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Updated: Apr 5, 2026
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Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
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Directional and disruptive selection in populations structured by class and continuous ontogeny under incomplete
Arthur Weyna1, Charles Mullon1, Laurent Lehmann1
1Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland.
Plos Computational Biology
|April 3, 2026
Summary
This study explores how fixed traits influence an organism's lifelong development and fitness, considering age and sex differences. It reveals how selection acts across different life stages, impacting evolution and diversification.
Area of Science:
- Evolutionary biology
- Developmental biology
- Population genetics
Background:
- Organisms change throughout their lives (ontogeny), affecting traits like size and condition.
- Understanding the evolution of these developmental traits is complex due to lifetime fitness effects and sex-specific differences.
Purpose of the Study:
- To analyze selection on non-plastic traits that shape ontogenetic trajectories.
- To understand how age and sex influence fitness consequences across an organism's lifespan.
Main Methods:
- Utilized invasion analysis to derive expressions for directional and disruptive selection.
- Decomposed selection into age- and class-specific components.
- Applied results to a model of growth under size-mediated sexual selection.
Main Results:
- Identified convergence-stable trait values and assessed their potential for evolutionary branching.
- Showcased how selection on growth rates varies across ages and sexes, influenced by genetic correlations and life history.
- Demonstrated how sex-specific trade-offs can drive disruptive selection on male growth, favoring alternative male life histories.
Conclusions:
- Adaptation is shaped by the interplay between development and population dynamics (demography).
- Provides tools to investigate how conflicts across ages and sexes influence aging, sexual dimorphism, and the evolution of diverse developmental strategies.
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