A new genomic analysis of 7,000-year-old Mesolithic remains found in modern-day Sweden has identified the earliest known markers of lactase persistence in Europe. The study suggests that certain Northern European hunter-gatherer groups developed the ability to digest milk significantly earlier than previously thought.
This research challenges the prevailing theory that the 'milk-drinking gene' only became widespread with the arrival of Yamnaya pastoralists from the steppes. It indicates a convergent evolutionary process driven by the unique environmental stresses of the sub-arctic climate.