Cultural Macroevolution and Adaptation: Relative Evidence for Innovation, Vertical and Horizontal Transmission

什么过程产生了文化之间的异同？文化特征可以从父母群体传播到子女群体（垂直传播），可以跨越群体边界扩散（水平传播），并且可以作为独立创新出现。这些不同的文化宏观进化过程的相对重要性是人类学调查的核心，也是理解文化和生物进化是否相似的核心。本研究通过利用三个人类学中已有的数据来调查这些问题：1)标准跨文化样本（SCCS）， 2)东非数据库（EADb）和3)北美西部印第安人数据库（WNAI）。首先，研究人员将利用这些信息来检验单一性状的分布与社会之间的历史和地理距离之间的关系。接下来，他们将通过关注历史和地理距离背景下社会中特定特征的共同出现来研究这些模式的不同解释。这两个步骤都利用了层次模型，这是一种为空间数据开发的特殊形式的广义线性模型。这项研究为更广泛地研究人类文化多样性做出了两个核心理论贡献。首先，它考察了文化进化和生物进化之间类比的适当性。虽然很明显，人口具有特定的文化特征，但建立这些文化特征的机制还没有得到很好的理解。第二，通过区分性状传递和社会文化适应，阐明适应在促进文化多样性中的作用。

What processes produce similarities and differences among cultures? Cultural traits can be disseminated from parent to daughter populations (vertical transmission), can diffuse across population boundaries (horizontal transmission), and can emerge as independent innovations. The relative importance of each of these different processes of cultural macroevolution lies at the heart of anthropological investigation and to understanding whether cultural and biological evolution are alike. This research investigates these questions by taking advantage of data already available in three anthropological: 1) the Standard Cross-Cultural Sample (SCCS), 2) the East African Data Base (EADb), and 3) the Western North American Indian database (WNAI). First, the researchers will use this information to examine the relationship between the distribution of single traits and the historical and geographical distances between societies. Next, they will investigate different explanations for these patterns by focusing on the co-occurrence of particular sets of traits within societies in the context of historical and geographical distance. Both steps utilize hierarchical modeling, a special form of generalized linear modeling developed for spatial data. This research makes two central theoretical contributions to the broader study of human cultural diversity. First it investigates the appropriateness of the analogy between cultural and biological evolution. Although it is clear that populations are characterized by particular sets of cultural traits, the mechanisms by which these cultural traits are established are not well understood. Second, by distinguishing between trait transmission and social and cultural adaptation, this research will clarify the role of adaptation in contributing to cultural diversity.