Physical attractiveness and reproductive success in humans: Evidence from the late 20 century United States

Eye-Tracking Insights into the Perception of Buttocks

BACKGROUND

Aesthetic enhancements to the buttock region have grown in demand due to media influence and evolving beauty standards. Using eye-tracking technology, we sought to uncover subconscious visual preferences regarding the buttock aesthetic. The objective of this investigation was to assess visual gaze patterns in assessing female buttocks among Caucasian and Asians through eye-tracking technology.

MATERIALS AND METHODS

67 participants viewed photographs of buttocks from various angles, and eye movements were analyzed using the Tobii Pro Nano eye-tracker.

RESULTS

Males fixated on the intergluteal cleft for 0.96 ± 1.1 s and the thigh gap for 0.07 ± 0.2 s; while, females fixated for 0.81 ± 0.9 s and 0.06 ± 0.2 s on the same regions, respectively. Significant gender differences were observed in the intergluteal cleft (p = 0.002) and upper lateral buttock (p < 0.001).

CONCLUSION

This study offers new insights into the observation of buttocks. The consistent attention toward the intergluteal cleft across demographics could be of potential significance in the aesthetic perception of buttocks. However, diverse gaze patterns also underscore the multifaceted nature of human attraction. These findings hold implications for plastic surgery, aesthetic medicine, and the sociocultural understanding of beauty. A deeper dive into aesthetic preferences is pivotal for a holistic understanding of human perceptions of attractive buttocks.

LEVEL OF EVIDENCE III

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Fatherhood timing and men's midlife earnings: A within-family study of Finnish cohorts born in 1938-50

Fathers tend to achieve higher earnings than childless men, but there is limited evidence on the associations between fatherhood timing and men's later earnings. Using a longitudinal census-based sample of Finnish men, including a subsample of brothers, we investigated fatherhood timing and men's midlife earnings using both between- and within-family models. Earnings around age 50 were lower among adolescent and young fathers than for men who became fathers at ages 25-29 or later, but these associations became negligible after accounting for measured confounders and unobserved familial confounding. Overall, our findings highlight the important roles of selection into early childbearing and into childlessness. At the population level, early fatherhood was associated with clear negative distributional shifts in fathers' midlife earnings. However, among all men, any influence of fatherhood timing on men's midlife earnings distribution paled in comparison with that of childlessness.

Effect of smile on facial attractiveness before and after orthodontic treatment in females with more attractive and less attractive facial background

INTRODUCTION

One of the goals of orthodontic treatment is to improve facial esthetics. This study aimed to determine the effect of smile on facial attractiveness before and after orthodontic treatment in females with "more attractive" and "less attractive" facial backgrounds. In addition, changes in facial attractiveness after orthodontic treatment were examined.

METHODS

Frontal rest and smile photographs of 60 female patients (mean age, 26.32 years) before and after orthodontic treatment were included in 4 separate online questionnaires. The link for each questionnaire was sent to 40 layperson raters (20 females, 20 males). They were asked to give a score from 0 to 100 on the basis of the visual analog scale for the attractiveness of each image. Then the data were collected and analyzed.

RESULTS

The mean score of the pretreatment smile was significantly smaller than the frontal rest view, and the difference was significantly greater in the "more attractive" group (P = 0.012). After treatment, the smiling view was significantly more attractive than the frontal rest view, and the difference was significantly greater in the "less attractive" group (P = 0.014). In addition, the attractiveness of both smiling and rest views increased significantly after orthodontic treatment, and these changes were significantly greater in the "more attractive" group (P <0.001 and P = 0.011).

CONCLUSIONS

An unesthetic pretreatment smile negatively impacted facial attractiveness, and orthodontic treatment significantly improved facial attractiveness. These negative and positive effects were greater in more attractive facial backgrounds.

Social and sexual consequences of facial femininity in a non-human primate

In humans, femininity shapes women's interactions with both genders, but its influence on animals remains unknown. Using 10 years of data on a wild primate, we developed an artificial intelligence-based method to estimate facial femininity from naturalistic portraits. Our method explains up to 30% of the variance in perceived femininity in humans, competing with classical methods using standardized pictures taken under laboratory conditions. We then showed that femininity estimated on 95 female mandrills significantly correlated with various socio-sexual behaviors. Unexpectedly, less feminine female mandrills were approached and aggressed more frequently by both sexes and received more male copulations, suggesting a positive valuation of masculinity attributes rather than a perception bias. This study contributes to understand the role of femininity on animal's sociality and offers a framework for non-invasive research on visual communication in behavioral ecology.

