ORIGINAL PAPER G. S. Pollack Æ V. Givois Æ R. Balakrishnan Air-movement ‘signals’ are not required for female mounting during courtship in the cricket Teleogryllus oceanicus Accepted: 11 June 1998 Abstract Wing movements associated with stridulation by the male during cricket courtship generate air movements that have been proposed to serve as signals to the female. We assessed this putative signaling role by interfering with the presumed communications channel in two ways: (1) by removing the female’s cerci, which are candidate sensory organs for signal reception, and (2) by trimming the male’s forewings and thus manipu- lating the signal itself. We measured the eects of these treatments on the probability and latency with which females mounted courting males. We found that neither treatment aected female mounting behavior. This was true both for old, highly motivated females and for younger females, which are less highly motivated and possibly more selective. We conclude that air movements play little or no role as signals that release female mounting behavior during courtship. Key words Cerci Æ Multimodal Æ Near-field Æ Acoustics Æ Communication Introduction Courtship in field crickets begins when a sexually re- ceptive male comes into contact with a female. The male, upon detecting cuticle-borne pheromones on the body of the female (Loher and Rence 1978; Tregenza and Wedell 1997), initiates a courtship display that includes vibra- tion of the antennae, rocking of the body, stroking of the female and production of courtship song (Alexander 1961; Burk 1983; Loher and Dambach 1989; Adamo and Hoy 1994; Balakrishnan and Pollack 1996). The female, if she is receptive, responds by mounting the male and copulating. The male’s courtship display presents the female with a number of potential signals across several sensory modalities. So far, only acoustic and contact chemo- sensory cues have been shown to play a signaling role (Burk 1983; Libersat et al. 1994; Balakrishnan and Pollack 1996, 1997; Nelson and Nolen 1997). Removal of either of these signals drastically reduces the fre- quency with which females mount courting males (Balakrishnan and Pollack 1996, 1997). The acoustic component of the display, courtship song, is produced by stridulation with the forewings. In addition to gen- erating relatively high-frequency sound, singing pro- duces low-frequency air movements (Ka¨ mper and Dambach 1979, 1985) that reflect the temporal pattern of the opening and closing motions of the wings, and thus of the courtship song. These movements are de- tected by the filiform hairs on the cricket’s cerci and by the interneurons they drive, and it has been suggested that they may serve as additional signal components of the courtship display (Ka¨mper and Dambach 1981; Ka¨mper 1984; Heinzel and Dambach 1987; Heidelbach et al. 1991). However, the mere presence of a stimulus and its detection by sensory systems do not constitute evidence for a signaling function; this can be provided only by behavioral experiments. Here, we test the hy- pothesis that air movements associated with singing af- fect female mounting behavior. Materials and methods Animals Teleogryllus oceanicus were raised in the laboratory at 24–28 °C under a 12 h:12 h photoperiod on a diet of Purina Cat Chow and water. Males and females were separated before the last molt. J Comp Physiol A (1998) 183: 513 – 518 Ó Springer-Verlag 1998 G.S. Pollack (&) Æ V. Givois Æ R. Balakrishnan 1 Department of Biology, McGill University, Montreal, QC, H3A 1B1, Canada e-mail: gpillack@bio1.lan.mcgill.ca, Fax: +1-514-398-5069 Present address: 1 Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India