Unlike the amphibians, reptiles were able to exploit all the available food sources and many of them adopted a vegetarian diet. These reptiles were not dinosaurs, but many looked like the dinosaurs that would follow.
Carnivorous reptiles developed with long fangs to stab and tear their prey. These animals were lightly built and fast moving in order to hunt. Other were herbivores, developing teeth capable of grinding vegetation and huge barrel-like bodies to contain the massive digestive system needed to cope with a vegetable diet.
Although some of these reptiles looked like the dinosaurs, scientists know from studying the structure of their hip bones and limbs that most would have been more clumsy when walking or running.
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