It's the reptilian feel-good story of the year: A species of giant tortoise thought to be extinct for 150 years turns out to be alive and living on an even more remote island than the one from which it supposedly died out. Scientists found evidence of the species known as Chelonoidis elephantopus living on the north shore of Isabela Island, in the Galapagos archipelago. The permanent loss implied by the word "extinct" always makes stories about the end of species so depressing. And it's the reversal of that permanence that imbues the rare story of an extinct species bouncing back with such triumph. In this case, scientists came on their happy discovery by genetic detective work: According to a story in Current Biology, their analysis of hybrid animals shows enough genetic material from the species thought to be extinct that it shows a parent must be alive. A Yale team had thought it could reproduce the species by breeding the hybrids together for many generations, but the discovery that the parents were alive means that won't be necessary. Now they just have to find one.