Scientists learned of this ancient form of dino diddling from the discovery of Daspletosaurus horneri, a new species of the tyrannousaur family found in Montana. The D. horneri (which is the filthiest dinosaur name ever, by the way) remains revealed much about tyrannosaur biology, specifically its face, which was armored with scales and tough skin around the snout and jaws. Inside, however, scientists found holes called foramina, or openings for nerve endings. The nerve endings would have given the short-armed tyrannosaurs an extra appendage with which to feel their way around the jungle and, ehem, each other.
The lead scientist in the research, Dr. Thomas Carr of Wisconsin's Carthage College, drew a direct line from crocodiles and alligators -- who have similar organs -- to the tyrannosaurs. “Given that the foramina are identical in tyrannosaurs, [that] indicates that they had super-sensitive skin as well,” he said. Apparently modern crocs and gators do the same thing with thousands of tiny sensitive bumps in their jaws. They rub up on each other too in movements that one study said, “frequently result in what appears to be overstimulation.”