What does it mean that there are no documents in the Naihe ruins?

The basis for the popularization of farming: the emergence of cottages and settled life

In the era of gathering and hunting, humans had to move frequently in order to obtain food. In the agricultural era, people reclaimed wasteland, sowed seeds, and waited for harvest. Therefore, settled life became the need for agricultural production methods. On the basis of settled life, many villages where ethnic groups lived together were formed.