Fireflies are the romantics of the insect world. In the summer months, they emerge from the ground with love on the brain. They only live for two to three weeks once they’ve become full adults and in that time they don’t even eat. They’re too busy flirting.
Fireflies — or lightning bugs, depending on where you grew up — are one of the only insects with elaborate courtship dialogues, said Avalon Owens, a research fellow at Harvard.
Male fireflies fly around and a part of their abdomen called a lantern will “light up in a little advertisement, like a billboard,” per Owens. Then females sitting on the ground look up at the display and flash back to the males they decide they like.
“This is the precursor to meetings,” Owens said. “So they’re not going to mate unless they’ve had this little dance where they’ve exchanged these light signals.”
Different firefly species have performed variations of that light dance for millions of years, lit only by the moon.
Now artificial lights are killing their mood.
Humans have been acting like buzzkills, turning on the overhead lights at the fireflies’ summer party with street lamps, floodlights and LEDs.
In the firefly world, it’s the females who are particularly turned off by artificial light.
Owens led studies in experimental conditions and field conditions and found that male fireflies often keep flashing under street lamps and other kinds of overhead light, while nocturnal female fireflies essentially shut down and stop responding.
“Probably because they just can’t see the males very well,” Owens explained. “Typically male fireflies are looking down. Female fireflies are looking up at street lights and other light sources.” [Continue reading…]