A01_03

Combined radiocarbon dating and stable isotope analyses on Neolithic cereal finds identifies turning points in crop dynamics (ca. 6000-3000 BC)

Antolin F¹, Martínez-Grau H², Soteras R¹, Guidobaldi G³, Jaggi M³, Wyss K³, Bernasconi S³, Hajdas I³

¹German Archaeological Institute, Natural Sciences Unit, Berlin, Germany, ²IPNA, University of Basel, , Switzerland, ³ETH Zurich, , Switzerland

The SNF-Funded AgriChange project (www.agrichange.duw.unibas.ch) intends to reconstruct agricultural decision-making processes among early farmers. The identification of moments of agricultural changes and their correlation with environmental proxies was therefore a priority for the project. For this reason, a large number of radiocarbon dates (to date, ca. 250) and stable isotope analyses (ca. 1500) were obtained, thanks to the collaboration of several archaeologists and archaeobotanists with the project. Charred cereal grains of mostly barley, naked wheat, einkorn and emmer where used. The results indicate two important moments of change around 5300 BC and around 4000 BC/3700 BC. Carbon stable isotope analyses have been used to reconstruct water availability during crop growth (as an indicator of spring precipitation) and the relationship between crop changes and carbon stable isotope ratios have been explored at a regional level. Our results indicate that scarce water availability was sometimes a limiting factor affecting crop choice in the NW Mediterranean area, while excessive precipitation might have influenced crop choice in the Alpine Foreland ca. 3600 BC. Other changes (at ca. 4000 BC) observed in the Mediterranean Area and Southern Alps do not seem to have clear correlation with carbon stable isotope values and other factors (i.e. crop pests and cultural contacts) are argued.