The effect of infant fetal alcohol syndrome facial features on adoption preference

Infant facial characteristics may affect discriminative parental solicitude because they convey information about the health of the offspring. We examined the effect of Fetal Alcohol Syndrome (FAS) infant facial characteristics on hypothetical adoption preferences, ratings of attractiveness, and ratings of health. As expected, potential parents were more likely to adopt “normal” infants, and they rated the FAS infants as less attractive and less healthy. Cuteness/attractiveness was the best predictor of adoption likelihood. This study formed part of the first author’s undergraduate honors thesis at Queen’s University conducted under the supervision of the third author. This research was supported by an Ontario Mental Health Foundation Senior Research Fellowship and a research contract from the Kingston Providence Continuing Care Centre to the third author. Katherine L. Waller is a Ph.D. candidate in psychology at Queen’s University. Her research focuses on health psychology and behavior in close relationships. Anthony Volk is a Ph.D. candidate in psychology at Queen’s University. His research focuses on evolutionary psychology and parental investment. Vernon L. Quinsey is a professor of psychology and psychiatry at Queen’s University. His research focuses on forensic and evolutionary psychology.     

The reward value of infant facial cuteness tracks within-subject changes in women's salivary testosterone

“Baby schema” refers to infant characteristics, such as facial cues, that positively influence cuteness perceptions and trigger caregiving and protective behaviors in adults. Current models of hormonal regulation of parenting behaviors address how hormones may modulate protective behaviors and nurturance, but not how hormones may modulate responses to infant cuteness. To explore this issue, we investigated possible relationships between the reward value of infant facial cuteness and within-woman changes in testosterone, estradiol, and progesterone levels. Multilevel modeling of these data showed that infant cuteness was more rewarding when women's salivary testosterone levels were high. Moreover, this within-woman effect of testosterone was independent of the possible effects of estradiol and progesterone and was not simply a consequence of changes in women's cuteness perceptions. These results suggest that testosterone may modulate differential responses to infant facial cuteness, potentially revealing a new route through which testosterone shapes selective allocation of parental resources.     

Female and male responses to cuteness,age and emotion in infant faces

Neonatal features in the newborn are thought to trigger parental care, the most fundamental prosocial behaviour. The underlying mechanisms that release parental care have not yet been resolved. Here we report sex differences in the ability to discriminate cues to cuteness despite equivalence in the capability to discriminate age and facial expression. These differences become apparent in a task where adults were asked to choose the cuter of two babies. While women could reliably choose the cuter infant, men had more difficulty in doing so. When showing the exact same face pairs but asking to choose the younger or the happier baby, there was no sex difference. These results suggest that the sex difference in the ability to discriminate cues to cuteness in infants underlies female-specific emotive responses. We argue that this reactivity expressed by women evolved to ensure that a female allocates her caretaking resources to her youngest offspring while it needs mothering care.     

Children aged 7–9 prefer cuteness in baby faces,and femininity in women's faces

Infant facial features are typically perceived as “cute,” provoking caretaking behaviours. Previous research has focused on adults' perceptions of baby cuteness, and examined how these perceptions are influenced by events of the adult reproductive lifespan, such as ovulation and menopause. However, globally, individuals of all ages, including pre-pubertal children, provide notable proportions of infant care. In this study, we recruited participants in and around northern England, and tested 330 adults and 65 children aged 7–9 using a forced-choice paradigm to assess preferences for infant facial cuteness in two stimulus sets and (as a control task) preferences for femininity in women's faces. We analysed the data with Hierarchical Bayesian Regression Models. The adults and children successfully identified infants who had been manipulated to appear cuter, although children's performance was poorer than adults' performance, and children reliably identified infant cuteness in only one of the two infant stimuli sets. Children chose the feminised over masculinised women's faces as more attractive, although again their performance was poorer than adults' performance. There was evidence for a female advantage in the tasks: girls performed better than boys when assessing the woman stimuli and one of the infant stimulus sets, and women performed better than men when assessing one of the infant stimulus sets. There was no evidence that cuteness judgements differed depending upon exposure to infants (children with siblings aged 0–2; adults with a baby caregiving role), or depending upon being just younger or older than the average age of menopause. Children and grandparents provide notable portions of infant caretaking globally, and cuteness perceptions could direct appropriate caregiving behaviour in these age groups, as well as in adults of reproductive age.     

