Although scientists have believed snails are far too simple to be able to find their way home, Ruth Brooks, a 69-year-old grandmother, began an experiment to settle the question after she became exasperated with the snails in the garden of her home in Totnes, Devon, The Daily Telegraph reported Wednesday.
The snails had eaten her lettuce, ravaged her petunias and devastated her beans, Brooks said.
"I really don't like killing snails with pellets or salt and I wanted to find a humane way of protecting my garden," she said.
To find out whether snails have a homing instinct, Brooks gathered up the creatures in her garden and marked them with a particular colored nail polish. She asked her neighbors to do the same.
Then the snails were swapped around and Brooks made detailed notes of their movements.
Snails have a strong homing distance over 30 feet, she found, and some snails returned to their home garden from a distance of 300 feet.
David Hodgson, an ecology lecturer Exeter University who assisted with the experiment, said the findings were "amazing."
"The conventional thinking is that snails are far too simple to be able to find their way home," he said. "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."