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Towards a mechanistic understanding of competence: a missing link in diversity–disease research

Published online by Cambridge University Press:  10 June 2020

Tara E. Stewart Merrill Open the ORCID record for Tara E. Stewart Merrill [Opens in a new window]  and
Pieter T. J. Johnson Open the ORCID record for Pieter T. J. Johnson [Opens in a new window]
Tara E. Stewart Merrill*
Affiliation:
Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO80309, USA
Pieter T. J. Johnson
Affiliation:
Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO80309, USA
*
Author for correspondence: Tara E. Stewart Merrill, E-mail: [email protected]
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Abstract

Biodiversity loss may increase the risk of infectious disease in a phenomenon known as the dilution effect. Circumstances that increase the likelihood of disease dilution are: (i) when hosts vary in their competence, and (ii) when communities disassemble predictably, such that the least competent hosts are the most likely to go extinct. Despite the central role of competence in diversity–disease theory, we lack a clear understanding of the factors underlying competence, as well as the drivers and extent of its variation. Our perspective piece encourages a mechanistic understanding of competence and a deeper consideration of its role in diversity–disease relationships. We outline current evidence, emerging questions and future directions regarding the basis of competence, its definition and measurement, the roots of its variation and its role in the community ecology of infectious disease.

Keywords

Competencedilution effectdiversity–diseaseintraspecific variation
Type
Review Article
Information
Parasitology , Volume 147 , Issue 11 , September 2020 , pp. 1159 - 1170
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Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press

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