An evolutionary account of status, power, and career in modern societies

We hypothesize that in modern societies the striving for high positions in the hierarchy of organizations is equivalent to the striving for status and power in historical and traditional societies. Analyzing a sample of 4,491 US men and 5,326 US women, we find that holding a supervisory position or being in charge of hiring and firing is positively associated with offspring count in men but not in women. The positive effect in men is attributable mainly to the higher proportion of childlessness among men in non-supervisory positions and those without the power to hire and fire. This effect is in accordance with the positive relationship between other status indicators and reproductive success found in men from traditional, historical, and modern societies. In women, we further find a curvilinear relationship between income percentile and offspring number by analyzing US census data, indicating that women may strive for resources associated with advancement rather than for status per se.     

Natural selection on male wealth in humans

Although genomic studies suggest that natural selection in humans is ongoing, the strength of selection acting on particular characteristics in human populations has rarely been measured. Positive selection on male wealth appears to be a recurrent feature of human agrarian and pastoralist societies, and there is some evidence of it in industrial populations, too. Here we investigate the strength of selection on male wealth, first in contemporary Britain using data from the National Child Development Study and then across seven other varied human societies. The British data show positive selection on male income driven by increased childlessness among low-income men but a negative association between personal income and reproductive success for women. Across cultures, selection gradients for male wealth are weakest in industrial countries and strongest in subsistence societies with extensive polygyny. Even the weakest selection gradients observed for male wealth in humans are as strong as or stronger than selection gradients reported from field studies of other species. Thus, selection on male wealth in contemporary humans appears to be ubiquitous and substantial in strength.     

Do high-status people really have fewer children?

Evolutionary discussions regarding the relationship between social status and fertility in the contemporary U.S. typically claim that the relationship is either negative or absent entirely. The published data on recent generations of Americans upon which such statements rest, however, are solid with respect to women but sparse and equivocal for men. In the current study, we investigate education and income in relation to age at first child, childlessness, and number of children for men and women in two samples—one of the general American population and one of graduates of an elite American university. We find that increased education is strongly associated with delayed childbearing in both sexes and is also moderately associated with decreased completed or near-completed fertility. Women in the general population with higher adult income have fewer children, but this relationship does not hold within all educational groups, including our sample with elite educations. Higher-income men, however, do not have fewer children in the general population and in fact have lower childlessness rates. Further, higher income in men is positively associated with fertility among our sample with elite educations as well as within the general population among those with college educations. Such findings undermine simple statements on the relationship between status and fertility.     

Childlessness among American women

Abstract

The rate of childlessness in the United States has increased over the last two decades. Changing or differential rates by different segments of society have important implications for society. Most previous studies have relied on unrepresentative opportunistic samples to identify those segments of society with lower or higher rates of childlessness. These types of samples may misestimate both the number of women planning to remain childless and the magnitude of the correlates of childlessness. The present study uses these previous studies to identify predictor variables, but tests their significance using a recent national representative sample of women in the United States, aged 20–44: Cycle III of the National Survey for Family Growth, collected in 1982. The most important demographic factors are marital status and fecundity status, followed by age, race or ethnicity, education of the respondent, labor force status, and region. Father's education and mother's education are slightly, but not significantly, related to childlessness. Contrary to findings from less representative samples, urban‐rural differences and religion are not related to childlessness.     

Childlessness drives the sex difference in the association between income and reproductive success of modern Europeans

The association between reproductive success and income in economically developed societies remains a controversial and understudied topic. The commonly made statement that individuals with a higher income have fewer children defies evolutionary explanation. Here we present results from an analyses of the association between lifetime reproductive success (LRS) and income for modern Europeans from 13 countries. We examine the relationships among income, partner income, sex and LRS, and the role of childlessness in driving the relationships. For women, we find a negative association between LRS and income, while for men, we find a flat or slightly positive one. The sex difference in the association appears to be driven by income's sex-specific association with childlessness; men with a low income have a relatively high risk of childlessness, while women with a low income have a low risk of childlessness. Consequently, once childless people are excluded from the analysis, LRS is negatively associated with income for both sexes. We argue that the observed LRS–income associations may be an outcome of evolved behavioural predispositions operating in modern environments and conclude that, even though humans fail to maximise LRS at all income levels in modern settings, evolutionary theory can still help to explain sex differences in LRS.     

