Lonesome George is the name given to this tortoise in the Charles Darwin Research Centre. It is believed to be the last surviving individual of a purebred Pinta Island tortoise so when he dies the sub-species will be extinct.
George was first seen on the island of Pinta in December 1971 The island's vegetation had been devastated by introduced feral goats, and the indigenous sub-species of giant tortoise population had been reduced to a single individual. Relocated for his safety to the Charles Darwin Research Station, George has been penned with two genetically similar females of a different subspecies, and although eggs have been produced, none have hatched. George is estimated to be about 100 years of age, and he is in good health. A prolonged effort to exterminate goats introduced to Pinta is now complete, and the vegetation of the island is starting to return to its former state but there are no tortoises to re-introduce.
Additional note - Lonesome George died on 24th June 2012 so the species is now extinct.