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.

Major Genetic Differences between Crown-of-Thorns Starfish (Acanthaster planci) Populations in the Indian and Pacific Oceans

John A. H. Benzie
Evolution
Vol. 53, No. 6 (Dec., 1999), pp. 1782-1795
DOI: 10.2307/2640440
Stable URL: http://www.jstor.org/stable/2640440
Page Count: 14
  • 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.
Preview not available

Abstract

Spatial variation in allelic frequencies at nine allozyme loci were assayed in 20 populations of the crown-of-thorns starfish, Acanthaster planci, collected throughout the Pacific and Indian Oceans. These data were analyzed together with published data, for the same loci, from an additional 19 populations, giving a total sample size of approximately 1800 individuals. There was a marked discontinuity between the Indian and Pacific Ocean populations, but those off Western Australia and from the Southeast Asian region had a strong Pacific affinity. The genetic groups were congruent with the distributions of two color morph groups: gray-green to red-brown forms in the Pacific and a blue to pale red form in the Indian Ocean. These patterns of genetic structure are similar to those described for the starfish Linckia laevigata, which has similar life-history characteristics. Vicariant events may have influenced some populations within the Pacific, but the allozyme data cannot resolve the effects of these events clearly. Patterns of variation within regions were consistent with isolation by distance, but, at larger scales, were obscured by regional vicariance and some outliers, particularly by apparently high levels of gene flow between Japan and the Great Barrier Reef, Australia. Apparent gene flow between population pairs was not closely related to present-day ocean currents. The results demonstrate a strong influence of allopatric separation on genetic divergence at large geographic scales, but also show evidence of slow rates of change in gene frequencies consistent with the large population sizes of this species. Low levels of divergence between groups demonstrate the genetic structure is recent (Pleistocene) and are likely responses to changes in climate and sea level.

Page Thumbnails

  • Thumbnail: Page 
1782
    1782
  • Thumbnail: Page 
1783
    1783
  • Thumbnail: Page 
1784
    1784
  • Thumbnail: Page 
1785
    1785
  • Thumbnail: Page 
1786
    1786
  • Thumbnail: Page 
1787
    1787
  • Thumbnail: Page 
1788
    1788
  • Thumbnail: Page 
1789
    1789
  • Thumbnail: Page 
1790
    1790
  • Thumbnail: Page 
1791
    1791
  • Thumbnail: Page 
1792
    1792
  • Thumbnail: Page 
1793
    1793
  • Thumbnail: Page 
1794
    1794
  • Thumbnail: Page 
1795
    1795