Please use this identifier to cite or link to this item:
Appears in Collections:Biological and Environmental Sciences Journal Articles
Peer Review Status: Refereed
Title: Predators and patterns of within-host growth can mediate both among-host competition and the evolution of transmission potential of parasites
Author(s): Auld, Stuart
Hall, Spencer R
Houslay Ochs, Jessica
Sebastian, Mathew
Duffy, Meghan A
Contact Email:
Keywords: parasitic castrators
virulence evolution
parasite competition
obligate killers
Issue Date: Aug-2014
Date Deposited: 29-Jul-2014
Citation: Auld S, Hall SR, Houslay Ochs J, Sebastian M & Duffy MA (2014) Predators and patterns of within-host growth can mediate both among-host competition and the evolution of transmission potential of parasites. American Naturalist, 184 (S1), pp. S77-S90.
Abstract: Parasite prevalence shows tremendous spatiotemporal variation. Theory indicates that this variation might stem from life-history characteristics of parasites and key ecological factors. Here, we illustrate how the interaction of an important predator and the schedule of transmission potential of two parasites can explain parasite abundance. A field survey showed that a noncastrating fungus (Metschnikowia bicuspidata) commonly infected a dominant zooplankton host (Daphnia dentifera), while a castrating bacterial parasite (Pasteuria ramosa) was rare. This result seemed surprising given that the bacterium produces many more infectious propagules (spores) than the fungus upon host death. The fungus's dominance can be explained by the schedule of within-host growth of parasites (i.e., how transmission potential changes over the course of infection) and the release of spores from "sloppy" predators (Chaoborus spp., who consume Daphnia prey whole and then later regurgitate the carapace and parasite spores). In essence, sloppy predators create a niche that the faster-schedule fungus currently occupies. However, a selection experiment showed that the slower-schedule bacterium can evolve into this faster-schedule, predator-mediated niche (but pays a cost in maximal spore yield to do so). Hence, our study shows how parasite life history can interact with predation to strongly influence the ecology, epidemiology, and evolution of infectious disease.
DOI Link: 10.1086/676927
Rights: This item has been embargoed for a period. During the embargo please use the Request a Copy feature at the foot of the Repository record to request a copy directly from the author. You can only request a copy if you wish to use this work for your own research or private study. Publisher policy allows this work to be made available in this repository. Published in The American Naturalist, Vol. 184, No. S1, August 2014 by University of Chicago Press. The original publication is available at:

Files in This Item:
File Description SizeFormat 
Auldetal2014AmNat.pdfFulltext - Published Version717.31 kBAdobe PDFView/Open

This item is protected by original copyright

Items in the Repository are protected by copyright, with all rights reserved, unless otherwise indicated.

The metadata of the records in the Repository are available under the CC0 public domain dedication: No Rights Reserved

If you believe that any material held in STORRE infringes copyright, please contact providing details and we will remove the Work from public display in STORRE and investigate your claim.