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Abstract

In behavioral experiments females of acridid species Chorthippus biguttulus, Ch.parallelus, Ch.dorsatus responded not only to conspecific but to heterospecific songs as well. The response frequency to conspecific songs ranged from 75 to 96%, to the heterospecific songs — from 15 to 38%. The investigation of female responses to artificial songs showed, that in order to recognize the conspecific song Ch.parallelus females use echeme structure (the presence of discrete impulses) and amplitude modulation of the echeme; in Ch.dorsatus ffemales, the presence of two parts in the song as well as subdivision of the first part into the echemes with separate pulses are important for recognition. It is supposed that Chorthippus females do not use one single key characteristic, but employ the whole complex of temporal parameters.

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... Meaningful differences among crosses are confined to the temporal rather than spectral features of songs. This finding is consistent with the more general observation that timing is more important than pitch in determining mate choice among animals with acoustical signals (Pollack, 1979; Doherty, 1985; Schwartz, 1987; Doolan & Young, 1989; Vedenina, 1990; Allan & Simmons, 1994; Ritchie & Gleason, 1995), and it confirms the results of earlier studies on behavioral choice in green lacewings (Wells & Henry, 1992a). Temporal features are also highly correlated with one another (Table 1; correlations not shown), suggesting epistasis and pleiotropy in gene expression. ...
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Chapter
Many acridid species have evolved a means of auditory communication, the chief function of which is to bring sexual partners together, and thereby to ensure the genetic isolation of the species. Both males and females produce the acoustic signals, by rubbing a file with many small teeth on the inside of the hindlegs against prominent veins on the elytra. The songs generated in this way in many cases have a highly developed, complex pattern, as described by Faber (1929, 1953), Jacobs (1953) and Elsner (1974).
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