Beauty is only skin deep: An examination of physical attractiveness, attractive personality, and personal grooming on criminal justice outcomes

Research has found that physical attractiveness is related to a host of benefits across life outcomes. Within the field of criminal justice, physical attractiveness appears to afford individuals leniency at various decision points. This research, however, often fails to include measures of personal presentation beyond simply measuring physical attractiveness. The current study extends this line of research by investigating how physical attractiveness, personality attractiveness, and grooming are related to criminal justice processing decisions. Results from negative binomial and logistic regression analyses indicate that when assessed alone, physical attractiveness significantly decreased the odds of criminal behavior by 18 percent, arrest by 11 percent, conviction by 14 percent, and incarceration by 28 percent-controlling for race, age, and gender. When controlling for personality and grooming, however, physical attractiveness results in a 47 to 53 percent increase in the risk of experiencing these outcomes while having an attractive personality and being well-groomed significantly reduced such risk. These results highlight the importance of considering other factors of appearance and personal presentation when considering how attractiveness influences criminal justice outcomes.

To Enhance, or not to Enhance: The Situational Context Shapes Women's Intentions on Amount and Diligence of Makeup Application

Makeup is a tool that women use to shape their image and gain benefits in both inter- and intrasexual selection. As makeup enables the hiding or enhancing of facial features, it allows women to strategically shape impressions in a given context. It affects interpersonal perceptions, workplace impressions, and can attract romantic partners. However, research has primarily focused on examining everyday makeup use, although the amount and type of makeup can vary depending on the situation and the motivation to make an impression. In two studies, we investigated how the intended amount and application of makeup differ depending on various situational contexts. Specifically, in Study 1 (N = 533), we explored the everyday and party contexts, while in Study 2 (N = 400), we additionally introduced the contexts of mating and threat. The results show that: 1) women intend to put on more makeup in a more diligent way in party contexts compared to everyday contexts, 2) the intended diligence of makeup application is the highest in contexts were women expect an attractive man to be present, and the lowest when a threatening context is introduced, 3) these effects are partially or fully mediated by women's motivation to make an impression, and 4) neither sociosexual orientation nor appearance orientation significantly moderated the obtained effects. Our studies extend previous research on makeup application as an appearance-enhancing or worsening strategy by further investigating the signaling function of women's makeup and its strategic use in various situational contexts. We discuss the results from a functional evolutionary perspective.

Understanding the Impact of Aging on Attractiveness Using a Machine Learning Model of Facial Age Progression

Background: Advances in machine learning age progression technology offer the unique opportunity to better understand the public's perception on the aging face. Objective: To compare how observers perceive attractiveness and traditional gender traits in faces created with a machine learning model. Methods: Eight surveys were developed, each with 10 sets of photographs that were progressively aged with a machine learning model. Respondents rated attractiveness and masculinity or femininity of each photograph using a sliding scale (range: 0-100). Mean attractiveness scores were calculated and compared between men and women as well as between age groups. Results: A total of 315 respondents (51% men, 49% women) completed the survey. Accuracy of the facial age progression model was 85%. Females were considered significantly less attractive (-10.43, p < 0.01) and less feminine (-7.59, p < 0.01) per decade with the greatest drop over age 40 years. Male attractiveness and masculinity were relatively preserved until age 50 years where attractiveness scores were significantly lower (-5.45, p = 0.39). Conclusions: In this study, observers were found to perceive attractiveness at older ages differently between men and women.

Individual attractiveness preferences differentially modulate immediate and voluntary attention

Physical attractiveness plays a crucial role in mate choice for both men and women. This is reflected in visual attention: people immediately attend towards and look longer at attractive faces, especially when they are motivated to find a partner. However, previous studies did not incorporate real-life dating decisions. Here, we aimed to combine attentional tasks with individual attractiveness ratings and a real-life mate choice context, namely a speed-dating paradigm. We investigated whether heterosexual non-committed young adults showed biases in immediate and voluntary attention towards attractive faces and preferred dating partners. In line with previous research, we found considerable individual differences in individual attractiveness preferences. Furthermore, our results showed that men had a bias towards attractive faces and preferred dating partners in the immediate attention task, while results for women were mixed. In the voluntary attention task, however, both men and women had an attentional bias towards attractive faces and preferred dating partners. Our results suggest that individual attractiveness preferences are good predictors of especially voluntary attention. We discuss these findings from an evolutionary perspective and suggest directions for future research.

