Animals who live in warm climates spend most of their day under the unforgiving sun, so why don't they get sunburns? A lot of tropical animals have sunscreen built into their coats, which is lucky because rubbing sunblock on a lion's back is no fun. For these burn-resistant animals, it's all in the shape of the hair in their coats that matters. Cutting one of these hairs open length-wise reveals a triangular shape that's great at reflecting wavelengths on the visible end of the spectrum but also the near-infrared spectrum. This means that their hair is really good at letting them cool off.
That's just one of nature's coping mechanisms. According to a study published in Nature, the hippopotamus secretes its own sunscreen, which is extremely helpful for the subsaharan mammal. Zebrafish live in water, but they're still susceptible to sunburns. Research published in the journal eLife found Zebrafish can produce a chemical called gadusol which protects them against UV radiation.
It's probably just a matter of time before someone sells an "all natural" sunblock that came from a hippo! If it did, would you wear it?
Sunscreen confusion may burn shoppers (Science Daily)
"Consumers may need more help navigating the sunscreen aisle. A new study found that many people seem to be confused by sunscreen terminology. Only 43 percent of people surveyed understood the definition of sun factor protection (SPF) and only seven percent knew what to look for on a label if they wanted a sunscreen that offers protection against early skin aging."