Pubertal maturation is independent of family structure but daughters of divorced (but not dead) fathers start reproduction earlier

Several evolutionary hypotheses predict that girls growing up without a father present in the family mature and start reproduction earlier because father absence is a cue for environmental harshness and/or uncertainty that favours switching to a precocious life-history strategy. Most studies supporting these hypotheses have been performed in contemporary Western societies where the father absence is usually caused by divorce or abandonment. We performed a large retrospective cohort study in the mid-twentieth century Estonia, where different types of orphans and daughters of divorced fathers were exactly matched with girls from bi-parental families based on age, birth year, urban/rural origin and socioeconomic position of the family. Pubertal maturation, assessed on the basis of the breast development rate, did not associate with family structure. Daughters of divorced fathers started reproduction on average 9.2 months earlier than girls from bi-parental families and also tended to start reproduction earlier than girls whose fathers were dead. This finding is consistent with the view that fathers prone to divorce (and/or their spouses) differ from the rest of the population and also from the fathers prone to early death in some important characteristics that affect the reproductive rates of their daughters.     

Does Absence Matter?

This paper examines the effects of three different types of father absence on the timing of life history events among women in rural Bangladesh. Age at marriage and age at first birth are compared across women who experienced different father presence/absence conditions as children. Survival analyses show that daughters of fathers who divorced their mothers or deserted their families have consistently younger ages at marriage and first birth than other women. In contrast, daughters whose fathers were labor migrants have consistently older ages at marriage and first birth. Daughters whose fathers died when they were children show older ages at marriage and first birth than women with divorced/deserted fathers and women with fathers present. These effects may be mediated by high socioeconomic status and high levels of parental investment among the children of labor migrants, and a combination of low investment, high psychosocial stress, and low alloparental investment among women with divorced/deserted fathers. Our findings are most consistent with the Child Development Theory model of female life history strategies, though the Paternal Investment and Psychosocial Acceleration models also help explain differences between women in low paternal investment situations (e.g., father divorced/abandoned vs. father dead). Father absence in and of itself seems to have little effect on the life history strategies of Bangladeshi women once key reasons for or correlates of absence are controlled, and none of the models is a good predictor of why women with deceased fathers have delayed life histories compared with women whose fathers are present.     

Father absence, parental care, and female reproductive development

This study examines female reproductive development from an evolutionary life history perspective. Retrospective data are for 10,847 U.S. women. Results indicate that timing of parental separation is associated with reproductive development and is not confounded with socioeconomic variables or phenotypic correlations with mothers' reproductive behavior. Divorce/separation between birth and 5 years predicted early menarche, first sexual intercourse, first pregnancy, and shorter duration of first marriage. Separation in adolescence was the strongest predictor of number of sex partners. Multiple changes in childhood caretaking environment were associated with early menarche, first sex, first pregnancy, greater number of sex partners, and shorter duration of marriage. Living with either the father or mother after separation had similar effect on reproductive development. Living with a stepfather showed a weak, but significant, association with reproductive development, however, duration of stepfather exposure was not a significant predictor of development. Difference in amount and quality of direct parental care (vs. indirect parental investment) in two- and single-parent households may be the primary factor linking family environment to reproductive development.     

Determining the roles of father absence and age at menarche in female psychosocial acceleration

Paternal investment theory and psychosocial acceleration theory hold that father absence and stressful experiences, respectively, accelerate reproductive development. Accumulating evidence is consistent with these theories yet important questions remain. In this study, we use a two-part structural equation model and data from 342 female undergraduates to address two of these questions: First, what is the role of father absence in female psychosocial acceleration, controlling potentially confounding aspects of environment and family structure? Second, to what extent does age at menarche mediate environmental and family structure effects on sexual debut? Findings indicated that many aspects of environment and family structure could be summarized with two factors—socio-economic status (SES) and fragmented family structure. We found that among those who had experienced sexual debut, exposure to temporary father departure (one year or more) in the context of an intact family hastened menarche, which in turn accelerated sexual debut. However, this type of father absence did not predict experience of sexual debut (or not). Fragmented family structure (which also implies some degree of father absence) appeared to increase the likelihood that participants had experienced sexual debut, but did not predict age at menarche or age at sexual debut among who had debuted. SES was not associated with any aspects of reproductive development, controlling for fragmented family structure and age. We discuss our findings in relation to paternal investment theory, psychosocial acceleration theory, and life history theory. We then lay out future directions for researchers aiming to clarify the role of environment in reproductive trajectories.     

