Ancient Wheat Genomes Illuminate Domestication, Dispersal, and Diversity

Abstract Ancient DNA (aDNA) promises to revolutionise our understanding of crop evolution. Wheat has been a major crop for millennia and has a particularly interesting history of domestication, dispersal, and hybridisation, summarised briefly here. We review how the fledgling field of wheat archaeogenomics has already contributed to our understanding of this complex history, revealing the diversity of wheat in ancient sites, both in terms of species and genetic composition. Congruently, ancient genomics has identified introgression events from wild relatives during wheat domestication and dispersal. We discuss the analysis of degraded aDNA in the context of large, polyploid wheat genomes and how environmental effects on preservation may limit aDNA availability in wheat. Despite these challenges, wheat archaeogenomics holds great potential for answering open questions regarding the evolution of this crop, namely its domestication, the different dispersal routes of the early domestic forms and the diversity of ancient agricultural practices. Not only will this research enhance our understanding of human history, but it will also contribute valuable knowledge about ancient selective pressures and agriculture, thus aiding in addressing present and future agricultural challenges.