The role of demography in the evolution of breeding strategies [article]

Anna Mathilde Freya Harts, University, The Australian National, University, The Australian National
2016
The five chapters of this thesis all focus on the role of demography in the evolution of breeding strategies. In the first chapter we explore the role of the adult sex ratio (ASR) in the evolution of mate-guarding duration. Our two models predict male guarding duration to increase with decreasing female availability and increasing number of male competitors. However, with a male biased ASR there are several factors, such as guarding inefficiency and incomplete last male sperm precedence, that
more » ... precedence, that prevent the mating system from switching to male monogamy. The second chapter adresses a situation where females have a larger effect on population dynamics than males (i.e. female demographic dominance). This occurs when female fecundity is relatively independent of male abundance, while male reproduction is proportional to female abundance. Our two simulation models combine dispersal evolution with local adaption subjected to intralocus conflict and environmentally driven sex ratio biases, respectively. Our proof of principle demonstrates that trait evolution is dominated by environments with a higher abundance of females, although this does not imply that all measures of population performance are improved. In the third chapter we focus on the role of owning a breeding territory for different rates of natal and breeding dispersal. For this we investigate the interplay of the asset-protection principle and the multiplier effect. Our simulation model is set in habitats of spatially varying quality and individuals express dispersal rates based on their life history stage, sex and quality of their habitat. Breeders can evolve high dispersal rates but only if better opportunities are readily available. Non-breeders evolve dispersal mostly in response to competition. For the fourth chapter we stay with the importance of breeding territories, however we shift our focus to its role as a selective force for early arrival in migratory species. We investigate the role of predation upon arrival at breeding grounds as a selective forc [...]
doi:10.25911/5d78d60cef0ec fatcat:ycm5jfvtlbbrjcpbfpf7np77zu