Sound radiation and wing mechanics in stridulating field crickets (Orthoptera: Gryllidae)

Abstract

SUMMARYMale field crickets emit pure-tone mating calls by rubbing their wings together. Acoustic radiation is produced by rapid oscillations of the wings, as the right wing (RW), bearing a file, is swept across the plectrum borne on the left wing (LW). Earlier work found the natural resonant frequency (f o ) of individual wings to be different, but there is no consensus on the origin of these differences. Previous studies suggested that the frequency along the song pulse is controlled independently by each wing. It has also been argued that the stridulatory file has a variable f o and that the frequency modulation observed in most species is associated with this variability. To test these two hypotheses, a method was developed for the non-contact measurement of wing vibrations during singing in actively stridulating Gryllus bimaculatus. Using focal microinjection of the neuroactivator eserine into the cricket's brain to elicit stridulation and micro-scanning laser Doppler vibrometry, we monitored wing vibration in actively singing insects. The results show significantly lower f o in LWs compared with RWs, with the LW f o being identical to the sound carrier frequency (N44). But during stridulation, the two wings resonate at one identical frequency, the song carrier frequency, with the LW dominating in amplitude response. These measurements also demonstrate that the stridulatory file is a constant resonator, as no variation was observed in f o along the file during sound radiation. Our findings show that, as they engage in stridulation, cricket wings work as coupled oscillators that together control the mechanical oscillations generating the remarkably pure species-specific song.Supplementary material available online at

Wing mechanics, vibrational and acoustic communication in a new bush-cricket species of the genus Copiphora (Orthoptera: Tettigoniidae) from Colombia

“…For the experiments, the insect was mounted on a horizontal brass platform following the procedure described by Montealegre-Z et al (2011a).…”

Systematics and Acoustics of North AmericanAnaxipha(Gryllidae: Trigonidiinae)

“…(8) during the main portion of the pulse, impacts of the scraper on the file teeth are synchronous with the fundamental oscillations of the song and hence with the principal vibrating areas of the wings (kreidl & regen 1905according to dumortier 1963, Pierce 1948, Walker 1962b, dumortier 1963, nocke 1971, elliott & koch 1985, Montealegre-Z et al 2011.…”

Changing resonator geometry to boost sound power decouples size and song frequency in a small insect

“…During stridulation, the wings of crickets, when set in motion by the action of the stridulatory apparatus, vibrate and produce pressure variations in the surrounding medium effectively producing sound (3). Sound radiation using wings has been studied in many groups in the singing Orthopteran insects: bush crickets (30), crickets (27,28,32) and tree crickets (23). In most crickets, only part of the wing (the harp or the mirrors) moves significantly and radiates sound at the song CF (27,30,32).…”

“…Sound radiation using wings has been studied in many groups in the singing Orthopteran insects: bush crickets (30), crickets (27,28,32) and tree crickets (23). In most crickets, only part of the wing (the harp or the mirrors) moves significantly and radiates sound at the song CF (27,30,32). Unusually, in O. henryi the entire wing (the harp, and the three distal wing mirrors) shows significant vibrational behavior (Fig.…”

“…Little is known, however, about the relationship between temperature, the stridulatory mechanism, and wing resonances in Oecathines (23,26). Even less is known about the evolutionary reasons for their remarkable wings and the consequences of having sound radiators that are so different from those of the previously studied field crickets (27,28) and katydids (29,30).…”