Lonesome males of the Galapagos

Celebrity is not usually associated with middle-aged giant tortoises from the Galapagos Islands, but then few have been so influenced by humanity's whims as Lonesome George and Pepe. They have no choice but to live out their lives lumbering torhythms set by invaders from the outside world.

To George fame came in 1971. He was discovered on the tiny uninhabited island of Pinta, the last surviving member of his sub-species. Now he lives under the scrutiny of scientists who hope against hope that he will pass on his genes to a new generation.

Pepe is unique in another sense, the last domesticated tortoise on the Galapagos, which teemed with the pets until conservationists impounded his contemporaries. The tourism boom finally fenced him in.

Three weeks ago the tanker Jessica ran aground near the islands, leaking almost 950,000 litres of oil. It was feared that the islands' many unique species would be damaged, but ecologists expect the archipelago to make a full recovery.

Pirates and whalers began the onslaught on tortoises when they realised that they made excellent fresh meat supplies on board their ships, because they can survive for six months without food and water.

But it was the goats introduced to the Galapagos by the early settlers that really did it for George's clan, destroying the ecological balance on the islands, 600 miles from mainland Ecuador, where it evolved over millennia.

By the time George was discovered rearing programmes were replenishing the gene pool of other tortoise sub-species, but his case was different. Unless a mate could be found his group faced extinction.

George was taken to the Charles Darwin Research Centre on Santa Cruz island and provided with a harem from related sub-species, but he was just not interested. Thirty years later the last Geochelone elephantopus abingdoni is as lonesome as ever.

Pepe grew up on San Cristobal island in the 1920s, in an era when it was common to whip baby tortoises out of their natural habitat and take them home. In 1959 the Galapagos National Park was formed and park officials rounded up all the domesticated tortoises they could find. All, that is, except Pepe, who was by then in the charge of Franciscan missionaries, who were allowed to keep him.

Eventually he became the island's mascot, and he lumbered around freely until the early 90s, when tourism began to interfere with his routine.

Since then he has lived in a small enclosure, where younger visitors ride on his saddle-shaped back.