Paternity confidence and social obligations explain men's allocations to romantic partners in an experimental giving game

Paternal care in humans is facultative, with investment decisions responsive to socioecological context. In particular, paternity confidence is thought to have a significant impact on men's provisioning. However, various aspects of the relationship a man has with his partner can also influence the way he provides for his children. Previous papers have tended to focus either on these kinds of relationship dynamics or on the impact of paternity confidence. However, these categories are often intertwined and parsing their contributions can be conceptually and methodologically difficult. To better understand how paternity confidence and relationship dynamics impact men's investment decisions, we used a series of pictorial vignettes to assess the resource allocation strategies of Himba men. We focus on three traits: mate fidelity, partner type (marital or non-marital), and relationship status (current or former). Results suggest that men prioritize mate fidelity and current reproductive partners in investment decisions, but social obligations to past and current partners and the presence of other male investors also influence decisions. Himba men appear to be balancing social norms related to marriage and fatherhood with individually-driven incentives to invest in current and more faithful partners.     

Establishment of Legal Paternity for Children of Unmarried American Women

The establishment of a legal father for children of unmarried parents reflects both high paternity confidence and male willingness to commit to paternal investment. Whether an unmarried man voluntarily acknowledges paternity after a child is born has important consequences for both the mother and child. This paper brings to bear a life history perspective on paternity establishment, noting that men face trade-offs between mating and parental effort and that women will adjust their investment in children based on expected male investment. I predict that paternity establishment will be more likely when the mother has high socioeconomic status, when maternal health is good, and when the child is male, low parity, or a singleton (versus multiple) birth. I further predict that establishment of paternity will be associated with increased maternal investment in offspring, resulting in healthier babies with higher birthweights who are more likely to be breastfed. These predictions are tested using data on 5.4 million births in the United States from 2009 through 2013. Overall the results are consistent with the hypothesis that the trade-offs men face between reproductive and parental investment influence whether men voluntarily acknowledge paternity when a child is born.     

Men’s reproductive investment decisions

Using questionnaire data completed by 170 men, we examine variation in paternal investment in relation to the trade-off between mating and parenting. We found that as men’s self-perceived mate value increases, so does their mating effort, and in turn, as mating effort increases, paternal investment decreases. This study also simultaneously examined the influence on parental investment of men’s mating effort, men’s perception of their mates’ fidelity, and their perceived resemblance to their offspring. All predicted investment. The predictors of investment are also tested independently for men who are still in a relationship with the mother of their children and those that are separated from her. Finally we examine how self-perceived mate value affects how men respond to variation in paternity confidence. Men with a self-perceived low mate value were less likely to respond to lowered mate fidelity by reducing their parental investment compared with men with a self-perceived high mate value.     

Infidelity,jealousy, and wife abuse among Tsimane forager–farmers: testing evolutionary hypotheses of marital conflict

The role of men's jealousy over a wife's infidelity in precipitating marital conflict and wife abuse is well documented. The role of women's jealousy over a husband's infidelity has received little attention, which is puzzling given high potential costs to women of withdrawal of paternal investment. We address this gap by investigating marital conflict and wife abuse among Tsimane forager–farmers of Bolivia. We test predictions derived from male jealousy and paternal disinvestment hypotheses, which consider threats and consequences of infidelity by women (male jealousy hypothesis) and men (paternal disinvestment hypothesis). The paternal disinvestment hypothesis proposes that wife abuse is employed by husbands to limit wives' mate retention effort and maintain men's opportunities to pursue extrapair sexual relationships. Interviews were conducted among husbands and wives in the same marriages using a combination of open-ended and structured items. Spouses agree that the most frequently reported type of marital argument is women's jealousy over a husband's infidelity (N=266 arguments). Roughly 60% of abusive events occurred during arguments over men's diversion of household resources (N=124 abusive events). In multivariate analyses, likelihood of wife abuse is greater in marriages where husbands have affairs, where wives are younger, and where spouses spend more time apart (N=60 husbands, 71 wives). While we find strong support for both male jealousy and paternal disinvestment hypotheses, it is men's infidelity, not women's, that precipitates most instances of marital conflict and wife abuse. We conclude that men's aggression towards their wives facilitates men's diversion of family resources for their selfish interests.     