Facial attractiveness is only weakly linked to genome-wide heterozygosity

Introduction

It has been frequently suggested that overall genomic heterozygosity and, particularly, heterozygosity of loci on the so-called major histocompatibility complex (MHC), which is responsible for the recognition of foreign substances/ pathogens and the recognition of self and non-self, is associated with better health and better resistance to infections and parasites. It has further been speculated that such a potentially beneficial heterozygosity can be detected through body odor and facial attractiveness.

Methods

On the basis of genome wide SNP data (713,014 SNPs) of participants from the Wisconsin Longitudinal Study, we therefore investigated whether homozygosity either on the MHC (measured as inbreeding coefficient) or genome-wide (measured as runs of homozygosity and inbreeding coefficient) is associated with rated facial attractiveness.

Results

Although we found that the genome-wide average length of homozygous segments and the genome-wide inbreeding coefficient are significantly negatively associated with some measures of facial attractiveness, if corrected for multiple testing, any significant association was no longer formally significant after correction. In addition, the variance in facial attractiveness explained by the genome wide homozygosity is very low (<0.15%). We did not find any significant association between the inbreeding coefficient on the MHC and facial attractiveness.

Discussion

We only find a weak association of genome- wide heterozygosity and facial attractiveness.

Is paternal height related to fertility outcomes? Evidence from the Netherlands during the secular growth trend

Over the past two centuries, the Dutch experienced a tremendous secular trend in height, and ultimately became the tallest nation in the world. Improving environmental conditions likely played the largest role in explaining these developments. But it is not yet precisely clear what factor set the Dutch head and shoulders above other nations, who were also experiencing improving environmental conditions. Could fertility also have played a role? To understand this, we would first need to know whether height and fertility were related during the secular growth trend. In this study, we investigated whether this was the case. A sample of Dutch men, birth years 1850-1900 (n = 3396), was examined. We tested the extents to which height was associated with having a certain number of children, and with having a certain number of children survive infancy. Multinomial logistic regressions were used. In terms of findings, height's relationship to fertility outcomes was curvilinear: being shorter-than-average (0.75-0.5 standard deviations below the mean height) was associated with a higher probability of being married and having five to seven children, while being moderately tall (0.5 standard deviations above the mean height) was associated with the lowest probability of being unmarried. There was no relationship between paternal height and children surviving infancy in the sample overall, but taller height was associated with a decreased risk of being in a high-mortality family among men born between 1880 and 1900. If paternal fertility played a role in the secular growth trend, we would expect to see very tall men have the most children, and clearly have the most children surviving infancy. Given this study's findings, it is unlikely that this was the case.

An open-label, 4-week, prospective clinical study evaluating the efficacy and safety of a novel targeted skin care line addressing five common skin conditions

BACKGROUND

Common skin conditions, such as irritated, dry, aging, and oily skin or dark eye circles with periorbital edema, usually do not require pharmaceutical therapy in form of dermatological drugs. They can, however, still affect the quality of life significantly. With the advent of newer cosmetics, a more targeted treatment of these dermatological conditions has become available to the public. There are few clinical studies investigating the efficacy and safety of cosmetics, leaving consumers exposed to potentially false claims of the cosmetic industry. This study aims to assess the efficacy and safety of a novel skin care series addressing the aforementioned five common skin conditions.

METHODS

This open-label, single-center, 4-week, prospective clinical study evaluated the efficacy and safety of five novel skin care formulations, each targeting one of five common skin issues in 176 study subjects. The primary endpoint parameters for the change in irritated skin, dark and puffy eyes, dry skin, aging skin, and oily skin were assessed through validated questionnaires, scales, and biomedical devices.

RESULTS

After 4 weeks of topical application of each formulation of a new targeted skin care, a significant improvement in all primary endpoints was detected. No undesirable effects occurred during this study.

