Physical and temporal scaling considerations in a robot model of cricket calling song preference

Behavioural experiments with crickets show that female crickets respond to male calling songs with syllable rates within a certain band-width only. We hare made a robot model in which we implement a simple neural controller that is less complex than the controllers traditionally hypothesised for cricket phonotaxis and syllable rate preference. The simple controller, which had been successfully used with a slowed and simplified signal, is here demonstrated to function, using songs with identical parameters to those found in real male cricket song, using an analog electronic model of the peripheral auditory morphology of the female cricket as the sensor. We put the robot under the same experimental conditions as the female crickets, and it responds with phonotaxis to calling songs of real male Gryllus bimaculatus. Further, the robot only responds to songs with syllable rates within a band-width similar to the band-width found for crickets. By making polar plots of the heading direction of the robot, we obtain behavioural data that can be used in statistical analyses. These analyses show that there are statistical significant differences between the behavioural responses to calling songs with syllable rates within the band-width and calling songs with syllable rates outside the band-width. This gives the verification that the simple neural control mechanism (together with morphological auditory matched filtering) can account for the syllable rate preference found in female crickets. With our robot system, we can now systematically explore the mechanisms controlling recognition and choice behaviour in the female cricket by experimental replication.