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Published on: December 9, 2015
A structured coalescent process for seasonally fluctuating populations
Max Shpak1, John Wakeley, Daniel Garrigan
1Department of Biological Sciences, University of Texas at El Paso, El Paso, Texas 79968, USA. mshpak@utep.edu
Evolution; International Journal of Organic Evolution
|November 10, 2009
Summary
Seasonal population fluctuations impact genetic variation. While studies show increased variation in growing seasons, it
Area of Science:
- Population genetics
- Evolutionary biology
- Ecological dynamics
Background:
- Short-lived organisms exhibit seasonal population size and metapopulation structure changes.
- Favorable seasons lead to isolated demes, while later generations experience increased gene flow.
- Seasonal fluctuations can alter genetic variation between early and late season populations.
Purpose of the Study:
- Investigate genetic variation patterns under seasonal population fluctuations.
- Analyze the structured coalescent process with seasonal dynamics.
- Compare simulation results with empirical observations of seasonal allelism variation.
Main Methods:
- Numerical analysis of exact state equations.
- Analytical approximations using timescale separation.
- Individual-based simulations of structured coalescent processes.
Main Results:
- Observed an increase in genetic variation during growing seasons.
- The increase in genetic variation was less pronounced than empirical observations.
- Seasonal fluctuations influence genetic variation and population structure.
Conclusions:
- Neutral processes alone may not fully explain observed temporal genetic variation patterns.
- Selection against deleterious lethals could contribute to seasonal variation patterns.
- Further research is needed to disentangle neutral and selection-driven effects on genetic variation.
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