When early humans began to move away from hunting and gathering, their genes took a bit longer than previously though to catch up.

According to the Washington Post, a new study published in the journal Nature Communications suggests that early humans may have taken thousands of years to be able to digest dairy. For their study, the researchers sequenced the genomes of 13 subjects to find the transition to agriculture and farming.

The study authors chose the Great Hungarian Plain in the 5,000 years before the Iron Age because it represented a good mix of early humans.

"Our findings show progression towards lighter skin pigmentation as hunter and gatherers and non-local farmers intermarried, but surprisingly no presence of increased lactose persistence or tolerance to lactose" study senior author Ron Pinhasi, a professor at the University College Dublin (UCD), said in a press release. "This means that these ancient Europeans would have had domesticated animals like cows, goats and sheep, but they would not yet have genetically developed a tolerance for drinking large quantities of milk from mammals."

The genetic evidence showed that cultural practices like farming and metal work came from a shift in genes.

"The genomes do seem to shift as new technologies come about," study co-author Daniel Bradley, a professor at Trinity College Dublin, told the Post. "You can't look at this and think that farming and metallurgy are technologies that come into the culture by osmosis. They come with people. Genomes and technology migrate together.

"We thought we'd look at some genes that had been previously discussed as being important, that we knew human populations had selected for during the course of human pre-history," he said. "Ireland is the place in the world with the highest concentration of lactose tolerance, and undoubtedly that's to do with a heavy reliance on drinking unprocessed milk in pre-history, and a culture focused on dairying."