1m

Mesosaurus was one of the first reptiles to return to the water where its amphibian ancestors originally came from. Its feet were webbed, body streamlined, and its long tail supported a fin. Since the hind legs were much longer, they are presumed to have been used to propel the creature through the water. Its body was flexible and could easily move sideways, but it could not turn as a result of highly thickened ribs (a feature also seen in modern sea cows).

Aquatic Insectivore

Brazil and Southern Africa

First fossil that proved continental drift