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Published on: August 18, 2023
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Counterintuitive properties of evolutionary measures: A stochastic process study in cyclic population structures with
Hossein Nemati1, Kamran Kaveh2, Mohammad Reza Ejtehadi1
1Sharif University of Technology, Physics Department, Iran.
Journal of Theoretical Biology
|February 24, 2023
Summary
Spatial variations in resources significantly alter mutant success in structured populations. Increased heterogeneity can even make deleterious mutants beneficial, impacting evolutionary dynamics.
Area of Science:
- Evolutionary Biology
- Population Genetics
- Mathematical Biology
Background:
- Local environmental interactions critically influence mutant success in structured populations.
- Spatial resource heterogeneity can unpredictably alter evolutionary outcomes by modifying local fitness landscapes.
Purpose of the Study:
- To investigate how local environmental variations in structured populations affect selection conditions and fixation probabilities of mutants.
- To analyze the impact of spatial resource patterns on evolutionary dynamics in linear network structures.
Main Methods:
- Modeling a constant population birth-death process on linear graph structures.
- Calculating fixation probability and fixation times under varying fitness heterogeneity and resource distribution periods.
- Analyzing the effects of spatial scale (period T) and fitness shifts.
Main Results:
- Fixation probability is sensitive to both the degree of fitness heterogeneity and the spatial scale (period T) of resource variation.
- Conditions were identified where previously deleterious mutants become beneficial with increased fitness heterogeneity.
- Simultaneous fixation probabilities exceeding neutral expectations were observed, correlating with increased fixation times, suggesting potential coexistence.
Conclusions:
- Spatial resource heterogeneity is a crucial factor in evolutionary dynamics, capable of reversing selection pressures.
- The spatial scale and phase of resource distribution significantly influence mutant fixation probabilities and population dynamics.
- These findings highlight the complex interplay between local environments and evolutionary trajectories in structured populations.
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