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Why does a hippopotamus produce pink or reddish skin fluid?
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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.
The belief that hippopotamuses sweat blood is a myth; they do not actually sweat at all. Instead, numerous skin glands release an oily, reddish or pinkish substance often described as a "lotion." This secretion functions as a natural sunblock, effectively filtering out ultraviolet radiation to protect the hippopotamus while it basks in the sun.1