The role of sexual selection and population subdivision in pop persistence in a changing world

Principal researcher: Francisco García González.

Period: 2020-2024

Determining whether sexual selection accelerates or hampers adaptation in novel environments is a central question in evolutionary biology. Resolving this question has important implications for understanding the potential of populations to persist in the face of rapid environmental change. Sexual selection can theoretically facilitate or hinder adaptation to new environments, depending on whether it works as a filter reducing mutational loads, or on whether the negative population-level consequences of sexual conflict are reduced under environmental stress. Few empirical studies have formally tested the alignment or misalignment of sexual and natural selection, and strikingly, no study has explored whether a key ecological and demographical factor such as population spatial structure moderates the effect of sexual selection on adaptation. This project will innovatively investigate the interactive influences of sexual selection (including sexual conflict) and population subdivision on the individuals' and the populations' ability to withstand environmental change. The project will take advantage of the power of experimental evolution to address these questions. It will use selection lines of a pest beetle that have been subject to variation in selection arising from reproductive competition and population spatial structure for over eighty generations, and it will measure a wide array of relevant phenotypic and life-history traits (including lifetime reproductive success, behavioural plasticity, resistance to environmental stressors) and population traits (including population viability and realized extinction events) in response to exposure to environmental disturbances. Sex-specificity underlying evolutionary responses, and the genetic basis providing the potential for evolution will be inspected. In addition, this project will also investigate (both within and outside a context of variation in selection histories), whether non-genetic inheritance via transgenerational effects, and in particularly father-offspring transmission of altered environments, play a role in adaptation to changing environments. Results will inform on whether sexual selection, population spatial structure, their interaction, and transgenerational plasticity, accelerate adaptation, or on the contrary, hinder components of viability selection. Alterations of population spatial structure (e.g., through habitat fragmentation) represent key conservation threats and this work will provide useful empirical data on how these changes may impact key evolutionary processes linked to population viability. This work will in this way provide unique insights into evolutionary and ecological factors affecting extinction risk, but the benefits will not be, therefore, circumscribed to the area of evolutionary biology; they will also have repercussions for conservation biology. Additionally, this research will uncover some of the far-reaching evolutionary implications of transgenerational effects for the evolution of phenotypes and, possibly, population viability. Finally, the project will provide excellent research opportunities for students, and it will also yield useful data for pest control. .