Fireflies: A Signal For The End Of A Long Summer Day -- By Nick Jiacopello -- Muhlenberg College Class of 2016

Growing up as a kid in South Jersey meant long summer days and endless hours outside. Taking advantage of all daylight hours, my friends and I would hit the beach all day long and then return home, excited to spend the remainder of our day playing wiffle ball in the backyard. As middle school kids with boundless energy, our daily routine only faced one problem- darkness. Each night we would continue our game until it was too dark to go on. After realizing that the team in the lead would often try to end the game early, citing darkness as an excuse, we needed to come up with some kind of signal as to when the game was officially over. This was when my friend, Kevin, decided that we should end the game each night at the sight of the first firefly. From then on, these beautiful, mysterious fireflies, also known as lightning bugs, became an integral part of our summer routine.

Fireflies are beetles and a part of the family Lamypride, as in “lamp.” The name “fireflies” can be misleading since they are not flies at all. They have four wings, a characteristic that clearly distinguishes them from the fly, which has two wings. There are about 2,000 different species of firefly in the world. Here on the east coast, they are nocturnal beetles characterized by their particular use of making light. These insects inhabit a wide variety of moderate to warm environments. They ride out the winter during the larval stage, which is why we would only begin to see these lightning bugs every year when summer rolls around. Found on every continent except Antarctica, fireflies love moisture and tend to live in humid regions where available.

Even though there are large numbers of fireflies in the humid areas of the western United States, the fireflies that actually flash in the US are, for the most part, found east of the state of Kansas. There are lots of fireflies in the west, but they just don’t flash. Therefore, seeing numerous flashing insects when stepping into our backyards during summer nights is not uncommon here in the eastern United States. We would take advantage of their nocturnal, glow in the dark characteristics, and use them to our advantage.

One thing never occurred to me as a young, aggressive boy focused on winning the game at hand, both how and why were these insects lighting up the night? Fireflies have dedicated light organs located under the abdomens. The insects take in oxygen, combine it with a substance called luciferin, and produce light with almost no heat. Each lightning bug species has their own particular blinking pattern, usually an infrequent sequence of flashes. Fireflies use their unique flashing patterns to attract potential mates. They have a variety of ways to communicate with their potential mates in courtships, for example, steady glows versus flashing lights. This selection of mates by simply lighting up is a phenomenal occurrence. As a kid, I would see these insects flying around and think nothing of the amazing flashing patterns displayed by this wonderful creature. But now, when this summer rolls around, it will be exciting to be able to tell everyone exactly why they are acting this way. Fireflies really are an extraordinary type of beetle.

As the summer rolled along, we began to develop a very strong love/hate relationship with these fireflies. Some nights the fireflies signaled victory, while some nights they represented defeat. I have a sharp memory of one particular night in which I was standing on third base, down by one, ready to be driven in as the tying run. All of the sudden, the first lightning bug flashed just in front of the batter, my friend Timmy. He may have been the most competitive in the group and was so furious with the sudden end to such a tight game, that he took the bat and swung at the firefly. As he struck the fly, we watched as the light flashed on and remained on as it flew through the night and landed in the grass near the pitchers mound. The lightning bug lay there, dead, but its light was still on. Once again, as kids focused on more “important” things, we thought nothing of the dead, glowing insect, and cleaned up and headed inside.

This memory of the dead lightning bug seemed like a curious occurrence and something that needed to be examined. It turns out that a firefly’s body will emit a glow for up to fifteen minutes after it has been killed. The different reactants required for the chemical reaction to produce light are mixed together once the firefly has been smashed. The luciferase stored in the firefly’s tail is exposed to other reactants, allowing for the reaction to continue even when the firefly is no longer living. Even though this is another phenomenal characteristic of lightning bugs, recent population decreases represent that we should refrain from smashing them.

The flashing exhibited by fireflies is primarily used for finding partners, but this feature can also have other uses. Some flash to protect their “turf” and to warn predators away. Even larvae light up! The larvae usually live for one full year from mating season to mating season before becoming adults and continuing the cycle. Most fireflies are believed to be primarily carnivorous, but some species are believed to survive only on plant pollen and nectar, or even nothing. Their lifespans are so short, living just long enough to mate and lay eggs, that they may not need to eat during their adult stage.

Warm weather is just around the corner and another reason why we should be so excited for the upcoming spring and summer seasons is to be able to see these unbelievable creatures again. Living in the Lehigh Valley area, don’t be surprised to see these brown, soft-bodied, flashing insects suddenly popping up all over your yard! While it’s fun to watch them light up your garden, as my friends and I did as kids, another fun activity would be to catch the lightning bugs. With the proper environment, you can examine one of these fireflies up close and personal, before setting them back into their appropriate environments. As a huge fan of warm, summer nights spent outside, it will be satisfying to see these creatures light up the yard once again.

Fireflies: A Signal For The End Of A Long Summer Day by Nicholas Jiacopello is licensed under a Creative Commons Attribution 4.0 International License.