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The evolution of domesticated cereals was a protracted, complex process with shifting selection pressures and repeated introgressions as plants and society co-evolved. We show a temporal series of archaeogenomes from a single archaeological site that reveals the evolutionary trajectory of sorghum under domestication. Contrary to expectations we find no evidence for a domestication bottleneck but a steady decline in diversity over time coupled with an accumulating mutation load. Dynamic selection pressures acted sequentially on architectural and nutritional domestication traits, and local adaptation including in phytochrome A metabolism. Durra type sorghum adaptively introgressed into the local population assuming environmental and donating domestication traits. These results reveal a model of domestication in which genomic adaptation and deterioration is a uniformitarian process unrestricted to the distant past. |