"We found a number of grains of rice at the sites from the middle and late stages of Shangshan Culture, much more than at early-stage sites," Jiang says.

"It shows that, as time went by, rice farming increased and eating it became even more popular."

Painted pottery is seen as another important symbol of prehistoric culture. A variety of vessels at the exhibition are further proof of the brilliance of Shangshan Culture.

Chen Keshuang, a researcher and curator at the National Museum of China, says pottery items excavated from the sites are the earliest of their kind found in China.