Symbiont switching and alternative resource acquisition strategies drive mutualism breakdown

  title={Symbiont switching and alternative resource acquisition strategies drive mutualism breakdown},
  author={Gijsbert D. A. Werner and Johannes H. C. Cornelissen and William K. Cornwell and Nadejda A. Soudzilovskaia and Jens Kattge and Stuart Andrew West and E. Toby Kiers},
  journal={Proceedings of the National Academy of Sciences},
  pages={5229 - 5234}
Significance Cooperative interactions among species—mutualisms—are major sources of evolutionary innovation. However, despite their importance, two species that formerly cooperated sometimes cease their partnership. Why do mutualisms break down? We asked this question in the partnership between arbuscular mycorrhizal (AM) fungi and their plant hosts, one of the most ancient mutualisms. We analyze two potential trajectories toward evolutionary breakdown of their cooperation, symbiont switching… 

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