Speaker 1: Welcome to brain stuff from how stuff works, Hey, brain Stuff,
Speaker 1: Lauren vocal bomb here. Unlike most newborn creatures, elephants look
Speaker 1: geriatric right out of the womb, thanks in large part
Speaker 1: to their loose fitting, wrinkly skin. But elephants aren't manipulating
Speaker 1: the system to collect social security early. Their cracked skin
Speaker 1: is a clever evolutionary adaptation that protects these animals from
Speaker 1: the sun's intense rays. African bush elephants are pacaderms, a
Speaker 1: group of large animals like hippos and rhinoceroses. The name
Speaker 1: pacaderms is based on a Greek word that means having
Speaker 1: thick skin. These enormous, warm blooded animals can weigh around
Speaker 1: eleven tons that's about ten metric tons and measure up
Speaker 1: to about thirteen feet tall at the shoulder that's about
Speaker 1: four meters In short, it's a lot of flesh and bone,
Speaker 1: all baking in the often brutal African heat, and as
Speaker 1: it turns out, elephants can't sweat. Is it possible to
Speaker 1: perspire with sympathy? Recently, a team of researchers out of
Speaker 1: Sweden went more than skin deep in their studies of
Speaker 1: the pacader epidermis. Using both light and electron microscopes, along
Speaker 1: with intricately detailed computer modeling, the researchers were able to
Speaker 1: determine the cause of elephants scaly skin. For starters, the
Speaker 1: scientists found that the crackled appearance of elephant skin is
Speaker 1: not a sign of aging or skin shrinkage, as is
Speaker 1: often the case with other species. Rather, it is a
Speaker 1: purposeful design resulting from the stress of the skin bending.
Speaker 1: These cracks allow the skin to retain moisture and dirt,
Speaker 1: which reduces the harmful effects of the sun and prevents
Speaker 1: harmful swings in body temperature. The barrier also wards off
Speaker 1: some types of pests and parasites. Elephant skin, unlike human skin,
Speaker 1: is resistant to shedding, so the layers, particularly the super
Speaker 1: tough top layer, the stratum corneum, stick around longer before
Speaker 1: sloughing off. It also has a lot more keratin than
Speaker 1: human skin, so it's more durable, keratin being the stuff
Speaker 1: that makes up fingernails and is a small presence in
Speaker 1: our own skin. As this thick hide is subject to
Speaker 1: everyday movement like bending and twisting, it quickly wrinkles with
Speaker 1: layer upon layer of wrinkly skin serving as a complex
Speaker 1: system of channels the capture and hold moisture and dirt,
Speaker 1: so when you see elephants basking in sloppy pools spraying
Speaker 1: water in mud to and fro, they aren't just doing
Speaker 1: it for fun. The mud settles into the tense cracks
Speaker 1: in their skin, some of which are just a micrometer
Speaker 1: across about fifty times smaller than the naked human eye
Speaker 1: can detect. Continually wetted, the skin remains permeable, helping the
Speaker 1: animals stay cooler. And interestingly, elephant skin doesn't just randomly wrinkle.
Speaker 1: It cracks in geometric shapes that approximate other common sights
Speaker 1: in our world, from drying mud to heat shattered asphalt,
Speaker 1: or even geometrically precise rock breakage like the giants causeway
Speaker 1: in Ireland. The result is a durable cooling system that
Speaker 1: keeps these gigantic mammals from cooking in their own thick
Speaker 1: skin on steamy summer days. With their huge bodies and
Speaker 1: constant sun exposure, it would be easy to assume that
Speaker 1: elephants often fall victim to skin cancer and its side effects,
Speaker 1: but as it turns out, cancer is relatively rare in
Speaker 1: these animals, thanks in part to a gene called P
Speaker 1: fifty three, Elephant body chemistry identifies DNA abnormalities, and then
Speaker 1: Nix's cells that seem doomed to tumors. Scientists starts studying
Speaker 1: these so called zombie jeans to see how they might
Speaker 1: affect human biology too. Today's episode was written by Nathan
Speaker 1: Chandler and produced by Tyler Clang. For more on this
Speaker 1: and lots of other wrinkly topics, visit our home planet,
Speaker 1: how Stuff Works dot com