| Abingdon Island Tortoise | |
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| Lonesome George, a Galápagos Tortoise suspected to be the last surviving member of his subspecies | |
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| Subspecies: | G. n. abingdoni
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| Trinomial name | |
| Geochelone nigra abingdoni | |
Lonesome George (Spanish: Solitario Jorge) is the last known individual of the Pinta Island Tortoise (Geochelone nigra abingdoni) which is one of eleven extant subspecies of Galápagos tortoise, all of which are native to the Galápagos Islands.[1][2] He has been labelled the rarest creature in the world, and is a potent symbol for conservation efforts in the Galápagos and internationally.[3] It is thought that he was named after a character played by American actor George Gobel.
George was first seen on the island of Pinta on 1 December 1971 by American snail biologist Joseph Vagvolgyi. The island's vegetation had been decimated by introduced feral goats, and the indigenous G. n. abingdoni population had been reduced to a single individual. Relocated for his safety to the Charles Darwin Research Station, George was penned with two females of a different subspecies, but although eggs have been produced, none have hatched.
George is estimated to be 60–90 years of age, and is in good health.[4] 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.
The presence of mixed race Pinta ancestry tortoises around Wolf Volcano, on neighbouring Isabela island, suggests the recent presence of at least one Pinta individual near Wolf Volcano. A possible purebreed Pinta candidate, male and dubbed "Tony", lives in a Prague zoo.
There is a reward of $10,000 for the discovery of a Pinta female.[5]
Reproduction attempts
editAttempts at mating Lonesome George were unsuccessful for several decades, possibly due to the lack of a female of his own subspecies, and prompted researchers at the Darwin Station to offer a $10,000 reward for a suitable mate.[2] George is penned with two females of a different subspecies, Geochelone nigra becki from the Wolf Volcano region of Isabela island, in the hope that his genotype would be retained in the resulting progeny. This subspecies was thought to be genetically closest to George's; however any offspring successfully hatched from George and his consorts would be intergrades, not purebreds of the Pinta subspecies.[4] On July 21 2008, it was reported that George had unexpectedly mated with one of his female companions. A total of thirteen eggs were collected and placed in incubators.[6] However, on November 11 2008, The Charles Darwin Research Center reported that 80% of the eggs showed weight loss characteristic of being inviable.[6][7] To the disappointment of the Darwin Center, by December 2008 the remaining eggs had failed to hatch and x-rays showed them to be inviable.[8]
However, on 21 July 2009, exactly one year after first announcing George had mated, the Galapagos National Park announced that a second clutch of five eggs had been laid by one of George's female companions.[9] The park authority expressed its hope that the second clutch of eggs, which it described as being in perfect condition, might prove to be fertile. The eggs have been moved to an incubator. "Now we have to wait for the incubation period of 120 days to find out whether they are fertile", the Galapagos National Park has said.[10] On December 16, it was announced that the incubation period for the first 5 eggs had ended and the eggs were shown to unfortunately be inviable; also a second batch of 6 eggs laid after the first batch by the other female are looking like they might also end up being inviable. [11]
Possibility of another Pinta purebreed
editIn the wild
editIn May 2007, analysis of genomic microsatellites (DNA sequences) suggested that other individuals of Geochelone nigra abingdoni may still exist in the wild at the Galápagos.[12] Researchers have identified one male tortoise from the Volcano Wolf region of neighboring Galápagos island of Isabela which has half his genes in common with George's subspecies. This animal must be a first generation intergrade between the subspecies of the islands Isabela and Pinta.[12] It is possible that a pure Pinta tortoise lives among the 2,000 tortoises on Isabela.[13]
| “ | "The identification of eight individuals of mixed ancestry among only 27 individuals sampled (estimated Volcano Wolf population size 1,000–2,000) ... suggests the need to mount an immediate and comprehensive survey ... to search for additional individuals of Pinta ancestry."[12] | ” |
At Prague Zoo
editAnother male tortoise by the name of Tony, who currently resides in a Prague zoo, has recently been discovered as most likely being an additional pure breed, native, Pinta tortoise. Believed to be born around 1960, Tony has been housed in the zoo since 1972. Peter Pritchard, one of the world’s foremost authorities on Galápagos tortoises (and of tortoises and turtles of the world more generally), has found the shell on Tony to be extremely similar to that of George and Pinta museum specimens. Research is still currently being processed to confirm this match and Tony is still currently being held at the Prague zoo.[5]
References
edit- ^ Geochelone nigra, IUCN Red List
- ^ a b Gardner, Simon (February 6 2001), Lonesome George faces own Galapagos tortoise curse
{{citation}}: Check date values in:|date=(help) - ^ Nicholls, H (2006), Lonesome George: The Life and Loves of a Conservation Icon, London: Macmillan Science, ISBN 1-4039-4576-4
- ^ a b "Joy at giant tortoise eggs". BBC. 23 July 2008.
- ^ a b Sulloway, Frank J. (06-07-28). "Is Lonesome George Really Lonesome". Retrieved 22 December 2009.
{{cite web}}: Check date values in:|date=(help) - ^ a b "Dwindling Hopes of Offspring from Lonesome". Charles Darwin Foundation. Retrieved 11 November 2008.
- ^ "Galapagos bachelor tortoise struggles to be a dad". CBC. 11 November 2008.
- ^ "Lonesome George's first sex in decades ends in disappointment". The Telegraph. Retrieved 27 January 2009.
{{cite news}}: Italic or bold markup not allowed in:|publisher=(help) - ^ "New eggs spark Galapagos tortoise hopes". WA Today. 22 July 2009. Retrieved 2009-07-22.
{{cite news}}: Italic or bold markup not allowed in:|publisher=(help) - ^ "Lonesome George, the last Galápagos giant tortoise, may become a dad". The Guardian. 22 July 2009. Retrieved 2009-07-22.
{{cite news}}: Italic or bold markup not allowed in:|publisher=(help) - ^ "Eggs from Lonesome George's Companion are inviable, Once Again". GNP NEWS. 16 December 2009. Retrieved 2009-12-19.
{{cite news}}: Italic or bold markup not allowed in:|publisher=(help) - ^ a b c Russello, Michael A.; Beheregaray, Luciano B.; Gibbs, James P.; Fritts, Thomas; Havill, Nathan; Powell, Jeffrey R.; Caccone., Adalgisa (1 May 2007), "Lonesome George is not alone among Galápagos tortoises" (PDF), Current Biology, 17 (9): R317–R318, doi:10.1016/j.cub.2007.03.002
- ^ "Iconic tortoise George may not be last of his kind". 2007-05-01. Retrieved 2007-10-20.
External links
edit- Charles Darwin Research Station Fact Sheet - Pinta giant tortoise (Geochelone abingdoni)
- Naked Scientists audio discussion of Lonesome George
- Article on Lonesome George The Giant Tortoise of Galapagos Island.
- Lonesome George, by Vicki Seal
- GC News: Team of Veterinarians Prepare Hybrid Tortoises for Release on Pinta Island in 2010
Category:Endemic fauna of the Galápagos Islands Category:Famous tortoises