The hippopotamus is a large African herbivore that spends much of its day submerged
in rivers or lakes. It has several adaptations for life underwater. For example, when a
hippopotamus feeds underwater, bristle-like hairs that protrude from around the
mouth help the hippopotamus to detect food and other hippopotamuses. An adaptation
that allows the hippopotamus to communicate under murky water is its specialized
jawbone. Underwater sounds cause the specialized jawbone to vibrate, and these
vibrations travel from the jawbone to the middle ear.
25. When a hippopotamus is underwater, its jawbone conducts vibrations first to the
hippopotamus’
a. cochlea b. ossicles c. organ of Corti d. semicircular canals