Abstract

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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Acknowledgements

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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Affiliations

  1. Laboratorio di Palinologia e Paleobotanica, Dipartimento di Scienze della Vita, Università degli Studi di Modena e Reggio Emilia, Modena, Italy

    • Anna Maria Mercuri
    •  & Rita Fornaciari
  2. Dipartimento di Scienze dell’Antichità, Sapienza Università di Roma, Rome, Italy

    • Marina Gallinaro
    •  & Savino di Lernia
  3. Department of Biological Sciences, School of Applied Sciences, University of Huddersfield, Huddersfield, UK

    • Stefano Vanin
  4. School of Geography, Archaeology and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa

    • Savino di Lernia

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Contributions

S.d.L. and A.M.M. conceived and planned the project. A.M.M. and S.d.L. wrote the paper. A.M.M. studied the archaeobotanical record and S.d.L. the stratigraphic and archaeological context. R.F. performed morphometry and data analysis. M.G. performed the GIS analysis. S.V. did the entomological study. S.d.L. designed and directed the excavations and field sampling. All authors read and approved the final manuscript.

Corresponding authors

Correspondence to Anna Maria Mercuri or Savino di Lernia.

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