Why did the lactose tolerance mutation in the East African herders spread so rapidly within the population?

Question

Quizplus · Accepted Answer

The lactose tolerance mutation provided a selective advantage for survival during droughts. As herders migrated to areas with less water and vegetation, the ability to digest lactose allowed them to rely on milk from their livestock as a source of hydration and nutrients during periods when other food sources were scarce. This gave lactose tolerant individuals a higher chance of survival and reproduction, leading to the rapid spread of the mutation within the population.

Why Did the Lactose Tolerance Mutation in the East African