This study examines the relationship between group exogamy and peace. None of the hypotheses were supported.

This book examines the difference between warless and warlike societies and attempts to determine the point at which a society becomes warlike. The author suggests that differences between warless and warlike societies are mostly organizational and hypothesizes that "unsegmented" societies, or societies that have a weaker sense of group identity and cohesion, will be more likely to be warless than "segmented" societies. Several tests are presented. Results generally support the hypothesis.

This study tests a common theory that predicts a positive relationship between exogamy and cross-allegiances between social units. Results did not support this prediction. Cross-allegiances were only weakly related to cross-cousin marriage.

Author proposes and presents evidence in support of the theory that most societies practice virilocal or patrilocal residence (this is the "normal" pattern" and that matrilocal residence is adopted when societies migrate to an already populated area.

This book examines the characteristics of warlike and warless foraging societies, as well as the transitional stages that occur when a society becomes warlike. Several predicted correlates of warfare frequency are supported.

In this study, the author empirically tests a formulation of Ellen Dissanayake's evolutionary theory of art, which argues that art evolved to promote group cohesion. The hypotheses derived from this theory and tested in this study specifically focus on ritual art and its relationships to various proxies for group cohesion such as community conflict and internal warfare. Results show that the presence of ritual art is significantly higher where certain measures of group cohesion are also higher (including lower internal warfare, lower conflict between communities of the same society, and lower frequency of violent conflict between groups within local communities).

This article suggests a general theory of conflict and violence that may help explain the conditions under which internal conflict co-occur or are differentiated.

This article offers a critique of the study by Divale and Harris (1976).

This study investigates the thwarting disorientation theory of suicide, suggesting that the rate of suicide in a society can be predicted from thwarting disorientation traits such as men’s divorce freedom and defiant homicide.

This study investigates the presence of feuding, arguing that a solely evolutionary or functional approach misses important inter-societal factors. Results indicate that while fraternal interest groups are associated with feuding, the presence of war and level of political integration also increase the likelihood of feuding.