Reported maternal tendencies predict the reward value of infant facial cuteness,but not cuteness detection

The factors that contribute to individual differences in the reward value of cute infant facial characteristics are poorly understood. Here we show that the effect of cuteness on a behavioural measure of the reward value of infant faces is greater among women reporting strong maternal tendencies. By contrast, maternal tendencies did not predict women''s subjective ratings of the cuteness of these infant faces. These results show, for the first time, that the reward value of infant facial cuteness is greater among women who report being more interested in interacting with infants, implicating maternal tendencies in individual differences in the reward value of infant cuteness. Moreover, our results indicate that the relationship between maternal tendencies and the reward value of infant facial cuteness is not due to individual differences in women''s ability to detect infant cuteness. This latter result suggests that individual differences in the reward value of infant cuteness are not simply a by-product of low-cost, functionless biases in the visual system.     

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.     

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.     

Adults' responses to infants varying in perceived cuteness

The effects of perceived cuteness of infant photographs on the behaviour of young adults was investigated. Looking, facial muscle activity, and skin conductance were measured during individual presentations of the photographs, whereas only looking was measured during paired presentations. Both measures of looking time were significantly affected by the perceived cuteness of infant photographs, with infants ranked as most cute looked at longest and those ranked least cute looked at for the shortest length of time. Increased facial muscle activity previously associated with pleasant or happy facial expressions was associated with presentations of infant photographs but was not related to perceived cuteness. A second experiment indicated that increased facial muscle activity was specific to infant photographs. Adult responses to infant physical appearance appear to be regulated by two mechanisms: an initial positive response to “babyishness”, reflected by increased facial zygomaticus muscle activity, and an individual cognitive preference response to “cuteness”, reflected by differential looking times.     

Development of preference for baby faces across species in humans (<Emphasis Type="Italic">Homo sapiens</Emphasis>)

Previous studies have revealed that there is a close relationship between the strength of an infant’s baby schema and the degree of its perceived cuteness. The present study investigated the development of preference for baby schema in humans by examining the recognition of the cuteness of baby faces; two studies were conducted to examine whether children’s evaluation of cuteness differed from that of adults. Facial photographs not only of humans (Homo sapiens), but a chimpanzee (Pan troglodytes), rabbits (Oryctolagus cuniculus), dogs (Canis familiaris) and cats (Felis sylvestris catus) at different ages were used as stimuli. The volunteers were requested to rank these photographs in order of cuteness. Study 1 suggested that there was a range of period during which adults perceived the faces of these five species to be the cutest. Study 2 indicated that children’s judgment of cuteness closely corresponded to that of the adults. In conclusion, the preference for baby schema is observed in humans even before they get to be sexually mature enough to reproduce. Childhood preference for baby schema might be the basis of social learning, including caretaking behaviors.     

Abnormal births and other “ill omens”

We summarize the ethnographic literature illustrating that “abnormal birth” circumstances and “ill omens” operate as cues to terminate parental investment. A review of the medical literature provides evidence to support our assertion that ill omens serve as markers of biological conditions that will threaten the survival of infants. Daly and Wilson (1984) tested the prediction that children of demonstrably poor phenotypic quality will be common victims of infanticide. We take this hypothesis one stage further and argue that some children will be poor vehicles for parental investment yet are not of demonstrably poor quality at birth. We conclude that when people dispose of infants due to “superstitious beliefs” they are pursuing an adaptive strategy in eliminating infants who are poor vehicles for parental investment. Catherine Hill lectures in biological anthropology/human sciences at Durham University’s University College, Stockton. She trained in biological anthropology at University College, London. Her current research interests include human and nonhuman primate socioecology and human resource ecology and development issues. Helen Ball lectures in biological anthropology/human sciences at Durham University’s University College, Stockton. She trained in biological anthropology at the University of Massachusetts at Amherst. Her current research interests include nonhuman primate behavior and socioecology, reproductive biology, and evolutionary issues.     

