Antipodal pattern of millet and rice demography in response to 4.2 ka climate event in China

The response of population and agriculture to abrupt climate events remains a matter of heated debates, especially the societal collapses related to the 4.2 ka event. Long-term interaction between regional demography and millet-rice agriculture in China provide a unique opportunity to study this issue. Here using a newly database of radiocarbon dates and archaeobotanical data spanning the Neolithic-Bronze Age from different regions in China, we address the response and resilience of demography and agriculture to the 4.2 ka event. Regional populations show an antipodal pattern of boom in north and northwest (NW) and bust in south and southeast (SE) China during 4300–3500 cal a BP. This pattern coincided with the prosperity and breakdown of millet and rice agricultures contemporaneously, respectively. Our study reveals that drought-induced enlargement of farmland and trans-Eurasian cultural exchange promoted the sustainability of millet agriculture and population in NW China, and combined effects of cooling and flooding events and social crises caused a decline in rice agriculture and population in SE China. The diverse response and resilience of human societies to the 4.2 ka event has been attributed to both climatic anomalies and cultural exchange across different regions. In sum, the complex societies with high stratification and hierarchies were more vulnerable to abrupt climate events than low stratified societies open to exchanges during the middle to late Holocene.