Meeting Abstract
Courtship displays are among nature’s most exuberant expressions of biodiversity. But why are they often so complex? One underexplored possibility is that complex male displays function to manage female distractedness. Female attention is limited, and must often be split between mate assessment and other competing tasks, such as foraging and predator avoidance. Thus male displays may evolve to effectively capture and retain female attention. We investigated this hypothesis in the jumping spider Habronattus pyrrithrix, where male courtship displays involve complex movement sequences, bright colors, and vibrational songs. We used live interaction, video playback, and eyetracking studies to better understand how male courtship traits capture, retain, and manipulate female visual attention. First, we find high levels of female distractedness: in live interactions, females only spent ~27% of their time facing displaying males, whereas males faced prospective mates >99% of the time. However, male display elements such as first leg waves and third leg knee movements increase female attentiveness. In playback studies, male courtship waves are more effective than locomotory movements at capturing female attention, and waving movements made males more salient, particularly against complex and/or moving backgrounds. In live interactions, males dynamically modulate their waves: males increase their wave amplitude with increasing distance from females, and when background complexity increases, males move closer to females to increase the salience of their waves. Finally, eyetracker studies indicate that male colors and movements influence where females direct the gaze of their moveable principal eyes. We discuss how female attention may have shaped male display complexity in this and other species.
