Biochemical relationships of the Galápagos Giant tortoises (Geochelone elephantopus)

Authors

  • Ronald William Marlow,

    1. Museum of Vertebrate Zoology, University of California, Berkeley, California 94720, U. S. A.
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    • **Division of Biological Sciences, University of Michigan, Ann Arbor, Michigan 48 109, U.S.A.

  • James L. Patton

    1. Museum of Vertebrate Zoology, University of California, Berkeley, California 94720, U. S. A.
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  • *Contribution No. 307 from the Charles Darwin Foundation for the Galapagos Isles.

Abstract

Genetic relatedness was estimated among seven of the extant races of Giant tortoises (Geochelone elephantopus), of the Galapagos Archipelago and between these forms and mainland South American taxa, by starch gel electrophoresis. Genetic similarity among the island races is unrelated to carapace shape, suggesting that the latter was independently derived several times on separate islands. The Galapagos species shares no greater similarity with any mainland species than the latter do among themselves. Thus, the most direct common ancestor of the Galapagos forms is undoubtedly extinct.

Ancillary