Final Report Summary - POLYINBREED (Coevolutionary Quantitative Genetics of Polyandry and Inbreeding in the Wild: New Theory and Test)
One fundamental aim in biology is to understand the evolutionary causes and consequences of key reproductive strategies that determine how genes are propagated across generations. However, until PolyInbreed, key questions regarding the evolutionary causes and consequences of two major interacting reproductive strategies - polyandry (i.e. female mating with multiple males within a single reproductive episode) and inbreeding (i.e. reproduction among relatives) - had not been satisfactorily addressed either theoretically or empirically. Field empirical studies had typically relied on assessing phenotypic relationships between reproductive phenotypes and fitness rather than directly estimating underlying genetic covariances that shape evolution. Existing theory had not considered dynamic genetic covariances arising in systems with biparental reproduction, or considered key evolutionary processes arising in small populations with interacting relatives. Accordingly, PolyInbreed successfully achieved its overall aims of providing major theoretical and conceptual advances in understanding the dynamics of such mating systems, and in advancing and applying cutting-edge evolutionary quantitative genetic approaches to provide the first tests of key hypotheses in nature.
Theoretically, we used genetically-explicit individual-based simulations, and mathematical models, to identify conditions that foster and constrain the evolution of polyandry, and of active strategies of inbreeding avoidance or preference in biparental systems. These models showed how constraints on male reproductive strategy can drive evolution of female multiple mating (i.e. polyandry), and identified conditions that could foster or impede evolution of active strategies of inbreeding avoidance or inbreeding preference and associated parental investment. Empirically, we used an outstanding dataset from free-living song sparrows to provide the first estimates of key genetic and phenotypic covariances involving extra-pair reproduction (which results from polyandry), inbreeding and fitness, and to quantify the consequences of the expression of these traits for population relatedness structure.
The PolyInbreed work, and resulting conceptual and methodological advances, is presented in 26 papers published to date, including three reviews and a methodological ‘how to’ paper and associated software package to facilitate quantitative genetic analyses. It was also presented in high profile plenary lectures, most notably at the European Society for Evolutionary Biology congress in 2015. The work is already fostering further new theoretical and empirical projects in evolutionary ecology. PolyInbreed was also highly successful in allowing me to build the mixed theoretical-empirical research team that I required to answer the focal questions, and thereby establish my research career.
Theoretically, we used genetically-explicit individual-based simulations, and mathematical models, to identify conditions that foster and constrain the evolution of polyandry, and of active strategies of inbreeding avoidance or preference in biparental systems. These models showed how constraints on male reproductive strategy can drive evolution of female multiple mating (i.e. polyandry), and identified conditions that could foster or impede evolution of active strategies of inbreeding avoidance or inbreeding preference and associated parental investment. Empirically, we used an outstanding dataset from free-living song sparrows to provide the first estimates of key genetic and phenotypic covariances involving extra-pair reproduction (which results from polyandry), inbreeding and fitness, and to quantify the consequences of the expression of these traits for population relatedness structure.
The PolyInbreed work, and resulting conceptual and methodological advances, is presented in 26 papers published to date, including three reviews and a methodological ‘how to’ paper and associated software package to facilitate quantitative genetic analyses. It was also presented in high profile plenary lectures, most notably at the European Society for Evolutionary Biology congress in 2015. The work is already fostering further new theoretical and empirical projects in evolutionary ecology. PolyInbreed was also highly successful in allowing me to build the mixed theoretical-empirical research team that I required to answer the focal questions, and thereby establish my research career.