Hippos Sweat Their Own Sunscreen
You know that reddish fluid on hippo skin that turns brown? It’s not just funny colored sweat. Japanese scientists reported in Nature1 that it acts as a sunscreen and an antibiotic. See also the BBC News report on this finding.
1Saikawa et al., “Pigment chemistry: The red sweat of the hippopotamus,” Nature 429, 363 (27 May 2004); doi:10.1038/429363a.
It must have been a sight watching the Japanese timidly wipe the face and back of a hippo to get their samples. Wonder how many generations of hippos had to die of skin cancer to get this lucky set of mutations established in the population.