PLATEOSAURUS

genus of early dinosaurs known from extensive fossil material found in Europe and dating from the Late Triassic Epoch (230 to 208 million years ago). Plateosaurus, a representative of the prosauropods, an early group that might have been ancestral to the giant sauropod dinosaurs of later time periods, was among the earliest dinosaurs to attain a relatively large size. It grew to be about 7 m (23 feet) long and was more massive than earlier dinosaurs. The bones were no longer hollow since hollow bones could not support the increasing bulk of the animal. Although Plateosaurus could rise up on its two very strong hind legs, its forelimbs also were relatively well-developed and strong, and it most likely normally walked on all four legs. The small skull was perched atop a long and flexible neck and contained compressed and spatulate teeth serrated on the front and back edges. Although it has been suggested that Plateosaurus was carnivorous, the teeth and jaw musculature seem much better suited to a plant diet. It also has been suggested that Plateosaurus was at least partially aquatic, but this, too, is uncertain. Specimens that resemble Plateosaurus have been found in South Africa and China, and it is possible that the genus had a very wide distribution.