With a name like that, Tetraceratops would he expected to appear among the ceratopsian dinosaurs of the late Cretaceous. However, it was a big synapsid reptile that carried four horns on its head, so hence its name. Its position in the pelycosaur family tree is unclear, but current thinking is that it was a sphenacodontid related to Dimetrodon. It probably lived in upland areas far from the swamps where the pelycosaurs lived. This would explain why so few fossils have been found. Dinosaur costume for sale
Features:All we know of Tetraceratops is a single skull. This has features that show it to have been a meat-eating synapsid, but the nature of its preservation, in a particularly hard piece of ironstone, makes it difficult to examine. At first it was thought to have been an early gorgonopsid, one of the advanced mammal-like reptiles, and even now scientists are unsure of its actual affinities. mechanical dinosaur
Among all these big reptiles it is possible to lose sight of the fact that many of them were quite small animals. One in particular. Eudibamus. was about 26cm (10in) long, and found in Germany in 1993, but not scientifically described until 2000.
It looked rather like a little lizard, but its front legs were small and weak and the hind legs more than one and a half times their size. This, and the alignment of the hip. knee and ankle joints, led researcher Robert Reisz to speculate that Eudibamus ran on its hind legs, as many of the later reptiles did. This would make it the earliest reptile to do so. As Eudibamus was unrelated to any of the later bipedal dinosaurs it shows that bipedality is one of those features that evolved independently several times.