- guardian.co.uk, Monday 2 July 2007 18.45 BST
The giant Galapagos tortoise known as Lonesome George. Photograph: Bob Strong/Reuters
Lonesome George, the last known survivor of a species of giant Galapagos tortoise and one of the world's most famous bachelors, may be about to receive the new, more unkind nickname of Hopeless George.
Scientists who have studied him say he appears to be impotent, or at least to have no interest in sex, so that even if a mate were found he probably would not rise to the occasion.
"George may be physiologically incapable of reproducing," Linda Cayot, a science adviser for the Galapagos Conservancy and former keeper of George, told the Reuters news agency.
The conservation icon, who weighs 90kgs, was until recently assumed to be the last member of a species of giant tortoise found on Pinta, one of the Galapagos islands off Ecuador's Pacific coast.
Earlier this year however researchers from Connecticut's Yale University said they had found a male tortoise on the island of Isabela, another Galapagos island, which was the offspring of a Pinta male and an Isabela female. That raised hopes of a suitable female being found for George.
But Ms Cayot poured cold water on the notion that he would become a father if only he had a mate. "The search is a long shot," she said. George ignored females from a different species who have shared his pen at the Darwin Research Centre. Even when younger, virile males were introduced, he showed no interest in emulating them.
"He has problems," said Sveva Grigioni, a Swiss biologist who worked with the tortoise 13 years ago. "He probably never saw a female and male of his own species reproducing."
Dr Grigioni said she could normally get tortoises to ejaculate within minutes, but she spent months manually stimulating George and never extracted semen from him.
Discovered in 1971 and estimated to be aged between 60 and 90, George is in his prime. In theory he should be able to live to 200 and still reproduce.
