The aim of this paper is to account for the effect of mother's death on child survival in a historical population. Using comprehensive data on the early French Canadian population of Quebec, evidence is provided for a higher risk of dying for motherless children that remains significant over all childhood and long after the death of the mother. The specific effect of the loss of maternal care was estimated by comparing mortality before and after mother's death, furnishing a means to control for family heterogeneity. No differential in investment between genders was detected before age 3, but older girls suffered a three-fold higher susceptibility to mother's death than their male counterparts. This suggests that grown-up girls assuming the responsibilities of the missing mother had a lower chance of survival.

Data from 949 families of Caucasian and 400 families of Japanese ancestry who took part in the Hawaii Family Study of Cognition were used to ascertain the associations of parental cognitive ability, parental education and paternal occupation with offspring cognitive ability. In particular, analyses were focused on testing the possible moderating effects of parental socioeconomic status on the familial transmission of cognitive abilities. Parental cognitive ability was substantially associated and parental education and paternal occupation only trivially associated with offspring performance. In contrast to the findings of Turkheimer et al. (2003), there was no evidence in these data that familiality for cognitive abilities was lower in the lower as opposed to upper levels of socioeconomic status. These results were consistent across measures, ethnicity and sex of offspring.

evolutionary biologists mostly assume that polygyny increases sexual dimorphism in size because, under polygyny, larger males monopolize mating opportunities and pass on their ‘large male’ genes to their sons. available data on parent–child correlations in height among humans (homo sapiens) do not support the crucial assumption that height is transmitted along sex lines. this paper instead suggests that human sexual dimorphism in size emerged, not because men got taller, but because women got shorter by undergoing early menarche in response to polygyny. it further speculates that, rather than genetically transmitted, the sexual dimorphism may emerge anew in each generation in response to the degree of polygyny in society. the analysis of comparative data supports the prediction that polygyny reduces women’s height, but has no effect on men’s, and is consistent with the speculation that the origin of human sexual dimorphism in size may be cultural, not genetic.

It remains unclear whether the frequency of marital coitus does in fact decline universally across the life course, what shape that decay normally takes, and what best accounts for it: increasing marriage duration, women’s age or age of their partners. Using cross-sectional Demographic and Health Survey (DHS) data of 91,744 non-abstaining women in their first marriage, a generalized linear model is used to determine if there is a consistent pattern in the life course pattern of degradation in the frequency of marital coitus. Datasets were drawn from nineteen countries in Asia, Africa and the Americas. Use of very large samples allows proper disentangling of the effects of women’s age, husband’s age and marital duration, and use of samples from multiple countries allows consideration of the influence of varied prevailing fertility regimes and fertility-related practices on life course trajectories. It is found that declining coital frequency over time seems a shared demographic feature of human populations, but whether marriage duration, wife’s age or husband’s age is most responsible for that decline varies by country. In many cases, coital frequency actually increases with women’s age into their thirties, once husband’s age and marriage duration are taken into account, but in most cases coital frequency declines with husband’s age and marital duration.

Using data from Wave 1 of the Household Income and Labour Dynamics in Australia (HILDA) survey, this paper analyses the extent to which childlessness among Australian women aged 40–54 years varies according to the size and type of family in which they were brought up, and the level and type of schooling they had. Multilevel logistic analysis shows that having been educated in a non-government school, having stayed at school to year 12, having a small number of siblings, at age 14 having a father who was either dead or absent, at age 14 having a father who was employed in a professional occupation, or being a migrant from North or West Europe, North America, East Asia or South-East Asia, all are significantly associated with higher rates of childlessness among women in the 40–54 years age range. The effects of these early lifecourse variables on marital and socioeconomic status in later life, and hence on childlessness, are also considered. The implications of the findings for fertility trends and for Australia’s public debate are discussed.

Males traditionally predominate at upper achievement levels. One general view holds that this is due only to various social factors such as the ‘glass ceiling’ and lack of female role models. Another view holds that it occurs partly because of innate ability differences, with more males being at upper ability levels. In the last few decades, women have become more achievement focused and competitive and have gained many more opportunities to achieve. The present study examined one intellectual domain, international chess, to quantify its gender differences in achievement and to see if these have been diminishing with the societal changes. Chess is a good test domain because it is a meritocracy, it has objective performance measures, and longitudinal data of a whole population are available. Performance ratings overall and in the top 10, 50 and 100 players of each sex show large gender differences and little convergence over the past three decades, although a few females have become high achievers. The distribution of performance ratings on the January 2004 list shows a higher male mean and evidence for more male variation, just as with traits such as height. Career patterns of players first on the list between 1985 and 1989 show that top males and females entered the list at about the same age but females tend to play fewer games and have shorter careers. In this domain at least, the male predominance is large and has remained roughly constant despite societal changes.

Analyses of height variation using the 1970 UK national cohort study (12,508 children at age 10 and 5470 at age 16) found clear evidence that children of higher socioeconomic status (as measured by social class, crowding, tenure, type of accommodation, income and receipt of government financial assistance) were on average taller than children of lower socioeconomic status but there was little or no difference in average stature between children living in urban or rural areas. Significant differences in height remained for most of the variables after removing the effects of father’s social class suggesting that reliance on social class per se to explain height variation is inadvisable.

This cross-sectional study was carried out to investigate the frequency of consanguineous marriage in a group of army conscripts in Ankara and the factors affecting this. Of 4153 soldiers, 387 were married. The rate of marriage between first cousins was found to be 19·1%, and the overall rate of consanguineous marriage was 24·1%. Consanguineous marriage was found to be significantly prevalent among soldiers who were born in and still living in the Eastern region; among those who lived in villages; among those whose parents as well as themselves had low educational levels; and among those whose marriages were arranged by their families. Neither the payment of bride-price nor the presence of consanguinity between parents was a significant factor for consanguineous marriage. In addition, the age of the soldier and the age at marriage were significantly lower among soldiers married to first cousins than among soldiers whose marriages were not consanguineous.