Ngorongoro, The Hippopotamus

The common hippopotamus (Hippopotamus amphibius) is a large, semiaquatic mammal, mostly herbivorous. After the elephant and rhinoceros, the common hippopotamus is the third-largest type of land mammal. Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, the closest living relatives of the Hippopotamus are cetaceans (whales, dolphins, porpoises, etc.) from which they diverged about 55 million years ago.