While dinosaurs can sometimes be thought of as ferocious or imposing, a team of researchers revealed how they would dance as part of a mating ritual.
Published in the journal Scientific Reports, the new study detailed a behavior known as "scraping," which birds today are known to do when they mate. The researchers found evidence theropod dinosaurs performed this scraping to attract mates.
"We started cleaning them off and taking a closer look at them, and we knew right away that there was something unusual about them," study co-author Martin Lockley, an emeritus professor of geology at the University of Colorado, told Live Science. "We were calling them 'digging dinosaur' traces.
"They were obviously made by the feet of dinosaurs, because we could see the claw marks. We could see two sides, a left and a right trough, with a ridge in the middle."
The scraping marks the researchers examined were made some 100 million years ago in Dakota sandstone in modern-day western Colorado. In order to take a closer look at them, the researchers had to create a 3-D rendering since cutting the prints out of the rock was out of the question.
"While these findings are, in one sense, certainly surprising, in another sense they are predictable, as many birds - from hermit hummingbirds to the ostrich - perform courtship displays in leks," Mark Riegner, an ornithologist and a professor of environmental studies at Prescott College, told Discovery News. "So perhaps it was only a matter of time, and a keen eye for recognition, until such Cretaceous arenas were discovered."