CONCLUSION

This study showed a significant improvement in five common dermatological conditions with a novel targeted skin care series. Moreover, this study leads the way for an overdue critical assessment and certification of cosmetic product claims.

Our Grandmothers' Legacy: Challenges Faced by Female Ancestors Leave Traces in Modern Women's Same-Sex Relationships

Investigations of women's same-sex relationships present a paradoxical pattern, with women generally disliking competition, yet also exhibiting signs of intrasexual rivalry. The current article leverages the historical challenges faced by female ancestors to understand modern women's same-sex relationships. Across history, women were largely denied independent access to resources, often depending on male partners' provisioning to support themselves and their children. Same-sex peers thus became women's primary romantic rivals in competing to attract and retain relationships with the limited partners able and willing to invest. Modern women show signs of this competition, disliking and aggressing against those who threaten their romantic prospects, targeting especially physically attractive and sexually uninhibited peers. However, women also rely on one another for aid, information, and support. As most social groups were patrilocal across history, upon marriage, women left their families to reside with their husbands. Female ancestors likely used reciprocal altruism or mutualism to facilitate cooperative relationships with nearby unrelated women. To sustain these mutually beneficial cooperative exchange relationships, women may avoid competitive and status-striving peers, instead preferring kind, humble, and loyal allies. Ancestral women who managed to simultaneously compete for romantic partners while forming cooperative female friendships would have been especially successful. Women may therefore have developed strategies to achieve both competitive and cooperative goals, such as guising their intrasexual competition as prosociality or vulnerability. These historical challenges make sense of the seemingly paradoxical pattern of female aversion to competition, relational aggression, and valuation of loyal friends, offering insight into possible opportunities for intervention.

Facial Attractiveness of the Sisters of Istmo Zapotec Men and Muxes: Implications for the Evolution of Male Androphilia

Research shows that the female relatives of androphilic (i.e., sexually attracted to adult males) males have more children than the female relatives of gynephilic (i.e., sexually attracted to adult females) males. The mechanisms by which this occurs are unclear. The hypergyny hypothesis suggests that the female relatives of androphilic males have elevated attractiveness which allows them to obtain male partners with higher socioeconomic status, which in turn, provide them with more resources to produce and sustain multiple offspring. We tested whether the female kin of male androphiles are characterized by elevated attractiveness compared to the female kin of male gynephiles. The research was conducted among the Istmo Zapotec from Oaxaca, Mexico, where androphilic males are recognized as a third gender, muxes. We recruited 115 gynephilic men who rated the facial attractiveness of 27 women with at least one muxe sibling and 27 women with only gynephilic male siblings (i.e., control sisters). The results showed that gynephilic men found the faces of control sisters more attractive than the faces of muxe sisters. This finding is inconsistent with the hypergyny hypothesis and suggests that elevated facial attractiveness is not the mechanism by which the female relatives of androphilic males achieve elevated reproduction.

An Evolutionary Perspective on Appearance Enhancement Behavior

Researchers have highlighted numerous sociocultural factors that have been shown to underpin human appearance enhancement practices, including the influence of peers, family, the media, and sexual objectification. Fewer scholars have approached appearance enhancement from an evolutionary perspective or considered how sociocultural factors interact with evolved psychology to produce appearance enhancement behavior. Following others, we argue that evidence from the field of evolutionary psychology can complement existing sociocultural models by yielding unique insight into the historical and cross-cultural ubiquity of competition over aspects of physical appearance to embody what is desired by potential mates. An evolutionary lens can help to make sense of reliable sex and individual differences that impact appearance enhancement, as well as the context-dependent nature of putative adaptations that function to increase physical attractiveness. In the current review, appearance enhancement is described as a self-promotion strategy used to enhance reproductive success by rendering oneself more attractive than rivals to mates, thereby increasing one's mate value. The varied ways in which humans enhance their appearance are described, as well as the divergent tactics used by women and men to augment their appearance, which correspond to the preferences of opposite-sex mates in a heterosexual context. Evolutionarily relevant individual differences and contextual factors that vary predictably with appearance enhancement behavior are also discussed. The complementarity of sociocultural and evolutionary perspectives is emphasized and recommended avenues for future interdisciplinary research are provided for scholars interested in studying appearance enhancement behavior.

