This early whale was well suited to life at sea. But it also lived on land. An ancestor of the right whale, Maiacetus lived 49–40 million years ago. It had flipper-like limbs and webbed feet, like modern seals. But it also had ankle bones—clues that although Maiacetus swam, its ancestors walked. As later whales evolved to become more aquatic, the telltale anklebone disappeared. Find more about ancient ocean predators at Who's on Top? Learn more about ancient whales on our Paleobiology Blog.