Microbotanical evidence of domestic cereals in Africa 7000 years ago.

Marco Madella,Welmoed A Out,Donatella Usai,Philippa Ryan,Juan José García-Granero,Xiaoyan Yang

doi:10.1371/journal.pone.0110177

Abstract

The study of plant exploitation and early use of cereals in Africa has seen over the years a great input from charred and desiccated macrobotanical remains. This paper presents the results of one of the few examples in Africa of microbotanical analyses. Three grave contexts of phytolith-rich deposits and the dental calculus of 20 individuals were analysed from two Neolithic cemeteries in North and Central Sudan. The radiocarbon-dated phytoliths from the burial samples show the presence of Near East domestic cereals in Northern Sudan at least 7000 years ago. Phytoliths also indicate the exploitation of wild, savannah-adapted millets in Central Sudan between 7500 and 6500 years ago. The calculus samples contained starch grains from wheat/barley, pulses and millets, as well as panicoid phytoliths. This evidence shows that Near East domestic cereals were consumed in Northern Africa at least 500 years earlier than previously thought.

Highlights

Wheat (Triticum spp.) and barley (Hordeum vulgare L.) were domesticated 10,500 years ago in the Near East, from where they spread east and west [1]
The vegetal material recovered from these Neolithic Sudanese cemeteries originates from the plant exploitation strategies of human groups inhabiting the Nile Valley during the MidHolocene
The phytolith evidence from Ghaba’s graves highlights broad spectrum exploitation of local grasses from savannah-like environments, while the R12 sample reveals the use of cereals, which probably came from the north of the Nile Valley

Summary

Introduction

Wheat (Triticum spp.) and barley (Hordeum vulgare L.) were domesticated 10,500 years ago in the Near East, from where they spread east (to Central and South Asia) and west (to Europe and the Mediterranean basin, including North Africa) [1]. The oldest evidence of domesticated cereal crops in North Africa, dated at 4650–4350 cal BC, comes from the Fayum Neolithic at Kom W and K [2]. While seeds and fruits are occasionally found [6], [7], [8], they are very scarce. This scarcity has been attributed to taphonomy in relation to wet/arid cycles and high microbial activity [9], [10], and sometimes to inadequate archaeobotanical recovery [11]. The grinding of tubers and grass seeds has been suggested [7], [12] and phytolith analysis of quern stones from Conical Hill, Wadi Howar (4300 cal BC) in western Sudan, confirms the use of chloridoid and panicoid grasses [13]

Methods

Results

Conclusion