Lactose intolerance is actually the original state for (adult) humans, while lactase persistence is an evolved adaption in cultures that drink a lot of unfermented dairy.
Which kind of proves that dairy is a significant enough part of many cultures' diet that it caused an evolutionary change! But these days you can buy lactase very cheaply in pill form, so really anyone can "have" the adaptation.
And many cultures with genetic lactose intolerance still consume a lot of fermented dairy.
Which kind of proves that dairy is a significant enough part of many cultures' diet that it caused an evolutionary change! But these days you can buy lactase very cheaply in pill form, so really anyone can "have" the adaptation.
And many cultures with genetic lactose intolerance still consume a lot of fermented dairy.