martill to make an "educated guess" that this Ubirajara individual was male.

While it is impossible to know from the fossil, researchers said Ubirajara may have been colorful.