Hippopotamus sweat is red!

You can only imagine how many times people have thought these creatures were bleeding when it was just a hot day! Shortly after a hippo perspires, its sweat turns red because of unusual red and orange pigments that are secreted with it. Molecules within this pigments have been shown to absorb ultraviolet light, so the secretion works as a natural sunscreen! The substance is also rather acidic and demonstrates antibiotic properties.
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