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Molecular diversity after a range expansion in heterogeneous environments
Daniel Wegmann1, Mathias Currat, Laurent Excoffier
1Computational and Molecular Population Genetics Laboratory, Zoological Institute, University of Bern, Switzerland.
Genetics
|October 10, 2006
Summary
Environmental heterogeneity impacts species' genetic diversity during range expansions. Heterogeneous environments reduce genetic diversity within populations and increase differentiation, especially in low-density metapopulations.
Area of Science:
- Ecology
- Evolutionary Biology
- Population Genetics
Background:
- Range expansions are common evolutionary events.
- Previous models often overlooked environmental heterogeneity.
- Range expansions create distinct molecular diversity patterns compared to demographic expansions.
Purpose of the Study:
- To model range expansion in heterogeneous environments.
- To link ecological parameters to molecular diversity.
- To investigate the impact of spatial and temporal environmental variations.
Main Methods:
- Developed a metapopulation model incorporating environmental heterogeneity.
- Modeled carrying capacities using a gamma distribution.
- Conducted extensive simulations to analyze genetic diversity patterns.
Main Results:
- Environmental heterogeneity reduces genetic diversity within demes.
- Increased population differentiation observed in heterogeneous environments.
- Low-density metapopulations are more sensitive to environmental heterogeneity.
Conclusions:
- Spatial heterogeneity has a greater impact on genetic diversity than temporal heterogeneity.
- Environmental heterogeneity significantly influences molecular diversity patterns.
- Metapopulation density modulates the effects of environmental variations.
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