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Updated: Mar 30, 2026
09:17
Investigation of Plant Interactions Across Common Mycorrhizal Networks Using Rotated Cores
Published on: March 26, 2019
13.5K
Rethinking "mutualism" in diverse host-symbiont communities
Alexandra A Mushegian1, Dieter Ebert1
1Zoological Institute, University of Basel, Switzerland.
Summary
Studies on bacteria benefiting eukaryotes are common, but host effects on microbial fitness are understudied. This research proposes redefining "mutualism" and "parasitism" for pairwise interactions, and reframing complex microbial communities as ecological systems.
Area of Science:
- Microbial Ecology
- Evolutionary Biology
- Symbiosis Research
Background:
- Documented instances of bacteria benefiting eukaryotic hosts are increasing.
- Research on the reciprocal effects of eukaryotic hosts on microbial fitness remains scarce.
- The terms "mutualism" and "parasitism" are often applied broadly, even without demonstrated reciprocity or when diverse microbial communities are involved.
Purpose of the Study:
- To critically evaluate the application of "mutualism" and "parasitism" in the context of host-microbe interactions.
- To propose a framework for studying symbiosis in complex microbial communities.
- To emphasize the importance of understanding microbial fitness within host-associated communities.
Main Methods:
- Conceptual analysis of symbiosis terminology and its application.
- Proposal for re-formulating symbiosis questions within community ecology and ecosystem function paradigms.
- Emphasis on empirical measurement of fitness effects in pairwise interactions.
Main Results:
- Current definitions of mutualism and parasitism may be inadequate for diverse microbial communities.
- A proposed re-framing allows investigation of microbial interactions without assuming reciprocity.
- Understanding microbial fitness is essential for comprehending eukaryote evolution.
Conclusions:
- Reserve "mutualism" and "parasitism" for verified pairwise interactions independent of other species.
- Treat complex host-associated microbial communities as ecological systems to study specificity, transmission, and co-evolution.
- Investigating the fitness of host-associated bacteria is critical for advancing symbiosis research and understanding eukaryote evolution.
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