Tortoise Thought to Be Extinct Rediscovered    [20-01-2012] Researchers were happy to discover that a species of giant tortoise may continue to live and thrive. The species ‘Chelonoidis elephantopus’ was previously thought to be extinct, but a small population may be living on the Galapagos Islands. Experts predict that a large number of this species inhabits Volcano Wolf on Isabela Island. A team from Yale University led the study. The researchers do not have physical proof that the tortoise is not extinct. This is because they did not find any living specimens of Chelonoidis elephantopus, which are thought to be native to the island of Floreana. What the researchers did find were giant tortoise hybrids with genetic make-up that shows they are linked to the purebred elephantopus. Hybrid species are made when one species mates with another to make a mixed breed. They are actually the first generation offspring of the rare reptile. Their genes showed that some of the hybrids had elephantopus mothers, while others had a father of the same species. The discovered hybrids were around 15 years old, so it is likely that their parents may still be alive on Isabela Island. In 2008, another Yale team took genetic data from the Floreana tortoises to restore the species. They were endangered and an extensive breeding program had been planned. The goal was to breed out the non-Floreana genes from the hybrid tortoises, if they were found. However, the new data shows that the effort may be unnecessary if living purebreeds can be found on the islands.     출처: 어린이 영자신문 키즈타임즈 (www.kidstimes.net)