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Updated: May 30, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
An equilibrium for phenotypic variance in fluctuating environments owing to epigenetics
1Department of Biology, Stanford University, Stanford, CA 94305, USA. ocarja@stanford.edu
Journal of the Royal Society, Interface
|August 19, 2011
Summary
Epigenetic variation influences how organisms adapt to changing environments. This study shows that while populations may initially increase phenotypic variance, they often evolve towards a stable equilibrium of variability.
Area of Science:
- Evolutionary biology
- Genetics
- Developmental biology
Background:
- Population genetics studies the link between random environments and genetic/phenotypic variability.
- Epigenetic variation may mediate interactions between environmental factors and phenotypic outcomes.
Purpose of the Study:
- To model epigenetic plasticity during development.
- To investigate genetic regulators affecting phenotypic variance without altering the mean phenotype.
Main Methods:
- Computational simulation of epigenetic plasticity.
- Analysis of genetic regulators influencing phenotypic variance.
Main Results:
- Variance-increasing alleles can be out-competed by variance-reducing alleles.
- Populations evolve towards an equilibrium phenotypic variability.
- This equilibrium is sensitive to mutation rates, fitness landscapes, and environmental fluctuations.
Conclusions:
- Epigenetic mechanisms contribute to adaptive evolution in fluctuating environments.
- Evolutionary dynamics can lead to stable levels of phenotypic variability.
- The balance between variance increase and reduction is crucial for adaptation.
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