Regional diversity on the timing for the initial appearance of cereal cultivation and domestication in southwest Asia.

Recent studies have broadened our knowledge regarding the origins of agriculture in southwest Asia by highlighting the multiregional and protracted nature of plant domestication. However, there have been few archaeobotanical data to examine whether the early adoption of wild cereal cultivation and the subsequent appearance of domesticated-type cereals occurred in parallel across southwest Asia, or if chronological differences existed between regions. The evaluation of the available archaeobotanical evidence indicates that during Pre-Pottery Neolithic A (PPNA) cultivation of wild cereal species was common in regions such as the southern-central Levant and the Upper Euphrates area, but the plant-based subsistence in the eastern Fertile Crescent (southeast Turkey, Iran, and Iraq) focused on the exploitation of plants such as legumes, goatgrass, fruits, and nuts. Around 10.7-10.2 ka Cal BP (early Pre-Pottery Neolithic B), the predominant exploitation of cereals continued in the southern-central Levant and is correlated with the appearance of significant proportions (∼30%) of domesticated-type cereal chaff in the archaeobotanical record. In the eastern Fertile Crescent exploitation of legumes, fruits, nuts, and grasses continued, and in the Euphrates legumes predominated. In these two regions domesticated-type cereal chaff (>10%) is not identified until the middle and late Pre-Pottery Neolithic B (10.2-8.3 ka Cal BP). We propose that the cultivation of wild and domesticated cereals developed at different times across southwest Asia and was conditioned by the regionally diverse plant-based subsistence strategies adopted by Pre-Pottery Neolithic groups.