Prehistoric Plant Remains Highlight Diverse Origins of Cereal Domestication

“We have studied the available archaeobotanical evidence (charred plant remains) from Pre-Pottery Neolithic sites in southwest Asia dated to approximately 11,600 to 10,700 years ago, and we can conclude that the importance we have hitherto attributed to cereals such as wheat and barley needs to be re-evaluated as other plants such as legumes – e.g. lentils, beans and peas – also played a crucial role during this time period, particularly in the eastern Fertile Crescent, e.g. Iran and Iraq, and southeast Turkey” says postdoc and archaeobotanist Amaia Arranz-Otaegui from the Centre for the Study of Early Agricultural Societies at the University of Copenhagen.

The origins of domesticated cereals

Not only did Neolithic communities from various regions across southwest Asia exploit a different range of plants – and did thus not rely exclusively on cereals – but the evidence also suggests that the different plant exploitation strategies could have contributed to important chronological dissimilarities during the emergence of morphologically domesticated species:

“Our results indicate that in the southern Levant (e.g. modern-day Jordan, Israel, Palestine and southern Syria), cereals were predominant during the Pre-Pottery Neolithic A (PPNA, 11,600-10,700 years ago) and domesticated cereals, which eventually became the cornerstones of agriculture, appeared around 10,700-10,200 years ago. But in the eastern Fertile Crescent, where cereals were not commonly exploited during the PPNA, domesticated cereals appear around 400-1000 years later. We know that plant domestication was a process that occurred in multiple regions and involved several plant species, so it is likely that in those regions where cereal exploitation was not common practice, similar management processes involving plants such as legumes could have existed,” Amaia Arranz-Otaegui points out.

Tell Qarassa North, Southern Syria, early Pre-Pottery Neolithic B, 10700-10200 cal BP). One of the earliest sites in southwest Asia with evidence of morphologically domesticated wheat and barley

Credit: Juan José Ibañez

Arranz Otaegui conducted the study “Regional diversity on the timing for the initial appearance of cereal cultivation and domestication in southwest Asia” with colleagues from Spain (Instituto Mila i Fontanals, CSIC, Instituto Internacional de Investigaciones Prehistoricas de Cantabria) and England (University Colledge London) when she was still employed at the University of the Basque Country.