Xiang-Yi Li, University of Neuchâtel: Theory models inspired by the life history and ecology of birds

Theory models have been playing an important role in aiding our understanding of the complex ecological and evolutionary dynamics in populations of birds, such as male competition, female mate choice, extra-pair paternity, bi-parental care, and dispersal. They can help explain the observed phenomena, and/or make predictions to be tested in future empirical investigations. Previous theory models, however, often ignore a number of biological factors that can substantially affect the interactions in bird populations, particularly those between males and females. In this talk, I will use a few models my collaborators and I recently developed to illustrate that, the explanation and prediction power of theory models can be enhanced by considering relevant biotic factors. For example, by considering resource competition between sexes, we could better explain the pattern of sex-biased dispersal, and the rarity of large sexual dimorphism in resource use, like the case in the now extinct Huia bird. In addition, by considering the genotype-by-environment interactions and intralocus sexual conflict, we could identify conditions under which females evolve to prefer low-quality males over high-quality ones. In an on-going study in collaboration with Wolfgang Goymann, we found conditions where a highly cooperative outcome (with high levels of female fidelity and male help stably coexist even at the absence of mate guarding) can be produced from totally selfish optimizations of individual fitness by males and females, when intralocus sexual conflict is taking into consideration.