 Subspecies were described from three other islands , but their existence is based on scant evidence . The purported <unk> Island subspecies ( C. n. <unk> ) was described from a single specimen collected by the California Academy of Sciences in December 1905 , which has since been lost . This individual was probably an artificial introduction from another island that was originally penned on <unk> next to a good anchorage , as no contemporary whaling or sealing logs mention removing tortoises from this island . The C. n. <unk> subspecies from Fernandina is known from a single specimen — an old male from the voyage of 1905 @-@ 06 . No other tortoises or remains have been found on the island , suggesting the specimen was an artificial introduction from elsewhere . Fernandina has neither human settlements nor feral mammals , so if this subspecies ever did exist , its extinction must have been by natural means , such as volcanic activity . The Santa Fe subspecies has no binomial name , having been described from the limited evidence of bone fragments ( but no shells , the most durable part ) of 14 individuals , old eggs , and old dung found on the island in 1905 @-@ 06 . The island has never been inhabited by man nor had any introduced predators . The remains are considered artificial introductions , possibly from camping at the good anchorage on the island . 
