Acoustic communication in Drosophila melanogaster courtship:: Are pulse- and sine-song frequencies important for courtship success?

During courtship, the male Drosophila melanogaster (Diptera, Drosophilidae) emits two kinds of acoustic signals by means of wing vibrations oriented towards the female: pulse song and sine song. To examine the roles of these two song types, different experimental signals were played back to single pairs of flies (with the males made mute by wing removal). To preserve the natural pattern of sound emission, all the experimental signals were constructed from a representative complete song that included both the pulse and the sine components, recorded during a successful courtship. The first experiment showed that playback of a natural complete song restored to wingless males courtship success comparable to that of normal winged males. In the second experiment, in which we distinguished between the effects of pulse song and sine song, pulse song alone was sufficient to stimulate matings between wingless males and virgin females; sine song had a less stimulating effect. In a third experiment we examined the consequences of modifying the carrier frequency of either signal. This had no particular effect on responses to either pulse or sine song. These results suggest that for both these signals, frequency is not involved in the mating success of D. melanogaster.