Genetic perspectives on crop domestication

Abstract

The process of crop domestication has long been a topic of active research for biologists, anthropologists and others. Genetic data have proved a powerful resource for drawing inferences on questions regarding the geographical origins of crops, the numbers of independent domestication events for a given crop species, the specific molecular changes underlying domestication traits, and the nature of artificial selection during domestication and subsequent crop improvement. We would argue that these genetic inferences are fundamentally compatible with recent archaeological data that support a view of domestication as a geographically diffuse, gradual process. In this review, we summarize methodologies ranging from quantitative trait locus mapping to resequencing used in genetic analyses of crop evolution. We also highlight recent major insights regarding the timing and spatial patterning of crop domestication and the distinct genetic underpinnings of domestication, diversification and improvement traits.

Figure I

Lineage history and gene trees for a crop with multiple origins. The lineage history is the large tree, shown in black, and reflects the fact that there are two domestication events. Neutral and domestication gene trees are shown in color; the same trees are shown both inside the lineage tree and independently in the lower left and right hand sides.

Figure 1

Why archaeology and genetics do not match. This figure shows the genealogy of seven lineages over time. Genetic approaches applied to the modern crop can only detect the lineage shown in red. By contrast, all lineages can potentially be detected using archaeological techniques.