How Fireflies Glow and What Signals They’re Sending
via Phys.org
You might not really be sure you saw what you think you saw when the first one shows up. But you stare in the direction of the flicker of light and there it is again—the first firefly of the evening. If you are in good firefly habitat, soon there are dozens, or even hundreds, of the insects flying about, flashing their mysterious signals.
Fireflies—alternatively known as lightning bugs in much of the United States—are neither flies nor bugs. They’re soft-winged beetles, related to click beetles and others. The most dramatic aspect of their biology is that they can produce light; this ability in a living organism, called bioluminescence, is relatively rare.