This is a citation of an outside article. Gravyday is not responsible for its content. Original URL below. This fossilized butthole gives us a rare window into dinosaur sex The cloaca is the hole-y grail to understanding prehistoric copulation. Dinosaur fossils can be, for lack of a better term, rather bare-bones—particularly in their delicate, easily-destroyed nether regions, which can fall prey to the ravages of scavengers, or an explosive release of postmortem gas. But after working with a dinosaur specimen from the Senckenberg Natural History Museum in Germany, Jakob Vinther, a paleontologist at the University of Bristol, returned and realized that its private parts were unusually well-preserved.(more)