Zhejiang Museum Wulin Branch

This guide to the Zhejiang Museum's Wulin branch begins in 1973, when farmers digging an irrigation ditch near the Yao River struck carved ivory preserved in black wetland mud for seven thousand years. It follows the discovery of the Hemudu site and a small ivory plaque showing two birds flanking a sun, which archaeologists believe once helped rice farmers time their spring flooding by the calendar. Get that timing wrong, in a settlement this dependent on water, and a village starves.