Extreme climate events such as hurricanes, droughts, and floods act as drivers of ecological and evolutionary change. These events are expected to increase in intensity and frequency in the future. We explore how a population's ability to rapidly evolve affects population size and extinction risk in the context of extreme events of varying intensity, duration, and frequency. These explorations are based on analytical approximations and numerical simulations of an individual-based model that fuses the infinitesimal model of population genetics with a density-dependent demography model.
Results/Conclusions
We find that 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. Also, when populations experience repeated extreme events, heritability increases extinction risk, unless the events are temporally autocorrelated. Our results highlight the importance of accounting for the intensity, duration, and frequency of extreme events when assessing the role of evolution on population recovery.