I’m amazed at the number of people who heard this snail story on radio 4 a few days ago. It was about a piece of fascinating research into the distribution of Cepaea nemoralis – the brown lipped banded snails - which has been a food source in the Eastern Pyrenees for thousands of years. They are pretty little snails which come in a variety of colours and can be kept as pets.(http://petsnails.proboards.com/thread/11040) This one has a lot of stripes but the number of stripes varies and I also have yellow ones in my garden. (Note: the snail pictured is Cepaea hortensis - they mainly differ by the colour of their lip) The experiment involved looking closely at their mitochondria – those energy generators of every cell. The results suggest that a human population in Mesolithic times migrated from the Pyrenees to Ireland and took their favourite food with them. In a wave of colonisation 8,000 years ago it seems Cepaea wasn’t the only thing the people took with them because they also seem to have transported the strawberry tree, the Kerry slug, and the Pyrenean glass snail. They’ve even worked out how they were transported from the Pyrenees down the river Garonne and across the sea - amazing!
Migrant people have taken edible snails all over the world with them as they travelled.
(Grindon AJ, Davison A (2013) Irish Cepaea nemoralis Land Snails Have a Cryptic Franco-Iberian Origin That Is Most Easily Explained by the Movements of Mesolithic Humans. PLoS ONE 8(6): e65792. doi:10.1371/journal.pone.0065792)