Cues of parental investment as a factor in attractiveness

One prediction derived from parental investment theory is that women will be more attentive than men are to cues of a prospective mate's dispositions to invest in children. Research with 1793 Internet participants, representing a diverse population sample, found that (a) women tend to be generally more critical than men are in their evaluations of potential mates, but not potential friends or neighbors, and (b) cues of a positive disposition towards parental investment (DPI) have a positive influence on female evaluations of the attractiveness of males. This latter effect, however, is less domain-specific than previous research [La Cerra, M. M. (1995). Evolved mate preferences in women: Psychological adaptations for assessing a man's willingness to invest in offspring (doctoral dissertation, University of California, Santa Barbara). Dissertation Abstracts International: Section B: the Sciences & Engineering Mar, 55(9-B), 4149] indicated; it is not limited to mating contexts and to cues focusing on parental investment. In fact, much of the sex difference appears to be due to indifference by males towards cues of female DPI. A second study further clarified that the previous findings were not due solely to the Internet methodology or the immediate accessibility of images being evaluated.     

The life histories of American stepfathers in evolutionary perspective

This paper presents an analysis of the characteristics of men who become stepfathers, and their subsequent fertility patterns and lifetime reproductive success. Because women who already have children are ranked lower in the marriage market than women without children, men who marry women with children (e.g., stepfathers) are likely to have lower rankings in the marriage market as well. Using retrospective fertility and marital histories from the Panel Study of Income Dynamics (PSID), I show that men who become stepfathers have lower levels of education, less income, and are more likely to have been divorced before and to already have children, all characteristics that lower their rankings in the marriage market. Men with one or two stepchildren are just as likely to have children within a marriage as non-stepfathers, although men with three stepchildren show decreased fertility. Among men age 45 and older, stepfathers have lower lifetime fertility than non-stepfathers, although the difference disappears when men’s age at first marriage is controlled for. Additionally, stepfathers have significantly higher fertility than men who never marry. The results suggest that some men become stepfathers to procure mates and fertility benefits that they would otherwise have been unlikely to obtain; for these men, raising other men’s children serves as a form of mating effort. Preliminary versions of this paper were presented at the Evolution and Human Adaptation Program at the University of Michigan, and the Human Behavior and Evolution Society’s annual meeting at Amherst. Kermyt G. Anderson received his Ph.D. in anthropology from the University of New Mexico in 1999. He is currently a Mellon Postdoctoral Research Fellow at the Population Studies Center of the Institute for Social Research at the University of Michigan. His current research examines the relationship between family structure, parental investment, and children’s educational and employment outcomes in South Africa.     

Populational differences in attractiveness judgements of male and female faces: Comparing British and Jamaican samples

In the UK and Japan, both men and women prefer somewhat feminised opposite-sex faces, especially when choosing a long-term partner. Such faces are perceived as more honest, caring, and sensitive; traits that may be associated with successful male parental investment. By contrast, women prefer less feminised faces for short-term relationships and when they are near ovulation. As genetic quality may be associated with facial masculinity, women may ‘trade-off’ cues between genetic quality and paternal investment in potential partners. No analogous trade-off has been suggested to influence men's preferences, as both attributions of prosociality and potential cues to biological quality are associated with facial femininity in female faces. Ecological and cultural factors may influence the balance of trade-offs leading to populational differences in preferences. We predicted that Jamaican women would prefer more masculine faces than British women do because parasite load is higher in Jamaica, medical care less common (historically and currently), and male parental investment less pronounced. Male preferences, however, were predicted to vary less cross-culturally, as no trade-off has been identified in female facial characteristics. We constructed masculinised and feminised digital male and female face stimuli of three populations (Jamaican, Japanese, and British) and presented them to men and women in Jamaica and in Britain. The results demonstrated that Jamaican women preferred more masculine male faces than their British counterparts did. Jamaican men tended to prefer more masculine female faces than did British men did, but this effect was complicated by an interaction suggesting that more feminised faces were preferred within culture.     

