While hippopotamuses and rhinoceroses may look similar, they are very different creatures. Hippos spend much of their time in slow-moving rivers. Rhinos, depending on their species, live in grasslands, floodplains, swamp... More »

There are only two species of hippopotamus in the world today. There are an estimated 125,000 to 150,000 common hippopotamuses in the world. Pygmy hippo numbers are even fewer, and there are an estimated 2000 to 3000 rem... More »

Hippos are endangered mainly because poachers hunt them for their meat and the ivory in their teeth. Other threats are habitat loss due to the encroachment of human settlements and the diversion of river water for agricu... More »

Baby hippopotamuses, which are more commonly known as calves, are born underwater and typically weigh in somewhere between 50 and 110 pounds and are about 4 feet long at birth. Because they are mammals that are born unde... More »

The larger of the two hippopotamus species can weigh up to 4,500 kilograms, or 9,912 pounds, and can measure over 16 feet long. The pygmy hippopotamus is much smaller, with a maximum weight of about 275 kilos, or 605 pou... More »

Although they spend much of their time in the water, hippopotamuses are one of the few animals unable to swim. Their inability to swim is partially due to their density. Instead, they walk or gallop along the bottom of t... More »

Large animals, such as whales, elephants, rhinoceroses, hippopotamuses, okapi and giraffes, use infrasound. Infrasound a frequency below 20 Hz that humans cannot hear, but several species of animals can produce and react... More »