Hippos Produce "Blood Sweat" From Their Pores
When the ancient Greeks observed "blood sweat" on the skins of hippos, they assumed that the substance was indeed blood. But modern analysis has proved that the secretion is made up of two pigments: red hipposudoric acid and orange norhipposudoric acid. Both pigments shield the hippo from sunburn, and the red pigment also has antibacterial properties. These properties are especially helpful after fights, which often leave hippos battered and wounded.
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Key Facts In This Video
According to the African Wildlife Fund, hippos kill nearly 3,000 humans every year. (0:51)
Hippos secrete a sticky crimson substance from their skin that acts as an antibacterial sunscreen. (1:36)
The hippo's closest living relative is the whale. (3:01)