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.

Quaternary Refugia in Tropical America: Evidence from Race Formation in Heliconius Butterflies

K. S. Brown, P. M. Sheppard and J. R. G. Turner
Proceedings of the Royal Society of London. Series B, Biological Sciences
Vol. 187, No. 1088 (Nov. 5, 1974), pp. 369-378
Published by: Royal Society
Stable URL: http://www.jstor.org/stable/76410
Page Count: 10
  • Read Online (Free)
  • 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.
Quaternary Refugia in Tropical America: Evidence from Race Formation in Heliconius Butterflies
Preview not available

Abstract

The hypothesis of Haffer, Turner, and others, that patterns of race and species formation in the tropical forests of South America are the result of the isolation of populations in forest refugia during widespread climatic changes in the geologically recent past, is supported by the distribution of races in the butterfly genus Heliconius: the location of the refuges for these butterflies shows an excellent accord with the refuges deduced by Haffer in his studies of forest birds. The strict parallel variation through most of South America of the various races of H. melpomene, H. erato and of ten similarly-patterned species shows the result of selection for Mullerian mimicry; as the patterns must be subject to strong stabilizing selection, and as the low vagility of the butterflies normally produces isolation by distance even in a continuous population, it is suggested that the extreme divergence of pattern that some (but not all) Heliconius underwent in the forest refugia results from selection pressure in favour of mimicking the most abundant or distasteful local species, which would vary from refuge to refuge, rather than from geographical isolation per se.

Page Thumbnails

  • Thumbnail: Page 
369
    369
  • Thumbnail: Page 
370
    370
  • Thumbnail: Page 
371
    371
  • Thumbnail: Page 
372
    372
  • Thumbnail: Page 
373
    373
  • Thumbnail: Page 
374
    374
  • Thumbnail: Page 
375
    375
  • Thumbnail: Page 
376
    376
  • Thumbnail: Page 
377
    377
  • Thumbnail: Page 
378
    378