Still No Kids for Lonesome George

Lonesome George, estimated to be between 75-90 years old, is carrying a heavy responsibility on his back.  He is a Galapagos tortoise, believed to be the last living member of the Geochelone nigra abigdoni subspecies.  Lonesome George was found on Pinta island in 1972 and moved that year to a breeding center on Santa Cruz island, where he has lived ever since.

[googlemaps http://maps.google.com/maps?f=q&hl=en&q=Galapagos+Islands&sll=37.230328,-95.712891&sspn=32.470292,79.101563&ie=UTF8&cd=1&geocode=FZtw8_8dafmR-g&s=AARTsJpIMuB48zupNjG7pW0XO6lTJIzYPg&ll=-3.337954,-75.410156&spn=34.562146,87.890625&z=3&iwloc=addr&output=embed&w=500&h=200]

Hopes were high when the two females that have been Lonesome George's companions since 1993, finally laid eggs after 36 years of trying. They belong to the Geochelone becki subspecies of giant tortoise, believed to be the closest existing phenotype to that of Lonesome George. Between them, the females laid 13 eggs on Santa Cruz island in July. It seemed as if Lonesome George was finally going to become a father, providing for the continuity of his species.

The eggs were placed in an artificial incubator, but hope began to fade after it was reported that the eggs were losing weight and were not looking good. After 130 days of intensive care, conservationists came to the conclusion that all of the eggs were infertile. Galapagos National Park Director-General Sixto Naranjo says there are several possible explanations for why the eggs never developed embryos:

• Lonesome George is sterile


• The females are not from his subspecies
  


• The females’ 15 years without laying eggs rendered their first batch of eggs deficient
  


• The females' poor adjustment to captivity left them completely infertile.
  


• The diet in their breeding center negatively affected their reproductive systems.

[youtube=http://www.youtube.com/watch?v=pnv8KSjH0gU]

However the conservationists haven't given up just yet. A team of seven foreign biologists and 26 park rangers have begun taking blood samples from tortoises on nearby Isabela island in search of hybrid species that share as many or more genes with Lonesome George, Yale biologist and giant tortoise specialist Gisella Caccone said in a news release. Even at 90-years-old, Lonesome George is relatively young and may still have many years of sexual activity ahead.

Below is a short documentary by Sir David Attenborough on the history of Lonesome George:

[youtube=http://www.youtube.com/watch?v=32ed-bDAypg&feature=related]