Brief explanation of hippos and their characteristics Hippos are large semi-aquatic mammals native to sub-Saharan Africa. They are the third-largest land mammal and can weigh up to 4,000 kilograms. Hippos have a distinctive appearance, with a barrel-shaped body, short legs, and a massive head with a wide mouth and large teeth. They are primarily herbivorous, grazing on grasses, but also consume some fruits and aquatic plants.