Adapt or perish: Evolutionary rescue in a gradually deteriorating environment
arXiv:2005.01625 · doi:10.1534/genetics.120.303624
Abstract
We investigate the evolutionary rescue of a microbial population in a gradually deteriorating environment, through a combination of analytical calculations and stochastic simulations. We consider a population destined for extinction in the absence of mutants, which can only survive if mutants sufficiently adapted to the new environment arise and fix. We show that mutants that appear later during the environment deterioration have a higher probability to fix. The rescue probability of the population increases with a sigmoidal shape when the product of the carrying capacity and of the mutation probability increases. Furthermore, we find that rescue becomes more likely for smaller population sizes and/or mutation probabilities if the environment degradation is slower, which illustrates the key impact of the rapidity of environment degradation on the fate of a population. We also show that our main conclusions are robust across various types of adaptive mutants, including specialist and generalist ones, as well as mutants modeling antimicrobial resistance evolution. We further express the average time of appearance of the mutants that do rescue the population and the average extinction time of those that do not. Our methods can be applied to other situations with continuously variable fitnesses and population sizes, and our analytical predictions are valid in the weak-to-moderate mutation regime.
arXiv comment36 pages, 18 figures
References in corpus (14)
- Coevolutionary Dynamics: From Finite to Infinite Populations
- Quantitative analyses of empirical fitness landscapes
- The Value of Information for Populations in Varying Environments
- Mutational pathway determines whether drug gradients accelerate evolution of drug-resistant cells
- Evolutionary game theory in growing populations
- Intrinsic noise in systems with switching environments
- The Impact of Environmental Fluctuations on Evolutionary Fitness Functions
- Evolution of a Fluctuating Population in a Randomly Switching Environment
- Resist or perish: fate of a microbial population subjected to a periodic presence of antimicrobial
- Tuning environmental timescales to evolve and maintain generalists
- Quantifying the role of population subdivision in evolution on rugged fitness landscapes
- Evolving generalists via dynamic sculpting of rugged landscapes
- Transitions in optimal adaptive strategies for populations in fluctuating environments
- Quantifying the impact of a periodic presence of antimicrobial on resistance evolution in a homogeneous microbial population of fixed size