Pathways into childlessness: evidence of gendered life course dynamics

Using data from the first wave of the Netherlands Kinship Panel Study (NKPS) for 2867 women and 2195 men aged 40 to 79, this study examines to what extent educational, employment and marital pathways shape the likelihood of remaining childless, and whether these pathways are gendered. The findings indicate that women and men have distinctive pathways into childlessness. Educational attainment increases the likelihood of remaining childless among women only. A stable career increases the likelihood of remaining childless among women, but it increases the likelihood of entering fatherhood. Years without a partner is positively associated with childlessness among both women and men. Not having had a partnership and having had multiple partnerships are strong determinants of childlessness, especially among men.     

Voluntary Childlessness Among American Men and Women in the Late 1980's

Abstract

Most studies of childlessness in the United States have relied on unrepresentative, opportunistic samples collected in a variety of ways. Thus, the relationship of various correlates to childlessness is not well known. Some studies have focused on demographic variables, but have not examined attitudinal factors associated with childlessness—something the opportunistic samples have been able to do. In this paper we examine both attitudinal and demographic factors associated with childlessness in the United States. The data used in this paper are from the National Survey of Families and Households collected in 1987 and 1988. The data set includes both demographic data, perceived advantages and disadvantages of having children, and attitudinal data about related social issues. Overall, the rate of voluntary childlessness was not high. Only 3.5 per cent of the men and 2.8 per cent of the women reported that they were childless and did not expect to have children. Only one category of people (unmarried men and women over the age of 35) had rates that exceeded ten per cent. A combined variable of age and marital status was the best predictor of childlessness. A scale of reasons or justifications for having children was the next best predictor. In addition, attendance at religious services, number of hours the respondents desired to work and education (for women only) were related to childlessness. Those who scored highly on measures of support for traditional families and support of extended families also tended to have lower rates of childlessness. Occupational status, religious denomination, and race, on the other hand, were not significantly related to childlessness. Measures of gender equality, religious fundamentalism, and support for mothers working were also not related to childlessness.     

Voluntary childlessness among American men and women in the late 1980's.

Most studies of childlessness in the United States have relied on unrepresentative, opportunistic samples collected in a variety of ways. Thus, the relationship of various correlates to childlessness is not well known. Some studies have focused on demographic variables, but have not examined attitudinal factors associated with childlessness--something the opportunistic samples have been able to do. In this paper we examine both attitudinal and demographic factors associated with childlessness in the United States. The data used in this paper are from the National Survey of Families and Households collected in 1987 and 1988. The data set includes both demographic data, perceived advantages and disadvantages of having children, and attitudinal data about related social issues. Overall, the rate of voluntary childlessness was not high. Only 3.5 per cent of the men and 2.8 per cent of the women reported that they were childless and did not expect to have children. Only one category of people (unmarried men and women over the age of 35) had rates that exceeded ten per cent. A combined variable of age and marital status was the best predictor of childlessness. A scale of reasons or justifications for having children was the next best predictor. In addition, attendance at religious services, number of hours the respondents desired to work and education (for women only) were related to childlessness. Those who scored highly on measures of support for traditional families and support of extended families also tended to have lower rates of childlessness. Occupational status, religious denomination, and race, on the other hand, were not significantly related to childlessness. Measures of gender equality, religious fundamentalism, and support for mothers working were also not related to childlessness.     

