The courtship song of Drosophila has been extensively used as a model system for studies of sexual selection and species recognition. Traditionally, the courtship song has been recorded from males placed individually with a female. However, under natural conditions females are exposed to multiple courting males, and the effect of their joint signal on mate recognition by the female is not yet understood. Here, we recorded the courtship behavior of D. melanogaster males singing either individually to a female (1:1) or in the presence of an additional male (2:1). We compared the structure of the male song in the two experimental designs. Our results show that when two males courted a female their songs could overlap each other. Males produced a significantly different signal in the presence of competition; the duration of each song component was significantly shorter and the rate of singing was markedly lower. The present study demonstrates that male competition can dramatically alter the acoustic signal detected by the female.
Bibliographical noteFunding Information:
We thank Jeff Hall and Bambos Kyriacou for critical comments on the manuscript. We thank Jeremy Richardson for help in building recording chambers and audio amplifier. This work was supported by a Whitehall Foundation grant to D.F.E. and by a University of Iowa Biosciences Initiative postdoctoral fellowship awarded to E.T.
- Courtship song
- Drosophila melanogaster
- Male competition
- Markov processes
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Insect Science