![]() ![]() Robert Fitz-Roy, captain of the HMS Beagle, remarked that the large number of empty tortoise shells lying about the settlement showed “what havoc has been made among these helpless animals” ( 4). When Charles Darwin visited the island of Floreana in 1835, he learned that giant tortoises were the staple food source of the recent settlers to the island and that, as a consequence, their numbers had become “greatly reduced” ( 3). phantastica), and Rabida ( Geochelone sp. Fifteen formally described taxa of giant Galápagos tortoises are generally recognized, four of which are extinct from the islands of Floreana ( G. The giant tortoises of the Galápagos archipelago ( Geochelone spp.) are renowned both for their uniqueness and for their contribution to the development of Darwin's theory of natural selection ( 1). With enough individuals to commence a serious captive breeding program, this finding may help reestablish a species that was thought to have gone extinct more than a century ago and illustrates the power of long-term genetic analysis and the critical role of museum specimens in conservation biology. elephantopus has not been completely extinguished and still exists in an intermixed population on Isabela. Thus, we show that the genetic line of G. Surprisingly, we found that these “non-native” tortoises from Isabela are of recent Floreana ancestry and closely match the genetic data provided by the museum specimens. It was demonstrated that some living individuals on the nearby island of Isabela are genetically distinct from the rest of the island's inhabitants. Here, we use mitochondrial DNA and microsatellite data obtained from museum specimens to show that the population on Floreana was evolutionarily distinct from all other Galápagos tortoise populations. The application of modern DNA techniques to museum specimens combined with long-term study of a system creates new opportunities for identifying the living remnants of extinct taxa in the wild. This species was believed to have been exterminated within 15 years of Darwin's historic visit to the Galápagos in 1835. elephantopus, which once was endemic to the island of Floreana. Charles Darwin himself detailed the intense harvesting of one species, G. ![]() Because of heavy human exploitation, 4 of the 15 known species ( Geochelone spp.) have disappeared. Giant tortoises, a prominent symbol of the Galápagos archipelago, illustrate the influence of geological history and natural selection on the diversification of organisms. ![]()
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