How Do Animals Protect Themselves from the Sun?

When those summer days get hot and sunny, remembering to wear sunscreen is essential! In one of our recent blog articles, we talked about how sunscreen works to protect our skin, but what do animals do? They are outside virtually all the time and, well, we can’t really expect them to wear sunscreen, can we? How do they protect themselves from those powerful UV rays? Read on to learn about how they have adapted with some nifty tricks!

Over the Skin and Under the Skin

The skin of many animals is protected by what we could call a coat that acts like a shield. Mammals have a thick coat of fur. Birds are covered by a variety of coloured feathers. Reptiles have scales that absorb UV rays.

Still, these shields aren’t perfect! Sunlight can still get through, and in any case, not every animal is wrapped from head to toe in fur and feathers. Some of their skin can still be exposed. So, how did they adapt to protect their skin? Some animals produce more melanin. Melanin is a natural pigment found in animal skin (including human skin) and is responsible for skin colour. Melanin also helps protect against UV rays. The more melanin in the skin, the better protected it is.

Ever wonder why a giraffe’s tongue is so dark? It has lots of melanin! Because giraffes use their long necks to grab food in high-up places, like tall trees, both their head and their tongue are exposed to lots of sunlight. This may explain why their tongues have so much melanin, for extra protection.

Do-It-Yourself Sunscreen

What’s an animal to do if they don’t have fur, feathers, or scales to protect their skin? Make their own sunscreen, of course! That’s right, the skin of some animals, big and small, can secrete substances that act as a sunscreen.

The hippopotamus uses a really neat trick! Thanks to glands found in their skin, hippos produce a reddish-pinkish liquid that oozes from their skin. It almost looks like blood, which explains why it is sometimes called “blood sweat.” This liquid is actually an oil that protects a hippo’s skin from the sun’s rays. It also stops the skin from wrinkling after a long soak in the water.

 

Then there’s an insect called the blue death feigning beetle (Absolus verrucusus). It secretes a kind of wax to protect it from the heat of the blistering desert sun. Did you notice their bright blue colour? This special wax is responsible for that too!

What about reptiles? Not only do they have scales to protect them, but they can also produce a compound called gadusol, which gives them added protection against UV rays. Gadusol is also produced by birds and some fish. In fact, a number of adult fish produce gadusol to protect themselves, but mothers also deposit gadusol into their eggs to protect their babies.

When All Else Fails, Change Your Habits

So, what do you do if you don’t have fur, feather, or scales, and you can’t produce your own sunscreen? Answer: smart habits!

Take elephants. They take mud baths and roll themselves in the dust to cover their skin and protect it. That’s one way to avoid sunburns!

 

For animals that don’t have their own sunscreen working for them, finding shelter is the next best strategy. Grabbing a spot in the shade, hiding underground, finding a cool spot to rest… all great ways to beat the heat especially when it really gets up there. All good tactics for humans too! So, don’t forget to think about sun exposure when you head into the outdoors this summer, and make sure you know how much sun is too much for you!

 

Nature is so ingenious and innovative. It is famous for its ability to adapt to the many challenges of life here on Earth. Learn more about all its surprises and secrets in Animal Kingdom 3D: A Tale of Six Families at the IMAX®TELUS theatre!

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