The cause is helped by the fact that George is at the peak of his sexual powers.
He has two female companions of a closely related sub-species and it is hoped one of them will prove fertile.
Galapagos tortoises were among the species Charles Darwin observed to formulate his theory of evolution in the 19th century.

Scientist have been trying to get George to mate since 1993, when they introduced two female tortoises of a different subspecies into his pen.

The Galapagos National Park said the five eggs found earlier this week were 'in perfect condition' and have been placed in an incubator.

'Now we have to wait for the incubation period of 120 days to find out whether they are fertile,' it said in a statement.
Last year, 198lb (90kg) George stunned conservationists by mating for the first time in the 36 years he has been in captivity. However the eggs laid by one of his female companions turned out to be infertile.
Last year 13 eggs were laid. This year there are just five eggs.

Tortoises were hunted for their meat by sailors and fishermen to the point of extinction, while their habitat has been eaten away by goats introduced from the mainland