The lightly coloured variety of snails found on the Isle of Wight.
A UNIQUE colony of snails has been discovered thriving in salty conditions on the Island.
The large colony live among maritime plants and chalk rubble in a very small and rare micro-environment on the Island’s south coast, exposed to sea spray, which would cause the common garden snail to shrivel up.
Peter Cosier, an amateur naturalist, said: “I believe these snails have evolved as a distinct sub-species to live in this very hostile salt-laden micro-environment, where the white shells and pale bodies camouflage them from predators.
“If this is the case, it is a splendid example of Darwin’s theories, perhaps even equal to examples on the Galapa-gos Islands.
“I can find no account of this attractive and dramatic form of snail being recorded before and believe it could be quite unique to the Isle of Wight.”
The snails have been identified by the Natural History Museum, London, as a form of the common garden snail (helix aspersa) and Mr Cosier has searched the chalk downland for similar snails near his home in Kent.
“I thought the thicker shells of the Isle of Wight snails might be the result of a calcium-rich diet. I have found no examples here of the thicker shells, let alone the colour change.”
Dr Colin Pope, Isle of Wight Council senior ecology officer, said: “It is fitting that Mr Cosier, on the 200th anniversary of Darwin’s birth, should have discovered a snail that so wonderfully demonstrates Darwin’s theory of evolution.
“It is not uncommon for creatures to adapt to the environment they inhabit.
“The snails with a pale appearance blend with their surroundings and are more likely to be camouflaged from predators and hence survive to pass on their characteristics to the next generation.
“This theory is described by Charles Darwin in his book Origin of Species, which he began writing during a visit to the Isle of Wight in 1858.”
Reporter: martinn@iwcpmail.co.uk