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Updated: May 29, 2026
07:14
A Method to Study Adaptation to Left-Right Reversed Audition
Published on: October 29, 2018
Interfering waves of adaptation promote spatial mixing.
Erik A Martens1, Oskar Hallatschek
1Biophysics and Evolutionary Dynamics Group, Max Planck Institute for Dynamics and Self-Organization, 37073 Göttingen, Germany. erik.martens@ds.mpg.de
Genetics
|September 9, 2011
Summary
Asexual adaptation struggles with clonal interference in large populations. Spatial structure worsens this, but recombination and long-range migration can mitigate it, offering insights into microbial evolution.
Area of Science:
- Evolutionary biology
- Population genetics
- Theoretical ecology
Background:
- Asexual populations face challenges in accumulating beneficial mutations due to clonal interference.
- Clonal interference, where competing beneficial mutations hinder each other's fixation, is a significant factor in adaptation.
- The evolution of sex and recombination is hypothesized to be a response to clonal interference in well-mixed populations.
Purpose of the Study:
- To investigate clonal interference in spatially structured populations.
- To identify mechanisms that mitigate clonal interference in asexual adaptation.
- To determine the impact of spatial structure on adaptation speed and the role of migration and recombination.
Main Methods:
- Development of an evolutionary model for spatially structured populations.
- Analysis of clonal interference dynamics under uniform selection pressure.
- Mathematical modeling to derive scaling laws for adaptation speed and interference length.
Main Results:
- Clonal interference is significantly more prevalent in spatially structured populations compared to well-mixed ones.
- Adaptation speed in asexuals saturates with increasing habitat size beyond a characteristic interference length.
- The limiting adaptation speed scales with mutational supply (μ) as μ(1/2) in linear and μ(1/3) in planar habitats.
- Recombination and long-range migration are effective in reducing clonal competition in structured populations.
Conclusions:
- Spatial structure exacerbates clonal interference, slowing down asexual adaptation.
- A fundamental speed limit exists for asexual adaptation in structured populations, influenced by mutation rate and local density.
- Clonal interference likely drives genetic and spatial mixing in microbial colonies and biofilms, promoting adaptation and diversity.
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