1. Computational and Systems Biology
  2. Ecology
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Community-level cohesion without cooperation

  1. Mikhail Tikhonov  Is a corresponding author
  1. Harvard University, United States
Research Article
  • Cited 37
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Cite this article as: eLife 2016;5:e15747 doi: 10.7554/eLife.15747


Recent work draws attention to community-community encounters ('coalescence') as likely an important factor shaping natural ecosystems. This work builds on MacArthur's classic model of competitive coexistence to investigate such community-level competition in a minimal theoretical setting. It is shown that the ability of a species to survive a coalescence event is best predicted by a community-level 'fitness' of its native community rather than the intrinsic performance of the species itself. The model presented here allows formalizing a macroscopic perspective whereby a community harboring organisms at varying abundances becomes equivalent to a single organism expressing genes at different levels. While most natural communities do not satisfy the strict criteria of multicellularity developed by multi-level selection theory, the effective cohesion described here is a generic consequence of resource partitioning, requires no cooperative interactions, and can be expected to be widespread in microbial ecosystems.

Article and author information

Author details

  1. Mikhail Tikhonov

    Center of Mathematical Sciences and Applications, Harvard University, Cambridge, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Carl T Bergstrom, University of Washington, United States

Publication history

  1. Received: March 2, 2016
  2. Accepted: June 10, 2016
  3. Accepted Manuscript published: June 16, 2016 (version 1)
  4. Version of Record published: July 15, 2016 (version 2)


© 2016, Tikhonov

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.


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