The thought of a wrinkled octogenarian trying to make babies is somewhat unsavoury — unless we are talking about Lonesome George, the Galápagos giant tortoise, the last of his kind and hence the world’s rarest living creature. Last month, one of two females with whom George shares his enclosure laid a clutch of eggs, triggering widespread speculation that George was about to become a dad.

Since 1971, when a snail biologist came unexpectedly face to face with this large male tortoise on the remote island of Pinta, in the north of the Galápagos archipelago, George has shown a remarkable talent for setting the news agenda. His discovery sent ripples of excitement around the Pacific island group, which lies some 600 miles off the west coast of South America. Two centuries of culinary exploitation by pirates and whalers had taken their toll on all 15 Galápagos tortoise varieties, and those on Pinta — and a couple of other islands — had been assumed to be extinct.

George, the first tortoise seen on Pinta for more than 60 years, proved otherwise. In March 1972, wardens from the Galápagos National Park shipped him to the central island of Santa Cruz, where he has remained ever since at the Charles Darwin Research Station, waiting for some bright scientist to find a way to coax his special set of genes into the next generation.

George does not have the most encouraging of reproductive records. In the early 1990s, after almost two decades in solitary confinement, he was given a new enclosure and some company in the shape of “Female No 106” and “Female No 107”. These tortoises had been sourced from Wolf volcano on Isabela, the closest island to Pinta, the idea being that hybrid hatchlings would be better than no hatchlings at all — although, given that George may live to be 200, there was no point in rushing things. To the frustration of his matchmakers, though, George had something more important to do than procreate. He was busy building a brand.

For the next decade, George stubbornly avoided sex. He was even able to contain his arousal when, in 1993, a dedicated Swiss zoologist who became known as “Lonesome George’s girlfriend” gave him manual manipulation every day for four months. But, as a conservation icon, he did win the affections of a growing number of tourists. "Whatever happens to this single animal, let him always remind us that the fate of all living things on Earth is in human hands,” declared the information panels around his enclosure.

The downside to George’s fame became apparent in 1995, when he began to receive death threats. A handful of sea cucumber fishermen, unhappy with quotas imposed on their activities by conservationists, stormed into the research station and threatened to kill the reptilian poster boy unless restrictions were lifted. After tense negotiations, they were allowed to return to their boats. The sea cucumbers were the losers but George was safe.

The celibate recluse was now the most famous resident of Galápagos, his name appearing with impressive regularity alongside that of the archipelago’s best-known visitor, Charles Darwin.

In 2003 it was announced that George’s native island was at last free of goats, which compete with giant tortoises for the vegetation on which both creatures feed. More than 40,000 of the destructive goats, descended from a pair released on Pinta in the 1950s, had been shot by wardens in the 1970s and, now that they had been eliminated, it was hoped that tortoises from a different island might be introduced as ecological stand-ins for Lonesome George’s long-dead ancestors. There was talk of allowing George to join them for the rest of his days. But in May 2007, an announcement from geneticists at Yale University in the US put the move on hold.

George, they revealed, was not entirely alone among Galápagos tortoises. While analysing blood samples taken from a few tortoises on Wolf Volcano, on Isabela, several years earlier, they had found DNA from one male whose father appeared to have been a Pinta tortoise. That male may still be out there on Wolf's steep slopes — a “brother” for George, if you like.

In December last year, the geneticists went to collect blood from more Wolf volcano tortoises. If some samples turn out to have come from tortoises with Pinta genes, a further expedition will be mounted to find the reptiles themselves, which could then be shipped to Santa Cruz in the hope that they can hit it off with George and create a population of Pinta-like tortoises.

The geneticists initially sampled just 27 tortoises on Wolf volcano and found one with Pinta ancestry. The recent expedition has given them 1,663 tortoises to assess, so there is a good chance of finding more.

Meanwhile, there has been great interest in the eggs laid in George’s enclosure. Last year, both Female No 106 and Female No 107 built nests for the first time and furnished them with 20 eggs. But none of them hatched and, when the Yale geneticists combed the rotting eggs for signs of George’s DNA, they found none. So even if he did mate with the females (which nobody can confirm), it remains uncertain whether he is ready or even able to be a father.

But this year is rather special for Galápagos and George may be orchestrating a publicity stunt to suit the occasion. Last month, when a warden found the clutch of five eggs in his enclosure, both the Galápagos National Park (which officially owns him) and the Charles Darwin Foundation (which houses him) celebrated their 50th anniversaries. If, by some miracle, the eggs turn out to be fertile, they would hatch in mid-November, just as the world celebrates the 150th anniversary of the publication of Darwin’s On the Origin of Species.

Henry Nicholls is the editor of Galápagos News and the author of Lonesome George: The Life and Loves of a Conservation Icon.

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