Risk factors of poor anthropometric status in children under five years of age living in rural districts of the Eastern Cape and KwaZulu-Natal provinces, South Africa

Objectives: Factors associated with children’s anthropometric status were determined.Design: Secondary analysis was done using data from a cross-sectional survey including children under five years of age (n = 2 485) and their mothers in rural districts of the Eastern Cape and KwaZulu-Natal provinces, South Africa.Methods: Data generated by questionnaire and anthropometric indices were used to construct a logistic regression model, taking into account hierarchical relationships of risk factors to determine the odds of a child being stunted, underweight or overweight. Statistical significance was set at p < 0.05.Results: Factors associated with stunting were child of male gender (odds ratio (OR) = 1.233), the mother’s perception that child was not growing well (OR = 1.346), household receiving no food handouts (OR = 0.719) and mother not making important household decisions (OR = 0.760). Underweight was associated with child of male gender (OR = 1.432), low maternal education (OR = 1.720), mother’s perception that child was not growing well (OR = 2.526), any current breastfeeding (children < 24 months: OR = 2.022), and prior gastrointestinal symptoms (OR = 1.527). Factors associated with child overweight were the household not having a regular source of income (OR = 1.473), low maternal education (OR = 0.595) and mother’s perception that child is not growing well (OR = 0.361).Conclusion: Boys were more likely to be stunted and/or underweight.  children of mothers with less than five years schooling were more likely to be underweight. A regular source of household income was associated with child overweight/obesity.Keywords: child malnutrition; risk factors; stunting; underweight; overweight; rural; South Afric

Effects of the Distribution of Female Primates on the Number of Males

The spatiotemporal distribution of females is thought to drive variation in mating systems, and hence plays a central role in understanding animal behavior, ecology and evolution. Previous research has focused on investigating the links between female spatiotemporal distribution and the number of males in haplorhine primates. However, important questions remain concerning the importance of spatial cohesion, the generality of the pattern across haplorhine and strepsirrhine primates, and the consistency of previous findings given phylogenetic uncertainty. To address these issues, we examined how the spatiotemporal distribution of females influences the number of males in primate groups using an expanded comparative dataset and recent advances in Bayesian phylogenetic and statistical methods. Specifically, we investigated the effect of female distributional factors (female number, spatial cohesion, estrous synchrony, breeding season duration and breeding seasonality) on the number of males in primate groups. Using Bayesian approaches to control for uncertainty in phylogeny and the model of trait evolution, we found that the number of females exerted a strong influence on the number of males in primate groups. In a multiple regression model that controlled for female number, we found support for temporal effects, particularly involving female estrous synchrony: the number of males increases when females are more synchronously receptive. Similarly, the number of males increases in species with shorter birth seasons, suggesting that greater breeding seasonality makes defense of females more difficult for male primates. When comparing primate suborders, we found only weak evidence for differences in traits between haplorhines and strepsirrhines, and including suborder in the statistical models did not affect our conclusions or give compelling evidence for different effects in haplorhines and strepsirrhines. Collectively, these results demonstrate that male monopolization is driven primarily by the number of females in groups, and secondarily by synchrony of female reproduction within groups

The Reproductive Ecology of Industrial Societies, Part I : Why Measuring Fertility Matters.

Is fertility relevant to evolutionary analyses conducted in modern industrial societies? This question has been the subject of a highly contentious debate, beginning in the late 1980s and continuing to this day. Researchers in both evolutionary and social sciences have argued that the measurement of fitness-related traits (e.g., fertility) offers little insight into evolutionary processes, on the grounds that modern industrial environments differ so greatly from those of our ancestral past that our behavior can no longer be expected to be adaptive. In contrast, we argue that fertility measurements in industrial society are essential for a complete evolutionary analysis: in particular, such data can provide evidence for any putative adaptive mismatch between ancestral environments and those of the present day, and they can provide insight into the selection pressures currently operating on contemporary populations. Having made this positive case, we then go on to discuss some challenges of fertility-related analyses among industrialized populations, particularly those that involve large-scale databases. These include "researcher degrees of freedom" (i.e., the choices made about which variables to analyze and how) and the different biases that may exist in such data. Despite these concerns, large datasets from multiple populations represent an excellent opportunity to test evolutionary hypotheses in great detail, enriching the evolutionary understanding of human behavior