Flight Studies on Photic Communication by the Firefly Photinus pyralis

Flash communication by the firefly Photinus pyralis was studied in a stationary, simulated flight apparatus in which an individual of either sex could be "flown" and its flashing behavior and flight orientation recorded in response to photic stimulation. Males made long "flights" showing many of the characteristics of their natural, female-seeking patrol flights. Males oriented their flight vectors towards light emitting diode (LED) flashes that mimicked the responses of females to their patrol flashes. Females flew and responded to male-emulating LED flashes, making a previously unknown early response followed by the typical 2 sec delayed response characteristic of the dialoging perched female, including abdominal aiming of the flash. Pairs consisting of males, in tethered flight, and females, perched, were run in an integrating sphere photometer, permitting the first determinations of flash intensities of both sexes during courtship dialog. The implications of this work on thought about evolution of photic behavior in fireflies are considered.