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Updated: Jun 21, 2026
07:37
Resurrection of Dormant Daphnia magna: Protocol and Applications
Published on: January 19, 2018
Evolutionary rescue can prevent extinction following environmental change.
1Biology Department, McGill University, Montreal, H3A 1B1 QC, Canada. graham.bell@mcgill.ca
Ecology Letters
|August 8, 2009
Summary
Evolutionary rescue (ER) is possible for populations facing rapid environmental change. Sufficiently large population sizes are critical for adaptation and preventing extinction, as demonstrated in yeast experiments.
Area of Science:
- Evolutionary biology
- Ecology
- Genetics
Background:
- Global change and biodiversity loss present urgent challenges.
- Rapid environmental shifts can outpace physiological adaptation and migration, leading to extinction.
- Evolutionary rescue (ER) theory posits that adaptation can prevent population collapse.
Purpose of the Study:
- To experimentally test the conditions for evolutionary rescue (ER).
- To investigate the roles of population size, genetic variation, and maladaptation in ER.
- To determine the speed at which populations can adapt to lethal environmental conditions.
Main Methods:
- Utilized experimental evolution with hundreds of yeast populations.
- Exposed populations to normally lethal salt concentrations.
- Manipulated population size and estimated the frequency of rescue mutations.
Main Results:
- Evolutionary rescue (ER) was observed, with population recovery occurring within 25 generations.
- A critical population size threshold was identified, necessary to overcome stochastic extinction.
- Larger populations were more likely to contain individuals with pre-existing resistance or new mutations enabling survival.
Conclusions:
- Rapid evolution is a key factor in the response of populations to environmental change.
- Sufficient population size is crucial for successful evolutionary rescue.
- Experimental evolution provides a powerful tool for understanding adaptation dynamics under environmental stress.
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