Meeting Abstract
28.3 Saturday, Jan. 4 14:00 Experimentally testing potential benefits of cooperative display in passerine bird JONES, M.A.; Florida State University majones@bio.fsu.edu
Much of the research of understanding cooperative behaviors has focused on why helpers assist. There has been little attention to why the recipient of the help participates; the benefit is often assumed. Yet it is equally important to understand the costs and benefits of cooperation for the recipient. Within a single population of Corapipo altera (White-ruffed Manakin) some males participate in coordinated display with other males, while other males display singly. The variation in cooperative display participation within a single population offers an opportunity to investigate the costs and benefits of cooperation for dominant individuals. Here I present three experiments that test potential benefits of cooperation to dominant individuals. 1) Cooperative dominant individuals may benefit by more effective detection of conspecific intruders. Non-cooperating males near a dominant male’s display area may sneak copulations decreasing the dominant male’s reproductive success. We tested this hypothesis using playback to simulate a conspecific male intrusion. 2) Dominant individuals may increase their chances of survival with the presence of other males. Longer survival may result from increased vigilance for predators or division of mortality risk during a predation attempt. I tested this possibility by presenting a predator model near each display site. 3) Cooperative display may provide direct benefits to the dominant male by increasing his reproductive success. One mechanism through which this could occur is faster initiation of courtship by the males. Shortening the onset of courtship increases the reproductive success of the dominant male. We tested this hypothesis by presenting a live, caged female at display sites. Overall, we found that some dominant males benefit from cooperative display, but that they also have increased costs.
