Behavioural responses to video and live presentations of females reveal a dissociation between performance and motivational aspects of birdsong

Understanding the regulation of social behavioural expression requires insight into motivational and performance aspects of social behaviours. While a number of studies have independently investigated motivational or performance aspects of social behaviours, few have examined how these aspects relate to each other. By comparing behavioural variation in response to live or video presentations of conspecific females, we analysed how variation in the motivation to produce courtship song covaries with variation in performance aspects of courtship song in male zebra finches (Taeniopygia guttata). Consistent with previous reports, we observed that male zebra finches were less motivated to produce courtship songs to videos of females than to live presentations of females. However, we found that acoustic features that reflect song performance were indistinguishable between songs produced to videos of females and songs produced to live presentations of females. For example, songs directed at video presentations of females were just as fast and stereotyped as songs directed at live females. These experimental manipulations and correlational analyses reveal a dissociation between motivational and performance aspects of birdsong and suggest a refinement of neural models of song production and control. In addition, they support the efficacy of videos to study both motivational and performance aspects of social behaviours.