Female and male zebra finches (Taeniopygia guttata) preferences for normal and modified songs

The zebra finch is an established model species for song preference research in songbirds. In this study, a four-way choice operant paradigm (“carrousel” cage) was used to measure the spontaneous preference of adult birds of both sexes for song stimuli of four different categories: a conspecific song, a duration-stretched version and a vocoded version of the conspecific song, and a heterospecific great tit song. In an earlier operant song discrimination experiment both male and female zebra finches treated duration stretched and vocoded song versions as being different from a normal song. This study examines how the same modified songs are treated in a preference test. The results show that females exhibited a gradient of preferences: they preferred the normal and the duration-stretched song over the vocoded version of the conspecific song, but the vocoded conspecific songs were still preferred over the heterospecific great tit songs. Males preferred duration-stretched conspecific songs over heterospecific songs, but otherwise did not differentiate among the stimuli. In contrast to the discrimination study, the current study also shows a sex difference, with female song preference for normal and duration-stretched conspecific songs being stronger than male preferences. Our results demonstrate that the importance of particular song features as obtained in the context of an operant discrimination task and of a preference test can differ. This illustrates that combining different approaches and testing paradigms may help to better understand the significance of various acoustical parameters of birdsong in relation to its social and ecological functions and their relevance to both sexes.