Snails Reveal How Ireland Was Colonized 8,000 Years Ago
By Rebekah Marcarelli | Jun 20, 2013 09:48 AM EDT
Researchers have found evidence of the human migration from the Pyrenean region of France to Ireland using snails, the mollusks could have hitched a ride with the travelers or were brought along as a snack.
The team discovered the Irish snails were almost genetically identical to a species in France, even though they were thousands of miles apart, according to a University of Nottingham press release.
The only explanation for the similarity of the snails is they were carried over by humans, most likely about 8,000 years ago.
"There is a very clear pattern, which is difficult to explain except by involving humans," said Dr. Angus Davidson, Reader in Evolutionary Genetics at the University of Nottingham who led the study with PhD candidate Adele Grindon. "If the snails naturally colonized Ireland, you would expect to find some of the same genetic type in other areas of Europe, especially Britain. We just don't find them."
Dr. Davidson said there are records of the Stone Age or Mesolithic people actually eating and farming the snails.
"The highways of the past were rivers and the ocean - as the river that flanks the Pyrenees was an ancient trade route to the Atlantic, what we're actually seeing might be the long lasting legacy of snails that hitched a ride, accidentally or perhaps as food, as humans travelled from the South of France to Ireland 8,000 years ago," Davidson said.
Davidson believes this ties into the previous belief the group of people colonized Ireland.
A lot of plants and animals found in Ireland haven't made it over to nearby Britain. The team thinks this makes the snail's passage even more significant.
"You would think that anything that gets to Ireland would go through Britain, but it has been a longstanding mystery as to why Ireland is so different from Britain. For these snails, at least, the difference may be that they hitched a ride on a passing boat," Davidson said.
Here is the full article published in the journal Plos One.