Historically rice-farming societies have tighter social norms in China and worldwide

Significance Rice is a highly interdependent crop. Rice required far more labor than dryland crops like wheat, and rice’s irrigation networks forced farmers to coordinate water use. To deal with these demands, rice villages developed strong norms for labor exchange. Using China as a natural test case, we compare nearby provinces that differ in rice and wheat, but share the same ethnicity, religion, and national government. In survey data from over 11,000 Chinese citizens, rice-farming provinces report tighter norms than traditionally wheat-growing provinces. Rice also predicts tight norms around the world. These data suggest that China’s agricultural past still shapes cultural differences in the modern day—and perhaps explain why East Asia has tighter social norms than the wheat-growing West.