Father's death does not affect growth and maturation but hinders reproduction: evidence from adolescent girls in post-war Estonia

The popular concept of predictive–adaptive responses poses that girls growing up without a father present in the family mature and start reproduction earlier because the father''s absence is a cue for environmental harshness and uncertainty that favours switching to a precocious life-history strategy. Most studies supporting this concept have been performed in situations where the father''s absence is caused by divorce or abandonment. Using a dataset of Estonian adolescent girls who had lost their fathers over the period of World War II, we show that father''s death did not affect the rate of pubertal maturation (assessed on the basis of development of breasts and axillary hair) or growth. Father''s death did not affect the age of first birth but, contrary to predictions, reduced lifetime reproductive success. Our findings thus do not support the concept of predictive–adaptive responses and suggest that alternative explanations for covariation between fatherlessness and early maturation are required.     

Environmentally Contingent Reproductive Strategies in Mayan and Ache Males

This research explores male reproductive parameters, particularly the timing of first reproduction, in two traditional populations. Predictions are drawn from theoretical arguments that have their roots in evolutionary psychology and behavioral ecology, and that interpret variation in reproductive outcomes as environmentally contingent adaptations. In both Ache and Mayan samples, father absence, predicted to act as a stressor that causes precocious sexuality and reproduction as well as unstable pair bonds, did not affect the timing of first reproduction in male offspring in the expected way. Father absence in Mayan men, however, was found to be associated with responses to questionnaire items indicating lack of willingness to pay time and energy costs to maintain existing sexual unions. The results suggest that father absence affects male mating strategy, but that strategic differences did not translate into reproductive outcomes in the sample. In the Mayan population, education was associated with early reproduction, more lifetime sex partners, and higher fertility, which was also contrary to the predicted pattern based on a life-history tradeoff approach. Parental resources were associated with earlier reproduction in the Mayan sample, confirming the prediction that restricted resources should delay reproduction.     

Early stress predicts age at menarche and first birth,adult attachment,and expected lifespan

Life history theory suggests that in risky and uncertain environments the optimal reproductive strategy is to reproduce early in order to maximize the probability of leaving any descendants at all. The fact that early menarche facilitates early reproduction provides an adaptationist rationale for our first two hypotheses: that women who experience more risky and uncertain environments early in life would have (1) earlier menarche and (2) earlier first births than women who experience less stress at an early age. Attachment theory and research provide the rationale for our second two hypotheses: that the subjective early experience of risky and uncertain environments (insecurity) is (3) part of an evolved mechanism for entraining alternative reproductive strategies contingent on environmental risk and uncertainty and (4) reflected in expected lifespan. Evidence from our pilot study of 100 women attending antenatal clinics at a large metropolitan hospital is consistent with all four hypotheses: Women reporting more troubled family relations early in life had earlier menarche, earlier first birth, were more likely to identify with insecure adult attachment styles, and expected shorter lifespans. Multivariate analyses show that early stress directly affected age at menarche and first birth, affected adult attachment in interaction with expected lifespan, but had no effect on expected lifespan, where its original effect was taken over by interactions between age at menarche and adult attachment as well as age at first birth and adult attachment. We discuss our results in terms of the need to combine evolutionary and developmental perspectives and the relation between early stress in general and father absence in particular. This work was supported by The University of Melbourne Department of Obstetrics and Gynaecology. James S. Chisholm is Professor in the School of Anatomy and Human Biology at the University of Western Australia. He is an anthropologist whose interests lie in the fields of human behavioral biology, evolutionary ecology, life history theory, and parental investment theory, where he focuses on infant social-emotional development, the development of reproductive strategies, and the integration of evolutionary, developmental, and cultural psychology and public health. Julie A. Quinlivan is Associate Professor in Obstetrics and Gynaecology at the University of Melbourne and Head of the Maternity Care Program at the Royal Women’s Hospital, Melbourne. Her interests are teenage pregnancy, domestic violence, child abuse prevention, and high-risk pregnancy. Rodney W. Petersen is Senior Lecturer in Obstetrics and Gynaecology at the University of Melbourne and Senior Consultant in Obstetrics and Gynaecology at the Royal Women’s Hospital and Sunshine Hospital in Melbourne. His interests are in psychosocial aspects of women’s health and cancer. David A. Coall is a Ph.D. student in the School of Anatomy and Human Biology at the University of Western Australia. His main interest lies in the application of evolutionary theory within an epidemiological framework. He is currently working on the synthesis of life history theory, parental investment theory, and parent-offspring conflict theory in exploring factors that influence variation in human birth weight and placental weight.     

