Archaeologists work in the Nanshan ruins, Nov 5, 2017. [Photo/Xinhua]

The team's studies on the remains of the cave-dwellers showed that they suffered dental cavities and other oral diseases that are common among humans in agrarian societies, said Wang Minghui, another team member and researcher with the institute.

"It further proves that Nanshan residents mastered some agricultural techniques," Wang said.

The finding has raised the question why the Nanshan ancestors continued to live in caves after beginning farming. It is traditionally believed that humans in agrarian societies would move from caves to more spacious homes due to explosive population growth.

"The Nanshan finding offers a new perspective for prehistoric study. We must consider more possibilities when talking about where our ancestors lived and what they lived on," Zhao said.

Excavation of the Nanshan ruins started in 2012. Scores of caves, thousands of items made from pottery, stone and bones, as well as eight tombs and two reservoirs, have been found at the site.