Reading the Language of Firefly Flashes
by AMNH staff
Flashing flirted its way up the firefly family tree.These beetles’ evolutionary history shows a strange metamorphosis unfolding. Firefly eyes grow bigger, more bug-like, as the insects’ light organs enlarge. Their antennae, used like a nose to follow pheromones, shrink into stubs. The more important bioluminescent courtship signaling became throughout their history, the more the trappings of invisible communication faded out.
When Marc Branham, a professor of entomology at the University of Florida, began researching fireflies, he assumed such a beloved animal would be a textbook case in entomology. He was shocked to learn how little scientists knew about the common insect.
(This table shows the diverse timing and repetition of flash dialogues from five firefly species. Shaded boxes represent repeating sequences. Blank boxes indicate “optional” flashes that reflect variation among individuals. Source: Lloyd, James E. (1966). Studies on the Flash Communication System in Photinus Fireflies. Table © AMNH/Hinterland)
What researchers did know was that each species of bioluminescent adult firefly has its own flash fingerprint. Males fly through the air and search for females with a species-specific light display. Some flash only once. Some emit “flash trains” of up to nine carefully timed pulses. Others fly in specific aerial patterns, briefly dipping before sharply ascending and forming a “J” of light. A few even shake their abdomens from side to side and appear to be twinkling. “So if you’re looking over a field,” says Branham, “You can pretty accurately tell how many species are in that area.”…
(read more: AMNH) (photo: Quit007)