Did hippopotamuses really sweat blood?

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A hippopotamus stands at the edge of a watering hole, with several other hippos partially submerged in the water, surrounded by green vegetation in Botswana, Africa. — hippopotamus The word *hippopotamus* is Greek for “river horse,” which reflects their behavior: they are often seen basking on the banks or sleeping in the waters of rivers, lakes, and swamps across Africa. They favor shallow areas where they can sleep half-submerged, though these places can become quite crowded—as many as 150 hippos may use one pool in the dry season.

No, hippopotamuses do not sweat blood. The belief that they do is an ancient myth stemming from the animal's unique skin secretions.

While hippos do not possess sweat glands, they have numerous skin glands that release an oily, reddish or pinkish substance. This secretion functions as a natural sunblock, protecting the animal by filtering out harmful ultraviolet radiation. Because of its distinct color, this "lotion" is often mistaken for blood by observers.1