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Effective fitness under fluctuating selection with genetic drift
1Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA.
G3 (Bethesda, Md.)
|October 10, 2023
Summary
Geometric mean fitness can be misleading when genetic drift influences fluctuating selection. This study introduces effective fitness, a new measure that accurately reflects fluctuating selection
Area of Science:
- Evolutionary biology
- Population genetics
Background:
- Natural environments fluctuate, causing temporal variation in mutant fitness.
- Geometric mean fitness is a common but potentially misleading metric for fluctuating selection.
Purpose of the Study:
- To evaluate the accuracy of geometric mean fitness under fluctuating selection with genetic drift.
- To propose and validate a new metric, effective fitness, for this scenario.
Main Methods:
- Mathematical proofs were used to analyze fitness measures.
- Computer simulations were employed to test the proposed metric.
Main Results:
- Geometric mean fitness does not accurately represent the overall effect of fluctuating selection in the presence of genetic drift.
- Effective fitness provides a more accurate measure of fluctuating selection's impact with drift.
Conclusions:
- Effective fitness is a superior metric for assessing fluctuating selection under genetic drift.
- This finding has implications for understanding evolutionary dynamics in variable environments.
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