This article examines marital residence and sibling coresidence among horticulturalists in the South American lowlands. The authors reject a hypothesis that patrilocality is the defining trait of Amazonian tropical forest culture. Results on horticulturalists are compared with findings on hunter-gatherers: horticulturalists tend to be more uxorilocal. Empirical analysis also suggests that women tend to live with more kin later in life, and in large villages headmen live with more kin than nonheadmen.

This article examines whether intergenerational wealth transmission perpetuates inequality among hunter-gatherers. The authors consider three types of wealth: embodied, material, and relational. Empirical analysis of wealth transmission in five cultures suggests that, in many cases, a parent’s wealth is associated with a child’s life chances. Gini coefficients suggest that hunter-gatherer cultures have low to moderate wealth inequality overall: very low by current world standards but not non-existent.

In this article Hames addresses the long-standing disagreements between evolutionary theories regarding human warfare (more specifically between Rousseauian and Hobbesian frameworks). This study posits that while most current and previous research focuses on the discrepancies between the frequency and intensity with which warfare takes place between hunter-gatherer and large-scale societies, the ability for societies to live in peace with their neighbors despite the possibility for warfare, is the most important evolutionary trait. Coexisting peacefully is what distinguishes human socially and politically from chimpanzees whereas warfare itself is a more primitive trait humans share with previous ancestors. Hames concludes that going forward, use of phylogenetic methods to control for common ancestry, and use of archaeological data would lead to new and more comprehensive findings. Although largely a review of principal warfare literature, Hames does present an original statistical finding on adult violence mortality which is reported below.

High infant and child mortality rates are suggested to be one of the most enduring and important features of ancestral human environments, referred to as the Environment of Evolutionary Adaptedness (EEA). These rates contrast with the very low rates of infant and child mortality among many industrialized nations since the 19th and 20th centuries. The authors compare data from recent hunter-gatherer and agricultural societies, historical records, and non-human primates in attempt to quantitatively describe infant and child mortality rates during the EEA.

Grooming of conspecifics is thought to play an important social role among nonhuman primates, but the function and relative importance of such grooming among humans is unknown. Here the authors compare time spent grooming and conversing among six small-scale societies with grooming data from 69 nonhuman primate species. They test the hypothesis that conversation evolved among humans as an alternative way to obtain the social benefits (such as building and maintaining social alliances) of grooming in large groups.

The present research examines the residence patterns of 34 hunter-gatherer societies and 34 lowland South American horticulturalist societies using census data. Contrary to the traditional view of patrilocal postmarital residence being prevalent, the present findings suggest more multilocality in residence patterns for hunter-gatherer and horticulturalist societies. The author concludes that hunter-gatherers are slightly patrilocal and horticulturalists slightly matrilocal.

While it is widely accepted that there are a multitude of variables that contribute to a society’s level of democracy, the authors of this study argue that the prevalence of consanguinity is one that is often overlooked. Using a sample of 70 nations, they tested the relationship between consanguinity (defined as marriage and subsequent mating between second cousins or closer relatives) and level of democracy (defined by both the Polity IV scale and the EIU Index) and found a significant negative relationship. Similarly, when controlled for a host of different variables in multiple regression analysis, the significant relationship between consanguinity and level of democracy held true.

This study tests possible explanations for sexual dimorphism in human post-reproductive life-spans. The author focuses on explanations involving male paternal investment and finds that men in agricultural societies are more likely to invest in their offspring than men in hunter-gatherer societies.

Researchers looked at four different demographic scenarios (altered mean vital rates (i.e., fertility and mortality), vital rate stochasticity, vital rate covariance, and periodic catastrophes) and their possible effects on the rapid population growth of contemporary human foragers and steady population decline of chimpanzees. They evaluated these variables and the various conditions that would favor a more sustainable zero population growth (ZPG) among 10 small-scale subsistence human populations (Agta, Ache, Hadza, Hiwi, Ju/’hoansi, Gainj, Tsimane, Yanomamo, Northern Territory Aborigines, and Herero) and five wild chimpanzee groups (Gombe, Kanyawara, Mahale, Ngogo, and Taï). The results state that the most effective modifications towards ZPG would include a combination of more than one of the four demographic scenarios tested, with the most realistic solution including both vital rate alteration and an increase in catastrophes.

This article hypothesizes that ritual ecstasy was selected for as a way for hunter-gatherers to cope with resource uncertainty by unifying separate groups. Results support this hypothesis and suggest a relationship between resource stress and deities as well as dependence on animals and presence of zoomorphic deities.