Genetic drift opposes mutualism during spatial population expansion

@article{Mller2014GeneticDO,
  title={Genetic drift opposes mutualism during spatial population expansion},
  author={Melanie J. I. M{\"u}ller and Beverly I. Neugeboren and David R. Nelson and Andrew W. Murray},
  journal={Proceedings of the National Academy of Sciences},
  year={2014},
  volume={111},
  pages={1037 - 1042}
}
Significance Species expand from where they evolved or migrate in response to climate change. Such spatial expansions can impede mutualistic interactions (beneficial for both partners). Mutualism selects for species coexistence and genetic diversity, but spatial expansion creates regions of low diversity due to repeated founder effects. We show both theoretically and experimentally, using the colony expansion of cross-feeding yeast as a model system, that a critical mutualistic strength is… 
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