HABITAT AND DIET
Their nostrils close, and they can hold their breath for five minutes or longer when submerged. Hippos can even sleep underwater, using a reflex that allows them to bob up, take a breath, and sink back down without waking up.
Why do hippos sleep underwater?
They sleep under water.
Hippos can't survive for long out of water because their skin is extremely sensitive to direct sunlight, which is why they secrete a red, oily substance, once thought to be blood, that serves as both a sunscreen and an antibiotic.
Do hippos sleep on land or water?
Hippos can sleep underwater by using a reflex that allows them to breath and sink back down underwater without waking up.
