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Plateosaurus skeleton

The most popular and best known dinosaurs are from the Jurassic and Cretaceous periods of geologic time, but dinosaurs date back 20 million years earlier to the Late Triassic. Plateosaurus and its prosauropod relatives were among the very first plant-eating dinosaurs to proliferate across the world and begin the160 million- year Age of Dinosaurs. Prosauropods fossils are found on every continent including Antarctica. At the same time that Plateosaurus prospered, we see the emergence of turtles, crocodiles, pterosaurs (flying reptiles), pleisosaurs (long-necked marine reptiles) and mammals. It was a time of change.

Plateosaurus was one of the largest of the Triassic dinosaurs and grew up to 8 meters long. While often depicted as bipedal, it was primarily a quadruped that could walk and stand on its hind legs if necessary. It had the fundamental body shape that would be exploited by the giant sauropods of the Jurassic: small head; long neck; long tail; and massive hind limbs. In fact, the disappearance of Plateosaurus and the other prosauropods from the fossil record coincides with the rise of the Jurassic sauropods.

Location
Plateosaur fossils are found in the Upper Triassic sediments of western Europe and it is one of the best known prosauropods. In Germany, paleontologists have even found mass death assemblages of plateosaurs which have contributed greatly to our understanding of this animal. The many complete skeletons recovered have been invaluable to our understanding of early dinosaurs. It is one of the largest of the prosaurodpods and among the largest of all the early dinosaurs. The prosauropods were the first plant-eating dinosaurs to achieve global distribution and also, were the first major group to go extinct.

Taxonomy
For many years prosauropods were considered ancestors of the giant sauropods such as Diplodocus and Camarasaurus, but current research shows that prosauropods had enough unique features that they should be considered close relatives, but not ancestors of sauropods. The connecting link between them has not been identified.

The taxonomic relationships of dinosaurs are a complicated arrangement full of long Greek and Latin words. This complex system helps us understand which dinosaurs are related to one another as well as the characteristics they have in common. The systematics of a specimen tell the story of its lineage and evolutionary relationships. Sauropods and prosauropods are grouped together as Sauropodomorpha and then grouped with theropods as saurischians.
Within the prosauropod group, most specimens, including Plateosaurus, fall into the Anchisauridae family.

Plateosaurus was characterized by several noteworthy features. We've already mentioned its small head, long neck, long tail body shape. In addition, it was large and robust, a harbinger of things to come. Its teeth were numerous and coarsely serrated, and the offset in the jaw structure allowed chewing similar to that of many modern mammals. The first (inside) finger of the front foot (hand) had a large claw, while the first and fifth digits on the hind foot were reduced. The middle toes bore most of the animal's weight.

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