Facial and bodily correlates of family background

It has been suggested that absence of the father during early childhood has long-reaching effects on reproductive strategy and development of offspring. This paper reports two studies designed to investigate the physical characteristics of daughters associated with father absence. Study 1 used a facial averaging method to produce composite images of faces of women whose parents separated during their childhood (who were 'father absent'), women whose parents remained together, but had poor quality relationships and women whose parents were together and had good quality relationships. Images were then rated by male and female judges. Father absence and poor parental relationships were associated with apparent facial masculinity and reduced attractiveness in daughters. Poor parental relationships were also associated with reduced apparent health. Study 2 compared family background with body measurements and found that father absence or a poor quality relationship between parents were associated with body masculinity (high waist-to-hip ratio) and increased weight-for-height and adiposity. These results highlight the possibility of physical masculinization being associated with purported father absence 'effects'.     

Menarcheal age and subsequent patterns of family formation

Abstract

We examine whether age at menarche affects age at first marriage or first birth using two samples of U.S. women. Data are drawn from the Tremin Trust, a longitudinal study of menstrual cycles that recruited white women who were students at the University of Minnesota and from a survey of a nationally representative sample of white women born between 1900 and 1910. Regression models with cubic splines were used to analyze the relationship between age at menarche and age at first marriage. Cox proportional hazard models were used to examine the effect of age at menarche on the interval between marriage and first birth. Unlike earlier work, we found that once secular trends in both age at marriage and age at menarche were taken into account, there was no evidence that age at menarche affects either age at marriage or the timing of first births in these U.S. women.     

Father absence and age at menarche

Life history data, attractiveness ratings of male photographs, and attitudes towards partnership and child-rearing of 321 women were used to test four evolutionary models (quantitative reproductive strategy, male short-age, polygyny indication, and maternal reproductive interests) which attempt to explain the influence of family composition on reproductive strategies. Links between early menarche and other markers of reproductive strategy were investigated. Childhood stress and absence of a father figure, whether genetically related or not, were found to have accelerated menarche whereas having younger siblings decelerated it. Early menarche was associated with attractiveness ratings, the number of partners desired for the immediate future, and the early onset of intimate relationships. It was not linked with sociosexual orientation, mate choice criteria, and investment in the subjects’ own children, but these three markers were interrelated. The implications of the findings for the four evolutionary models are discussed.     

Paternal investment and status-related child outcomes: timing of father's death affects offspring success

Recent work in human behavioural ecology has suggested that analyses focusing on early childhood may underestimate the importance of paternal investment to child outcomes since such investment may not become crucial until adolescence or beyond. This may be especially important in societies with a heritable component to status, as later investment by fathers may be more strongly related to a child's adult status than early forms of parental investment that affect child survival and child health. In such circumstances, the death or absence of a father may have profoundly negative effects on the adult outcomes of his children that cannot be easily compensated for by the investment of mothers or other relatives. This proposition is tested using a multigenerational dataset from Bangalore, India, containing information on paternal mortality as well as several child outcomes dependent on parental investment during adolescence and young adulthood. The paper examines the effects of paternal death, and the timing of paternal death, on a child's education, adult income, age at marriage and the amount spent on his or her marriage, along with similar characteristics of spouses. Results indicate that a father's death has a negative impact on child outcomes, and that, in contrast to some findings in the literature on father absence, the effects of paternal death are strongest for children who lose their father in late childhood or adolescence.     

Menarcheal age and subsequent patterns of family formation

We examine whether age at menarche affects age at first marriage or first birth using two samples of U.S. women. Data are drawn from the Tremin Trust, a longitudinal study of menstrual cycles that recruited white women who were students at the University of Minnesota and from a survey of a nationally representative sample of white women born between 1900 and 1910. Regression models with cubic splines were used to analyze the relationship between age at menarche and age at first marriage. Cox proportional hazard models were used to examine the effect of age at menarche on the interval between marriage and first birth. Unlike earlier work, we found that once secular trends in both age at marriage and age at menarche were taken into account, there was no evidence that age at menarche affects either age at marriage or the timing of first births in these U.S. women.     

