It was further established that there was another male in San Diego Zoo, and he was transferred to the Galapagos colony. Since 1965 the two males and twelve females from this island have been taken to the research station as breeding stock. From lichen growths on the backs of the females it was clear that they had not mated for several seasons, probably because they had had to scatter so far in search of food. There were only 14 of the Espanola form, Geochelone elephantopus hoodensis. Of those that were not extinct, several populations were precariously small. By that time, five tortoises races had been declared extinct, among them the Pinta Island form. The Charles Darwin Research Station was opened on Santa Cruz Island in 1962 with the objective of protecting the remaining animals. Pigs gone wild scoffed tortoise eggs, dogs killed juveniles, escaped goats and donkeys devoured the vegetation. Whalers, merchantmen and naval vessels took thousands on board as an insurance against scurvy, because the tortoises could live for up to 18 months without food or water. This observation formed part of his world-changing Theory of Evolution by Natural Selection.īefore Darwin’s arrival the giant tortoises were in trouble again. In wetter regions such as Santa Cruz Island and southern Isabela they retained their domed shells and grew much bigger.Ĭharles Darwin, visiting the islands in 1835, saw that the tortoises on each island were different although they had obviously descended from a common stock which was now extinct on the mainland. On arid, sparsely vegetated islands such as Pinta and Espanola only those with flared up shells and longer necks could reach the high-growing plants. They landed on 10 of the islands and have become adapted to the conditions of each. Then seeds carried by birds took root, the birds themselves stayed, and animals arriving on rafts of vegetation carried by ocean currents no longer perished.Īmong there animals were the giant tortoises. For centuries these volcanic wastelands were bare. Like other dinosaurs they began to die out when mammals evolved and they were neither clever enough nor fast enough to compete for food.īut three million years ago, the Galapagos Islands burst out of the Pacific Ocean. In the age of the dinosaurs they covered most of the Americas, Europe and Asia. Once there were millions of giant tortoises. And when he dies the Pinta tortoises will be extinct. It is a male known by his keepers as Lonesome George. There is only one Pinta Island tortoise ( Geochelone elephantopus abingdoni). The rarest animal in the world today is a giant tortoise which lives in the Galapagos Islands.
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