Morphological Uniqueness: The Concept and Its Relationship to Indicators of Biological Quality of Human Faces from Equatorial Africa

Facial symmetry, averageness, and the level of sex-typical development of dimorphic traits are traditionally associated with various biological quality indicators and should be, therefore, preferred in mate choice. The aim of this study is to propose a concept of morphological uniqueness and uncover its possible associations to putative phenotypic cues of biological quality. In contrast to typicality expressed by averageness, morphological uniqueness quantifies the degree of possessing characteristics unique to particular groups. I employed a combination of geometric morphometric and Bayesian multiple regression to analyze 300 Cameroonian faces, while an additional 1153 faces from eight distinct populations from across four continents were used as a reference sample of the global population to calculate the morphological uniqueness of Cameroonians. I found that morphological uniqueness is positively associated with a feminine facial shape in women and negatively with morphological masculinity in men. Facial symmetry was positively associated with female faces with greater levels of uniqueness; the result for male faces was inconclusive. The faces of both sexes perceived as more attractive had lower levels of morphological uniqueness. Facial distinctiveness showed no relationship to morphological uniqueness in either sex, which indicates that morphological uniqueness and distinctiveness are two complementary approaches to studying facial typicality. In the conclusion, the evolutionary significance of the proposed concept and its potential applicability is discussed.

Capital as an Integrative Conceptualisation of Human Characteristics, Behaviour, and Outcomes Predicting Reproductive Success and Evolutionary Fitness

According to evolutionary theory, human cognition and behaviour are based on adaptations selected for their contribution to reproduction in the past, which in the present may result in differential reproductive success and inclusive fitness. Because this depiction is broad and human behaviour often separated from this ultimate outcome (e.g., increasing childlessness), evolutionary theory can only incompletely account for human everyday behaviour. Moreover, effects of most studied traits and characteristics on mating and reproductive success turned out not to be robust. In this article, an abstract descriptive level for evaluating human characteristics, behaviour, and outcomes is proposed, as a predictor of long-term reproductive success and fitness. Characteristics, behaviour, and outcomes are assessed in terms of attained and maintained capital, defined by more concrete (e.g., mating success, personality traits) and abstract (e.g., influence, received attention) facets, thus extending constructs like embodied capital and social capital theory, which focuses on resources embedded in social relationships. Situations are framed as opportunities to gain capital, and situational factors function as elicitors for gaining and evaluating capital. Combined capital facets should more robustly predict reproductive success and (theoretically) fitness than individual fitness predictors. Different ways of defining and testing these associations are outlined, including a method for empirically examining the psychometric utility of introducing a capital concept. Further theorising and empirical research should more precisely define capital and its facets, and test associations with (correlates of) reproductive success and fitness.

Can Sexual Appeal, Beauty, or Virtue Increase the Opportunity for a Woman to Be Selected as a Spouse? The Mediating Role of Human Uniqueness

High mating value is believed to correspond with high mating opportunities. On that premise, this study explores three cues that are linked to women of high long-term mating value, namely a "beautiful" facial appearance, "sexually attractive" body shape, and "virtuous" behavior. With exclusive attention focused on the above cues, this study examines what kind of human attributes would make a contribution to women's mating opportunities. The results reveal that both "beautiful" women and "virtuous" women were assessed (in this study) as having greater mating opportunities than "sexually attractive" women. In regard to the human attributes, only the "beautiful" woman was assessed as having high levels of human uniqueness and human nature. Meanwhile, "virtuous" women were assessed as having higher levels of human uniqueness but lower levels of human nature. In contrast, "sexually attractive" women were assessed as having lower levels of human uniqueness but higher levels of human nature. In addition, the results of a mediation analysis show that the trait of human uniqueness, and not human nature, was the mediator between the three types of women and women's mating opportunities. This finding means that, when women have higher levels of human uniqueness, they can acquire more mating opportunities. These findings contribute an improved understanding to why and how "beauty" or "virtue" increases the opportunity for woman to be selected as a spouse.

Children's affectionate and assertive attitudes towards their parents: the Oedipus complex or parent-offspring conflict?

