Chicken-sized prehistoric creature helps experts understand avian development

Scientists may have made a breakthrough in understanding the origins of how birds show off their plumage after finding a previously unknown chicken-sized species with long fur and stiff ribbon-type projections in a collection of samples at the State Museum of Natural History, in Karlsruhe, Germany.

An international team, led by the museum's Dino Frey and David Martill and Robert Smyth from the University of Portsmouth in England, made the discovery of what has been described as one of the most elaborate-looking prehistoric creatures ever known.

The fossil came from the Crato Formation in Brazil, a shallow inland sea dating back around 110 million years, and has been named ubirajara jubatus, with ubirajara meaning lord of the spear in the language of the indigenous Tupi people, a reference to its elongated spikes, and jubatus from the Latin word meaning crested.

"What is especially unusual about the beast is the presence of two very long, probably stiff ribbons on either side of its shoulders that were probably used for display, for mate attraction, inter-male rivalry or to frighten off foe," said Martill.

"Given its flamboyance, we can imagine that the dinosaur may have indulged in elaborate dancing to show off its display structures."

The team's findings have been published in scientific journal Cretaceous Research, and Smyth said the ribbon-style projections were particularly fascinating as they were not scales, fur or what would be regarded as feathers, and so raise many questions, while potentially showing a connection to modern creatures, such as peacocks.

"These are such extravagant features for such a small animal and not at all what we would predict if we only had the skeleton preserved," he said.

"Why adorn yourself in a way that makes you more obvious to both your prey and to potential predators? The truth is that for many animals, evolutionary success is about more than just surviving, you also have to look good if you want to pass your genes on to the next generation.

"Modern birds are famed for their elaborate plumage and displays that are used to attract mates. The peacock … is a textbook example of this. Ubirajara shows us that this tendency to show off is not a uniquely avian characteristic, but something that birds inherited from their dinosaur ancestors."

Large parts of the sample were almost entirely intact, which is hugely helpful for analysis. A thick mane ran down the creature's back, and that is believed to have been controlled by muscles allowing it to be raised, in a similar way to how a porcupine reacts when alarmed. The ability to lower the mane would allow for ease of passage through undergrowth.

"Any creature with movable hair or feathers… has a great advantage in streamlining the body contour for faster hunts or escapes but also to capture or release heat," said Martill.