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Updated: Jun 1, 2026
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Deferred Growth Inhibition Assay to Quantify the Effect of Bacteria-derived Antimicrobials on Competition
Published on: September 3, 2016
Phylogenetic limiting similarity and competitive exclusion
Cyrille Violle1, Diana R Nemergut, Zhichao Pu
1School of Biology, Georgia Institute of Technology, Atlanta, GA, USA. cyrille.violle@cefe.cnrs.fr
Ecology Letters
|June 16, 2011
Summary
Closely related species experience stronger competition, leading to faster exclusion and reduced populations. Phylogenetic relatedness, not just trait similarity, predicts competitive outcomes in ecological communities.
Area of Science:
- Ecology
- Evolutionary Biology
- Microbial Ecology
Background:
- The phylogenetic limiting similarity hypothesis, proposed by Darwin, posits that competition intensifies with closer phylogenetic relatedness.
- Despite its historical significance, empirical validation of this hypothesis remains limited.
Purpose of the Study:
- To experimentally test Darwin's hypothesis on phylogenetic limiting similarity.
- To investigate the role of phylogenetic relatedness in the outcomes of interspecific competition.
Main Methods:
- A multigenerational experiment was conducted using pairs of bacterivorous protist species.
- Competitive exclusion, population dynamics, and trait similarity (mouth size) were monitored.
Main Results:
- Competitive exclusion frequency and tempo increased with higher phylogenetic relatedness.
- Inferior competitors' abundance decreased more significantly between related species.
- Protist mouth size, a proxy for resource use, showed a significant phylogenetic signal.
- Phylogenetic relatedness was a stronger predictor of coexistence than trait similarity.
Conclusions:
- Experimental results support the phylogenetic limiting similarity hypothesis.
- Phylogenetic relatedness is a crucial factor in predicting competitive interactions and community structure.
- This study highlights the importance of evolutionary history in ecological dynamics.
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