Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

Host and Parasite Counteradaptations: An Example from a Freshwater Snail

Dennis J. Minchella, Bonnie K. Leathers, Kenneth M. Brown and James N. McNair
The American Naturalist
Vol. 126, No. 6 (Dec., 1985), pp. 843-854
Stable URL: http://www.jstor.org/stable/2461259
Page Count: 12
  • Read Online (Free)
  • Download ($19.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Host and Parasite Counteradaptations: An Example from a Freshwater Snail
Preview not available

Abstract

Host-parasite interactions may lead to a variety of outcomes. Trematode infection of pulmonate snails is often associated with increased growth and/or survivorship of snail hosts. We use the freshwater pulmonate Lymnaea elodes and its trematode parasites to test whether this increase is a parasite adaptation, a host adaptation, or a side effect that serves no adaptive function for either participant. Field experiments indicate that trematode parasitism significantly reduces host fecundity and causes a temporary elevation and subsequent reduction in host growth. A 2-yr field survey of the prevalence of trematode infection in three snail populations revealed a significant positive relationship between shell size and prevalence. Apparently, L. elodes does not outlive its trematode infections. When survey data are compared with theoretical curves generated from a simple model of the system, it appears that trematode parasitism increases the survivorship of infected snails. Overall, the results suggest that increased survivorship in trematode-infected L. elodes is a parasite strategy for providing a stable, longterm resource for the parasite.

Page Thumbnails

  • Thumbnail: Page 
[843]
    [843]
  • Thumbnail: Page 
844
    844
  • Thumbnail: Page 
845
    845
  • Thumbnail: Page 
846
    846
  • Thumbnail: Page 
847
    847
  • Thumbnail: Page 
848
    848
  • Thumbnail: Page 
849
    849
  • Thumbnail: Page 
850
    850
  • Thumbnail: Page 
851
    851
  • Thumbnail: Page 
852
    852
  • Thumbnail: Page 
853
    853
  • Thumbnail: Page 
854
    854