© Dino Pulerà

Tyrannosaur’s sensitive skin may have helped it capture prey

In the twilight of the Age of Dinosaurs, tyrannosaurs were the apex predators. The bipedal carnivores spanned the globe for 14 million years in the late Cretaceous era, and fossils from Mongolia to North America offer scientists today a wealth of data on their biomechanics, anatomy, and evolution. But a fossil representing a new tyrannosaur species, dug up in Montana, may help show their sensitive side. The species, dubbed Daspletosaurus horneri (in honor of paleontologist Jack Horner), lived about 75 million years ago and stood about 2 meters tall and 9 meters long from snout to tail (about the length of a city bus). Because the skull and jaws of D. horneri were so well preserved, the team was able to study in detail its coarse, complex textures and determine what sorts of soft tissue once covered its face, they report online today in Scientific Reports. Their analysis suggests that tyrannosaurs’ faces were covered with flat scales, similar to modern-day crocodiles. And like those crocs, the tyrannosaur skulls have an array of holes within the bone; in the modern reptiles, nerves and blood vessels pass through those holes, transmitting sensory information from the facial skin. That sensitive skin, the authors suggest, may have given tyrannosaurs a leg up when it comes to identifying and capturing prey.