S01-3 Neuro-ecology of song complexity in Bengalese finches

The Bengalese finch, Lonchura striata var. domestica, a strain derived from the wild white-rumped munia, Lonchura striata, has been under domestication in Japan for 240 years. We compared song syntax of these two strains and found that the domesticated strain developed highly complex, conspicuous songs, whereas the wild strain sang very stereotyped songs. To identify a possible neural substrate responsible for this difference in song behavior, we performed a lesion study. In Bengalese finches, lesions of the NIf, a higher order song control nucleus, resulted in simplification of complex song syntax. We then compared the levels of serum estradiol in female birds that were stimulated with complex or simple song. Estradiol levels were significantly higher in the females stimulated by complex songs. Based on these data, we hypothesize that a mutation in the song control nucleus occurred in the domestic strain that enabled the development of complex song syntax, and that this mutation became fixed in the domestic population through sexual selection.