Hippopotamus amphibius, photographed at the Philadelphia Zoo.

Have you ever tried to walk along the bottom of a pool while fully submerged? It isn’t easy. Keeping your feet on the bottom is enough of a task, and you would probably need a weight belt to take an underwater stroll. Hippos (Hippopotamus amphibius), though, walk and even prance along the bottom of lakes and rivers with ease. How do they do it?

When compared to a whale or even a manatee (the latter of which I will address a bit later on) a hippo does not look especially well-adapted to life in the water. It has a low, squat body and lacks a broad tail, flippers, or any other