We all aim for our nights to be “lit” but they aren’t actually lit without the presence of fireflies (or lightning bugs, whatever you call them).  Nothing illuminates a July night quite like the tail regions of these bugs.  Petite lanterns, stars on earth, we like to pretend we respect these bugs more than we do bees or slugs but many of us are still guilty of making “neon paint” from smooshing them (by the way, that isn’t paint, it’s pure insect abuse).  And while we know that these creatures have one divine glow, we are ignorant to the other traits that render these bugs true shining stars (no pun intended) in the entomological world.

What makes the fireflies glow?  While we would probably all hope it’s actually fire, it, unfortunately, is not.  In fact, it is scientifically impossible for these bugs to emit actual fire because if they had an organ that produced enough heat, they would die.  The light, instead, is a chemical reaction of calcium, oxygen, and luciferin.  The enzyme luciferase speeds up the reaction and lessens the amount of energy from ATP necessary to produce this radiance.  In the presence of available oxygen, lightning bugs glow and the glow ends when there is no more free oxygen.  This reaction may sound like biochemical gibberish but it creates a cold light which is one cool phenomenon called bioluminescence.  We touch natural light and we don’t get burned!

These fireflies have an organ dedicated to carrying out this process literally called a “glow organ.”  When we inhumanely smoosh these bugs to examine the luminosity of their blood, it’s the spilling of the blood from this organ.  Feel guilty yet?

If we think about ourselves and our college experiences, the partying only happens after dark.  Fireflies could be a part of any “in” crowd at Penn State because nighttime hours are their hours of fun as well.  While during the day we languish in our classes or sit in our dorms like hermits, the fireflies are hiding away among vegetation.  They don’t glow, they don’t mate, they simply nap in the shade until the sun sets.  Once night falls, males use their glow to communicate and attract females the same way men try to impress us females when we go out at night (let’s not get too detailed).  When fireflies glow, they’re socializing in the same way we socialize with our friends.  However, in the midst of their light-filled conversations, fireflies eat one another.  That’s right, fireflies eat some larger bugs like snails but they are also cannibals.  Imagine having fun at a college party and then, all of a sudden, someone eats you.  That is a firefly’s Friday night.

One repercussion of living as a superstar (whether it’s in Hollywood or among the bugs) is that you have a fair share of professional impersonators.  Glowing click beetles have headlight-like lights attached to them that have mastered the same chemical reaction, but they are only a fraction of the size of firefly light.  Yellow-bordered Flower Buprestids resemble those celebrity imitators that master a star’s look from head to toe but lack the actual substance and talent of that star.  These bugs have wings and markings that could easily pass for a firefly but they cannot produce the same magical cold light that gives fireflies their charm.  Nightfall exposes these impostors.  The soldier beetle is the ugly cousin of these fireflies and its claim to fame is only that it is distantly related to the firefly.  They try and try to imitate their celebrity cousins but unfortunately they live as dull shades of orange and cannot glow.  So many bugs live in the shadows that fireflies cast from their light.

Soldier beetle

Once we recognize all of the fascinating aspects of fireflies, we almost envy these luminous insects that put the “lit” in our summer nights.  Producing an almost divine light through a chemical reaction, we start to wish we had our own “glow organs” and hope evolution will provide us with one.  We also wish we could party every night in the same way fireflies do.  Well we could…but we may not enjoy the repercussions.  We also can admire these bugs as real celebrities with many bugs that wish they could light up the night the way fireflies could.  As we look out our back windows during a summer night, we can now see more than tiny lights that float among the trees.