DNA from an underwater site suggests that there was wheat in Britain 8,000 years ago — 2,000 years before farming arrived in the region.

The research suggests that wheat somehow made its way from the Neolithic farmers of Southern Europe to the Mesolithic hunter-gatherers of present-day Britain.

The farmers and hunter-gatherers may have been trading, said Robin G. Allaby, a plant geneticist at the University of Warwick and an author of the new study, which appears in the journal Science.

Stone tools found at the site resemble those found in northern France, another clue that there may have been trade between the two groups.