ShmoopTube

00:03

[Dino and Coop singing]

00:13

We've been bumping up against UV radiation quite a lot in this unit. [Man knocks a lamp off a table]

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Which…sounds pretty dangerous, actually…

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Well, as long as no one grows a second head during the course of this video, we should [A second head appears out from the mans neck]

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be okay.

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Anyway!

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UV radiation, also known as UV light, is a form of electromagnetic radiation with a frequency [Coop pointing at a blackboard]

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that's slightly higher than good ol' visible light.

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So maybe it's time we turn the spotlight on UV radiation. [Crowd cheering]

00:35

…Well…hypothetically.

00:36

It's invisible, so a spotlight won't help us see it or anything, but…you get the idea. [Spotlight searching around an empty stage]

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UV radiation is probably most famous for its association with the sun.

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Along with lots of other kinds of radiation, the sun beams UV radiation at our planet, [Different types of radiation being emitted from the Sun]

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which can be both a blessing and a curse. [UV rays hitting the Earth]

00:52

It's a blessing if you like getting a tan.

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The UV rays darken the melanin in human skin, which gives the body protection. [UV rays hitting an arm]

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But it's a curse if you try to tan for too long.

01:00

Exposure to too many UV rays for too long means you're in for a nasty sunburn, and that's

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never a good look.

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No matter how much red might be "your color." [Guy in a Santa costume on a beach]

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UV light comes from more places than just the sun, though.

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If you've ever played laser tag, you've probably been in contact with black lights…y'know,

01:15

those weird lights that make whites really bright and give your teeth a spooky glow.

01:19

Yup, black lights emit UV light, too. [Kid smiles and his teeth are glowing]

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And even though UV light is beyond the range of human sight, that doesn't mean it's invisible [Dino pointing at a blackboard]

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to everyone.

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Insects, for instance, have no problem seeing UV light. [Insects flying around a UV light bulb]

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And sure, it might be kind of embarrassing knowing that insects can do something that [Fly is swatted]

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you can't, but look on the bright side!

01:35

Humans are still the only species capable of dancing on rollerblades. [Girl dancing while rollerblading]

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For now, at least…clever insects… [Ant wearing rollerblades]

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Insect's ability to see UV light isn't just a nifty party trick.

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A lot of flowers have evolved nectar guides, which are patterns that help guide pollinators [Coop pointing at a blackboard]

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to their sweet, sweet rewards.

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Some of these patterns are visible to humans…

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…but some of them are completely invisible to us unless we're using a black light. [A black light reveals patterns on a flower's petals]

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However, those UV-fluent bugs can follow these flowers' signals without any trouble, or black [Bee flying to a flower]

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lights.

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Which is good, because it would take a lot hours at the gym for an insect to lug around [Group of bees carrying a black light bulb]

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a black light.

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Unfortunately for insects, their ability to see UV light can be used against them. [They drop the light bulb]

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The bulbs inside bug zappers are special UV light bulbs. [Someone swats an insect on their arm]

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The light attracts the bugs closer and closer… [Insect flying into a bug zapper]

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…until ZAP!

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No more bug.

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…Yeah, we guess we're not actually that jealous of them anymore. [Guy rollerblading past the smashed light bulb]

02:21

We'll take pride in our sweet rollerdance moves. [Guy rollerblades into a group of insects and falls over]

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