DNA evidence suggests the hunter-gatherers of Britain were importing wheat from their agrarian neighbors on mainland Europe as much as 8,000 years ago.
The discovery, published Thursday in Science, could mean there was more contact between early farmers and hunter-gatherers in Europe than was previously thought.
According to the archaeological record, farming first started in Europe in the Balkans about 9,000 years ago and slowly moved west over the following millenniums, eventually coming to mainland Britain about 6,000 years ago.
But in the recent study, researchers studying ancient submerged sediment cores off the Isle of Wight found evidence of wheat DNA in soils that date back 8,000 years ago.
So what is going on?
The research team, led by Robin Allaby of the University of Warwick, say that while they found evidence of wheat DNA in the soil, they could not find any trace of wheat pollen. That leads them to conclude that while wheat was eaten on the site, it was not grown there.
"In the absence of direct evidence, we suspect that this wheat represents food stuffs imported from the continent," the authors write.
But there is a snag here too: The authors note that there is a 400-year gap between the age of the soil in which the wheat DNA was found and the earliest known presence of farming in nearby European sites.
In the paper, they propose that earlier agrarian sites may be submerged in southern Europe.
The researchers also report that there was much more wheat DNA found in the top half of the 8 cm soil sample than in the bottom half.
In the bottom half of the sample (representing an earlier time period) the wheat DNA was responsible for 4% of the flowering plants signal. In the top half, it represented 81% of the signal, indicating that the importing of wheat grew over time.
In an essay accompanying the study Greger Larson, an archaeologist at the University of Oxford, who was not involved in the research, notes that the authors spent a lot of time making sure they were reading the evidence correctly.
"The strength of the study lies not only with the empirical evidence, but also in the careful consideration and refutation of myriad ways in which the wheat DNA signatures could be the result of false positives or contamination," he writes.
He adds that this unexpectedly early appearance of wheat in Britain should "force a rethinking of both the strength of the relationships between early farmers and hunter gatherers, and the origins of settled agricultural communities in Europe."