The context of communication: Social influences on development in cowbirds

I have studied how group living can influence the development of male courtship song and female song preferences in a social songbird, the brown-headed cowbird Molothrus. I allowed juvenile males to develop in social groups differing in the age-class composition of individuals present. In some groups, juveniles had the opportunity to interact with adult males, in other groups they could only interact with peers. Song development, song use, and song quality were all influenced by the social group with whom juvenile males experienced during their early life. In a second series of experiments, I investigated whether female preferences for male song could be modified by social experience. Two decades of past work in sound attenuation chambers had consistently failed to find malleability in female preferences. By housing females socially however, I was able to modify preferences for song variants using a playback tutoring paradigm. Taken together, these two research preparations reveal the high degree of context-dependence on the development of communicative signals. They highlight the need to consider social context in studies of physiology, behaviour, and evolution.