Temperature coupling in cricket acoustic communication

Abstract

Acoustic communication in Gryllus firmus is temperature-coupled: temperature induces parallel changes in male calling song temporal pattern, and in female preference for song. Temperature effects on song production and recognition networks were localized by selectively warming head or thorax or both head and thorax of intact crickets, then eliciting aggression song production (males) or phonotaxis to synthetic calling song (females). Because male song is produced by a thoracic central pattern generator (CPG), and because head ganglia are necessary for female song recognition, measurements of female phonotaxis under such conditions may be used to test the following competing hypotheses about organization of the song recognition network: 1. A set of neurons homologous to the male song CPG exist in the female, and are used as a template that determines preferred values of song temporal parameters for song pattern recognition (the common neural elements hypothesis), and 2. temporal pattern preference is determined entirely within the head ganglia. Neither selective warming of the head nor of the thorax was effective in changing female song preference, but simultaneous warming of head and thorax shifted preference toward a faster song in most preparations, as did warming the whole animal by raising ambient temperature. These results suggest that phonotactic preference for song temporal pattern is plurisegmentally determined in field crickets. Selective warming experiments during aggression song production in males revealed that syllable period is influenced but not completely determined by thoracic temperature; head temperature is irrelevant. The song CPG appears to receive some rate-setting information from outside the thoracic central nervous system.

How male sound pressure level influences phonotaxis in virgin female Jamaican field crickets (Gryllus assimilis)

“…Similar to our study, Stout, Atkins & Zacharias (1991) investigated female Acheta domesticus response to differing signal intensities. Conversely, Walikonis et al (1991) investigated female A. domesitcus response to differing syllable periods while Pires & Hoy (1992) investigated female G. firmus response to natural calls recorded songs at different temperatures. Given sound pressure level, syllable period, and temperature are important predictors of mating preference, our joint findings suggest that open arena and spherical treadmill methods may be used interchangeably to quantify phonotaxis to acoustic signals.…”

Sexual selection and speciation in field crickets

“…First, we tested female ''preferences'' as the stimulus level that elicits the greatest positive response. Female preferences were standardized to 25°C by using a linear female temperature response (e.g., a female that preferred the 23°C song when tested at 24°C was assigned a 24°C preference at 25°C); linear temperature responses are appropriate because it is known that both male songs and female preferences are temperature coupled and show identical linear responses (59)(60)(61). Second, we tested female ''recognition'' of heterospecific stimuli in terms of whether females showed average positive phonotaxis when presented with heterospecific song.…”

Chill out: cooling promotes aggressive behavior in the ant Formica xerophila

“…For example, cooling can affect various foraging behaviors in bees (Robinson and Visscher, 1984;Wilson et al, 2006). Furthermore, temperature variation has been shown to affect aggressive behavior in crickets (Pires, 1992). It is possible that this cooling/warming process affects behavior in other insects as well.…”