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Following the Dynamics of Structural Variants in Experimentally Evolved Populations
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Increased genetic variance after a population bottleneck.

H L Carson1

  • 1Hampton Carson is at the Dept of Genetics, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96822, USA.

Trends in Ecology & Evolution
|January 15, 2011
PubMed
Summary
This summary is machine-generated.

Population bottlenecks can surprisingly increase genetic variance available for selection, contrary to conventional views. This genetic variation can promote adaptation and speciation, challenging established evolutionary theories.

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Area of Science:

  • Evolutionary biology
  • Population genetics

Background:

  • Conventional theory posits population bottlenecks reduce genetic variability, threatening population viability.
  • Empirical evidence from Drosophila and housefly populations challenges this view.

Purpose of the Study:

  • To investigate the impact of severe population bottlenecks on genetic variance available for selection.
  • To explore the mechanisms by which bottlenecks might increase genetic variance.

Main Methods:

  • Empirical studies on Drosophila and housefly populations.
  • Theoretical modeling of genetic variance dynamics.

Main Results:

  • Severe bottlenecks can increase, rather than decrease, genetic variance available to selection.
  • This increase may stem from the conversion of epistatic variance to additive variance.
  • Effects are pronounced in quantitative traits, disrupting covariance matrices.

Conclusions:

  • Population bottlenecks, particularly founder events, can promote adaptation and speciation by releasing genetic variation.
  • The study challenges traditional understanding of bottleneck effects on genetic diversity.