Agricultural Crop Choices and Social Change in the Yellow River Valley, North Central China during the Late Neolithic and Early Bronze Age Alison Weisskopf, University College London he Mid/Late Neolithic and Early Bronze Age in north central China saw great socio- economic change, from egalitarian villages during the Yangshao period (4900–3000 bc) to more hierarchical social organization during the Longshan (3000–1850 bc) to the rise of complex societies and the emergence of the irst city state at Erlitou in the Early Bronze Age Erlitou Period (1850–1100 bc) (Liu 2004, 4; Ma 2005, 3). his paper will examine whether social developments are charted by changes in agricultural crop choices. Archaeobotanical data from phytolith (silica bodies formed in the epidermis of plants) samples collected from four archaeological sites, Xipo, Erlitou, Huizui and Baligang, in Henan, north central China (Figure 11.1), have been used to examine changes in the crop repertoire, from broomcorn millet (Panicum miliaceum) to foxtail millet (Setaria italica) to rice (Oryza sativa). Figure 11.1. Map of China showing site distribution.