Why father absence might precipitate early menarche: The role of polygyny

An evolutionary model of conditional reproductive strategies argues that girls whose fathers are absent or make little parental investment experience early puberty. However, such a conditional strategy cannot be adaptive unless the absence of the girl's father at the microlevel is predictive of some recurrent feature of the macrosocial system and early puberty is advantageous in the system. I argue that father absence is indicative of the degree of polygyny (simultaneous and serial) in society. Polygyny of both kinds creates a shortage of women in reproductive age, and thus, early puberty will be advantageous. Available comparative data indicate that the degree of polygyny is associated with a decrease in the mean age of menarche across societies, as is the divorce rate a presumptive index of serial polygyny, in strictly monogamous societies.     

The Null Relation between Father Absence and Earlier Menarche

Researchers have claimed that the absence of a biological father accelerates the daughter’s menarche. This claim was assessed by employing a large and nationally representative sample of Indonesian women. We analyzed 11,138 ever-married women aged 15+ in the Indonesian Family Life Survey 2015. We regressed age at menarche on the interaction of father absence (vs. presence) and mother absence (vs. presence) at age 12 with or without childhood covariates. For robustness checks, we performed a power analysis, re-ran the same specification for various subgroups, and varied the independent variable of interest. All results produced a null relation between father absence and age at menarche. The power analysis suggests that a false negative was unlikely. Our review of the literature indicates that the claim of the relation between father absence and earlier menarche was based on weak statistical foundations. Other studies with higher-quality datasets tended to find no relation, and our results replicated this tendency. Therefore, the influence of father absence does not appear to be universal.     

Reproductive strategy, sexual development and attraction to facial characteristics

Sexual reproduction strategies vary both between and within species in the level of investment in offspring. Life-history theories suggest that the rate of sexual maturation is critically linked to reproductive strategy, with high investment being associated with few offspring and delayed maturation. For humans, age of puberty and age of first sex are two developmental milestones that have been associated with reproductive strategies. Stress during early development can retard or accelerate sexual maturation and reproduction. Early age of menarche is associated with absence of younger siblings, absence of a father figure during early life and increased weight. Father absence during early life is also associated with early marriage, pregnancy and divorce. Choice of partner characteristics is critical to successful implementation of sexual strategies. It has been suggested that sexually dimorphic traits (including those evident in the face) signal high-quality immune function and reproductive status. Masculinity in males has also been associated with low investment in mate and offspring. Thus, women's reproductive strategy should be matched to the probability of male investment, hence to male masculinity. Our review leads us to predict associations between the rate of sexual maturation and adult preferences for facial characteristics (enhanced sexual dimorphism and attractiveness). We find for men, engaging in sex at an early age is related to an increased preference for feminized female faces. Similarly, for women, the earlier the age of first sex the greater the preference for masculinity in opposite-sex faces. When we controlled sexual dimorphism in male faces, the speed of sexual development in women was not associated with differences in preference for male facial attractiveness. These developmental influences on partner choice were not mediated by self-rated attractiveness or parental relationships. We conclude that individuals assort in preferences based on the rapidity of their sexual development. Fast developing individuals prefer opposite-sex partners with an increased level of sexually dimorphic facial characteristics.     

Menarcheal timing is accelerated by favorable nutrition but unrelated to developmental cues of mortality or familial instability in Cebu,Philippines

Understanding the determinants of pubertal timing, particularly menarche in girls, is an important area of investigation owing to the many health, psychosocial, and demographic outcomes related to reproductive maturation. Traditional explanations emphasized the role of favorable nutrition in maturational acceleration. More recently, work has documented early maturity in relation to markers of familial and environmental instability (e.g. paternal absence), which are hypothesized to serve as cues triggering adaptive adjustment of life history scheduling. While these studies hint at an ability of human females to accelerate maturity in stressful environments, most have focused on populations characterized by energetic excess. The present study investigates the role of developmental nutrition alongside cues of environmental risk and instability (maternal absence, paternal absence, and sibling death) as predictors of menarcheal age in a well-characterized birth cohort born in 1983 in metropolitan Cebu, the Philippines. In this sample, which was marked by a near-absence of childhood overweight and obesity, we find that menarcheal age is not predicted by cues of risk and instability measured at birth and during childhood and early adolescence, but that infancy weight gain and measures of favorable childhood nutrition are strong predictors of maturational acceleration. These findings contrast with studies of populations in which psychosocial stress and instability co-occur with excess weight. The present findings suggest that infancy and childhood nutrition may exert greater influence on age at menarche than psychosocial cues in environments characterized by marginal nutrition, and that puberty is often delayed, rather than accelerated, in the context of stressful environments.     

