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Populations declining toward extinction can persist via genetic adaptation in a process called evolutionary rescue. Predicting evolutionary rescue has applications ranging from conservation biology to medicine, but requires understanding and integrating the multiple effects of a stressful environmental change on population processes. Here we derive a simple expression for how generation time, a key determinant of the rate of evolution, varies with population size during evolutionary rescue. Change in generation time is quantitatively predicted by comparing how intraspecific competition and the source of maladaptation each affect the rates of births and deaths in the population. Depending on the difference between two parameters quantifying these effects, the model predicts that populations may experience substantial changes in their rate of adaptation in both positive and negative directions, or adapt consistently despite severe stress. These predictions were then tested by comparison to the results of individual-based simulations of evolutionary rescue, which validated that the tolerable rate of environmental change varied considerably as described by analytical results. We discuss how these results inform efforts to understand wildlife disease and adaptation to climate change, evolution in managed populations and treatment resistance in pathogens.
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Evolutionary rescue via transgenerational plasticity: Evidence and implications for conservation
Abstract When a population experiences severe stress from a changing environment, evolution by natural selection can prevent its extinction, a process dubbed “evolutionary rescue.” However, evolution may be unable to track the sort ofrapidenvironmental change being experienced by many modern‐day populations. A potential solution is for organisms to respond to environmental change through phenotypic plasticity, which can buffer populations against change and thereby buy time for evolutionary rescue. In this review, we examine whether this process extends to situations in which the environmentally induced response is passed to offspring. As we describe, theoretical and empirical studies suggest that such “transgenerational plasticity” can increase population persistence. We discuss the implications of this process for conservation biology, outline potential limitations, and describe some applications. Generally, transgenerational plasticity may be effective at buying time for evolutionary rescue to occur.
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- Award ID(s):
- 1753865
- PAR ID:
- 10449318
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Evolution & Development
- Volume:
- 23
- Issue:
- 4
- ISSN:
- 1520-541X
- Format(s):
- Medium: X Size: p. 292-307
- Size(s):
- p. 292-307
- Sponsoring Org:
- National Science Foundation
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