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Updated: Jun 23, 2026
08:51
Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks
Published on: May 13, 2016
Can gene flow have negative demographic consequences? Mixed evidence from stream threespine stickleback
Jean-Sébastien Moore1, Andrew P Hendry
1Redpath Museum, Montreal, Quebec, Canada. jsmoore@zoology.ubc.ca
Summary
High gene flow from lakes may negatively impact stream fish populations, but evidence is mixed. This study on threespine stickleback found limited support for gene flow causing local range limits despite maladaptation.
Area of Science:
- Ecology
- Evolutionary Biology
- Population Genetics
Background:
- Dispersal and gene flow can influence population dynamics, with potential negative effects on population size and range limits.
- Empirical evidence for negative impacts of gene flow on natural populations remains scarce.
- Stream populations of threespine stickleback (Gasterosteus aculeatus L.) exhibit maladaptation due to high gene flow from adjacent lakes.
Purpose of the Study:
- To investigate the potential negative effects of gene flow on population size and local range limits in a stream stickleback population.
- To test theoretical predictions regarding peripheral populations, local adaptation, and selection pressures.
- To determine if gene flow constrains population size and contributes to range boundaries.
Main Methods:
- Field experiments involving transplanting stickleback to assess home-site advantage.
- Mark-recapture studies to evaluate directional selection on phenotypes.
- Mark-recapture experiments to quantify dispersal rates and demographic effects.
Main Results:
- A weak home-site advantage was observed in the peripheral stream population.
- Directional selection favoring stream-adapted phenotypes occurred in one of two years.
- Dispersal was limited, suggesting minimal positive demographic contributions from gene flow.
Conclusions:
- Gene flow constrains morphological maladaptation in the studied stream stickleback population.
- The evidence for gene flow contributing to population size reduction and range limits is inconclusive.
- Further research is needed to understand the complex interplay of factors influencing the evolution of species' ranges.
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