The effects of sex and childlessness on the association between status and reproductive output in modern society

Examining the association between socioeconomic status and reproductive output in modern societies has led to conflicting results. In this study, we used a representative sample of contemporary Swedish men and women to analyze possible reasons for the contradictory results. We found that the relationship between socioeconomic status—described here by income and highest educational level attained—and reproductive output is dependent on sex and the inclusion or exclusion of childless individuals. In men, there is a strong positive association between income/education and average offspring count if childless individuals are included in the analysis; this association is absent when such individuals are excluded. We attribute this reversal mainly to the higher proportion of childless individuals among men of lower socioeconomic background. Among other factors, female choice appears to be a major cause of this association because the proportion of men who never married increased with decreasing income category and educational level. In women, however, including and excluding childless individuals both yielded a negative association between income and average offspring count as well as a null or negative relationship between education and average offspring count.     

Family background, schooling and childlessness in Australia

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.     

Who remains childless?

Who are the men and women who are childless in their mid-30s? Life history data for a British cohort born in 1946 show that age at marriage and marital breakdown were clearly associated with childlessness. Women who were only children were more likely to be childless than those with siblings. Further, early menarcheal age, being highly qualified and having a high status occupation were indirectly related to childlessness. For men, particularly amongst those who had experienced a broken marriage, it was the most ambitious, the highly educated and those in professional occupations who were relatively more likely to be childless.     

Social-economic inequality in mortality among older mem amd women. Research on the role of health, life style, parental socio-economic status and psychosocial conditions

This article describes to what degree socio-economic differences exist among community living older men and women, and to what degree these differences are to be explained by health, behaviour, childhood and psychosocial conditions. The data are available from 1427 men and 1503 women (aged 55-85), participating in the Longitudinal Aging Study Amsterdam (LASA) in 1992/1993. As indicators of socio-economic status (ses) we used the highest level of education and net monthly income. Age-adjusted mortality risks for men and women with low income and for men with a low level of education are about 1.5 times as high as for to the persons with high income and educational level. Among men, but not among women, the difference in mortality risk between low and high status persons remains after adjustment for age, health status, and several risk factors. Differences in lifestyle, parental ses and psychosocial characteristics explain little to nothing of the age-adjusted ses-differentiation in mortality. It is concluded that ses-inequalities in mortality are present among Dutch men and, to a lesser extent among women, until high age, and are partly explained by the relatively large health problems of the lower status group.     

Factors in the incidence of childlessness in Canada: an analysis of census data

Due to the difficulties involved in attempting to determine the relative proportion of involuntary childlessness and of voluntary childlessness in a given population, many investigators insist that the problem can only be examined in small-scale studies using intensive psychological interviewing techniques. A method for assessing the causes of childlessness in a population using census materials is described. If a distinction is made between psychological and physiological causes, instead of between intentional and unintentional causes, it is possible to assess the relative importance of these causes using large-scale investigation techniques. Physiological causes include all physiological conditions which produce sterility. Psychological causes include both psychosomatic infertility and the voluntary decision not to have children. The method involves using the minimum rate of childlessness in a population group known to place a high value on fertility as an estimate of the rate of physiological childlessness in the population. This estimate is then subtracted from the childlessness rate observed in other population groups in the same society in order to determine the degree of psychological childlessness in these other population groups. This method was used to assess the causes of childlessness in Canada. Census materials were used to determine the minimum rate of childlessness among rural women in Quebec. Since this group is primarily Catholic and places a high value on children, its childlessness rate provides an estimate of the proportion of sterile couples in the population. This rate was then subtracted from the childlessness rates for urban Canadian women, and the remainder provided an estimate of psychological childlessness among urban women. Age of marriage was controlled for since rural women married at younger ages. Study findings were 1) the proportion of childlessness among urban women declined over the years as 15.2% of the women over 45 years old were childless while only 10.8% of the women, aged 30-44, were childless; 2) the proportion of physiological childlessness declined from 6.6% among women over 45 years old to 4.6% among women, aged 30-44; and 3) approximately 50% of the cases of childlessness among urban women were due to psychological factors. These findings do not support the contentions of some investigators that 10% of the population is sterile and that psychological childlessness is rare. Study findings were presented in tabular form.     