The goals of direct paternal care among a South Amerindian population

Human males are remarkable among mammals in the level of investment they provide to their wives and children. However, there has been debate as to the degree to which men actually invest and through which fitness pathways the benefits of familial investment are realized. Much of the previous research exploring these issues has focused on men's roles as providers, but few have explored correlates of men's direct parental care. Although this is reasonable given men's parental emphasis on provisioning, the providing of direct care is more straightforward with a clear provider and recipient and little ambiguity as to the care‐giver's intent. Here, we explore contextual correlates of men's direct care among the Tsimane of Bolivia to determine the extent to which such care is patterned to enhance its effectiveness in increasing child wellbeing and the efficient functioning of the family. We also explore whether Tsimane fathers provide care in ways that enhance the positive effect it has on the wife's perception of the care provider. Overall, we find that Tsimane men appear responsive to the needs of children and the family, but show that there is little evidence that men respond to factors expected to increase the impact that men's care has on their reputations with their wives. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.     

Male facial attractiveness,perceived personality,and child-directed speech

This study investigated associations between men's facial attractiveness, perceived personality, attitudes towards children, and the quality of their child-directed (CD) speech. Sixty-three males were photographed and completed a brief questionnaire concerning their family background and attitudes towards children. They then performed a task in which they gave directions to (imaginary) adults and children. Analyses of the acoustic properties of speech produced under each condition were performed in order to determine the extent to which individual men changed their speech to accommodate a child listener (i.e., exhibited CD speech). The men's faces were rated by 59 female participants, who assessed perceived prosociality, masculinity, health, and short- and long-term attractiveness. Although women's ratings of attractiveness and prosociality were related to men's self-reported liking for children, they were negatively correlated to men's use of CD speech (i.e., less attractive men used more features of CD speech when addressing an imaginary child). These findings are discussed in the context of halo effects and strategic pluralism in male mating behaviors.     

Reactions to children's faces: Resemblance affects males more than females

Since cuckoldry risk is asymmetrical, we hypothesized that parental investment would be more affected by paternal than maternal resemblance. To test this hypothesis, we asked subjects hypothetical questions about investing in children under conditions in which their faces or those of other people had been morphed with photographs of children. Males were more likely to choose a face they had been morphed with as the most attractive, the child they were most likely to adopt, the child they would like to spend the most time with, the child they would spend US$50 on, and the child they would least resent having to pay child support for. Reactions to children's faces by females were much less affected by resemblance.     

Demographic correlates of paternity confidence and pregnancy outcomes among Albuquerque men

We examine the demographic correlates of paternity confidence, or men's assessment of the likelihood that they are the genetic father of a particular child. Evolutionary theory predicts that men will provide less parental investment for putative genetic offspring who are unlikely to be their actual offspring, but confidence of paternity has not been as extensively examined as its importance would merit. Using self-reported data on paternity confidence in 3,360 pregnancies reported by men living in Albuquerque, New Mexico, we find that low paternity confidence is more common among unmarried couples and for unplanned pregnancies. We also find that men are more likely not to state paternity confidence (i.e., they refuse to answer the question) if a pregnancy is unplanned. We additionally examine the pregnancy outcomes associated with confidence of paternity. We find that low paternity confidence pregnancies are significantly more likely to be aborted, and pregnancies for which paternity confidence is unstated are more likely to be aborted or to miscarry. Both abortion and miscarriage are associated with unmarried couples, with unplanned pregnancies, and with couples who have fewer children together.     

Paternity cues and mating opportunities: what makes fathers good?

Human males provide facultative paternal investment to their offspring; that is, the male care is not necessary for the survival of his offspring. It is expected that the degree of male investment (1) increases with growing paternity certainty, (2) increases when investment increases the survival and later reproductive prospect of offspring and (3) declines when there are opportunities to mate with multiple females. Using a large sample of adult offspring and their fathers (n = 245), we first investigated the role of two factors possibly involved in the assessment of paternity and subsequently regulating the level of paternal investment: (a) father–child facial resemblance and (b) assortative mating for eye colour. Second, because mating opportunities are inversely related to paternal investment, we also investigated how male facial attractiveness (a cue of mate opportunities) correlates with paternal investment. In line with paternal investment theory, male investment positively correlated with offspring facial resemblance. However, paternal investment were neither higher among blue-eyed couples, nor there were preferences of blue-eyed men to marry with blue-eyed women. Moreover, father facial attractiveness was unrelated to paternal investment. These results indicate that resemblance between offspring and their fathers still plays an important role in paternal investment decision later in offspring’s life.     

