We know surprisingly little about dinosaurs that lived in the tens of millions years ago. However, this does not change the fact that they leave behind plenty of bones to be largely found, studied and made informed estimates of them.

Dinosaur fossil from China offers new clues

Today, the most durable and long-lasting remnants of dinosaurs are hard bones, while soft tissue is a very difficult situation to obtain. As a result of this situation, it was a great difficulty to understand more complex behaviors such as mating. But a recent new fossil from China is leading scientists to new information on dinosaurs. The fossil offers clues to how dinosaurs defecated and multiplied.

In a paper published in Current Biology, the research team studying the fossil from China explained that its soft tissue provided rich details about the back part of the dinosaur. In addition, the research team determined the openness with which the fossil and the dinosaur urinate, defecate and possibly mat. This singular opening is known as cloaca and is common in birds, which are the closest living relatives to dinosaurs today.

Explaining the research, dr. Jakob Vinther, lead author of the study, said, “I noticed the cloaca a few years ago after re-forming the color patterns of this dinosaur using an extraordinary fossil on display at the Senckenberg Museum in Germany. It took us a long time to finish because no one cared about comparing the outside of the cloacal openings of living animals, so it was largely uncharted territory,” he said.

In this case, the cloaca of the dinosaur species in question is a Psittacosaurus, showing that animals have a singuler openness for bodily functions and reproduction, but probably do not mat as birds do today. Modern birds mate by pressing their cloacal openings together, but this was not possible for dinosaurs. This means that males of the species have hidden penises in their cloacas.

Unfortunately, in the openness of the fossil, the organs in it are unprotymsed, making it impossible to know if this particular animal is male or female.

There’s still a lot unknown about how dinosaurs reproduced. This discovery is considered a single data point that represents only one type from a single point in time. Researchers think that as more fossils begin to tell a clearer story of how dinosaurs lived, one day there might be a better idea of what dinosaur mating looked like and how different species did it.