chapter  3
A BRIEF HISTORY OF MILK CONSUMPTION: Europe and the U.S.
Pages 27

The evolution of lactase persistence is closely tied to animal domestication and the use of domesticated mammals for milk. Dairying became an important part of subsistence practices only in the Old World, and as we saw in the previous chapter, lactase persistence is also unique to populations with ancestry there. Within the Old World, dairying was not ubiquitous, and lactase persistence evolved only among populations that made use of mammalian milk after weaning. Along with genetic adaptations to milk, the cultural valuation of dairy animals and dairy products became core components of dairying societies.