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.

Inbreeding and Extinction: A Threshold Effect

Richard Frankham
Conservation Biology
Vol. 9, No. 4 (Aug., 1995), pp. 792-799
Stable URL: http://www.jstor.org/stable/2386988
Page Count: 8
  • Download ($42.00)
  • Subscribe ($19.50)
  • Cite this Item
Inbreeding and Extinction: A Threshold Effect
Preview not available

Abstract

A fundamental assumption underlying the application of genetics within conservation biology is that inbreeding increases the risk of extinction. However, there is no information on the shape of the relationship, the available evidence has not distinguished genetic and nongenetic effects, and the issue is controversial. Methods were devised to separate genetic and nongenetic causes causes of extinction in inbred populations, and they were used to analyze data from Drosophila melanogaster, D. virilis, and Mus musculus. Inbreeding markedly increased rates of extinction in all cases. All showed a threshold relationship between incremental extinction and inbreeding with low initial extinction, but they showed notably increased extinction beginning at intermediate levels of inbreeding. There was no difference in extinction levels at similar inbreeding coefficients in populations inbred at different rates (full sibling versus double first cousin). Endangered species may give little warning of impending extinction crises due to inbreeding.

Page Thumbnails

  • Thumbnail: Page 
792
    792
  • Thumbnail: Page 
793
    793
  • Thumbnail: Page 
794
    794
  • Thumbnail: Page 
795
    795
  • Thumbnail: Page 
796
    796
  • Thumbnail: Page 
797
    797
  • Thumbnail: Page 
798
    798
  • Thumbnail: Page 
799
    799