Department of Biology, Pomona College, Claremont, CA 91711, USA.
Department of Neuroscience, Pomona College, Claremont, CA 91711, USA.
Proc Biol Sci. 2022 Jul 13;289(1978):20220589. doi: 10.1098/rspb.2022.0589.
The study of song development has focused on temperate zone birds in which typically only males sing. In the bay wren, s, both sexes sing, performing precisely timed, female-initiated duets in which birds alternate sex-specific song phrases. We investigated the development of these sex differences by collecting bay wren eggs and nestlings, and hand-raising them in individual acoustic isolation chambers. Each bird was tutored with either monophonic or stereophonic recordings of bay wren duets or heard no song. As adults, each tutored bird sang repertoires of complete duets, singing both male and female phrases. In addition, some birds sang only the male or female part of some duets to which they were exposed. Mono-tutored birds showed no sex-specificity in these solo songs, whereas stereo-tutored birds only sang solos consistent with their sex. In addition, stereo-tutored birds acquired songs over a longer period than did mono-tutored birds, and stereo-tutored females showed more sex-specificity than did males during early song production. Finally, we observed that tutored and acoustically isolated birds of both sexes invented male-like songs, whereas only males invent songs in the wild. These results reveal the relative roles of environmental versus innate influences in the development of sex-specific song in this species.
歌曲发展的研究主要集中在温带鸟类上,这些鸟类通常只有雄性会唱歌。在海湾鹪鹩中,雌雄两性都会唱歌,它们会进行精确计时的、由雌性发起的二重唱,鸟类会交替唱出特定性别的歌曲短语。我们通过收集海湾鹪鹩的蛋和雏鸟,并在单独的声学隔离室中人工饲养它们,来研究这些性别差异的发展。每只鸟都接受了海湾鹪鹩二重唱的单声道或立体声录音的辅导,或者根本没有听到歌曲。作为成年鸟,每只受过辅导的鸟都会演唱完整的二重唱曲目,演唱雄性和雌性的短语。此外,一些鸟只演唱它们所接触到的某些二重唱的雄性或雌性部分。受过单声道辅导的鸟在这些独唱歌曲中没有表现出性别特异性,而受过立体声辅导的鸟只唱与它们的性别一致的独唱歌曲。此外,受过立体声辅导的鸟比受过单声道辅导的鸟学习歌曲的时间更长,并且在早期唱歌时,受过立体声辅导的雌性比雄性表现出更多的性别特异性。最后,我们观察到受过辅导和声学隔离的雌雄鸟都发明了类似雄性的歌曲,而只有雄性在野外发明歌曲。这些结果揭示了环境与先天因素在该物种中性别特异性歌曲发展中的相对作用。