Lotka-Volterra pairwise modeling fails to capture diverse pairwise microbial interactions

  1. Babak Momeni  Is a corresponding author
  2. Li Xie
  3. Wenying Shou  Is a corresponding author
  1. Boston College, United States
  2. Fred Hutchinson Cancer Research Center, United States


Pairwise models are commonly used to describe many-species communities. In these models, an individual receives additive fitness effects from pairwise interactions with each species in the community ('additivity assumption'). All pairwise interactions are typically represented by a single equation where parameters reflect signs and strengths of fitness effects ('universality assumption'). Here, we show that a single equation fails to qualitatively capture diverse pairwise microbial interactions. We build mechanistic reference models for two microbial species engaging in commonly-found chemical-mediated interactions, and attempt to derive pairwise models. Different equations are appropriate depending on whether a mediator is consumable or reusable, whether an interaction is mediated by one or more mediators, and sometimes even on quantitative details of the community (e.g. relative fitness of the two species, initial conditions). Our results, combined with potential violation of the additivity assumption in many-species communities, suggest that pairwise modeling will often fail to predict microbial dynamics.

Article and author information

Author details

  1. Babak Momeni

    Department of Biology, Boston College, Chestnut Hill, United States
    For correspondence
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1271-5196
  2. Li Xie

    Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
    Competing interests
    No competing interests declared.
  3. Wenying Shou

    Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
    For correspondence
    Competing interests
    Wenying Shou, Reviewing editor, eLife.


Boston College

  • Babak Momeni

NIH Office of the Director

  • Babak Momeni
  • Li Xie

W. M. Keck Foundation

  • Babak Momeni

Fred Hutchinson Cancer Research Center

  • Li Xie

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Bruce Levin

Publication history

  1. Received: January 11, 2017
  2. Accepted: March 18, 2017
  3. Accepted Manuscript published: March 28, 2017 (version 1)
  4. Accepted Manuscript updated: April 3, 2017 (version 2)
  5. Version of Record published: June 13, 2017 (version 3)


© 2017, Momeni et al.

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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  1. Babak Momeni
  2. Li Xie
  3. Wenying Shou
Lotka-Volterra pairwise modeling fails to capture diverse pairwise microbial interactions
eLife 6:e25051.
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