Science

Scientists are baffled by these 6 glow-in-the-dark animals

by Robin Bea
David Prötzel, Zoologische Staatssammlung München

David Prötzel, Zoologische Staatssammlung München

A group of German scientists recently discovered a species of gecko has a surprising, hidden talent.

Under UV light, the web-footed gecko glows a bright fluorescent green around its eyes and down its sides.

David Prötzel, Zoologische Staatssammlung München

David Prötzel, Zoologische Staatssammlung München

The scientists found guanine crystals sitting inside pigment cells called iridophores on the areas of the gecko that fluoresce.

David Prötzel, Zoologische Staatssammlung München

Iridophores are already well studied, and neither they nor guanine crystals are thought to directly cause fluorescence.

David Prötzel, Zoologische Staatssammlung München

It’s also a mystery what advantage these neon patterns might hold for the gecko.

The same researchers also found fluorescence in chameleons in 2018.
David Prötzel, Zoologische Staatssammlung München

In that case, thin, raised scales provided a “window” to view the fluorescent bones beneath.

David Prötzel, Zoologische Staatssammlung München

In most cases, scientists are unconvinced that fluorescence helps animals, though it could play a role in camouflage, mating, or communication.

Jonathan Martin, Northland College

Those are the leading theories as to why platypuses glow under UV light, as researchers from Northland College in Wisconsin found last year.

Jonathan Martin, Northland College

The same researchers found certain flying squirrel species glowed pink in UV light, too.

Dr. Kenny Travouillon, Western Australia Museum

Following these discoveries, members of the Western Australia Museum took a blacklight to the museum's collection, finding a bright glow in some unexpected creatures, including wombats.

And as if they weren’t creepy enough already, scorpions have long been known to glow under UV light, but no one is quite sure why.
McNeese State University

Lajos Endredi / 500px/500Px Unreleased Plus/Getty Images

One recently discovered fluorescent compound in scorpions could protect them from parasites.

Dr. Kenny Travouillon, Western Australia Museum

The more scientists look into it, the more common bioluminescence appears to be among the animal kingdom.

Oxford Scientific/Photodisc/Getty Images

The truly baffling questions are why animals evolved to glow this way in the first place — and, in many cases, how they manage to glow so brightly.

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