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Daily Transfers, Archiving Populations, and Measuring Fitness in the Long-Term Evolution Experiment with Escherichia coli
Published on: August 18, 2023
Evolution with stochastic fitnesses: a role for recombination
Oana Carja1, Uri Liberman, Marcus W Feldman
1Department of Biology, Stanford University, Stanford, CA, 94305, United States. oana.carja@gmail.com
Theoretical Population Biology
|March 23, 2013
Summary
Evolutionary adaptation to changing environments depends on fitness variation. Recombination between genes influencing phenotype and its variation can alter evolutionary trajectories, especially with epigenetic factors.
Area of Science:
- Evolutionary biology
- Population genetics
- Genetics
Background:
- Phenotypic adaptation to fluctuating environments is crucial for evolutionary success.
- Evolutionary dynamics are influenced by both mean fitness and fitness variation across generations.
- Stochastic epigenetic variation plays a role in adaptation by modifying geometric mean fitness.
Purpose of the Study:
- To investigate the impact of recombination between mean- and variance-modifying genes on evolutionary adaptation.
- To explore how recombination interacts with epigenetic variation and environmental fluctuations.
- To understand the long-term evolutionary trajectories in systems with and without recombination.
Main Methods:
- Development of a population genetic model.
- Analysis of evolutionary dynamics under varying environmental regimes and fitness landscapes.
- Inclusion of recombination between genes controlling phenotypic mean and variance.
Main Results:
- Recombination between mean- and variance-modifiers can lead to complex evolutionary dynamics.
- Interactions between recombination, epigenetic variation, and environmental fluctuations significantly alter evolutionary outcomes.
- The geometric mean principle's influence is modulated by recombination.
Conclusions:
- Recombination is a key factor shaping adaptation in fluctuating environments.
- Stochastic epigenetic variation, modulated by recombination, is important for evolutionary trajectories.
- The study highlights the intricate interplay between genetic architecture, epigenetic mechanisms, and environmental unpredictability in evolution.
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