Archaeologists found that this region gradually evolved from tribes to chiefdoms during the Bronze Age.

### 解释 chiefdoms 是 chiefdom 的复数形式。chief 意思是"首领、酋长"，后缀 -dom 表示"领域、状态、集体"，组合起来指"由酋长统治的社会形态"，即"酋邦制"。