COPELAND, J.; MOISEFF, A.; Georgia Southern University; University of Connecticut: Synchronic flashing in a North American firefly

Synchronic fireflies produce flashes with remarkable temporal precision. This phenomenon was first studied in Southeast Asian fireflies by Buck, Buck, Case, and Hanson. Recently, we described synchronic behavior in the North American firefly Photuris frontalis. Ph. frontalis is the only known species of the genus Photuris to synchronize as a regular part of its flash behavior. The robustness of its synchronic behavior and our easy accessibility to stable populations have enabled us to investigate the nature of synchrony in these fireflies. We used photometry and synthesized flashes to study the precision involved in the initiation of synchrony in caged fireflies. When a visual barrier was removed between two fireflies, one firefly continued to flash. The second firefly showed a temporary initial inhibition. The initial inhibition lasted from 3.0 – 24.1 sec after which the second firefly resumed its flashing. The second firefly’s flashes were immediately synchronous with the first firefly’s flashes at a phase of 0.9s – 1.2, i.e., near perfect synchrony. Similar results were obtained when individual fireflies were tested using Hanson’s flash entrainment paradigm. Rhythmic flashes of an LED were artificially produced and presented to an isolated firefly. When these rhythmic entrainment pulses were presented, the firefly stopped flashing. After several seconds, the began to flash again. The first flash of the firefly was phase locked to an entrainment flash at a small delay. The synchronic timing of the firefly, as well as the precision of its spontaneous flashing, make the North American firefly Ph. frontalis useful in studies of biological timing. The behavioral function of flash precision is not yet known. Sponsored by Georgia Southern University and University of Connecticut.