Genetic relatedness to sisters' children has been underestimated

Males of many species help in the care and provisioning of offspring, and these investments often correlate with genetic relatedness. For example, many human males invest in the children of sisters, and this is especially so where men are less likely to share genes with children of wives. Although this makes qualitative sense, it has been difficult to support quantitatively. The prevailing model predicts investment in children of sisters only when paternity confidence falls below 0.268. This value is often seen as too low to be credible; so investment in sisters'' children represents an unsolved problem. I show here that the prevailing model rests on a series of restrictive assumptions that underestimate relatedness to sisters'' children. For this reason, it understates the fitness payoff to men who invest in these children. This effect can be substantial, especially in societies with low confidence in paternity. But this effect cannot be estimated solely from confidence in paternity. One must also estimate the probability that two siblings share the same father.     

Confidence of paternity and paternal care: covariation revealed through the experimental manipulation of the mating system in the beetle Onthophagus taurus

Theoretical models of paternal care predict that facultative reductions in male care may occur under certain conditions. One important parameter that has been shown to influence the outcome of these models is a male's confidence of paternity. In this study, we tested whether the amount of care provided by horned males in the dimorphic beetle, Onthophagus taurus, varied with his confidence of paternity. Male care results in an increased weight of dung provided in the brood masses produced by the pair. Using the sterile male technique we showed that a horned male's paternity declined with the number of sneak males in the population. The relationship was nonlinear, with paternity declining most rapidly between a frequency of one and three sneaks, and stabilizing thereafter at about 50%. A horned male's paternity was directly related to the number of copulations with the female, relative to the number of copulations achieved by sneaks. Horned males were shown to reduce their care in relation to their declining paternity. Video analysis demonstrated that reductions in male care occurred through a combination of male desertion and a trade‐off between caring and paternity assurance behaviours. The number of fights with sneak males was negatively related to the amount of care provided by a horned male. These results suggest that by gauging his expected paternity through the number of fights with sneaks, a horned male is able to assess his paternity and reduce his investment accordingly. Our data thus provide strong empirical support for the proposed link between paternity and paternal care.     

Exploring the Relation of Harsh Parental Discipline with Child Emotional and Behavioral Problems by Using Multiple Informants. The Generation R Study

Parental harsh disciplining, like corporal punishment, has consistently been associated with adverse mental health outcomes in children. It remains a challenge to accurately assess the consequences of harsh discipline, as researchers and clinicians generally rely on parent report of young children''s problem behaviors. If parents rate their parenting styles and their child''s behavior this may bias results. The use of child self-report on problem behaviors is not common but may provide extra information about the relation of harsh parental discipline and problem behavior. We examined the independent contribution of young children''s self-report above parental report of emotional and behavioral problems in a study of maternal and paternal harsh discipline in a birth cohort. Maternal and paternal harsh discipline predicted both parent reported behavioral and parent reported emotional problems, but only child reported behavioral problems. Associations were not explained by pre-existing behavioral problems at age 3. Importantly, the association with child reported outcomes was independent from parent reported problem behavior. These results suggest that young children''s self-reports of behavioral problems provide unique information on the effects of harsh parental discipline. Inclusion of child self-reports can therefore help estimate the effects of harsh parental discipline more accurately.     

Male burying beetles extend,not reduce,parental care duration when reproductive competition is high

Male parents spend less time caring than females in many species with biparental care. The traditional explanation for this pattern is that males have lower confidence of parentage, so they desert earlier in favour of pursuing other mating opportunities. However, one recent alternative hypothesis is that prolonged male parental care might also evolve if staying to care actively improves paternity. If this is the case, an increase in reproductive competition should be associated with increased paternal care. To test this prediction, we manipulated the level of reproductive competition experienced by burying beetles, Nicrophorus vespilloides (Herbst, 1783). We found that caregiving males stayed for longer and mated more frequently with their partner when reproductive competition was greater. Reproductive productivity did not increase when males extended care. Our findings provide support for the increased paternity hypothesis. Extended duration of parental care may be a male tactic both protecting investment (in the current brood) and maximizing paternity (in subsequent brood(s) via female stored sperm) even if this fails to maximize current reproductive productivity and creates conflict of interest with their mate via costs associated with increased mating frequency.     

