This article examines the relationship between HIV/AIDS and several parameters of a nation’s demography, including income, mortality, labor, fertility, and homicide rates. Associations were supported by statistical tests. Regional differences are considered; Europe and the Muslim area had lower level of women’s HIV/AIDS infection. Four cultural adaptations to combat STDs are discussed.

Can physiological variation in human populations be attributed to environmental variables? Arguing for the importance of phylogenetic comparative methods, the authors present the results of previous research by Holden & Mace (1997) on lactose intolerance as well as introduce new research on sex ratio at birth. The authors suggest that global variance in sex ratio at birth is an adapted response to the physiological costs of giving birth to boys in high fertility populations.

This article discusses the variation in sex ratios at birth among human populations and the possible explanations for this variation. One possible explanation is the timing of intercourse and its relationship to the frequency of intercourse, which can affect the timing of conception. The article presents evidence that the male/female sex ratios of 148 countries declined with total fertility rates and polygyny intensity and increased with contraception use in correlational analysis. These results were independent of mother's age and level of economic development. The predictive effect of polygyny and contraception disappeared when total fertility was added to the equation. The article also considers other possible explanations for the variation in sex ratios, such as genetics, hormones, nutrition, and social factors.

In this article, the authors seek to understand the connection between male resource-holding potential and male mating success. This connection has been suggested by behavioral ecologists as a way of explaining differing rates of polygyny across cultures. The authors investigate this relationship by testing the relationship between rates of polygyny and male control of local subsistence sites among North American societies during the period of contact. They find a positive relationship between these two variables for both terrestrial and aquatic game, but not for gathered plants. This suggests support for the theory.

The researchers examine associations between male status and various measures of reproductive success among foraging/non-foraging, and monogamous/polygynous societies in order to test the "egalitarian hypothesis" which predicts lower status effects in hunter-gatherer groups. Contrary to this hypothesis, they find that male social status is equally significantly associated with reproductive success in foraging and nonforaging societies. Additional support is found for the "mating effort" hypothesis, which predicts that male reproductive success will be more associated with fertility than offspring mortality in polygynous societies, leading the authors to make various suggestions regarding the evolutionary mechanisms at play.

This article seeks to understand male-female bonding by testing the relationship between male contribution to subsistence (a proxy for male provisioning) and female reproductive success in foraging societies. Analysis supports a positive association.

The researchers examine Boserup's (1970) theory that variation in traditional agricultural practices shape gender roles by examining the relationship between historical plough use and contemporary fertility rates and preferential attitudes towards fertility. Contrary to expectation, tests show a negative relationship between plough use and both of these variables. The authors theorize that since children are less capable of performing the intensive labor required by plough agriculture compared to hoe agriculture, adoption of the plough deincentivized increased fertility and reduced its value among agriculturalists.

This study tests the weaning food availability hypothesis, that both the introduction of foods other than breastmilk and the cessation of breastfeeding will vary by society's subsistence type. This hypothesis has implications for demography, as accelerated weaning can lead to increases in both mothers' fertility (due to decreased birth intervals) and infant mortality (due to the presence of pathogens in new foods).

Textor summarizes cross-cultural findings on polygyny pertaining to cultural, environmental, psychological, and social phenomena.

In this paper, the authors argue against the findings presented in Hay & Bauer (2007) which suggest a positive correlation between population size and phoneme inventory size in languages. In order to do so, they highlight some methodological issues in the previous study, as well as other studies addressing similar questions. To address these issues, the authors conducted their own study using a larger and more representative sample of phoneme inventories drawn from the PHOIBLE knowledge base, and applied a more rigorous statistical analysis using a hierarchical mixed model. The results indicate that correlations between population size and phoneme inventory size are quite small when compared to differences among language family groups, and that the phoneme-population relationship fluctuates around zero between families, suggesting that any relationship between population and phoneme inventory size does not generalize to language as a whole. The author concludes that the correlations seen between population and phoneme inventories are likely to be artifacts, and do not find compelling reason to consider population size as a potential causal factor in the development of phonological systems.