Hippos are the third largest land mammal species on Earth, after elephants and white rhinos. Hippopotamuses are found in Africa. The name Hippopotamus means ‘river horse’. Their skin color varies from brown to grayish purple, and they’re almost completely hairless. Their ivory canine teeth grow continuously, and reach 20 inches in length. Hippopotamuses have short legs, a HUGE mouth and a body shaped like a barrel. A male Hippo is called a bull, and a female hippos is called a cow. These mammals are good swimmers. They have membranes that are between their toes that turn their feet into flippers, and fat beneath their skin helps them float in rivers and lakes. Adult Hippos can hold their breath underwater for up to six minutes.