Hippo snorting in the water.
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A hippo spends most of its life in the water, and its body is well-suited to a liquid lifestyle. Blubber makes the animal buoyant, so it can float. And its skin oozes a pink “slime” that protects the hippo from sunburn, both in and out of the water.
The hippo’s head is also well adapted for aquatic life. Its eyes sit on top of the head, so the hippo can get most of its body under water and still see what’s going on above water. The nostrils are also located on top of the muzzle so the hippo can stay mostly under water and still breathe and sniff the air. When the hippo submerges, the nostrils close to keep out water.
The ears sit high on the head, so the hippo can still hear what’s going on above water when it’s mostly underneath. If the whole head goes under, the ears swivel to shake out water when the hippo resurfaces. But what about sounds below the water? That’s a job for the hippo’s jawbone, which conducts sound waves. So a hippo with its jaw submerged can hear sounds above and below water at the same time!
And one more way a hippo is adapted for life in the water: it can hold its breath for up to five minutes.