Long-term trends in marital status mortality differences in The Netherlands 1850-1970

This article describes the long-term trends in marital status mortality differences in the Netherlands using a unique dataset relating to the period 1850-1970. Poisson regression analysis was applied to calculate relative mortality risks by marital status. For two periods, cause-of-death by marital status could be used. Clear differences in mortality by marital status were observed, with strongly increasing advantages for married men and women and a relative increase in the mortality of widowed compared with non-married people. Excess mortality among single and formerly married men and women was visible in many cause-of-death categories, and this became more widespread during the last decades of the nineteenth century. Hypotheses are formulated that might explain why married men and women underwent a stronger decrease in mortality up until the end of World War II.     

Psychosocial Moderators the Effects of Transitioning Into Filial Caregiving on Mental and Physical Health

A life-course theoretical perspective guided this study to examine how effects on mental and physical health (depressive symptoms, hostility, global happiness, self-esteem, personal mastery, psychological wellness, self-rated physical health) of transitioning into filial caregiving for a sole surviving parent are moderated by prior relationship quality, filial obligation, race or ethnicity, education, income, employment status, marital status, and parental status. Results from models estimated using longitudinal data from 1,060 adults aged 25 to 65 years at baseline (National Survey of Families and Households, 1987 to 1994) suggested that life-course and contextual factors do contribute to patterning health risks of caregiving, often in different ways for men and women: For example, low income puts daughter caregivers at greater risk for decline in physical health, combining employment with filial caregiving is more problematic for daughters' mental health, and being an unmarried filial caregiver is more problematic for men. Heterogeneity in the experience of filial care needs further attention in future research.     

Social determinants of smoking in low- and middle-income countries: results from the World Health Survey

Introduction

Tobacco smoking is a leading cause of premature death and disability, and over 80% of the world''s smokers live in low- or middle-income countries. The objective of this study is to assess demographic and socioeconomic determinants of current smoking in low- and middle-income countries.

Methods

We used data, from the World Health Survey in 48 low-income and middle-income countries, to explore the impact of demographic and socioeconomic factors on the current smoking status of respondents. The data from these surveys provided information on 213,807 respondents aged 18 years or above that were divided into 4 pooled datasets according to their sex and country income group. The overall proportion of current smokers, as well as the proportion by each relevant demographic and socioeconomic determinant, was calculated within each of the pooled datasets, and multivariable logistic regression was used to assess the association between current smoking and these determinants.

Results

The odds of smoking were not equal in all demographic or socioeconomic groups. Some factors were fairly stable across the four datasets studied: for example, individuals were more likely to smoke if they had little or no education, regardless of if they were male or female, or lived in a low or a middle income country. Nevertheless, other factors, notably age and wealth, showed a differential effect on smoking by sex or country income level. While women in the low-income country group were twice as likely to smoke if they were in the lowest wealth quintile compared with the highest, the association was absent in the middle-income country group.

Conclusion

Information on how smoking is distributed among low- or middle-income countries will allow policy makers to tailor future policies, and target the most vulnerable populations.     

Pet companionship and depression: Results from a United States Internet sample

Abstract

Using Internet survey data from 2,291 respondents from the United States, we examined socio-demographic predictors of living with a cat or dog. Logistic regressions showed that, for men, being married, living with children, being Midwestern and non-urban increased odds of living with a pet. For women, being White, having a high income, living with children, and living in a rural setting increased odds for pet ownership. Multivariate analyses examining influences of gender, marital status, and pet ownership on depression (CES-D) scores, adjusting for potential confounders, revealed that unmarried women who live with a pet have the fewest depressive symptoms, and unmarried men who live with a pet have the most. These findings suggest that single women benefit from pet companionship, whereas single men may be burdened by it.     

