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04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Fluctuating population dynamics promotes the evolution of phenotypic plasticity
Richard Svanbäck1, Mario Pineda-Krch, Michael Doebeli
1Department of Zoology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. richard.svanback@ebc.uu.se
The American Naturalist
|June 13, 2009
Summary
Evolutionary branching and phenotypic plasticity are two responses to disruptive selection. Phenotypic plasticity is favored in unstable environments, while evolutionary branching is favored in stable ones, impacting species diversification.
Area of Science:
- Evolutionary biology
- Theoretical ecology
- Population dynamics
Background:
- Disruptive selection can lead to phenotypic diversification.
- Evolutionary branching and phenotypic plasticity are two key responses to disruptive selection.
- Environmental stability influences whether genetic or plastic diversification is favored.
Purpose of the Study:
- Investigate the interplay between evolutionary branching and phenotypic plasticity.
- Model these processes within a predator-prey system with fluctuating population dynamics.
- Determine conditions favoring each diversification strategy.
Main Methods:
- Developed a predator-prey model incorporating both evolutionary branching and phenotypic plasticity.
- Simulated ecological dynamics with varying degrees of population cycles.
- Analyzed the conditions under which each evolutionary strategy dominates.
Main Results:
- Phenotypic plasticity was favored during pronounced predator-prey cycles (unstable environments).
- Evolutionary branching was favored during more stable ecological dynamics.
- Trimorphisms, including plastic generalists and specialist branches, emerged at intermediate cycle levels.
Conclusions:
- Ecological and evolutionary dynamics are intricately linked.
- Population dynamics significantly influence diversification strategies.
- Considering population dynamics is crucial for understanding evolutionary diversification in nature.
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