This study offers a preliminary exploration into the relationships between demography and childcare. Most of the hypotheses presented in this paper are are not formally tested, but are examined using previous research. These hypotheses should be used to inform future research. One hypothesis tested using limited data found that male biased sex ratios are likely to exist in societies where males contribute more calories to the diet than females.

This study evaluates recent research on the roles of fathers in child development in hunting-gathering, simple farming, and pastoral communities around the world. The authors review previously conducted studies as well as highlight the varying theoretical approaches that many of these previous studies have taken.

Genetic, linguistic, and geographic data can be used to explain the distribution of cultural units ("semes") and to understand the evolutionary mechanisms of culture. Three broad models of cultural transmission attempt to explain why cultures share semes: (1) Cultural diffusion, emphasizing horizontal transmission. (2) Local adaptation, where trail-and-error learning leads to the independent adoption of semes by different peoples living in similar environments. (3) Demic diffusion, which emphasizes vertical and frequency-dependent transmission. Authors test the explanatory power of each model using cultural, genetic, linguistic and geographic data from 36 African cultures.

Considerable variation has been observed in allomaternal nursing (breast-feeding by individuals other than mothers) behavior across contemporary foraging populations: while relatively common in some populations, it is rare or absent among others. Here the authors examine data on allomaternal nursing from 12 previous studies of foraging societies and utilize a worldwide sample of 104 cultures to assess global variation in allomaternal nursing.

This paper examines patterns of cultural learning in pastoralist societies and compares them to those found in hunter-gatherer societies. The study analyzed 198 texts from 13 pastoralist cultures in the eHRAF World Cultures database and found that most cultural skills and knowledge were acquired in early childhood, with parents and non-parental adults as the primary sources of transmission. Teaching was the most common form of learning across all age groups, with minimal variation in transmission between different age groups. While similarities were found between the cultural learning patterns of pastoralists and hunter-gatherers, pastoralists were less likely to mention learning from peers and more likely to mention learning via local enhancement and stimulus enhancement. The importance of teaching did not increase with age in pastoralist societies, unlike in hunter-gatherer societies.

Social scientists are equivocal as to the importance of teaching (as contrasted with other forms of learning) in traditional societies. While many cultural anthropologists have downplayed the importance of teaching, cognitive psychologists often argue that teaching is a salient human universal. Here the authors investigate cultural transmission among 23 hunter-gatherer populations to explore the relative importance of teaching among foragers.

The biological success derived from cumulative culture and cooperation and their association with ancestral group structure is examined. It is suggested that inclusive fitness cannot explain extensive cooperation in hunter-gatherers because in most of the foraging societies examined, most individuals in residential groups are unrelated. These large social networks may explain why humans are capable of social learning.

In this article, the authors reconsider the polygyny threshold model in order to account for the "polygyny paradox." This paradox, as the authors define it, is the trend away from polygyny as societies adopt stratified agricultural economies. This is despite an increase in both the importance of material wealth and greater leaves of wealth inequality both of which would otherwise suggest increased polygyny. The authors develop a new model that does account for this paradox.