WEBVTT - FunStuff Playlist 01: Why Do Flying Squirrels Glow Hot Pink in UV Light?

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<v Speaker 1>Welcome to brain Stuff production of I Heart Radio. Hey

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<v Speaker 1>brain Stuff, Lauren Vogel Bomb here. It's amazing what you

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<v Speaker 1>can find if you shine a flashlight into your backyard trees.

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<v Speaker 1>Biologists in Wisconsin have made a rather startling discovery that way,

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<v Speaker 1>in part startling because it apparently hadn't been recorded until now.

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<v Speaker 1>Three different species of flying squirrels, specifically Southern, Northern, and

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<v Speaker 1>Humboldts flying squirrel which are found across North America and

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<v Speaker 1>into Central America, sport light brown fur that, when spotlighted

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<v Speaker 1>with ultra violet illumination, lights up a hot bubblegum pink.

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<v Speaker 1>The phenomenon occurs on both the top and bottom surfaces

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<v Speaker 1>of the flying squirrels, though it's the underside of a

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<v Speaker 1>flying squirrel's carriage, including the flaps of skin that's spread

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<v Speaker 1>out when the squirrel glides from tree to tree that

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<v Speaker 1>really glows. Jonathan Martin, a biologist at Northland College in Ashland, Wisconsin,

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<v Speaker 1>made the discovery in the forest one evening just by

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<v Speaker 1>shining a UVY flashlight into the tree canopy. He was

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<v Speaker 1>looking for lichens, which are certain types of frogs and

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<v Speaker 1>flora that light up in UVY light. That's when he

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<v Speaker 1>heard the chirp of a southern flying squirrel. As the

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<v Speaker 1>squirrel glided by, he shined the UVY flashlight on it,

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<v Speaker 1>and he saw a flash of fuchia. Martin and his

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<v Speaker 1>colleagues soon found themselves examining the skins of flying squirrels

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<v Speaker 1>at the Science Museum of Minnesota and the Field Museum

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<v Speaker 1>in Chicago. They took photos of the skins under visible

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<v Speaker 1>light and ultra violet light. All but one specimen of

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<v Speaker 1>the gliders glowed a pink that has been variously compared

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<v Speaker 1>to bubblegum, day glow, and licro from the nineteen eighties.

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<v Speaker 1>The results of the study were published in the January

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<v Speaker 1>twenty nineteen issue of the Journal of Mammalogy. The pink

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<v Speaker 1>is caused, the researchers say, by the furs fluorescence, which

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<v Speaker 1>is what happens when light is absorbed in one wavelength

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<v Speaker 1>and emitted in another. You may remember an episode we

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<v Speaker 1>did about how scorpions floresce bright green and ultraviolet light.

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<v Speaker 1>Some birds also have this trait, some fish too. Few

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<v Speaker 1>mammals do, though. Flying squirrels are nocturnal and are most

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<v Speaker 1>active at dusk and dawn. No other squirrels in North

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<v Speaker 1>America are known to possess this ability to fluoresce, including

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<v Speaker 1>tree squirrels like the Eastern gray, though there are over

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<v Speaker 1>two hundred and fifty squirrel species around the world, and

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<v Speaker 1>to be fair, the researchers have not yet tested other

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<v Speaker 1>species for the next question is what purpose could this

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<v Speaker 1>fluorescence serve. Humans can't see ultraviolet wavelengths except under special lighting,

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<v Speaker 1>but other animals can. One theory suggests the pink is

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<v Speaker 1>used to confuse owls, which, as it turns out, also

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<v Speaker 1>have undersides that fluoresce. A similar pink. Owls prey on

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<v Speaker 1>flying squirrels, among other mammals. Perhaps the squirrels evolved to

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<v Speaker 1>mimic owls so as not to be eaten by them.

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<v Speaker 1>Another theory, which is already being challenged, is that the

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<v Speaker 1>pink attracts potential mates. Flying squirrels have mating seasons, but

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<v Speaker 1>their flamboyant fluorescence is available for view it in year round. Anyway,

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<v Speaker 1>it's not even clear that squirrels can see in UV wavelengths. Ultimately,

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<v Speaker 1>the researchers point out that age old impetus of science.

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<v Speaker 1>This is proof of how much we don't know and

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<v Speaker 1>still need to learn. The study concluded the ecological significance

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<v Speaker 1>of this trait warrants further investigation. Today's episode was written

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<v Speaker 1>by Jamie Allen and produced by Tyler Clang for iHeartMedia

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<v Speaker 1>and how Stuff Works. For more on this and lots

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<v Speaker 1>of other topics, visit our home planet, how stuff works

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<v Speaker 1>dot com. Brain Stuff is production of iHeart Radio. For

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