© 2025. The Trustees of Indiana University
Copyright Complaints
1229 East Seventh Street, Bloomington, Indiana 47405
News, Arts and Culture from WFIU Public Radio and WTIU Public Television
Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations
Some web content from Indiana Public Media is unavailable during our transition to a new web publishing platform. We apologize for the inconvenience.

Firefly Mating Signals

(Art Farmer, Wikimedia Commons)
(Art Farmer, Wikimedia Commons)

Firefly flashes are actually mating signals. Male fireflies cruise the evening air, flashing their lanterns in a pattern characteristic of their species, looking for females of their own kind.

The males of some species flash with a slow glow lasting several seconds; others flicker more than 40 times per second. There are more than 2,000 firefly species worldwide, each with a particular male flash pattern.

The female firefly emerges from her burrow after sunset and waits on the ground. When she detects the flash of a male of her species, the female flashes back in a characteristic female pattern.

Exchanging flashes, male and female find each other and mate. Then the female returns to her burrow, and the male returns to the air. Sometimes, however, the male does not return to the air, because he is eaten by the female.

Female fireflies of some species eat male fireflies of other species. They attract these males by detecting their flash patterns and sending a return flash pattern that imitates a female of the appropriate species. Some of these duplicitous insects have a repertoire of five or more different flash patterns.

So, every time a male firefly sees a responsive female flash in the grass, he faces a life and death dilemma. He could hesitate, and risk losing out to another male in the race to mate, or rush in and risk being eaten alive.

Source

J.E. Lloyd, "Mimicry in the Sexual Signals of Fireflies," Scientific American, July 1981.

Firefly flashes are actually mating signals. Male fireflies cruise the evening air, flashing their lanterns in a pattern characteristic of their species, looking for females of their own kind. 

The males of some species flash with a slow glow lasting several seconds; others flicker more than 40 times per second. There are more than 2,000 firefly species worldwide, each with a particular male flash pattern.

The female firefly emerges from her burrow after sunset and waits on the ground. When she detects the flash of a male of her species, the female flashes back in a characteristic female pattern. 

Exchanging flashes, male and female find each other and mate. Then the female returns to her burrow, and the male returns to the air. Sometimes, however, the male does not return to the air, because he is eaten by the female. 

Female fireflies of some species eat male fireflies of other species. They attract these males by detecting their flash patterns and sending a return flash pattern that imitates a female of the appropriate species. Some of these duplicitous insects have a repertoire of five or more different flash patterns.

So, every time a male firefly sees a responsive female flash in the grass, he faces a life and death dilemma. He could hesitate, and risk losing out to another male in the race to mate, or rush in and risk being eaten alive.

Stay Connected
Walker Rhea has a B.A. in Comparative Literature from Indiana University. In addition to reading and writing about science, he enjoys performing live comedy in Bloomington, IN and studying dead languages.