Prolactin responses to infant cues in men and women: effects of parental experience and recent infant contact

We used a longitudinal design to test whether parental experience differentially affects the development of prolactin responses to infant cues in men and women. Couples provided two blood samples at three tests, one test just before their babies were born, and two tests during the early postnatal period (n=21). Nine couples repeated the tests near the birth of their second babies. In the 30 min between the two samples, couples listened to recorded infant cries at the prenatal test and held their baby (fathers) or a doll (mothers) at the postnatal tests. Blood samples were analyzed for prolactin concentrations. Prolactin values were then related to sex and parity differences as well as to questionnaire data concerning emotional responses to infant cries and previous infant contact. We found that (1) prior to the birth of both the first and second babies, women's prolactin concentrations increased after exposure to infant stimuli, whereas men's prolactin concentrations decreased; postnatal sex differences varied with parity; (2) women's prolactin reactivity did not change significantly with parental experience; (3) the same men's prolactin concentrations decreased after holding their first newborns but increased after holding their second newborns; this change was not gradual or permanent; (4) men reporting concern after hearing recorded infant cries showed a different postnatal pattern of prolactin change after holding their babies than men not reporting concern; and (5) men who had little contact with their babies just prior to testing had a more positive prolactin response than men who had recently held their babies for longer periods. Although parental experience appears to affect men's prolactin responses, differences in reactivity were also related to patterns of recent infant contact and individual differences in responses to infant cues.     

The motivational salience of infant faces is similar for men and women

Infant facial features are thought to be powerful elicitors of caregiving behaviour. It has been widely assumed that men and women respond in different ways to those features, such as a large forehead and eyes and round protruding cheeks, colloquially described as 'cute'. We investigated experimentally potential differences using measures of both conscious appraisal ('liking') and behavioural responsivity ('wanting') to real world infant and adult faces in 71 non-parents. Overall, women gave significantly higher 'liking' ratings for infant faces (but not adult faces) compared to men. However, this difference was not seen in the 'wanting' task, where we measured the willingness of men and women to key-press to increase or decrease viewing duration of an infant face. Further analysis of sensitivity to cuteness, categorising infants by degree of infantile features, revealed that both men and women showed a graded significant increase in both positive attractiveness ratings and viewing times to the 'cutest' infants. We suggest that infant faces may have similar motivational salience to men and women, despite gender idiosyncrasies in their conscious appraisal.     

Does observed fertility maximize fitness among New Mexican men?

