Answer: The ability of adults to consume fresh milk occurred rapidly in Europe during the transition to agriculturalist lifestyles, as a byproduct of the adaptation to dairying. The molecular analysis of genetic variants in modern people suggests that the adaptation and evolution of this ability occurred rapidly.
Explanation: All humans can digest milk in infancy. But the ability to do so as an adult developed fairly recently, likely in the past 6000 years. . A genetic mutation appeared, somewhere near modern-day Turkey, that jammed the lactase-production gene permanently in the “on” position.
In summary, early humans evolved to consume dairy products as a byproduct of their adaptation to dairying. The ability of adults to consume fresh milk occurred rapidly in Europe during the transition to agriculturalist lifestyles. All humans can digest milk in infancy but the ability to do so as an adult developed fairly recently. A genetic mutation appeared, somewhere near modern-day Turkey, that jammed the lactase-production gene permanently in the “on” position.
Hope this helps, and have a great day!