A University of Alberta researcher's examination of fossilized dinosaur tail bones has led to a breakthrough finding: some feathered dinosaurs used tail plumage to attract mates, much like modern-day peacocks and turkeys.
U of A Paleontology researcher Scott Persons followed a chain of fossil evidence that started with a peculiar fusing together of vertebrae at the tip of the tail of four different species of dinosaurs, some separated in time and evolution by 45 million years.
Persons says the final vertebrae in the tails of a group of dinosaurs called oviraptors were fused together forming a ridged, blade-like structure. "The structure is called a pygostyle" says Persons. "Among modern animals only birds have them."
Researchers say fossils of Similicaudiptery, an early oviraptor, reveals feathers radiating from the fused bones at the tail tip. Similicaudipterywas not known to be a flying dinosaur and Persons contends its tail feathers evolved as a means of waving its feathered tail fans.
No direct fossil evidence of feathers has been found with the fossils of the oviraptors that followed Similicaudiptery, but Persons says there is still strong evidence they had a feathered tail.
Persons reasons that because the later oviraptor had the same tail structure as the feathered Similicaudipteryx, the tails of later oviraptors' still served the same purpose, waving feathered tail fans.
Persons says the hypothesis of oviraptor tail waving is supported by both the bone and muscle structure of the tail.
Individual vertebrae at the base of an oviraptor's tail were short and numerous, indicating great flexibility. Based on dissections of modern reptile and bird tails, Persons reconstruction of the dinosaur's tail muscles revealed oviraptors had what it took to really shake their tail feathers.
Large muscles extended far down the tail and had a sufficient number of broad connection points to the vertebrae to propel oviraptor's tail feathers vigorously from side to side and up and down.
Oviraptors were two-legged dinosaurs that had already gone through major diversifications from the iconic, meat eating dinosaur family. Oviraptors were plant eaters that roamed parts of China, Mongolia, and Alberta during the Cretaceous period, the final age of the dinosaur.
"By this time a variety of dinosaurs used feathers for flight and insulation from the cold, "said Persons. "This shows that by the Late Cretaceous dinosaurs were doing everything with feathers that modern birds do now," said Persons.
In addition to feathered-tail waving, oviraptors also had prominent bone crests on their head, which Persons says the dinosaur also may have used in mating displays.
"Between the crested head and feathered-tail shaking, oviraptors had a propensity for visual exhibitionism," said Persons.
Persons, a U of A PhD candidate in paleontology was the lead researcher on the paper which was published Jan. 4 in the international journal Acta Palaeontologica Polonica
University of Alberta: http://www.ualberta.ca
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Free-living songbirds show increased stress hormone levels when nesting under white street lights. But different light spectra may have different physiological effects as this study finds, suggesting that using street lights with specific colour spectra may mitigate effects of light pollution on wildlife
Scientists identify the condition aphantasia, in which people cannot create images in their head
The dust in our homes contains an average of 9,000 different types of fungi and bacteria, a study suggests.
A mosquito can bear up to 23 times its total body weight on each leg, which is crucial for landing on water – the insect's secret is way it stands
Tropical species with smaller geographical ranges are more likely to die out in a warming climate than those that can adapt by ‘invading’ new regions
Most people think of bacteria as germs, signs of filth, or unwanted bringers of disease. Slowly, that view …
The gloomy octopuses crowded at Jervis Bay, Australia, appear to spit and throw debris such as shell at each other in what could be an intentional use of weapons
Therapies based on hormones that make us more trusting enhance our natural placebo effect – a finding that could alter the way clinical trials are conducted
The blind, hairless babies born recently at Washington D.C.'s National Zoo are completely dependent on their mothers—who can sometimes accidentally crush them.
The poop-hoarding insects have an amazingly advanced internal GPS that allows them to navigate by day or night.