As the sun sets on a Pangaean plain, about 200 million years ago, a solitary Plateosaurus finds itself outnumbered by a pack of theropod predators.
In one of the accompanying images to this one, Plateosaurus Herd, I mentioned that a dinosaur the size of Plateosaurus had very few natural enemies, as it was considerably larger than the carnivorous dinosaurs of the time. There were large predatory reptiles around, 'land crocodiles' called rauisuchians, but the theropod dinosaurs of the late Triassic were much smaller than the herbivorous prosauropods such as Plateosaurus. However, Plateosaurus and its relatives survived for a long time; into the early Jurassic period; and during that time, the rest of the dinosaurs were evolving to replace the other, more primitive reptiles (such as the rauisuchians) which had died out at the end of the Triassic. The carnivorous theropod dinosaurs were diversifying, and some of them, which started out as relatively small Triassic dinosaurs such as Coelophysis, were growing large enough to pose a threat to the prosauropods and early sauropods. The first giant theropod to appear was Dilophosaurus, a 6-meter predator with 2 large crests on its head. While there is no current evidence that Dilophosaurus itself and Plateosaurus overlapped in time or geography, its close ancestors probably did - and other, later types of prosauropod certainly did encounter Dilophosaurus So, in this scene, one of the last plateosaurs encounters a group of theropods which are clearly direct ancestors of Dilophosaurus, possessing many of its recognizable features... (Fortunately, my own Dilophosaurus model has morphs to change the size and shape of its paired crests, and can reasonably be used to represent an animal which is not quite a true Dilophosaurus, but its descendants will be...)
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