Cattle, goats, sheep, and pigs all have their origins as farmed animals in the so-called Fertile Crescent, a region covering eastern Turkey, Iraq, and southwestern Iran. This region kick-started the Neolithic Revolution. Dates for the domestication of these animals range from between 13 000 to 10 000 years ago.

Genetic studies show that goats and other livestock accompanied the westward spread of agriculture into Europe, helping to revolutionize Stone Age society. While the extent to which farmers themselves migrated west remains a subject of debate, the dramatic impact of dairy farming on Europeans is clearly stamped in their DNA. Prior to the arrival of domestic cattle in Europe, prehistoric populations weren’t able to stomach raw cow milk. But at some point during the spread of farming into southeastern Europe, a mutation occurred for lactose tolerance that increased in frequency through natural selection thanks to the nourishing benefits of milk. Judging from the prevalence of the milk-drinking gene in Europeans today—as high as 90 percent in populations of northern countries such as Sweden—the vast majority are descended from cow herders.

See the map below of the scale of tolerance vs intolerance of lactose with the lighter shaded countries being more tolerant. What does this map reveal? Why do you think that Australians tend to be tolerant of lactose when their country is so far south?

map from Food Beast - https://cdn.foodbeast.com.s3.amazonaws.com/content/wp-content/uploads/2012/11/Global-Lactose-Intolerance.png