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of plant and animal species leads to morphological and physiological changes that distinguish domesticated taxa from their wild ancestors. It is one of the most important technological innovations in human history and was the linchpin of the Neolithic revolution 13,000–10,000 years ago, in which groups of hunter-gatherers formed the sedentary agricultural societies that ultimately gave rise to current human cultures. Domestication gave rise to food surpluses, and this led to craft specializations, art, social hierarchies, writing, urbanization and the origin of the state. As a process of recent, rapid species evolution, domestication was of great interest to Charles Darwin when he formulated his thesis on the origin of species through natural selection. Evolutionary biologists, however, tend to view domestication as a special class of species diversification, distinct from species divergence through natural selection in the wild. Yet domestication can also be seen as a type of plant–animal co-evolution, conceptually similar to examples of evolutionary diversification driven by other multispecies interactions. Indeed, the spread of crop species, which today dominate landscapes across the planet, attests to the increased fitness of domesticated plant taxa and suggests that domestication is one of the most successful of all plant–animal mutualisms. Moreover, fungal species have been domesticated by ants and beetles, so domestication is not specific to Homo sapiens. Nevertheless, the role of human culture, including the intentional manipulation of plants as sources of delayed food returns, drives the domestication process in distinctive ways. The use of domestication as a model for the evolutionary process stems from an understanding of events associated with the origins of crop species (starting some 13,000 years ago) and from precise knowledge of the selective pressures experienced by domesticated taxa, which can be gleaned from archaeological data and ethnographic studies of traditional farming societies and hunter-gatherers. Archaeology, in particular, can establish a fossil framework in which changes in phenotypes can be tracked in space and time and dated relatively precisely, allowing the microevolutionary dynamics that accompany species diversific ation to be traced. Genetic information on crop species also provides a molecular framework in the study of this co-evolutionary process, linking selective mechanisms inferred from archaeological studies to the genes that drove the origin and diversification of crop plant species. In this Review, we discuss recent archaeological work that reveals the mechanisms of the adaptation of crop plants to cultivation in agricultural environments and human cultures, and we describe genetic and genomic studies into the nature of adaptive selection in the genomes of crop species. The focus on both genetic and archaeological insights provides a clear picture of the selective pressures that accompany crop origins and diversification. The view from these two vantage points can increase understanding of the nature of the evolutionary selection that accompanies plant domestication.