Agent-based models of the cultural evolution of occupational gender roles.

The causes of sex differences in human behaviour are contested, with 'evolutionary' and 'social' explanations often being pitted against each other in the literature. Recent work showing positive correlations between indices of gender equality and the size of sex differences in behaviour has been argued to show support for 'evolutionary' over 'social' approaches. This argument, however, neglects the potential for social learning to generate arbitrary gender segregation. In the current paper we simulate, using agent-based models, a population where agents exist as one of two 'types' and can use social information about which types of agents are performing which 'roles' within their environment. We find that agents self-segregate into different roles even where real differences in performance do not exist, if there is a common belief (modelled as priors) that group differences may exist in 'innate' competence. Facilitating role changes such that agents should move without cost to the predicted highest-rewards for their skills (i.e. fluidity of the labour market) reduced segregation, while forcing extended exploration of different roles eradicated gender segregation. These models are interpreted in terms of bio-cultural evolution, and the impact of social learning on the expression of gender roles.

Sociocultural drivers of body image and eating disorder risk in rural Nicaraguan women.

OBJECTIVE: Technological and economic globalisation has been suggested as a cause of increasing rates of body dissatisfaction and eating disorders globally, especially as regards the impact of mass media on internalised body ideals. This process is rarely observed in action, however. The current work investigates multiple aspects of body ideals, body image, sociocultural attitudes and eating attitudes in 62 Creole and Mestizo women living in communities at differing stages of technological development on the Caribbean coast of Nicaragua METHOD/RESULTS: In Study 1, women used 3D avatar software to create their own 'ideal' body without the constraints of ready-made stimuli. Analyses of resulting avatars showed that components of the ideal body shape (upper and lower body curvaceousness) but not body size (body mass) were associated with levels of film and television consumption. In Study 2, women completed measures of variables in the sociocultural model of eating disorder risk. As expected, body dissatisfaction mediated the relationship between internalisation of sociocultural body ideals and pathological eating attitudes. In contrast, body appreciation reduced pathological eating attitudes, via reduced body dissatisfaction. Finally, Study 3 measured sociocultural influences, body image and eating attitudes at 2 or 3 timepoints per woman; body dissatisfaction covaried with pathological eating attitudes across time. Ethnicity varied in its effects across studies. DISCUSSION: Together these data show that even at early stages of media acculturation, women may show similar patterns of association between sociocultural internalisation, body dissatisfaction and eating disorder risk as in high income nations. However, they also demonstrate unique aspects of this population's body shape ideals, and the independent protective effect of body appreciation.

Body dissatisfaction and eating disorders are increasing on a global scale. It has been suggested that increasing access to globalised media maybe one factor in rising risk of eating disorders in low- and middle-income countries. We examined 3-dimensional body ideals, body satisfaction, and eating disorder risk in a population with relatively recent access to mass media. We find that although women in these communities maintain higher body weight ideals, and greater body appreciation, than Western women, those women who are internalising globalised cultural messaging about appearance are at greater risk of body dissatisfaction and, in turn, increased risk of eating disorders. This was true both when comparing between women and looking at how individual women's attitudes varied over time. These data show that cultural messaging about appearance has implications for body image and eating disorder risk even in populations which do not have a long history of promoting thin ideals.

Lower weight loss expectations and healthier eating attitudes in older overweight and obese women attempting weight loss.

Weight loss outcomes in overweight and obese individuals may be influenced by individual weight loss expectations (WLEs). Research on these phenomena in older women is lacking. This cross-sectional study compared groups of younger and older women on their WLEs and related attitudes (body dissatisfaction and disordered eating). Twenty-six younger (18-38 years) and 33 older (60-78 years) overweight and obese women were recruited from a weight loss clinic, prior to treatment. Disordered eating attitudes and body dissatisfaction were assessed using validated questionnaires and a pictorial figure-choice scale. Participants reported 10 WLEs categorized according to personal, lifestyle and social factors. Overall, women with a higher body mass index had greater WLEs. Older women reported lower WLEs than younger women (-14.5 kg vs. -22.4 kg) in all categories except past weight. Older women perceived that career success would necessitate the greatest level of weight loss (-18.5 kg), whereas younger women derived their greatest WLEs from mass media (-28.5 kg). Both older and younger groups perceived that their families would be supportive of the smallest amount of weight loss (-8.4 and -17.6 kg, respectively). The groups did not differ on body dissatisfaction, but younger women's disordered eating attitudes were significantly higher (p < .001). Older overweight and obese women have lower WLEs than younger women but experience similar levels of body dissatisfaction and healthier eating attitudes. The attitudinal constructs underlying these differences may be useful in clinical practice to tailor age-specific weight loss interventions.

Facial appearance is a cue to oestrogen levels in women.

Although many accounts of facial attractiveness propose that femininity in women's faces indicates high levels of oestrogen, there is little empirical evidence in support of this assumption. Here, we used assays for urinary metabolites of oestrogen (oestrone-3-glucuronide, E1G) and progesterone (pregnanediol-3-glucuronide, P3G) to investigate the relationship between circulating gonadal hormones and ratings of the femininity, attractiveness and apparent health of women's faces. Positive correlations were observed between late follicular oestrogen and ratings of femininity, attractiveness and health. Positive correlations of luteal progesterone and health and attractiveness ratings were marginally significant. Ratings of facial attributions did not relate to hormone levels for women wearing make-up when photographed. There was no effect of sex of rater on the relationships between oestrogen and ratings of facial appearance. These findings demonstrate that female facial appearance holds detectable cues to reproductive health that are considered attractive by other people.