Department of Anthropology, University of Washington, Seattle, WA 98195;
Department of Anthropology, University of Utah, Salt Lake City, UT 84112
Proc Natl Acad Sci U S A. 2021 Mar 30;118(13). doi: 10.1073/pnas.2016134118.
Research examining institutionalized hierarchy tends to focus on chiefdoms and states, while its emergence among small-scale societies remains poorly understood. Here, we test multiple hypotheses for institutionalized hierarchy, using environmental and social data on 89 hunter-gatherer societies along the Pacific coast of North America. We utilize statistical models capable of identifying the main correlates of sustained political and economic inequality, while controlling for historical and spatial dependence. Our results indicate that the most important predictors relate to spatiotemporal distribution of resources. Specifically, higher reliance on and ownership of clumped aquatic (primarily salmon) versus wild plant resources is associated with greater political-economic inequality, measuring the latter as a composite of internal social ranking, unequal access to food resources, and presence of slavery. Variables indexing population pressure, scalar stress, and intergroup conflict exhibit little or no correlation with variation in inequality. These results are consistent with models positing that hierarchy will emerge when individuals or coalitions (e.g., kin groups) control access to economically defensible, highly clumped resource patches, and use this control to extract benefits from subordinates, such as productive labor and political allegiance in a patron-client system. This evolutionary ecological explanation might illuminate how and why institutionalized hierarchy emerges among many small-scale societies.
研究制度化等级制度的倾向往往集中在酋邦和国家，而其在小规模社会中的出现仍然理解不足。在这里，我们利用北美太平洋沿岸 89 个狩猎采集社会的环境和社会数据，检验了制度化等级制度的多个假设。我们利用能够识别持续政治和经济不平等的主要相关因素的统计模型，同时控制历史和空间依赖性。我们的结果表明，最重要的预测因素与资源的时空分布有关。具体来说，对聚集的水生（主要是鲑鱼）和野生植物资源的更高依赖和所有权与更大的政治经济不平等有关，后者是内部社会排名、获得食物资源的不平等和奴隶制的综合指标。表示人口压力、标度压力和群体间冲突的变量与不平等的变化几乎没有相关性。这些结果与假设一致，即当个人或联盟（例如，亲属群体）控制对经济上可防御的、高度聚集的资源斑块的访问权限，并利用这种控制从下属中获取利益，例如在庇护-客户系统中的生产性劳动和政治忠诚时，等级制度将出现。这种进化生态解释可能阐明了制度化等级制度是如何以及为何在许多小规模社会中出现的。
