-potami or -potamuses 😉 More than one hippopotamus are called hippopotami, and ‘hippopotamuses’, or ‘hippos’ is also used. … A male hippo is known as a bull. A female hippo is called a cow, and a baby hippo is called a calf. A group is called a pod, herd, dale, or bloat.
The eyes, ears, and nostrils of hippos are placed high on the roof of their skulls. This allows them to breath and see while the rest of the body is submerged. They can hold their breath for up to six minutes underwater. When completely submerged, their ears and nostrils fold shut to keep water out.
The jaw hinge is located far back enough to allow the animal to open its mouth at almost 180°. The bite force of an adult has been measured as 8,100 newtons (similar to bench-press 825kg in weights!) and can easily snap a canoe in half with their powerful jaws, Hippos teeth sharpen themselves as they grind together. The incisors can reach 40 cm, while the canines reach up to 50 cm and are only used for combat.