This water snail is being closely watched as part of a study that hopes the pond-dwelling gastropod will hold the key to counteracting the effects of senility in humans. Scientists at the University of Brighton have found that snails suffer similar memory loss to humans as they get older. Richard Faragher, professor of biological gerontology, said: "The poor animals get forgetful - there are such things as senile snails. One of the things you have to remember if you are a snail or, indeed, a person, is where you have left your food. As these little chaps get older, they forget where their lettuce is. I think all humans have been there and can sympathise with them." He added: "By understanding how the snail's brain changes, we can understand how to make it work normally and, by analogy, we can do the same with humans."