ABDOMINAL VENTILATORY PATTERN IN CRICKETS DEPENDS ON THE STRIDULATORYMOTOR PATTERN

Ventilatory motor patterns were recorded from abdominal muscles in cri ckets, Gryllus campestris L. and Teleogryllus commodus (Walker), at re st and during three types of stridulatory motor activity; calling, cou rtship and aggressive song. Increases in ventilatory period were almos t exclusively due to an increase of the pause between expiratory burst s, whereas abdominal ventilatory bursts remained constant at 200 ms. V entilatory patterns depended on the stridulatory motor pattern and ind icated that the same basic respiratory oscillator exists in both crick et species. In G.campestris there was a strict 1:1 coupling between ch irps and ventilatory bursts. In T.commodus such a relationship was als o observed for the chirp part of the songs, but less strictly for the trill part of the calling song and not for the courtship song. In both species the onset of the ventilatory burst was within +/- 100 ms of a stridulatory chirp. Ventilatory burst lasted longer the earlier they began before a stridulatory chirp. This suggests strongly that the str idulatory motor pattern terminates the expiratory burst, and thus infl uences the ventilatory motor pattern.