Auditory pattern recognition and steering in the cricket Teleogryllus oceanicus

Abstract

AbstractMale crickets Teleogryllus oceanicus (Le Guillou) produce a complex species‐specific calling song with phrases combining groups of single pulses (chirps) and groups of double‐pulses (trills) to attract females, which fly or walk towards singing males. In open‐loop trackball experiments, phonotactic steering responses to normal calling song phrases consisting of chirps and trills are strongest, suggesting that both components are necessary for maximal attractiveness. Sequences of just chirps or trills are less effective in eliciting phonotactic walking and steering. Split‐song paradigms are used to analyze the steering behaviour underlying orientation in more detail. The females' phonotactic steering reflects the alternating acoustic pattern of the split‐song paradigm. Analysis with high temporal resolution demonstrate, that even when the calling song is presented only from one side, the steering velocity and lateral deviation towards the song is modulated by steering events to single‐sound pulses. Therefore, pattern recognition, which integrates the structure of the song, appears not to be directly involved in the rapid steering response. This organization of phonotactic behaviour with a parallel processing of pattern recognition and steering is similar to other cricket species and may allow T. oceanicus females to steer transiently towards distorted song patterns as they occur in natural habitats.