The human selection of food plants cannot always have been aimed exclusively at isolating the traits typical of domesticated species today. Each phase of global change must have obliged plants and humans to cope with and develop innovative adaptive strategies. Hundreds of thousands of wild cereal seeds from the Holocene ‘green Sahara’ tell a story of cultural trajectories and environmental instability revealing that a complex suite of weediness traits were preferred by both hunter-gatherers and pastoralists. The archaeobotanical record of the Takarkori rockshelter in southwest Libya covering four millennia of human occupation in the central Sahara gives us a unique insight into long-term plant manipulation and cultivation without domestication. The success of a number of millets was rooted in their invasive-opportunistic behaviour, rewarded during their coexistence with people in Africa. These wild plants were selected for features that were precious in the past but pernicious for agriculture today. Reconnecting past practices with modern farming strategies can help us to seek out the best resources for the future.
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This research is part of the activity of The Archaeological Mission in the Sahara, Sapienza University of Rome. Funds have been granted by Sapienza University of Rome (Grandi Scavi di Ateneo) and by the Italian Minister of Foreign Affairs (DGSP) entrusted to S.d.L. Libyan colleagues of the Department of Archaeology in Tripoli and Ghat are thanked. Funds for morphometrical and genetic analyses were provided by the project ‘SELCE—SELvaticiCEreali: il futuro nella risposta delle piante ai cambiamenti climatici’, sect. Scientific and Technological Research (Sime n.2015.0033), funded by the FCRMO-Fondazione Cassa di Risparmio di Modena, directed by A.M.M. We thank E. Milburn and J. Dunne who helped to clarify some expressions in English.
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Mercuri, A.M., Fornaciari, R., Gallinaro, M. et al. Plant behaviour from human imprints and the cultivation of wild cereals in Holocene Sahara. Nature Plants 4, 71–81 (2018). https://doi.org/10.1038/s41477-017-0098-1
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