Variability in preference for conspecific songs with syntactical complexity in female Bengalese Finches: towards an understanding of song evolution

摘要

Male Bengalese Finches Lonchura striata var. domestica sing syntactically complex songs. A previous study suggested that complex songs elicit more reproductive behavior in female Bengalese Finches than do simple songs. Since the study measured passive reactions to stimulus songs, it is not clear if female birds actively choose complex songs. Here we conducted an active choice experiment using female Bengalese Finches in which selecting a particular perch resulted in the playback of a simple or a complex song. Four out of the eight birds chose complex songs, one chose the simple song, and the remaining three chose both songs randomly. These results suggest that the song preferences of female Bengalese Finches vary individually. A simple population dynamics model confirmed that such a tendency in female preference could lead to the evolution of complex songs in male Bengalese Finches.