A Game-Changing Discovery
Dr. Jakob Vinther from the University of Bristol’s School of Earth Sciences, along with the paleoartist Robert Nicholis and Dr. Diane Kelly, who is a specialist in copulatory systems and vertebrate penises from the University of Massachusetts Amherst, has now described the first cloacal vent region from a dinosaur with the size of a labrador with the name Psittacosaurus, comparing it to vent across modern vertebrate animals living on land.
Dr. Vinther shares that he noticed the cloaca years ago after they had reconstructed the color patterns of this dinosaur using a remarkable fossil on display at the Senckenberg Museum in Germany, which preserves its color patterns and skin.
It took them a long time before they got around to finish it off. The reason for this is that no one has ever thought of comparing the exterior of cloacal openings of living animals. They considered this to be largely unchartered territory. Dr. Kelly added that they are pretty nondescript. They found the vent does look different in many different groups of tetrapods; however, in most cases, it didn’t tell much about the sex of the animal.
The researchers note that the outer margins of the cloaca of the dinosaur are highly pigmented with melanin. They think that this pigmentation provided the vent with a special function in display and signaling just as with living baboons and some breathing salamanders.
Reconstructing the Dinosaur’s Features
Robert Nicholis said that as a paleoartist, he found it amazing to have the great opportunity to reconstruct one of the last remaining features we didn’t know about in dinosaurs. He thinks that knowing that at least some of them were signaling to each other gives the specialists the great freedom to speculate on a whole variety of how plausible interactions during dinosaur courtship. The doctors from the university consider this to be a whole game changer.