Evolution in response to extreme events: good or bad? [article]

Kelsey Lyberger, Matthew Miles Osmond, Sebastian Schreiber
2020 bioRxiv   pre-print
Climate change is predicted to lead to more severe environmental perturbations, including storms and droughts, which act as strong selective agents. These extreme climatic events often act as pulse disturbances, where the new environment is transitory and populations that have evolved to the new environment may be maladapted to the historic environment when the extreme event ends. Using individual-based models and analytic approximations that fuse quantitative genetics and demography, we
more » ... mography, we explore how heritability and genetic variance affect population size and extinction risk under an extreme event. When an extreme event is sufficiently short in duration, greater heritability results in a stronger evolutionary response and greater maladaptation when the event ends, slowing population recovery and increasing the probability of extinction. Alternatively, when an extreme event is sufficiently long in duration, heritability often helps a population persist, a finding consistent with the classical evolutionary rescue theory. We also find that greater phenotypic variation slows down population recovery when events are mild, but lowers extinction risk when events are severe. Our results highlight the importance of accounting for the length as well as severity of a disturbance when assessing the role of evolution on population recovery.
doi:10.1101/2020.04.02.014951 fatcat:s6r6ezlcgvczfpqwrmtrnindby