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Related Experiment Video

Updated: Apr 25, 2026

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

Fixation in finite populations evolving in fluctuating environments.

Peter Ashcroft¹, Philipp M Altrock², Tobias Galla³

¹Theoretical Physics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK.

Journal of the Royal Society, Interface

|August 29, 2014

Summary

A changing environment can surprisingly boost mutant survival in evolutionary games. Dynamic environments, by exploiting environmental noise, can increase fixation probability beyond static conditions.

Keywords:

evolutionary dynamics fluctuating environments stochastic processes

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Area of Science:

Evolutionary biology
Population dynamics
Theoretical ecology

Background:

Environmental changes significantly influence evolutionary selection.
Population dynamics are governed by birth and death rates, which can fluctuate over time.
Environmental states can be modeled using Markov processes.

Purpose of the Study:

To develop a general theory for mutant fixation probability and fixation times in changing environments.
To apply this theory to evolutionary games with time-varying payoff structures.
To investigate the impact of environmental noise on evolutionary dynamics.

Main Methods:

Developing a general mathematical theory for fixation probability and fixation times.
Applying the theory to evolutionary games with time-dependent payoff matrices.
Analyzing population dynamics driven by birth and death events in a Markovian environment.

Main Results:

A dynamic environment can increase mutant fixation probability beyond that of static environments.
Environmental noise can be exploited by mutants, leading to higher fixation probabilities.
Two approximations for stationary distributions were found, applicable to rapid and slow environmental switching.

Conclusions:

Environmental fluctuations can create novel evolutionary dynamics and outcomes.
The study provides a theoretical framework to understand evolution in non-stationary environments.
The findings have implications for evolutionary game theory and understanding adaptation in fluctuating conditions.