The Science Behind Fireflies: Five Fast Facts

What makes fireflies light up?

Running around the backyard catching fireflies, or lightning bugs, is a favorite summer pastime for many of us across New England. The glow from these insects can add to the beauty of any summer night.

But other than being nice to look at, what else do you know about fireflies? Many people aren’t aware of the science behind these pretty bugs. Here are five fast facts about the science behind fireflies to keep you “enlightened.” 

The Science Behind Fireflies

They’re Not Actually Flies.

Fireflies are actually beetles! They are nocturnal members of the Lampyridae family, which comes from the Greek word Lampein, meaning “to shine.” Most fireflies are winged, which distinguishes them from their cousin, the glow worm. 

Fireflies are masters of efficiency.

Although more than 2,000 species bear the name “firefly,” not all fireflies glow. Those that do mix oxygen with a pigment called luciferin to generate light with very little heat. The enzyme luciferase acts on the luciferin in the presence of magnesium ions, a chemical called adenosine triphosphate (ATP) and oxygen to produce light. The light that some fireflies produce is extremely efficient. In fact, it’s the most efficient light in the world! Nearly 100% of the chemical reaction’s energy becomes light. 

the science behind fireflies: firefly on blade of grass
In the daylight, fireflies look more like regular old beetles!

Fireflies can be romantic… sometimes.

Fireflies flash in patterns that are unique to each species. Each blinking pattern is used to help them find potential mates. Male fireflies typically fly through the air in search of a female by emitting a species-specific flashing pattern, and the females sit on the ground and wait until they see an impressive light display. 

Firefly light can ward off predators.

Firefly blood contains a defensive steroid called lucibufagins, which makes them unappetizing to potential hunters. Once predators get a bite, they associate the unpleasant taste with firefly light and avoid attacking the lightning bugs in the future.

Some fireflies are cannibals!

When they become adults, fireflies may eat pollen, nectar or nothing at all! The few species that remain carnivorous through adulthood eat other types of fireflies. 

Now that you know more about the science behind fireflies, you can enjoy them even more this summer! If you plan to catch some fireflies, keep them safe by placing a wet paper towel in the bottom of a glass jar. Pierce holes in the jar’s lid so that the fireflies can breathe. Don’t forget to release them after a day or two!

For all other pest-related problems and inquiries, feel free to drop us a line. Don’t forget to ask about our residential pest control packages!

Scroll to Top