Social behaviors are essential to the lives of many animals. “Complex” social behaviors are interactions among conspecifics take many forms, including repeated associations with particular individuals, interactions that differ across different contexts, or coordinated behaviors among many individuals. In such interactions, the environment that determines the behavior’s success or failure is often defined by the interacting conspecifics themselves. In this talk I will discuss studies of two cooperative bird species that investigate the role of social context in complex cooperative behavior. In the cooperatively displaying lance-tailed manakin (Chiroxiphia lanceolata), male partners form long-term male-male alliances and display together for females. However, all-occurrence video monitoring of display behavior showed that the iconic two-male displays of this species are actually less likely to end with a copulation than displays performed by just one male. So why do males ever display in pairs? We combined male and female perspectives to better understand display and mating choices, and the role of sexual selection in the cooperative interactions of this species. In the brown-headed nuthatch (Sitta pusilla), a more classic cooperative breeder, experimental manipulation of brood sex ratios changed the social landscape of our adult population, resulting in more cooperation when biased adult sex ratios limited mating opportunities for young birds. Both of these studies offer insights from long-term monitoring of wild populations and illustrate the complex web of interactions that shape social behavior.
Emily DuVal is a behavioral ecologist and Professor in the Department of Biological Science at Florida State University. She began studying cooperative behavior in male lance-tailed manakins as a PhD student, and later developed a major line of research understanding the process and outcomes of sexual selection in this species. Her work draws on long-term data from wild populations to understand the selective pressures shaping individual behavior. She earned her PhD from UC Berkeley, under the guidance of Eileen Lacey in the Museum of Vertebrate Zoology, and completed her postdoctoral work with Bart Kempenaers at the Max Planck Institute for Ornithology. The work that she will discuss at ANU is supported in part by an NSF CAREER award.