Reproduction in high altitude Aymara: physiological stress and fertility planning?

Reproductive characteristics at high altitude are described based on the reproductive histories of 720 Aymara women, collected in 1998 and 1999 in a group of twelve peasant communities at a mean altitude of 4000 m in the Bolivian Altiplano. The reproductive pattern is shaped by a late onset of childbearing, associated with a rather short reproductive span and large birth intervals. Environmental conditions could explain the particularly late age at menarche of rural girls compared with their urban counterparts, whereas the age at first birth is likely to be under cultural control. The short reproductive span appears to result from a large mean interval between last birth and menopause, which is essentially determined by cultural decisions. The birth intervals, which are longer than in many traditional societies, could be the result of a slower restoration of postpartum fecundability induced by the hard way of life inherent in the Altiplano (including poor sanitary and nutritional conditions and high workload), perhaps aggravated by hypoxia. However, a secular trend in fertility is perceptible, towards earlier menarche, earlier age at first birth, increasing reproductive span and a slight increase in live births and surviving offspring, which is probably the result of a slow improvement in living conditions. The existence of birth control on the one hand, and a total fertility rate averaging six live births among the couples who do not practise contraception on the other, are other arguments against the hypothesis of a low natural fecundity in these Aymara groups.     

Menarche and father absence in a national probability sample

The relation between women's timing of menarche and father absence was examined in a national probability sample of Great Britain (NATSAL 2000; N>5000). Current body mass index (as a proxy for childhood weight) was examined as a potential mediator of this relationship, along with the potential moderating role that siblings (e.g. number of older brothers) had on this relationship. As in a number of previous studies, an absent father (but not an absent mother) during childhood predicted an earlier age of puberty (i.e. an early menarche). There was no evidence that weight mediated this relationship or that siblings moderated it. Both a lower body mass index and more siblings (e.g. more younger sisters and brothers) were independent predictors of a later timing of puberty. The results confirm that certain psychosocial factors (i.e. father absence; presence of siblings) may affect the timing of sexual maturation in adolescent girls.     

Father absence predicts age at sexual maturity and reproductive timing in British men

Despite the widespread assumption that paternal investment is substantial in our species, previous studies have shown mixed results in relation to the impact of fathers on both offspring survival and reproductive outcomes. Using data from a large representative sample of British men, we tested whether father absence is associated with the timing of reproduction-related events among boys, while controlling for various cues denoting early childhood adversity. We further tested whether the loss of the father at different childhood stages matters, so as to assess whether early life is the most important period or if effects can be seen during later childhood. The results show that father absence before age seven is associated with early reproduction, while father absence between ages 11 and 16 only is associated with delayed voice-breaking (a proxy for puberty), even after adjusting for other factors denoting childhood adversity. We conclude that fathers do exert an influence on male reproductive outcomes, independently of other childhood adversities and that these effects are sensitive to the timing of father absence.     

Premarital childbearing in northwest Kenya: challenging the concept of illegitimacy

A number of African countries, including Kenya, have experienced a marked rise in births among unmarried women. In Western countries, reproduction outside of marriage is assumed to be illegitimate and a social problem. One hypothesis used to explain the increasing incidence of premarital fertility in Africa is a breakdown of traditional social controls by the extended family over the sexual behavior of adolescents. A competing hypothesis suggests that unmarried women use sexual relations to achieve goals such as marriage. Among Turkana pastoralists of northwest Kenya, we find a pattern of premarital birth that fits either hypothesis only loosely. Premarital fertility among the Turkana is both widespread and culturally acceptable, with over 30 per cent of women having at least one child prior to marriage. Although women with premarital births initiate childbearing on average one year earlier than women with only marital births, women's marital status does not influence the length of the interval between first and second births. Marriage among the Turkana is not a social trigger for the onset and continuation of reproduction or a means to legitimate reproduction. Marital status of the parents simply determines the custody of a child. In a premarital birth, the father pays a set fee to the mother's family, and the custody of the child remains permanently with the mother's family. If the parents later marry, the father must purchase custody of the child by another fee at that time. Since the Turkana have experienced few effects of modernization, the existence of such a practice suggests that cultural factors must be taken into account before assessing premarital fertility in Africa as a social problem.