Evolutionary demography of structured two-sex populations and sex ratios
MetadataShow full item record
Males and females may differ in stage-specific survival, maturation, fertility, or mating availability. These demographic differences, in turn, affect population growth rates, equilibrium structure, and evolutionary trajectories. Models considering only a single sex cannot capture these effects, motivating the use of demographic two-sex models for sexually reproducing populations. I developed a new two-sex modeling framework that incorporates population structure and multiple life cycle processes through transition rate matrices. These models can be applied to a variety of life histories to address both ecological and evolutionary questions. Here, I apply the model to the effects of sex-biased harvest on populations with various mating systems. Demographic considerations also affect evolutionary projections. I derived matrix calculus expressions for key evolutionary quantities in my two-sex models, including the invasion fitness, selection gradient, and second derivatives of growth rates (which have many applications, including the classification of evolutionary singular strategies). I used these quantities to analyze the evolution of the primary sex ratio, under various sex- and stage-specific offspring costs and maternal conditions. Demographic two-sex models lend insight into complex, and sometimes counterintuitive, results that are not captured by models lacking population structure. These findings highlight the importance of demographic structure in ecology and evolution.
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 2015
Showing items related by title, author, creator and subject.
Saal, Alberto E. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1999-09)Geochemical studies are fundamental for understanding how the dynamic Earth works and evolves. These studies place constraints on the composition, formation, age, distribution, evolution and scales of geochemically ...
Fox-Kemper, Baylor (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2003-06)Inertial terms dominate the single-gyre ocean model and prevent western-intensification when the viscosity is small. This occurs long before the oceanically-appropriate parameter range. It is demonstrated here that the ...
Brownawell, Bruce J. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1986-04)Polychlorinated biphenyls (PCBs) were used as model hydrophobic organic compounds (HOC) to study physical~chemical processes which affect the speciation and fate of HOC in coastal environments. The focus of this study ...