The name hippopotamus means “river horse”, which perfectly suits this species’ semi-aquatic lifestyle. Unlike what one could think, it moves underwater with ease and, once on the ground, it trots with unexpected speed. The hippopotamus’ skin is fragile and needs to be constantly moist. Its eyes, nostrils and ears are all situated at the top of its head, so he can stay alert and breathe while the rest of its body is fully submerged.