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Pyrenean glass snails - human migration

Tracking Human Migrations through … snails

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How is it possible for snails in Ireland to be genetically the same as snails in France? Well probably they didn’t travel thousands of miles including sea on their own. Scientists believe that this happened due to a human migration going back 8000 years.

The similarity of the genetic material, in addition to the fact that those snails cannot be found in Britain, suggests that their location is related to human migration.  A research paper published on PLOS ONE by Adele J. Grindon and Angus Davinson explains in detail why this is possible.

Pyrenean glass snails are not the only species found in Ireland in an unexplained way. It also includes a strawberry tree and the Kerry slug. The samples that were collected were from France, Spain and Italy as well as the west coast of Ireland. DNA was extracted from the samples and compared to each other showing the similarities in the genetic material of all samples.

And while Britain is the main origin of the Irish fauna, in this case this doesn’t apply. The explanation that someone would give is that snails migrated from the Pyrenees mountains to France and then to Britain and then to Italy. However the problem with this theory is that traces of the specific genetic material cannot be found in Britain.

Therefore, Davinson suggests that the evidence shows the possibility that Ireland was colonized earlier than Britain, at at least 7000 years BC, bringing with them snails from mainland Europe. We know that snails have been used as a source of food in prehistoric times (back to 9,000 BC) and even farmed for that reason, which makes the suggestion plausible.

By John Black

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