Giant Tortoise Thought Extinct Is Likely Still Alive, Yale Study Says

A giant tortoise thought to have been hunted to extinction more than 150 years ago — and whose distinctive saddle-shaped shell helped inspire Charles Darwin’s theory of natural selection — may still be living in the Galápagos Islands, according to a new Yale University study. Using blood samples collected from tortoises currently living on Isabela Island, the largest of the Galápagos islands, researchers found in 84 animals the genetic signature of the missing Chelonoidis elephantopus. Researchers say this suggests that one of these hybrid tortoises’ parents were purebred members of the missing species, which had lived on the nearby island of Floreana until their numbers were decimated through hunting by whalers and settlers. Since many of the tortoises tested were likely younger than 15 years old, researchers say there is a high probability that some of their purebred parents, which can have a lifespan of more than 100 years, are still alive. “If we can find these individuals, we can restore them to their island of origin,” said Gisella Caccone, a senior Yale researcher and lead author of the study, published in the journal Current Biology.