Paternal Care by Genetic Fathers and Stepfathers I: Reports from Albuquerque Men

We present a biosocial model of human male parental care that allows male parental allocations to be influenced not only by changes in the fitness (welfare) of the recipient offspring, but also by their effects on the man's relationship with the child's mother. The model recognizes four classes of relationships between males and the children they parent: genetic offspring of current mates (combined relationship and parental effort), genetic offspring of previous mates (parental effort solely), step offspring of current mates (relationship effort solely), and stepchildren of previous mates (essentially no expected investment). We test the model using data on parental investments collected from adult males living in Albuquerque, New Mexico, U.S.A. Four measures of paternal investment are examined: the probability that a child attends college (2,191 offspring), the probability that a child who attends college receives money for it (N = 1,212), current financial expenditures on children (N = 635), and the amount of time per week that men spend with children ages 5 to 12 years (N = 2,589). The tests are consistent with a role for relationship effort in parental care: men invest more in the children of their current mates, even when coresidence with offspring is not a confounder.     

Paternal effort related to experimentally manipulated paternity of male collared flycatchers

The way that variation in paternity affects the optimal level of paternal effort has been a contentious issue, both in terms of theory and the empirical data needed to test competing theories. Clarification of the theoretical issues has led to the prediction that a reduction in paternal effort should only be expected when (i) there are substantial costs of paternal care and (ii) males have available some cue to their share of paternity in the current brood. Previous work on the collared flycatcher, Ficedula albicollis, has shown that the first condition is supported because of trade-offs between paternal effort and secondary sexual character size. We carried out experimental manipulations of pairs of collared flycatchers (temporary male removal), which were effective in causing variation in paternity in the current brood. Male responses to these manipulations were studied by quantifying levels of paternal care. All males reared nestlings cross-fostered from non-experimental nests at the egg stage, thus ruling out the possibility that they responded to direct cues about paternity. The timing of male removal predicted the male''s share of paternity, suggesting that males had a clear cue to their share of paternity, thereby fulfilling the second condition. As expected, the male''s share of care, and rate of provisioning, were positively related to his share of paternity. The suggestion that the timing of removal was the cue used by males to predict their share of paternity was supported, since after the influence of this variable was controlled, there was no longer any relationship between paternity and paternal care. These data provide qualitative support for optimality models of paternal care in relation to certainty of paternity, and suggest that quantitative tests of the models are possible in well-characterized systems.     

The effect of paternal investment on female fertility intention in South Korea

Life history theory views reproduction as an outcome of resource allocation. The allocation of resources such as parental investments of time, energy and material resources involves trade-offs between number of offspring and timing of reproduction. Within the framework of mammalian parental investment, the outstanding feature of human reproduction is the high level of paternal care. Although empirical evidence suggests that human paternal investment may have evolved as a reproductive strategy to reduce infant and child mortality rates, the effects of actual paternal investment, including allocating time to child care, on female reproductive decisions have received relatively little attention. We examined the trade-off from two perspectives using a representative sample of married South Korean women aged 20–44 in 2005 (n=977). First, paternal investment in domestic labor, including child care and housework, was expected to be associated with women's preference regarding future reproduction. Second, relative paternal investment was expected to increase women's preference for future reproduction, especially among employed women. We found that increased paternal investment in child care and housework remarkably enhanced women's intention to have a second child, especially among employed women. In addition, although family members provide a low percentage of child care in South Korea, such help is likely to be a useful resource for second childbirth among employed women. Somewhat expectedly, older age and longer time since first birth had negative effects on women's second-child intention. There is growing evidence that, in the lowest fertility societies, paternal investment may be an essential resource for promoting future reproductive behavior of women, especially employed women.     

