Scientists have found the most elaborately dressed dinosaur ever described, and say it sheds new light on how birds like peacocks have inherited their ability to show off.
The new species, Ubirajara jubatus, was the size of a chicken, with a mane of long fur on its back and stiff bands protruding from its shoulders, features never seen before in the fossil record.
Its flamboyant properties are believed to have been used to blind partners or intimidate enemies.
An international team of scientists led by Professor David Martill and the researcher Robert Smyth from the University of Portsmouth and Professor Dino Frey from the State Museum of Natural History in Karlsruhe discovered the new species while studying fossils in the Karlsruhe collection.
The study was published in the journal Cretaceous Research.
Professor Martill said, “What is particularly unusual about the animal is the presence of two very long, probably stiff, ligaments on either side of its shoulders, which are probably used for display, attraction, rivalry between men, or deterring enemies were.
“We cannot prove that the specimen is a male, but given the differences between male and female birds, it seems likely that the specimen was both male and young, which is surprising since most of the complex rendering skills are reserved for mature adult males .
“In view of its extravagance, we can imagine that the dinosaur indulged in an elaborate dance to demonstrate its exhibition structures.”
The ribbons are neither scales nor fur nor feathers in the modern sense. They appear to be structures that are unique to this animal.
Mr Smyth said, “These are such extravagant features for such a small animal and not at all what we would predict if only we had the skeleton. Why should you dress up in a way that makes you more obvious to both your prey and potential predators?
“The truth is that for many animals, evolutionary success is more than just survival. You also have to look your best if you want to pass your genes on to the next generation.
“Modern birds are famous for their elaborate plumage and displays used to attract mates. The peacock’s tail and the male birds of paradise are examples of this. Ubirajara shows us that this tendency to show off is not a unique bird trait, but something that birds inherited from their dinosaur ancestors. “
Ubirajara jubatus lived about 110 million years ago in the Aptian phase of the Cretaceous and is closely related to the European Jurassic dinosaur Compsognathus.
Part of the long, thick mane that runs down the animal’s back is almost intact. The arms were covered with fur-like filaments up to the hands.
It is believed that the mane was controlled by muscles that make it possible to lift it. Similarly, a dog will raise its hoes or a porcupine will raise its quills when threatened.
Ubirajara could lower its mane close to the skin when not in display mode, allowing the creature to move quickly without getting tangled in the vegetation.
Professor Martill said: “Any creature with movable hair or feathers as body cover has a great advantage in optimizing the body contour for faster hunts or escapes, but also trapping or emitting heat.”
The mane isn’t the only remarkable feature.
The researchers describe the creature’s long, flat, stiff shoulder ligaments made of keratin as “puzzling,” with a small sharp crest running down the middle. These bands were positioned so that the freedom of movement in the arms and legs is not impaired, so that the animal’s ability to chase, groom and send signals would not have been restricted.
Mr Smyth argues that Ubirajara’s elaborate plumage may have improved its chances of survival.
He said, “We know that many dinosaurs had bony crests, spines and ruffles that were likely to be displayed, but we don’t see these very often in live birds. In birds, the combs are made of feathers.
“This little dinosaur gives an insight into why this might be the case.
“Bones require a lot of energy for a body to grow and maintain. It is also heavy and can cause serious injury if broken.
“Keratin – the material that makes hair, feathers, and scales – is a much better display alternative for a small animal like this one. The production of keratin is cheaper for a body, it is also light, flexible and can be replaced regularly if damaged.
“Ubirajara is the most primitive known dinosaur that has integer representation structures. It is a revolution in dinosaur communication, the effects of which we can still see in living birds today. “
Professor Frey dug the sample out of the two stone slabs it lay in and used X-rays to find previously hidden skeletal elements and soft tissue so the researchers could get a clear picture of its features.
Ubirajara jubatus is the first non-avian dinosaur to be described from the Brazilian Crato Formation, a shallow inland sea that was created about 110 million years ago. It is also the first non-avian dinosaur found on the ancient supercontinent of Gondwana with preserved skin.
Another researcher on the team, Hector Rivera Sylva of the Museo del Desierto, Mexico, said the discovery that constitutes a watershed in the area is important to America as well.
He said, “The Ubirajara Jubatus is important not only because of the integumentary structures that are first present in a non-avian dinosaur that completely change the way certain dinosaurs look at things. Rather, the scientific value goes beyond the limit and forms a watershed, as it is the first evidence of this group in Latin America, as well as one of the few reported for the subcontinent of Gondwana, expanding knowledge of non-avian feathered dinosaurs for America . their evidence is very rare. “