Dinosaurs danced to impress potential mates, stamping their feet and scratching the earth much like modern day birds, new research from local paleontologists suggests.
Richard McCrea and Lisa Buckley, scientists at the Peace Region Paleontology Research Centre, helped make the discovery at a number of sites in Colorado over the last year, where there are deep, fossilized footprints and scratch marks believed to be from dinosaur mating displays.
The courtship display traces were made by large meat-eating dinosaurs and found in 100-million-year-old rocks. The impressions left on the earth’s surface are large, with the biggest ones around two-metres in diameter, and as deep as 40 centimetres.
“We have a lot of these traces packed into one area, so it was very likely that they were made by multiple animals because they are slightly differently shaped, slightly different sizes,” Buckley explained in an interview.
“And rather than just one animal going nuts and digging up an entire area, it makes more sense to have multiple animals doing these traces, so very likely they were facing off with each other and trying to put on the best show possible.”
The findings were published Jan. 7 in the Scientific Reports journal. Buckley and McCrea were two of the paper’s 15 co-authors.
While the evidence of these so-called “display arenas” so far only documents the mating displays of large carnivorous dinosaurs, it’s possible the behavior was commonplace.
“I think the only reason that this kind of behavior was preserved is because it was done by a rather large animal,” Buckley said.
“I mean, these types of little traces are done by small shore birds all the time, but they’re so small so they erode away quickly. I imagine that would be the same with the small dinosaurs too, the small dinosaurs – the pun is completely intended – just scratch the surface, whereas the larger dinosaurs get a little bit more behind their digging and can actually make deep traces that have a better chance of fossilizing.”
Prior to this finding, there was no definitive fossilized evidence that dinosaurs put on shows to attract attention from the other sex.
The discovery of the display arenas “fills in a crucial gap in our understanding of how dinosaurs actually behaved and lived, and interacted and bred, as living breathing animals that we would see running around today,” said Buckley.
“That whole process of courtship and mating is all soft tissue stuff (and so didn’t preserve), so there’s this big gap in the fossil record of like, well, how did they go about this?”
Buckley hopes similar display arenas, documenting the impressive performance put on to win over a female, can be found in the Peace Region.
“Since we have the same age of rocks, and the same types of dinosaurs roaming around the Peace Region, I think it’s only a matter of time before we start recognizing that type of fossil up here,” she said.