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Updated: Jul 2, 2026
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Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
On indirect genetic effects in structured populations.
A F Agrawal1, E D Brodie, M J Wade
1Department of Biology and Center for the Integrative Study of Animal Behavior, Indiana University, Bloomington, Indiana 47405-3700, USA. aagrawal@bio.indiana.edu
The American Naturalist
|August 19, 2008
Summary
Indirect genetic effects (IGEs) can evolve in structured populations, influencing trait evolution and potentially opposing direct selection. Nonlinear social interactions in metapopulations significantly alter evolutionary trajectories and multilevel selection dynamics.
Area of Science:
- Evolutionary biology
- Quantitative genetics
- Population genetics
Background:
- Indirect genetic effects (IGEs) arise when an individual's traits are influenced by the genes of social partners.
- IGEs can lead to the evolution of environmental variance and alter the dynamics of interacting phenotypes.
- Previous models demonstrated IGEs' impact on trait evolution but were limited in scope.
Purpose of the Study:
- To extend IGE theory to metapopulations by incorporating nonlinear interactions and genetic structure.
- To investigate how population subdivision and nonlinear social effects jointly influence evolutionary dynamics.
- To examine the role of IGEs in multilevel selection, considering individual and group selection.
Main Methods:
- Theoretical modeling of indirect genetic effects in structured populations.
- Inclusion of nonlinear social interactions and population subdivision.
- Analysis of evolutionary response under individual and group selection.
Main Results:
- Population subdivision and nonlinear interactions amplify the importance of IGEs.
- Genetic structure links interacting phenotypes and effector traits, even without direct genetic correlations.
- Evolutionary responses can oppose direct selection due to nonlinear social effects in subdivided populations.
- Nonlinear social effects cause selection interference at multiple levels, potentially reversing predicted evolutionary outcomes.
Conclusions:
- IGEs are crucial in metapopulations, especially with nonlinear interactions and genetic structure.
- Population structure and nonlinear social dynamics can lead to counterintuitive evolutionary trajectories.
- Multilevel selection dynamics are significantly impacted by IGEs, necessitating consideration of selection interference.
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