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The Pinta Island tortoise (''Chelonoidis nigra ''〔〔), also known as the Pinta giant tortoise, Abingdon Island tortoise, or Abingdon Island giant tortoise,〔 is a subspecies of Galápagos tortoise native to Ecuador's Pinta Island that is probably extinct. The subspecies was described by Albert Günther in 1877 after specimens arrived in London. By the end of the 19th century, most of the Pinta Island tortoises had been wiped out due to hunting. By the mid-20th century, the subspecies was assumed to be extinct until a single male was discovered on the island in 1971. Efforts were made to mate the male, named Lonesome George, with other subspecies, but no viable eggs were produced. Lonesome George died on 24 June 2012 and the subspecies was believed to have become extinct with his death. However, 17 first-generation hybrids have been found at Wolf Volcano on Isabela Island during a recent trip by Yale University researchers. As these specimens are juveniles, their parents may still be alive.〔(【引用サイトリンク】url=http://www.livescience.com/24806-galapagos-tortoise-lonesome-george.html )〕 Background Information "Lonesome George" along with other of the tortoises on Pinta Island, belong to a genus of 21 species. Giant tortoises were widespread on most of the continents except for Australia and Antarctica. Not only do the Galapagos tortoises remain the largest living tortoises, but in the Galapagos, distinct populations survived in multiple localities. Several of the surviving subspecies of Galapagos tortoises are seriously endangered. Lonesome George would be the perfect example. It is said that the decline of the population began in the 17th century, due to buccaneers and whalers. They hunted tortoises as a source of fresh meat, and took away about 200,000 tortoises collectively. An interesting fact is that these animals can survive up to six months without any food or water. During their time on the island, the Galapagos Tortoise, including the Pinta Island subspecies, was observed many times and was it was concluded that the tortoises rest about 16 hours a day. The Galapagos tortoises are herbivores who feed primarily on greens, grasses, native fruit, and cactus pads. These tortoises also drink heavy quantities of water which they can then store in their bodies for long periods of time and utilize them for later use. For breeding, the tortoises are most active during the ‘hot season’ (January to May) and then during the cool season (June to November), female tortoises migrate to nesting zones in order to lay out their offspring. Natural Selection The origin and systematic relationships are still unresolved today, it even captivated Charles Darwin himself. Scientists used DNA sequencing and decided to collect a few tortoises from the Pinta Island in 1906. With DNA sequencing as their method, their results show that the three best candidates for the closest living relative of the Galapagos tortoises are all located in South America. It is the yellow-footed tortoise (Geochelone denticulata), the red-footed tortoise (Geochelone Carbonara), and the chaco tortoise (Geochelone Chilensis). These 3 species are known as extant species. ==Subspecies naming== This subspecies was originally described in 1877 by German-born British herpetologist Albert Günther, who named it ''Testudo abingdonii'', a new species, in his book ''The Gigantic Land-tortoises (Living and Extinct) in the Collection of the British Museum''. The name, ''abingdonii'', derives from Abingdon Island, now more commonly known as Pinta Island. The knowledge of its existence was derived from short statements of the voyages of Captain James Colnett in 1798 and Basil Hall in 1822.〔 In 1876 Commander William Cookson brought three male specimens (along with other subspecies of Galápagos tortoise) to London aboard the Royal Navy ship HMS ''Peterel''.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pinta Island tortoise」の詳細全文を読む スポンサード リンク
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