This study analyzes the relationship between communal democracy and family size. Results show a weakly significant negative correlation between communal leadership and family size. Authors suggest that this relationship could be challenged based on the known curvilinear relationship between family size and cultural complexity. However, several further tests suggest that there are grounds for maintaining that family size has some independent influence on the existence of communial democracy.

Controlling for community type, the researchers examine a potential relationship between family size (nuclear vs. extended) and communal leadership (hereditary vs. elected) in an effort to suggest potential predictors of hierarchical structures in societies. They claim support for their hypothesis that societies with nuclear families will be more likely to have democratic communal leadership, across four different community types.

Researchers tested four models of leadership for qualities and correlates that could predict the transmission of leadership cross-culturally. Researchers sampled 60 societies from the Probability Sample Files, coding for 24 variables. Support was found for the prevalence of the collective action model and the prestige model, with a lack of support found for the dominance leadership model.

This study investigates the relationship between domestic organization (i.e. family structure and size) and democracy at both the communal and supracommunal levels. The authors suggest that the prevalence of independent monogamous families in Europe in the Late Middle Ages may have facilitated the political evolution toward democracy.

This study proposes that polygyny, unilineal descent organization and large extended families could be regarded as universal negative predictors of communal democracy. Crosstabulations show that Christianity is positively associated with communal democracy and negatively associated with polygyny, and thus the authors suggest that Christianity influenced the development of democracy in Europe through its discouraging of polygyny and unilineal descent organization.

The present study attempts to replicate the Ember, Ember, and Russett (1992) worldwide finding that fighting rarely occurs between democracies in a sample of eastern African societies. Following the earlier study, the authors considered internal warfare to be an analog of international warfare and measures of political participation analogous to democracy. The researchers also explore if there is an association between political participation and committing atrocities. Contrary to past findings, internal warfare was not predicted by the same set of variables as the 1992 study, but there is an inverse relationship between committing atrocities and political participation. However, when additional variables were added, internal warfare was significantly predicted by less political participation.

This study explores the evolution of family systems in non-industrial agricultural societies based on environmental conditions. First, the authors conduct a multi-evolutionary simulation for each family system: absolute nuclear families (nuclear with unequal inheritance), egalitarian nuclear families (nuclear with equal inheritance), stem families (extended families with unequal inheritance), and community families (extended families with equal inheritance). Second, they use Spearman's rank correlation analyses to assess the relation between the 186 non-industrial societies and the types of inheritance relationships, either parent-child (nuclear or extended) or inter-sibling (strongly biased or equal). The results show that the four core family systems are related to wealth and land resources. Other relevant findings are that low polygyny is related to agricultural societies, higher poverty levels to extended families, and accelerated wealth accumulation to strongly biased inheritance.

This paper adds to a body of research which analyzes the persistence of institutional features in societies over time by testing for association between local democracy (succession by consensus among preindustrial groups) and various measures of democracy in contemporary societies. The researchers conclude that beliefs and values which perceive democracy as a viable political structure may be an important mediating mechanism in producing and maintaining democratic instututions over time.

This book investigates the origins of supernatural and religious beliefs. The author tests associations between various types of beliefs (e.g. witchcraft, monotheism) and various societal characteristics (e.g. mobility, class stratification). Many hypotheses are supported. Theoretical discussion is included, and the author posits that “the belief in a particular kind of spirit springs from experiences with a type of persisting sovereign group whose area of jurisdiction corresponds to that attributed to the spirit” (175).

This study examines several correlates of the shape of floor plans of dwellings. Authors find that "whether a culture is settled or nomadic, the form of its family and the presence or absence of status distinctions are related to its house type, and the house types can in turn be inferred from the floor plan." Curvilinear houses are associated with polygyny and nomadism and rectilinear houses are associated with sedentarism, extended families, and status distinctions.