Hippopotomidae (Sub-family of Artiodactyla)

Hippopotomidae, from Greek ἵππος (híppos, “horse”) and Greek ποταμός (potamós, “river”), means “river horse”, in reference to the fact that all the members of this family are semi-aquatic animals that have a shape similar to that of other terrestrial quadrupeds (other artiodactyla), such as the horse.

Common names of members

Pygmy hippos, common hippos.

Distribution

Sub-saharan Africa.

Size

They are large animals, varying in size from 75–100 cm high at the shoulder, 150–175 cm in length and 180–275 kg in weight to 1.30 to 1.65 m tall, 2.90 to 5.05 m long and 1,500 kg.

Morphology

They have hourglass-shaped skulls with long snouts, barrel-shaped bodies with short tails and legs. Their strong bones and low center of gravity enable them to sink and move over the water's bottom thanks to their graviportal skeletal structures, which are designed to support their massive weight. Their toes are webbed, and their legs are short. Their eyes, small ears and nose are located at the top of their head. On the lower jaw, the tusk-like incisors and canines grow continuously. Their skin is thick with little hair. The skin is covered by a blood sweat which is reddish pink.

Ecology & Habitat

Although males can be found in very limited numbers in more fast waters with rocky slopes, they prefer rather quiet waters with gently sloping beaches. Semiaquatic, they need enough water to submerge themselves.

Diet

As herbivores, they mostly eat grass and very little aquatic vegetation.

Reproduction

They mate in the dry season and give birth in the wet season. Females give birth to one young. Newborns can dive for 40 seconds. For the first few days, the mothers will take care of the newborns without eating. The nursing period is around 8 months.