Fossils from a relative of the ferocious Tyrannosaurus rex led scientists to a fascinating conclusion recently: these powerful beasts had snouts with scales as sensitive as human fingertips.The ancestorThe Daspletosaurus horneri lived about 75 million years ago. Its bones were discovered in 1989, and scientists say it appears the animal is an ancestor of the Tyrannosaurus rex. The Daspletosaurus, which was smaller than T. rex at about nine metres long and two metres tall, died off more than 10 million years before the T. rex appeared. Scientists believe the Daspletosaurus horneri, which means “Horner`s frightful lizard,” had something in common with all tyrannosaurs — many small, sensitive nerve openings in its snout.The bonesThe fossils of the Daspletosaurus horneri — initially a piece of the snout, and later a complete skull and other specimens including a skeleton — were found in northwestern Montana and southern Alberta by American paleontologists. Among them was a team working under the auspices of Montana’s Museum of the Rockies. The remains were found in the same geological layer, the Two Medicine Formation, a deposit dating back to the late Cretaceous period, about 65 million to 145 million years ago.Into the grooveBased on research that flowed from the discovery of the Daspletosaurus horneri fossils, scientists found grooves and canals left by blood vessels and nerves in the snout area. From this, experts have deduced that these animals had a network of very sensitive nerves that would have connected to the scales of their snout. “Its surface tissue would have been like the human hand, very tough but sensitive, likely more so,” says one of the experts, Jayc Sedlmayr, an assistant professor of cell biology and anatomy with the Louisiana State University Health Sciences Centre.Similar creaturesA key to the research is anatomical similarities between dinosaurs and their two most common living relative ...
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