Fireflies Sync Their Flashes

Swarms of synchronous fireflies are rather like melting ice, or at least that’s how Raphael Sarfati, a physicist, sees it. Ice remains solid until it warms to a certain temperature and becomes a liquid. Likewise, a loose swarm fireflies will flash the lanterns in their abdomens randomly. But when the swarm reaches a certain density, the fireflies begin to blink in unison.

“Above that threshold, it is almost perfect synchronization,” with rhythmic, coordinated waves of light, said Sarfati, a postdoctoral associate at the University of Colorado, Boulder.

The spontaneous synchronization of certain species of fireflies, such as Photinus carolinus in the Great Smoky Mountains in North Carolina and Tennessee, has long baffled humans who observed the peculiar mating ritual, in which blinking males strive to attract the attention of ground-level females. 

Early-20th-century scientists dismissed the phenomenon as accidental or blamed it on puffs of wind or the twitching eyelids of the people who made these reports, according to one 1935 review in Science.

In the past 50 years, scientists collected anecdotal observations of these unified flashes but not enough empirical data to truly study firefly synchronization’s mechanisms.

Now, Sarfati and Orit Peleg, a physicist and assistant professor also at the University of Colorado, have filmed the mating hordes of P. carolinus and mapped their flashing patterns in three-dimensional space. 

Their research, published Wednesday in the journal Science Advances, adds to evidence that the insects sync their flashes, and suggests what may drive that coordination. TO READ THE ENTIRE ARTICLE, CLICK HERE...