Being one of Freud's most famous contributions to psychoanalysis, the Oedipus complex is still a topic of heated interest. It has been disputed in many different disciplines ranging from anthropology to biology. This theoretical paper aimed to explain the phenomena that are represented by children's affectionate and assertive attitudes towards their parents, named as the Oedipus complex by some, in terms of parent-offspring conflict, sibling competition, and infanticide. All of these evolutionary biological concepts or their combination could conceive specific relational settings similar to those emerging in the Oedipus complex. Psychoanalysis surely acknowledges the effects of parent-offspring conflict or sibling dynamics on familial relations and character formation. Nevertheless, they have been generally overshadowed by other primary theoretical concepts. Considering the findings from evolutionary biology and developmental psychology, it was asserted that parent-offspring conflict and sibling dynamics must be included in the conceptualization of oedipal-like behaviors. In light of these hypotheses, related literature and suggestions for further studies were discussed.

Predicted reproductive longevity and women's facial attractiveness

Physical attractiveness has been shown to reflect women's current fecundity level, allowing a man to choose a potentially more fertile partner in mate choice context. However, women vary not only in terms of fecundity level at reproductive age but also in reproductive longevity, both influencing a couple's long-term reproductive success. Thus, men should choose their potential partner not only based on cues of current fecundity but also on cues of reproductive longevity, and both may be reflected in women's appearance. In this study, we investigated if a woman's facial attractiveness at reproductive age reflects anti-Müllerian hormone (AMH) level, a hormone predictor of age at menopause, similarly as it reflects current fecundity level, estimated with estradiol level (E2). Face photographs of 183 healthy women (Mage = 28.49, SDage = 2.38), recruited between 2nd - 4th day of the menstrual cycle, were assessed by men in terms of attractiveness. Women's health status was evaluated based on C-reactive protein level and biochemical blood test. Serum AMH and E2 were measured. The results showed that facial attractiveness was negatively correlated with AMH level, a hormone indicator of expected age at menopause, and positively with E2, indicator of current fecundity level, also when controlled for potential covariates (testosterone, BMI, age). This might result from biological trade-off between high fecundity and the length of reproductive lifespan in women and greater adaptive importance of high fecundity at reproductive age compared to the length of reproductive lifespan.

Experimental Evidence for Sex Differences in Sexual Variety Preferences: Support for the Coolidge Effect in Humans

We examined sex differences in preferences for sexual variety and novelty to determine whether the Coolidge effect plays a role in human sexuality. In two experimental studies that employed different manipulations, we found converging evidence that men showed a greater preference for variety in potential short-term mates than did women. In the first study, men (n = 281) were more likely than women (n = 353) to select a variety of mates when given the opportunity to distribute chances to have sex with different individuals in hypothetical situations. This sex difference was evident regardless of the targets' attractiveness and age. Further, men found it more appealing if their committed romantic/sexual partners frequently changed their physical appearance, while women reported that they modified their physical appearance more frequently than did men, potentially appealing to male desires for novelty. In the second study, when participants were given a hypothetical dating task using photographs of potential short-term mates, men (n = 40) were more likely than women (n = 56) to select a novel person to date. Collectively, these findings lend support to the idea that sex differences in preferences for sexual variety and novelty are a salient sex-specific evolved component of the repertoire of human mating strategies.

Adult temperament and childbearing over the life course

Emerging evidence suggests that temperament may predict childbearing. We examined the association between four temperament traits (novelty seeking, harm avoidance, reward dependence and persistence of the Temperament and Character Inventory) and childbearing over the life course in the population‐based Cardiovascular Risk in Young Finns study (n = 1535; 985 women, 550 men). Temperament was assessed when the participants were aged 20–35 and fertility history from adolescence to adulthood was reported by the participants at age 30–45. Discrete‐time survival analysis modelling indicated that high childbearing probability was predicted by low novelty seeking (standardized OR = 0.92; 95% confidence interval 0.88–0.97), low harm avoidance (OR = 0.90; 0.85–0.95), high reward dependence (OR = 1.09; 1.03–1.15) and low persistence (OR = 0.91; 0.87–0.96) with no sex differences or quadratic effects. These associations grew stronger with increase in numbers of children. The findings were substantially the same in a completely prospective analysis. Adjusting for education did not influence the associations. Despite its negative association with overall childbearing, high novelty seeking increased the probability of having children in participants who were not living with a partner (OR = 1.29; 1.12–1.49). These data provide novel evidence for the role of temperament in influencing childbearing, and suggest possible weak natural selection of temperament traits in contemporary humans. Copyright © 2009 John Wiley & Sons, Ltd.

