MEANING: Broad lizard
PERIOD: Late Triassic
CONTINENT: Europe
Plateosaurus is a basal sauropodomorph that lived during the Late Triassic period in what is now Central and Northern Europe. It was a bipedal herbivore with a small skull on a long, flexible neck. It had powerful hind limbs, short but muscular arms, and grasping hands with large claws on three fingers, possibly used for defense and feeding. Plateosaurus was one of the earliest described genera that is still used today, but due to its basal placement in dinosauria, it remains difficult to identify as a direct ancestor of later sauropods.
Plateosaurus is from the Triassic. The Triassic is a geologic period which spans from the end of the Permian Period 251 million years ago to the beginning of the Jurassic Period 201 million years ago. Both the start and end of the period are marked by major extinction events. The global climate during the Triassic was mostly hot and dry, with deserts spanning much of Pangea's interior. However, the climate shifted and became more humid as Pangea began to drift apart. Though it is the first period of the Mesozoic Era, the age of the dinosaurs, true dinosaurs didn't exist through most of it, finally evolving only in the Late Triassic.
Plateosaurus is a sauropodomorph. Sauropodomorpha is a group long-necked, herbivorous, saurischian dinosaurs that includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had long necks and tails, were quadrupedal, and became the largest animals to ever walk the Earth. The prosauropods, which preceded the sauropods, were smaller and often able to walk on two legs. The sauropodomorphs were the dominant terrestrial herbivores throughout much of the Mesozoic Era, from their origins in the Late Triassic until their extinction at the end of the Cretaceous.
Sauropodomorphs had a light, tiny skull on the end of a long neck and a counterbalancing long tail. These adaptations gave them access to high tree foliage. The earliest known sauropodomorphs were small and slender, but by the end of the Triassic, they were the largest dinosaurs of their time, and throughout the Jurassic and Cretaceous they continued growing. They were initially bipedal, but as their size increased they evolved a four-legged gait adapted only to walking slowly on land. The early sauropodomorphs were most likely omnivores as they were only recently diverged from the carnivorous theropods.