Relative Importance of Song Parameters During Flight Phonotaxis and Courtship in the Bladder Cicada Cystosoma Saundersii

Abstract

ABSTRACT Parameters of the calling song that were necessary to evoke phonotaxis in female bladder cicadas (Cystosoma saundersii) were determined for both long-range and short-range communication between the sexes. Females flew to loudspeakers that were broadcasting model calling songs that resembled the natural calling song of the males. They also initiated courtship in response to the model calling songs. When flying females were offered a choice between a model resembling the natural song in all parameters (the control model) and a model in which one of the temporal parameters had been changed (the experimental model), they were attracted equally to the control and experimental models. When the carrier frequency of the experimental model was changed, the females were attracted exclusively to the control model. When the same model calling songs were presented to tethered, flying females in the laboratory, they turned only towards models with a carrier frequency close to that found in the natural song. Changing the temporal parameters of the model did not affect either the turning preferences of the females or their reaction times. When the same series of control and experimental models were played, one at a time, to caged females in the laboratory, courtship responses were elicited only by models with temporal parameters similar to those of the natural song. In contrast, a wide range of carrier frequencies was found to elicit courtship, provided that the temporal parameters were similar to those of the control. It is concluded that, in C. saundersii, identification of conspecific males by females is a two-stage process, with the carrier frequency of the male calling song being more important in long-range communication (flight) and the temporal parameters of the calling song being more important in short-range communication (courtship).