About the cover
By sequencing and comparing the genomes of nine ancient Europeans that bridge the transition to agriculture in Europe between 8,000 and 7,000 years ago, David Reich and colleagues show that most present-day Europeans derive from at least three highly differentiated populations west European hunter-gatherers, ancient north Eurasians (related to Upper Palaeolithic Siberians) and early European farmers of mainly Near Eastern origin. They further propose that early European farmers had about 44% ancestry from a basal Eurasian population that split before the diversification of other non-African lineages. These results raise interesting new questions, for instance that of where and when the Near Eastern farmers mixed with European hunter-gatherers to produce the early European farmers. Cover: Leonardo Gonzalez.