A grandmother has been crowned Britain’s amateur scientist of the year after proving that snails have an internal – HOMING instinct.
Keen gardener Ruth Brooks has shown that they have their own ‘Sat Nav’ – which overturns previous scientific belief – that the gastropods simply follow a snail trail.
Experts have always thought that the primitive molluscs are too simple a life form to be able to return to the same spot or navigate.
But Ruth, 69, set about disproving the widely-held theory in an attempt to help gardeners rid their plots of the shelled-menace.
She was plagued by snails eating her vegetables and despite moving them to a nearby piece of waste land they always came back to attack her produce.
Ruth, of Totnes, Devon, then rounded up all her snails and marked them with a particular colour nail polish and asked neighbours to collect their little pests and do the same.
The snails were then swapped around and Ruth made detailed notes of their movements which showed most, if not all, returned to their original gardens.
Experts have labelled the findings ”amazing” and she has now been hailed Britain’s Amateur Scientist by the BBC Radio 4’s Material World programme in conjunction with Exeter University.
Ruth, a retired special needs tutor, said she has discovered the Helix aspera (corr) – the common garden snail – has a strong homing instinct up 30 metres away.
She said: ”I’ve always wanted to know whether the snails that decimate my plants just come back when I move them, and if they do, what is their homing distance?
”How far away would I have to move them so they won’t come back?
”I would say that on the evidence that it would be safe to take your snails away beyond a 100m or even further.
”Put them somewhere nice with some food and you can be almost certain that they won’t come back. I shall certainly be following that advice.”
Mother-of-one Ruth began her project earlier this year after she became fed up with snails which were attracted to her garden because of its heavy clay soil.
She said she spent hundreds of pounds trying to combat the problem without resorting to pellets because she worried they would harm soil, birds and wildlife.
Ruth didn’t want to kill the snails so she she took them away but found that they kept coming back.
Scientists originally thought the snail was too simple an organism to have a homing instinct however but her study has now proved the opposite is true.
Dr Dave Hodgson, a bioscientist from from Exeter University, was brought in to assist her with the experiment.
He admits that before before the experiment started he did not believe snails had a homing instinct.
He said: ”I am amazed, I was extremely sceptical. I thought there was no way that these creatures would show a homing instinct in the way that homing pigeons do for example. And yet they do.
”I am interested in taking the research further myself and have two theories I would like to explore
”They either have some clever mechanism that helps them get home or it’s entirely possible that snails are just moving around the landscape.
”Then when they stumble across a place they come from they just stop.”
Ms Brooks beat 1,000 other entries to become Britain’s best amateur scientist and her theory will be written and published in a major scientific journal.
* Helix aspersa, the common name garden snail, is a species of land snail, a pulmonate gastropod that is one of the best-known of all terrestrial molluscs.
The species is edible, but more often regarded as a garden pest. It is native to the Mediterranean region and western Europe, from northwest Africa and Iberia east to Asia Minor, and north to the British Isles.
The garden snail is a herbivore and hermaphrodite, producing both male and female gametes. Reproduction is usually sexual, although self-fertilisation can occur. During a mating session of several hours, two snails exchange sperm.
The garden snail uses love darts during mating. Females lay up to six batches of 80 eggs a year. Young snails take one to two years to reach maturity.