The the most effective sunscreen on the planet is found in the the sweat of the hippo:
This natural skin-care product not only protects the hippo from the sun, it also regulates temperature and discourages the growth of bacteria. Professor Hashimoto and his colleagues collected samples of the hippo’s sweat and examined it, to see what makes it so special.They found it is made up of two pigments – one red, called “hipposudoric acid”; and the other orange, called “norhipposudoric acid”.
‘Collected samples of the hippo’s sweat’? I wonder how many grad students were lost in that escapade. Bonus fact: Hippos are the most dangerous animal in Africa, killing more humans than all of the other animals combined.