Hippopotamuses are among the largest living mammals; only elephants and some rhinoceroses and whales are heavier. Hippo’s can live in the water or on land. Their specific gravity allows them to sink and walk or run along the bottom of a river.
Hippos are considered megafauna, but unlike all other African megafauna, hippos have adapted for a semi-aquatic life in freshwater lakes and rivers.
Hippos measure 3.3 to 5.2 meters (11 to 17 ft) long, including a tail of about 56 centimetres (22 in) in length and average about 1.5 meters (5 ft) tall at the shoulder.
Just to lighten things up a bit, I just had to post this one, sound effects are added to the video.