Posted by Anna Nordén
Jessica mentioned this paper today, and I thought it would be nice to have a modeling paper for the next lab meeting. They show, with two simulation models (intralocus sexual conflict model and environmental sex determination model), how female demographic dominance can influence evolution.
Time: Tuesday August 26th at 10:30 in Argumentet as usual. Since it is my birthday this Saturday, I will bring some extra yummy fika!
When female fecundity is relatively independent of male abundance, while male reproduction is proportional to female abundance, females have a larger effect on population dynamics than males (i.e. female demographic dominance). This population dynamic phenomenon might not appear to influence evolution, because male and female genomes still contribute equally much to the next generation. However, here we examine two evolutionary scenarios to provide a proof of principle that spatial structure can make female demographic dominance matter. Our two simulation models combine dispersal evolution with local adaptation subjected to intralocus sexual conflict and environmentally driven sex ratio biases, respectively. Both models have equilibria where one environment (without being intrinsically poorer) has so few reproductive females that trait evolution becomes disproportionately determined by those environments where females survive better (intralocus sexual conflict model),or where daughters are overproduced (environmental sex determination model). Surprisingly, however, the two facts that selection favours alleles that benefit females, and population growth is improved when female fitness is high,together do not imply that all measures of population performance are improved.The sex-specificity of the source–sink dynamics predicts that populations can evolve to fail to persist in habitats where alleles do poorly when expressed in females.