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.

Local Adaptation in Two Subspecies of an Annual Plant: Implications for Migration and Gene Flow

Eric S. Nagy and Kevin J. Rice
Evolution
Vol. 51, No. 4 (Aug., 1997), pp. 1079-1089
DOI: 10.2307/2411037
Stable URL: http://www.jstor.org/stable/2411037
Page Count: 11
  • Read Online (Free)
  • Download ($4.00)
  • 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.
Local Adaptation in Two Subspecies of an Annual Plant: Implications for Migration and Gene Flow
Preview not available

Abstract

Plant populations often adapt to local environmental conditions. Here we demonstrate local adaptation in two subspecies of the California native annual Gilia capitata using standard reciprocal transplant techniques in two sites (coastal and inland) over three consecutive years. Subspecies performance in each site was measured in four ways: probability of seedling emergence, early vegetative size (length of longest leaf), probability of flowering, and total number of inflorescences produced per plant. Analysis of three of the four variables demonstrated local adaptation through site-by-subspecies interactions in which natives outperformed immigrants. The disparity between natives and immigrants in their probability of emergence and probability of flowering was greater at the coastal site than at the inland site. Treated in isolation, these two fitness components suggest that migration from the coast to the inland site may be less restricted by selection than migration in the opposite direction. Two measurements of individual size (leaf length and number of inflorescences), suggest (though not strongly) that immigrants may be subject to weaker selection at the coastal site than at the inland site. A standard cohort life table is used to compare replacement rates (R0) for each subspecies at each site. Comparisons of R0s suggest that immigrants are under a severe demographic disadvantage at the coastal site, but only a small disadvantage at the inland site. The results point out the importance of integrating over several fitness components when documenting the magnitude of local adaptation.

Page Thumbnails

  • Thumbnail: Page 
1079
    1079
  • Thumbnail: Page 
1080
    1080
  • Thumbnail: Page 
1081
    1081
  • Thumbnail: Page 
1082
    1082
  • Thumbnail: Page 
1083
    1083
  • Thumbnail: Page 
1084
    1084
  • Thumbnail: Page 
1085
    1085
  • Thumbnail: Page 
1086
    1086
  • Thumbnail: Page 
1087
    1087
  • Thumbnail: Page 
1088
    1088
  • Thumbnail: Page 
1089
    1089