Glowing Millipedes Revealed

Read about the new science behind glowing millipedes and why they give off light.

Discover the clues scientists have uncovered about why these creatures give off light.

Published June 1, 2015

Who knew night-lights could crawl? Millipedes are a type of tiny invertebrate, or spineless animal, that can each have hundreds of legs—and some species light up. In fact, the glow of certain millipedes is so bright it is enough light to read by. Now scientists think they’ve cracked the mystery of why some millipedes developed their glow.


How are certain millipedes able to light up? The animals produce special substances, called proteins, that give off a bluish green gleam from beneath the tough shell-like structure that covers their bodies. Scientists already knew that these creatures use their glow to tell predators such as birds to back off.

To find out more about the critter's brightness, scientists Paul Marek and Wendy Moore studied species of millipede that live in California's Sierra Nevada Mountains. Results revealed that the animals' bioluminescence—the ability to give off light—may have first developed not to fend off enemies, but to help them deal with California's hot, dry environment.


During their study, Marek and Moore examined millipedes from areas in the Sierra Nevada Mountains that have varying temperatures. They observed that species living at higher elevations where temperatures are cooler give off a brighter light than those living at lower, hotter elevations. The warmer the environment, the dimmer the millipedes glow. Marek and Moore believe that the proteins that help the millipedes light up also shield them from the harmful effects of overheating.

Scientists still have a lot to learn about these creepy-crawlies and their glow. But here’s one thing they do know: When it comes to being bright, these millipedes have a leg up.

Text from "New Glowing Millipede Found; Shows How Bioluminescence Evolved" by Carrie Arnold for National Geographic News

Adapted by Jessica Shea, NGS Staff