But the “why” is much more complex.
For one thing, fireflies aren’t even flies, but a kind of beetle. And while it used to be believed that these insects light up just because they’re looking for a mate, a new book reveals that there are a lot more nuances than that.
In fact, each species of 2,000 kinds of fireflies across the world, over 125 of which live in the United States, speaks a slightly different language using their little lamps. Some flash, some glow and others flicker.