Human male mating strategies: II. Moral codes of “quality” and “quantity” strategists

Men following quality and quantity strategies (pair bond with paternal investment/short-term sexual bonds) should have different, self-serving moral codes. If so, the different strategists should rate dating behaviors differently on ethical (honest and exploitative) and usage (by quality and quantity courters) scales. Quality strategists, who use honest advertisement, should promote their honest behavior by sharp distinctions between what is honest and exploitative and between what men like themselves and others (quantity strategists) do. Quantity strategists, who may exploit (e.g., verbal or physical coercion), should blur these distinctions. Their interests are served by the belief that all men are alike and not morally distinguishable. The companion study obtained men's ratings of quality-strategy behaviors (honest) and quantity-strategy behaviors (exploitative) on ethical and usage scales. Correlations were obtained between those ratings and the same men's scores on bipolar dimensions distinguishing quality from quantity strategists: sexual history, adult characteristics associated with female mate preference, and certain childhood experiences. The correlations supported the hypotheses with two exceptions. First, socioeconomic status and endorsement of a foraging tactic (leave if sexual relations do not start quickly) predicted ratings for quality-strategy behaviors, but did not predict ratings for quantity-strategy behaviors. Sexual history items and childhood experiences related to perceptions of relationships predicted only the ratings for quantity-strategy behaviors. Second, ratings of the lack of honesty in exploitative behavior and its lack of usage by quality courters did not distinguish the strategists. Three conclusions followed. One, there are two kinds of quantity strategists: commodifiers who trade resources for sex and predators who exploit. Two, quantity strategists are mixed strategists while some men follow only a quality strategy. Three, quantity strategists deceive themselves about the exploitative character of their behavior. The data fit evolutionary analyses of human morality and, with a few exceptions, current views of contextual factors governing adoption of different reproductive strategies.     

Religious cognition down-regulates sexually selected,characteristically male behaviors in men,but not in women

Men are typically stronger, riskier, “showier,” and more impulsive than women. According to sexual selection theory, such behaviors may have enhanced reproductive fitness for ancestral human males. However, such behaviors are facultative, and the mechanisms that cause them respond to social and environmental cues that indicate whether outlays of strength, risk-taking, showing off, or impulsivity are likely to lead to payoffs in any given instance. Recent research based on the Reproductive Religiosity Model suggests that, in contemporary Western societies, religious beliefs and institutions are differentially espoused and promulgated by restricted sexual strategists (whose reproductive strategies focus on high fertility, monogamy, and high parental care) to limit the exercise of unrestricted sexuality, which threatens the viability of restricted sexual strategies (e.g., by reducing paternity certainty and male parental investment). On this basis, we hypothesized that experimental manipulations of religious cognition would reduce men's impulsivity and motivation to demonstrate their physical prowess. Supporting this hypothesis, three experiments revealed that priming participants with religious concepts (i.e., participants wrote essays about religion, read an essay supporting the existence of an afterlife, or were implicitly exposed to religious words) reduced men's (but not women's) impulsivity with money and their physical endurance on a hand grip task. The primes affected men's behaviors irrespectively of men's scores on a self-report measure of religious commitment.     

Short-term changes in fathers' hormones during father–child play: Impacts of paternal attitudes and experience

Hormonal differences between fathers and non-fathers may reflect an effect of paternal care on hormones. However, few studies have evaluated the hormonal responses of fathers after interacting with their offspring. Here we report results of a 30-minute in-home experiment in which Filipino fathers played with their toddlers and consider whether paternal experience and men's perceptions of themselves as fathers affect hormonal changes. Fathers provided saliva and dried blood spot samples at baseline (B) and 30 (P30) and 60 (P60, saliva only) minutes after the interaction. We tested whether testosterone (T), cortisol (CORT), and prolactin (PRL) shifted after the intervention. In the total sample, T did not vary over the study period, while CORT declined from B to P30 and P60, and PRL also declined from B to P30. Fathers who spent more time in daily caregiving and men who thought their spouses evaluated them positively as parental caregivers experienced a larger decline in PRL (B to P30) compared to other fathers. First-time fathers also had larger declines in PRL compared to experienced fathers. Experienced fathers also showed a greater decline in CORT (B to P60) compared to first-time fathers. These results suggest that males' paternal experience and age of offspring affect hormonal responses to father–child play and that there is a psychobiological connection between men's perceptions of themselves as fathers and their hormonal responsivity to childcare.