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Related Experiment Video

Updated: Nov 6, 2025

Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks

Microinjection for Transgenesis and Genome Editing in Threespine Sticklebacks

Published on: May 13, 2016

Population Structure Limits Parallel Evolution in Sticklebacks.

Bohao Fang¹, Petri Kemppainen¹, Paolo Momigliano¹

¹Ecological Genetics Research Unit, Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland.

Molecular Biology and Evolution

|May 6, 2021

Summary

This summary is machine-generated.

Population subdivision limits local adaptation. Stickleback species with lower genetic diversity and more isolation show less parallel evolution, supporting theories on gene flow and population size impacts.

Keywords:

adaptation genetic diversity isolation by distance parallel evolution population differentiation stickleback

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Area of Science:

Evolutionary Biology
Population Genetics
Genomics

Background:

Population genetic theory posits that small effective population sizes (Ne) and limited gene flow impede local adaptation.
Parallel evolution, the independent evolution of similar traits via shared genetic mechanisms, is predicted to be less probable under such conditions.

Purpose of the Study:

To investigate the influence of population size and gene flow on local adaptation and parallel evolution.
To compare the genomic patterns of adaptation in two ecologically similar, co-distributed stickleback species: Gasterosteus aculeatus and Pungitius pungitius.

Main Methods:

Comparative genomic study analyzing genetic diversity, differentiation, and patterns of selection.
Examined single nucleotide polymorphisms (SNPs) and genomic regions showing evidence of selection across multiple freshwater populations.

Main Results:

Pungitius pungitius displayed lower genetic diversity and higher genetic differentiation than Gasterosteus aculeatus.
G. aculeatus showed significantly more evidence of parallel evolution (2,996 SNPs in 26 regions) compared to P. pungitius (379 SNPs in 9 regions).
Parallel evolution in G. aculeatus involved older, divergent haplotypes, while P. pungitius adaptation involved younger haplotypes.

Conclusions:

Population connectivity and genetic drift are critical factors influencing standing genetic variation and its distribution.
Population subdivision demonstrably restricts local adaptation and reduces the probability of parallel evolution, aligning with theoretical predictions.