From this approach, we have learned, for example, that the ability to digest milk as adults evolved within the last 10,000 years – and several times – in cultures that domesticated sheep, goats, or cattle. Similar studies have taught us that sensitivity to alcohol consumption and resistance to diseases like malaria and leprosy also evolved within the last several thousand years.
通过这个手段，我们认识到成人消化牛奶的能力其实是在近1万年内的进化成果——而且还发生了多次进化——并源自于那些懂得驯养绵羊，山羊和牛的文明。类似的研究也揭示出人类吸收酒精的敏感度，以及对疟疾和麻风病的免疫力也是最近几千年才进化出来的。