Joan Cartan-Hansen, Host: Humans aren't the only ones with skin.

Mammals, fish, birds and amphibians have skin too.

But some animals' skin has special properties that human skin doesn't.

[MUSIC] Cartan-Hansen: Harry Peachey is the curator at Zoo Boise.

If you ask him which animals have unusual skin, he'll start with the lions.

Harry Peachey, Curator, Zoo Boise: The skin there plays a role, an important role in combat, when lions interacting with one another, they sometimes interact aggressively.

That skin is very, very thick and it's designed to withstand those blows that come from other lions.

The hair on a lion's skin also plays a specialized role.

I think we all recognize that male lions have a very thick mane.

It's not really that involved in maintaining a proper body temperature or protecting from heat or cold, but it does protect from other lions.

Female lions also have a mane, but it's the same color as the rest of the hair on their skin, and it usually is not very thick.

But if you look closely at a female lion, sometimes you will see that mane.

Zebra skin is one of those skins that I think everybody recognizes.

I think everybody has probably asked the question at some point, is a zebra black with white stripes, or is it white with black stripes?

The typical answer is the zebras are white with black stripes.

The reason that people have settled on that answer is because if you look at a zebra and you look in particular at the belly on most of the different species of zebras that is all white.

The stripes actually serve a couple of different functions, in general its part of camouflage.

And if you see zebras, typically zebras are running in a group with other zebras.

If a predator comes along and wants to, to catch a zebra, those stripes make it very difficult for a predator to settle on an individual animal.

It also makes it hard for a predator to judge distance in daylight.

Uh, those stripes, the contrast between the black and the white will make it difficult for a lion, for example, to determine if a zebra is 70 feet away or 120 feet away.

fur of many mammals, reptiles have skin more like armor.

Peachey says one reptile's skin stands out.

Peachey: Crocodile skin actually is, is very unusual, and very specialized.

They have some unique features that you won't find in very many, if any, other species.

The skin obviously looks different.

You can see a lot of structure in the skin that is unique to crocodiles and alligators.

But the skin is able to do things like detect, magnetic impulses, uh, electrical impulses.

Cartan-Hansen: And unlike human skin which is generally smooth, crocodile and alligator skin is not.

Peachey: The bumps you see on the now crocodile skin are referred to as scutes.

And those are part of that, advanced, very specialized ability they have to detect changes in differences in their environment.

In addition to detecting things like the difference in saltwater and freshwater, they also are very sensitive to vibrations.

And also in this may be obvious to most people, a Nile crocodiles skin is waterproof.

It's an advantage for them as a living creature, but it's kind of a disadvantage in the long run because that attracted people to hunting alligators, capturing alligators and crocodiles and using their skinr shoes.

We are now by our Olive baboon habitat.

One of the things that you'll notice right away about baboons' skin is that bare area that has no hair.

It's a callus.

It's referred to as a callosite and that's a very thick patch of skin.

There are no nerve endings there, so they don't feel things with that.

This actually serves a couple of purposes.

One is, if you look at the baboons in the exhibit here, you'll see that they might be sitting on a wide variety of different surfaces, which if they didn't have this callosite would be very uncomfortable.

But the other thing it does is it serves as a communication aid.

So, a female baboon, for example, can communicate her willingness to interact with a male by the color of those callous sites.

When they turn pink or even red, that's an indication to a male that that's a female that might be ready to reproduce.

Cartan-Hansen: Our last stop on this animal skin tour is at the Southern Ground Hornbill.

Peachey: When you think of birds, you think of feathers before you think of skin, but, uh, there is a feature that's very obvious on a Southern Ground Hornbill that is made up of skin.

And that is that red patch on the throat that goes up on the side of the head.

That bag, if you will, on their throat is referred to as a wattle.

And it's involved in communication.

They use that to produce and amplify sound.

That red skin on their face that is attached to that wattle, kind of an extension of that skin, is actually an adaptation that helps with the Southern Ground Hornbills when they are feeding and hunting.

As the name implies, they spend a lot of the time on the ground.

They will dig for insects.

So, they take that long beak and they will Peck on the ground.

And that throws up not only insects, but bits of dust and dirt, that skin around the eye, it projects a little bit, it reduces the amount of dirt that might accidentally end up in their eyes.

Cartan-Hansen: Animals instinctively know to care for their skin.

Some get clean.

Some get dirty.

Some just chill in the shade.

Zoos like Zoo Boise even design their animal environments with skin care in mind.

Pools, landscaping.even special ramps, like this one for the crocodile, are all to help animals stay happy and alive.

Peachey: Since we all have skin, sometimes we'll take it for granted, but it's important to realize that without skin we would not survive a number of the things that our body has to do in order to keep us healthy are dependent on the presence of not just skin but healthy skin.

Cartan-Hansen: If you want to learn more about skin, check out the science trek website.

You'll find it at science trek dot org.

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