Fireflies and Femmes Fatales
I'm sitting in my screened porch typing this blog entry. It's dusk and the fireflies are twinkling on my lawn. It has been an excellent year for fireflies here in Illinois. Right in my front yard, there have been dozens flashing every night for weeks now.
A lot of the luminescent acrobatics are about sex. The males fly about and flash in a complex pattern of blinks. The females sit in the grass or on bushes. When one sees flashes in her species' pattern, she waits a precise amount of time and answers with a single flash. The male then descends to mate with her. Usually.
In some cases, female fireflies give the response signal for other species. When a male arrives, instead of getting a little action he becomes a meal. These dangerously deceptive females are known as femme fatale fireflies.
"Don't give me any of that 'hey, Baby' crap. Urrp."
For a long time, I thought that firefly luminescence was all about sex- or occasionally deception. This spring, while preparing my firefly talk, I discovered a new wrinkle. Fireflies are toxic. They contain compounds similar to bufotoxins- the poisons in toad skin. The luminescence may also be a warning or aposematic signal. "Don't eat me- you'll barf. " Some investigators believe that femme fatale fireflies