Distribution of cardiovascular disease risk factors by socioeconomic status among Canadian adults

BACKGROUND: This study was designed to describe the distribution of risk factors for cardiovascular disease by socioeconomic status in adult men and women across Canada using the Canadian Heart Health Surveys Database. METHODS: The data were derived from provincial cross-sectional surveys done between 1986 and 1992. Data were obtained through a home interview and a clinic visit using a probability sample of 29,855 men and women aged 18-74 years of whom 23,129 (77%) agreed to participate. The following risk factors for cardiovascular disease were considered: elevated total plasma cholesterol (greater than 5.2 mmol/L), regular current cigarette smoking (one or more daily), elevated diastolic or systolic blood pressure (140/90 mm Hg), overweight (body mass index and lack of leisure-time physical activity [less than once a week in the last month]). Education and income adequacy were used as measures of socioeconomic status and mother tongue as a measure of cultural affiliation. RESULTS: For most of the risk factors examined, the prevalence of the risk factors was inversely related to socioeconomic status, but the relationship was stronger and more consistent for education than for income. The inverse relationship between socioeconomic status and the prevalence of the risk factors was particularly strong for smoking and overweight, where a gradient was observed: 46% (standard error [SE] 1.4) of men and 42% (SE 4.3) of women who had not completed secondary school were regular smokers, but only 12% (SE 1.0) of men and 13% (SE 0.9) of women with a university degree were regular smokers. Thirty-nine percent (SE 1.4) of men and 19% (SE 3.8) of women who had not completed secondary school were overweight, compared with 26% (SE 2.6) of male and 19% of female university graduates. The prevalence of leisure-time physical inactivity and elevated cholesterol was highest in both men and women in the lowest socioeconomic category, particularly by level of education. INTERPRETATION: The differences in the prevalence of risk factors for cardiovascular disease between socioeconomic groups are still important in Canada and should be considered in planning programs to reduce the morbidity and mortality from cardiovascular disease.     

Evolution of obesity by social status in France, 1981-2003

Although France is less affected by the rise in obesity than neighboring countries, the prevalence of obesity has increased, changing the distribution of this pathology in the population. We analyze this evolution by social status, education, income and gender, region of residence, using the three French national Health Surveys conducted in 1981, 1992 and 2003. The average body weight of both women and men has increased in France since 1981 and accelerated since the 1990s. This trend is obtained among all age groups. Nevertheless, this process did not affect all socioeconomic groups similarly. Geographical differences increased between north-east, where the prevalence of obesity is higher, and the Mediterranean region, where it is lower. Likewise, the gap between social and occupational categories has greatly widened: obesity has increased much faster among farmers and blue-collar workers than among managers and professionals. In contrast to women, poorer men are not more likely to be more obese than others. Our findings suggest that differences in BMI values increased substantially among social groups in France, in particular among women.     

Social determinants of self-reported health in women and men: understanding the role of gender in population health

Background

Women and men share similar health challenges yet women report poorer health. The study investigates the social determinants of self-reported health in women and men, and male-female differences in health.

Methods

Data on 103154 men and 125728 women were analysed from 57 countries in the World Health Survey 2002–2004. Item Response Theory was used to construct a composite measure of health. Associations between health and determinants were assessed using multivariate linear regression. Blinder-Oaxaca decomposition partitioned the inequality in health between women and men into an “explained" component that arises because men and women differ in social and economic characteristics, and an “unexplained" component due to the differential effects of these characteristics. Decomposition was repeated for 18 countries in the World Health Organization (WHO) African region and 19 countries in the WHO European region.

Results

Women''s health was significantly lower than men''s. Health was associated with education, household economic status, employment, and marital status after controlling for age. In the pooled analysis decomposition showed that 30% of the inequality was “explained", of which almost 75% came from employment, education, marital status. The differential effects of being in paid employment increased the inequality. When countries in Africa and Europe were compared, the “explained" component (31% and 39% respectively) was largely attributed to the social determinants in the African countries and to women''s longevity in the European countries. Being in paid employment had a greater positive effect on the health of males in both regions.

Conclusions

Ways in which age and the social determinants contribute to the poorer health status of women compared with men varies between groups of countries. This study highlights the need for action to address social structures, institutional discrimination and harmful gender norms and roles that differently influence health with ageing.