It is hard not to be fascinated with fireflies, as there does not exist many insect species that are capable of bioluminescence. The biological mechanisms that make bioluminescence in fireflies possible had long been considered a mystery among the most prominent scientists from past centuries. Now, the biology behind a firefly’s glow is well understood by entomologists and other scientists, but many average Joes remain in the dark concerning how such an odd phenomena could exist in nature. While insects may not seem sophisticated enough to make conscious decisions, entomologists believe that fireflies are in control of when their flashes end and begin.
The bioluminescent glows of a firefly result from a rather complicated biological process that involves an interaction between many bodily chemicals. First, oxygen mixes with calcium, adenosine triphosphate (ATP) and the chemical known as luciferin. When luciferin is added to the mix in the presence of the bioluminescent enzyme known as luciferase, a biological form of light is produced, hence the word “bioluminescence.”
The type of light that people are familiar with produces heat, as most people can tell you that a light bulb becomes very hot when left on. Bioluminescence, on the other hand, is a different type of light, as it does not produce heat. If bioluminescence did produce heat, fireflies would have become extinct pretty quickly. Fireflies produce “cold light,” which is a type of light in which energy is not released as heat.
According to Marc Branham, an assistant professor in the department of entomology and nematology at the University of Florida, a firefly controls the chemical reaction that produces their glow by adding oxygen to other chemicals which are required to produce light. Fireflies, and other insects, do not possess lungs; instead, they breathe oxygen through holes on their body called tracheoles. Fireflies glow for many reasons, some of which are unique to certain species. Generally, firefly larvae use their bioluminescent flashes to communicate distaste, while adults glow in order to identify members of their own species as well as to communicate during courtship.
Have you ever witnessed a group of fireflies glow in unison?