Glow-in-the-dark millipede sheds light on evolution of bioluminescence

They might be modest crawling organisms, but millipedes could actually hold the key to unlock the mystery of bioluminescence.

In a new study published in the Proceedings of the National Academy of Sciences, Paul Marek and Wendy Moore – entomologists from Virginia Tech and the University of Arizona, respectively – detailed the “rediscovery” of the Xystocheir bistipita millipede and realized that it actually glowed in the dark.

This phenomenon is called bioluminescence, or the ability of living organisms to produce light through internal chemical reactions.

Marek and Moore said  X. bistipita is actually related to the genus Motyxia, the only bioluminescent millipede genus in the Polydesmida order.

This realization prompted them to change the millipede’s name from X. bistipita to Motyxia bistipita, transferring it into the new genus.

“The discovery of bioluminescence in X. bistipita and its pivotal evolutionary location provides insight into repeated evolution of bioluminescence across the tree of life,” the study said.

Marek and Moore hypothesize that Motyxia’s ability to glow in the dark actually originally evolved as a way of coping with the metabolic stress of living in a hot environment.

Peroxide and other potentially harmful byproducts build up in the millipedes’ bodies because of the high temperatures.

According to the study, the process of bioluminescence uses these byproducts for the production of light, neutralizing them and keeping the millipede safe.

This ability was adapted later on by newer species as a method of warning potential predators about their toxicity.

It was previously thought that warning signals don’t evolve gradually in prey, but these findings suggest that it is possible if the warning originally served another purpose.

“I thought it was going to be just another boring day in the lab,” Marek told National Geographic, sharing how we were surprised at discovering that the formerly-named X. bistipita actually emitted a faint cyan glow.  — Bea Montenegro/LBG, GMA News