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.

Effects of Predation on Life-History Evolution in Utah Chub (Gila atraria)

Jerald B. Johnson and Mark C. Belk
Copeia
Vol. 1999, No. 4 (Dec. 17, 1999), pp. 948-957
DOI: 10.2307/1447970
Stable URL: http://www.jstor.org/stable/1447970
Page Count: 10
  • Read Online (Free)
  • Download ($12.00)
  • 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.
Effects of Predation on Life-History Evolution in Utah Chub (Gila atraria)
Preview not available

Abstract

We compared eight populations of Utah chub (Gila atraria), isolated since the late Pleistocene, to evaluate the relationship between predation by cutthroat trout (Oncorhynchus clarki) and chub life histories. Utah chub populations that have historically coexisted with cutthroat trout show higher juvenile growth rates, delayed age at maturity, larger size at maturity, and lower female reproductive effort than isolated populations with no predators. These results are consistent with life-history models of size-selective predation, in which juvenile mortality is high relative to adult mortality. We evaluated temperature differences, resource availability, and phylogenetic history as alternatives to the predation hypothesis. We conclude that life-history divergence among Utah chub populations is best explained by differences in predator-mediated mortality. This study is the first to evaluate effects of predation on life-history evolution in a long-lived prey species.

Page Thumbnails

  • Thumbnail: Page 
[948]
    [948]
  • Thumbnail: Page 
949
    949
  • Thumbnail: Page 
950
    950
  • Thumbnail: Page 
951
    951
  • Thumbnail: Page 
952
    952
  • Thumbnail: Page 
953
    953
  • Thumbnail: Page 
954
    954
  • Thumbnail: Page 
955
    955
  • Thumbnail: Page 
956
    956
  • Thumbnail: Page 
957
    957