9分達人雅思閱讀真題還原及解析3（簡體書）

Although humans have established many types of societies throughout history, sociologists and anthropologists tend to classify different societies according to the degree to which different groups within a society have unequal access to advantages such as resources, prestige or power, and usually refer to four basic types of societies. From least to most socially complex they are clans, tribes, chiefdoms and states.
Clan
These are small-scale societies of hunters and gatherers, generally of fewer than 100 people,who move seasonally to exploit wild (undomesticated) food resources. Most surviving huntergatherer groups are of this kind, such as the Hadza of Tanzania or the San of southern Africa.Clan members are generally kinsfolk, related by descent or marriage. Clans lack formal leaders,so there are no marked economic differences or disparities in status among their members.
Because clans are composed of mobile groups of hunter-gatherers, their sites consist mainly of seasonally occupied camps, and other smaller and more specialised sites. Among the latter are kill or butchery sites-locations where large mammals are killed and sometimes butchered-and work sites, where tools are made or other specific activities carried out. The base camp of such a group may give evidence of rather insubstantial dwellings or temporary shelters, along with the debris of residential occupation.
Tribe
These are generally larger than mobile hunter-gatherer groups, but rarely number more than a few thousand, and their diet or subsistence is based largely on cultivated plants and domesticated animals. Typically, they are settled farmers, but they may be nomadic with a very different, mobile economy based on the intensive exploitation of livestock. These are generally multi-community societies, with the individual communities integrated into the larger society through kinship ties.