One year after Zheng first visited the Jinuo people, in 1983, he was recruited by Yunnan Academy of Social Sciences to officially carry out his field research of the group.

During the whole of the 1980s, he visited every one of the more than 40 Jinuo villages, stayed with local people for up to eight months a year, and continues to visit them today.

Every time he arrives at a Jinuo village, he lives, hunts, forages for wild vegetables and farms with them. During the process he observes, befriends and talks with them. He also participates in important sacrificial, wedding and funeral ceremonies, striving to know every facet of their lifestyle.

Zheng is impressed by Jinuo people's solidarity and equality.

According to him, when he first visited the group, hunting was still an important way to make a living, just like their ancestors before them.

"They often hunted with several other villagers. When they successfully caught their prey, even it was only one pheasant, they followed a primitive egalitarian ritual, dividing the meat evenly so that every participant could share a portion," says Zheng.

And they often help each other in daily life.

"When one family has problems, all others offer a helping hand," Zheng says.

"I visited an old man in his 70s, who was almost blind and didn't have children or spouse. All the families in the village took turns to help him till his land and harvest his crops. When he passed away, villagers stopped all work for one day to hold the funeral. They all regarded it as an important issue.

"Old people and children seem to live a carefree life there, and people live harmoniously together," he adds.