Beetles That Light Up

Recently, we looked into the secret behind glow-in-the-dark stickers. We learnt that we can use different synthesized pigments to create light in the dark. The question today is, how does mother nature do it?

What Makes Fireflies Glow?

Yes, Fireflies are beetles, they generally have soft bodies and can produce light at will.
Unlike glow-in-the-dark stickers that can be charged with light, fireflies have specialized organs that produce light by the help of a chemical equation. This type of light production is called bioluminescence. Below is the reaction that produces the energy:

Unlike light bulbs that produce a huge amount of heat when they are lit up, fireflies produce cold light, which is basically light without the heat. This is necessary because if the firefly gets heated during light production, it would lead to certain death.

A firefly controls the beginning and end of the chemical reaction, and thus the start and stop of its light emission, by adding oxygen to the other chemicals needed to produce light. This happens in the insect’s light organ. When oxygen is available, the light organ lights up, and when it is not available, the light goes out.

Fireflies appear to light up for a variety of reasons. Fireflies produce defensive steroids in their bodies that make them unpalatable to predators. Larvae use their glows as warning displays to communicate their distastefulness.
As adults, many fireflies have flash patterns unique to their species and use them to identify other members of their species as well as to discriminate between members of the opposite sex. Several studies have shown that female fireflies choose mates depending upon specific male flash pattern characteristics.
Higher male flash rates, as well as increased flash intensity, have been shown to be more attractive to females in two different firefly species.

Although the method of light production is a chemical one, it leads to widespread biological phenomena including sexual communications and aposematic signalling. “Living” chemicals that can thrive and reproduce, that’s nature for you.