Special Seminar - Brian Lerch: Allee effects, social dynamics, cooperation, and mate choice

Abstract:

First, it has been established that group dynamics and, in particular, coevolution with group size can favor the evolution of cooperation. However, such work makes assumptions that are not realistic for some well-known cooperative breeders such as African wild dogs (Lycaon pictus) and meerkats (Suricata suricatta). Most notably, it remains unclear how group size and cooperation coevolve in stable groups with complete reproductive skew. Here, I develop and analyze a model of a social group with robust ecology based on social carnivorans. I find that, under a range of conditions, increased cooperation will evolve. Importantly, this result provides a potential mechanism for the evolution of cooperation in groups with only one reproductive individual without invoking kin selection or group selection arguments. Second, territorial breeders are widespread and occur across taxa. Often, these species are characterized by males establishing territories to which they attract females. There exists theory for how territory establishment occurs, but such work ignores the subsequent choice females make in deciding with whom to mate. Here, I develop and analyze a spatially explicit model of male territory establishment and female mate choice. I find that sexually antagonistic selection (i.e., a negative correlation between male and female fitness) occurs in a suite of parameter combinations and model assumptions. Importantly, I find that this is the result of an edge effect on the nite landscape.