Affordable Access

Publisher Website

Host allometry influences the evolution of parasite host-generalism: theory and meta-analysis.

  • Walker, Josephine G1, 2
  • Hurford, Amy3, 4
  • Cable, Jo5
  • Ellison, Amy R5
  • Price, Stephen J6
  • Cressler, Clayton E7
  • 1 School of Biological Sciences, University of Bristol, Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK.
  • 2 School of Social and Community Medicine, University of Bristol, Oakfield House, Oakfield Grove, Bristol BS8 2BN, UK.
  • 3 Department of Biology, Memorial University of Newfoundland, St John's, Newfoundland, Canada A1B 3X9. , (Canada)
  • 4 Department of Mathematics and Statistics, Memorial University of Newfoundland, St John's, Newfoundland, Canada A1C 5S7. , (Canada)
  • 5 School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK.
  • 6 UCL Genetics Institute, Gower Street, London WC1E 6BT, UK.
  • 7 School of Biological Sciences, University of Nebraska-Lincoln, 424 Manter Hall, 1104 T St, Lincoln, NE 68588-0118, USA [email protected]
Published Article
Philosophical Transactions of The Royal Society B Biological Sciences
The Royal Society
Publication Date
May 05, 2017
DOI: 10.1098/rstb.2016.0089
PMID: 28289257


Parasites vary widely in the diversity of hosts they infect: some parasite species are specialists-infecting just a single host species, while others are generalists, capable of infecting many. Understanding the factors that drive parasite host-generalism is of basic biological interest, but also directly relevant to predicting disease emergence in new host species, identifying parasites that are likely to have unidentified additional hosts, and assessing transmission risk. Here, we use mathematical models to investigate how variation in host body size and environmental temperature affect the evolution of parasite host-generalism. We predict that parasites are more likely to evolve a generalist strategy when hosts are large-bodied, when variation in host body size is large, and in cooler environments. We then explore these predictions using a newly updated database of over 20 000 fish-macroparasite associations. Within the database we see some evidence supporting these predictions, but also highlight mismatches between theory and data. By combining these two approaches, we establish a theoretical basis for interpreting empirical data on parasites' host specificity and identify key areas for future work that will help untangle the drivers of parasite host-generalism.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'. © 2017 The Authors.

Report this publication


Seen <100 times