Our objective is to test an optimality model of human fertility that specifies the behavioral requirements for fitness maximization in order (a) to determine whether current behavior does maximize fitness and, if not, (b) to use the specific nature of the behavioral deviations from fitness maximization towards the development of models of evolved proximate mechanisms that may have maximized fitness in the past but lead to deviations under present conditions. To test the model we use data from a representative sample of 7,107 men living in Albuquerque, New Mexico, between 1990 and 1993. The model we test proposes that low fertility in modern settings maximizes number of grandchildren as a result of a trade-off between parental fertility and next generation fertility. Results do not show the optimization, although the data do reveal a trade-off between parental fertility and offspring education and income. We propose that two characteristics of modern economies have led to a period of sustained fertility reduction and to a corresponding lack of association between income and fertility. The first is the direct link between costs of investment and wage rates due to the forces of supply and demand for labor in competitive economies. The second is the increasing emphasis on cumulative knowledge, skills, and technologies in the production of resources. Together they produce historically novel conditions. These two features of modern economies may interact with evolved psychological and physiological mechanisms governing fertility and parental investment to produce behavior that maximizes the economic productivity of lineages at the expense of fitness. If cognitive processes evolved to track diminishing returns to parental investment and if physiological processes evolved to regulate fertility in response to nutritional state and patterns of breast feeding, we might expect non-adaptive responses when returns from parental investment do not diminish until extremely high levels are reached. With high economic payoffs from parental investment, people have begun to exercise cognitive regulation of fertility through contraception and family planning practices. Those cognitive processes maynot have evolved to handle fitness trade-offs between fertility and parental investment. A preliminary presentation of this data was published in R. I. M. Dunbar, ed.,Human Reproduction Decisions: Biological and Social Perspectives. New York: St. Martin’s Press, 1995. Support for the research project, “Male Fertility and Parenting in New Mexico,” began with two seed grants from the University of New Mexico’s Biomedical Research Grants Program, 1988 and 1989, and one from the University of New Mexico Research Allocations Committee, 1988. Further seed money as well as interim funding came from the William T. Grant Foundation (#89130589 and #91130501). The major support for the project came from the National Science Foundation from 1990 to 1993 (#BNS-9011723 and #DBS-911552). Both National Science Foundation grants included Research Experience for Undergraduates supplements. Hillard S. Kaplan is an Associate Professor of Anthropology at the University of New Mexico. His earlier research and publications focused on food sharing, time allocation, parental investment, and reproductive strategies among Ache hunter-gatherers in Paraguay, Machiguenga and Piro forager-horticulturalists in Peru, and villagers of several ethnicities in Botswana. New research and theory concern fertility, parental investment, and mating strategies in developed and developing nations. This research formulates a new theory of reproductive decision-making and the demographic transition, integrating human capital and parental investment theory in a synthesis of economic and evolutionary approaches. Jane B. Lancaster is a Professor of Anthropology at the University of New Mexico. Her research and publications are on human reproductive biology and behavior, especially human parental investment; women’s reproductive biology of pregnancy, lactation, and child-spacing; and male fertility and investment in children. Current research with Hillard S. Kaplan is on male life history strategies among a large sample of men in New Mexico. She has coedited three books on human parental investment:School-Age Pregnancy and Parenthood (with B. Hamburg),Parenting across the Life Span (with J. Altmann, A. Rossi, and L. Sherrod), andOffspring Abuse and Neglect (with R. Gelles). She is scientific editor of a quarterly journal,Human Nature: An Interdisciplinary, Biosocial Perspective published by Aldine de Gruyter. She is also a council member of the newly formed Human Behavior and Evolution Society. John A. Bock is Andrew W. Mellon Post-Doctoral Fellow in Epidemiology and Population Health at the National Centre for Epidemiology and Population Health, The Australian National University. His research focuses on the allocation of parental investment and the determinants of children’s activities, integrating aspects of economic and evolutionary theory. He has ongoing field research with Bantu and Bushmen agro-pastoralists and forager-horticulturalists in the Okavango Delta, Botswana. He is also collaborating with Lancaster and Kaplan on the determinants of progeny distribution and homosexuality among New Mexican men. Sara E. Johnson is a Ph.D. candidate at the University of New Mexico. Her major research trajectory focuses on trade-offs in life history characters. Her research experience includes participation in a study of variation in growth and development among children in a multi-ethnic community in the Okavango Delta, Botswana, in addition to her dissertation work on individual variation in growth and mortality among juvenile baboons. She is collaborating with Lancaster and Kaplan on the association between survival and fertility among Albuquerque men.     

The poetics of babytalk

Caretaker-infant attachment is a complex but well-recognized adaptation in humans. An early instance of (or precursor to) attachment behavior is the dyadic interaction between adults and infants of 6 to 24 weeks, commonly called "babytalk." Detailed analysis of 1 minute of spontaneous babytalk with an 8-week infant shows that the poetic texture of the mother’s speech—specifically its use of metrics, phonetics, and foregrounding—helps to shape and direct the baby’s attention, as it also coordinates the partners’ emotional communication. We hypothesize that the ability to respond to poetic features of language is present as early as the first few weeks of life and that this ability attunes cognitive and affective capacities in ways that provide a foundation for the skills at work in later aesthetic production and response. By linking developmental social processes with formal cognitive aspects of art, we challenge predominant views in evolutionary psychology that literary art is a superfluous byproduct of adaptive evolutionary mechanisms or primarily an ornament created by sexual selection. David S. Miall is Professor of English at the University of Alberta in Canada. He is the author of essays on British Romantic writers, empirical studies of readers’ responses to literature, hypertext and literary computing. Ellen Dissanayake is Visiting Scholar at the Walter Chapin Simpson Center for the Humanities, University of Washington. Her most recent book is Art and Intimacy: How the Arts Began (2000).     

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.