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The Kid Should See This

Why Are Scorpions Fluorescent?

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Scorpions fluoresce—they glow a bright green color—in ultraviolet light, “such as an electric black light or natural moonlight.” Professor Carl Kloock of Cal State Bakersfield has around six ideas as to why.

In this sponsored Veritasium video, Derek Muller heads into the desert at night to talk about some of Kloock’s hypotheses—proposed explanations “made on the basis of limited evidence as a starting point for further investigation”—and learns about the experiments Kloock created to test them. Along the way, they catch a few of these glowing arachnids for a closer look.

testing how a scorpion attracts food
Is the ability to fluoresce a relic trait? Does the glow attract prey at night? Is it communication? Is it camouflage?

“And then there have been some other [hypotheses] that are a little bit more out there. One of which, being the one that I actually settled on at the end, is that they use it as part of their sensory system to detect the presence of light in the environment.”

Are they a kind of photon detector? Watch Why Are Scorpions Fluorescent? The sponsored message begins at the 9m30s mark after the content.

catching a scorpion
Related photos at Wired: Luminous Beauty: The Secret World of Fluorescent Arthropods.

Watch more videos about scorpions and fluorescence:
• Scorpions of the Bay Area
What’s on the belly of a scorpion?
• How can glowing poop help bat conservation?
• Slow Life: Incredible macro video of fluorescing corals & sponges
• The Difference Between Bioluminescence and Fluorescence

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