Hippopotamuses

Species	2 species
Diet	Herbivore
Length	9 ft 6 inches to 16 ft 7 inches
Height	4 ft 3 inches to 5 ft 5 inches
Weight	1.6 to 2.9 tonnes
Lifespan	40 to 50 years
Conservation Status	Vulnerable
Classification	Mammalia > Artiodactyla > Hippopotamidae
Habitat	Freshwater rivers and lakes, sometimes estuaries

Despite their name meaning “river horse,” hippopotamuses are viewed as closer in design to whales and dolphins. These three-ton giants spend their days beating the intense African heat by lounging in lakes and rivers, but they cannot actually swim or float; they are so dense that they walk or bounce along the riverbed instead. To protect their sensitive, hairless skin from sunburns and infections, hippos naturally secrete a bizarre, reddish-pink fluid nicknamed “blood sweat” that acts as a built-in sunscreen and antibiotic. At night, they emerge onto land to graze, acting as massive ecological lawnmowers.

Locations

Central and Southern Africa

Hippos love spending all day in the water, but they can’t actually swim or float! They are so heavy and solid that they sink to the bottom and run or bounce along the riverbed like astronauts walking on the Moon.
A hippo’s eyes, ears, and nostrils are sitting right on top of its flat head. This means it can hide its whole body underwater like a submarine while still peeking out to breathe and see what’s going on.
When a hippo goes to the bathroom in the river, it spins its flat tail around like a fast kitchen blender! This spreads the poop everywhere, which sounds silly, but it acts as a special fertilizer that feeds river plants and tiny fish.
Hippos sleep in the water all day to stay cool, but when the sun goes down, they climb onto land. They spend the whole night walking around in the dark, munching on grass like giant, hungry lawn mowers!

212	May 20, 2026	(North America)
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