Hedonic Responses to Touch are Modulated by the Perceived Attractiveness of the Caresser

Previous research has shown that a specific type of C fiber, the C tactile afferents, are involved in detecting gentle, dynamic tactile stimuli on the skin, giving rise to affective responses in the central nervous system. Despite building on such bottom-up information flow, the hedonic perception and the physiological consequences of affective touch are influenced by various sources of top-down information. In the present study we investigated how perception of affective touch is influenced by the attractiveness of hypothetical caressers. Participants were stroked on the arm and the palm while looking at photos of high attractive and low attractive opposite-gender faces, and were instructed to imagine those people as the caressers. In a control condition no photo was paired with the touch. The stroking stimulation was delivered with a soft brush either on the forearm or on the palm, and either with a slower or faster speed. Participants rated the pleasantness of each stimulation, while electrocardiographic recordings were made to extract heart rate variability data. Results showed that participants preferred touch stimuli paired with high attractive faces; they also preferred palm stroking and slower stroking speed. Like subjective pleasantness ratings, heart rate variability responses to affective touch (slow) were higher for high attractive than for low attractive caressers, but were not selective for arm or palm stroking. Overall, the present study confirms that contextual social information plays a major role in affective touch experiences, influencing not only the hedonic quality of the experience but also the physiological state of the body.

In humans, only attractive females fulfil their sexually imprinted preferences for eye colour

Early exposure to parental features shapes later sexual preferences in fish, birds, and mammals. Here I report that human males' preferences for a conspicuous trait, colourful eyes, are affected by the eye colour of mothers. Female faces with light (blue or green) eyes were liked better by men whose mother had light eyes; the effect broke down in those who had felt rejected by her as children. These results, garnered on over one thousand men, complete those of a symmetrical study on one thousand women, painting a fuller picture of human sexual imprinting. Both men and women appear to have imprinted on their opposite-sex parents unless these were perceived as cold and unjustly punitive. Birds require strong attachment to sexually imprint-a constraint in place to reduce the perils of acquiring the wrong sort of information. Parents who form no bond with their offspring may fail to be recognised as appropriate parental imprinting objects. Consistent with human females being, as in most of the animal kingdom, the choosier sex, imprinted preferences were displayed by both sexes but translated into real-life partner choices solely in women-attractive women. Apparently, not all of us can afford to follow our own inclinations.

Individual differences in preference for risky behaviors during courtship

Engaging in risky behaviors is a sexual signalling strategy that men use to procure mates. The present study investigates men's preferences for engaging in risky behaviors (along with women's preferences for their male partner's risky behavior) within dating couples. We investigated associations between relationship length, self-perceived attractiveness, sociosexuality orientation, and preference for risky behaviors in a sample of 256 couples. Results indicated that men had stronger preferences for risky behaviors than their partner's ideal preference. Furthermore, relationship length was associated with a decline in women's preference for their partner's risk-taking, but not men's preference for their own risk-taking. Self-perceived attractiveness was negatively associated with risk preference, and sociosexuality orientation was not directly related to risk preference. Female preferences for less intense male risky behaviors could reflect the need of paternal investment which is required for offspring care. Decreased male sexual signalling could account for lower preferences of risky behaviors in females who are involved in longer lasting romantic relationships.

Offspring Production Among the Relatives of Istmo Zapotec Men and Muxes

Male androphilia (i.e., sexual attraction toward adult males) is influenced by biological factors, reliably occurs across diverse cultures, and has persisted over evolutionary time despite the fact that it reduces reproduction. One possible solution to this evolutionary paradox is the sexually antagonistic gene hypothesis (SAGH), which states that genes associated with male androphilia reduce reproduction when present in males but increase reproduction when present in their female relatives. The present study tested the SAGH among the Istmo Zapotec-a non-Euro-American culture in Oaxaca, Mexico, where transgender and cisgender androphilic males are known as muxe gunaa and muxe nguiiu, respectively. To test the SAGH, we compared offspring production by the biological relatives of muxe gunaa (n = 115), muxe nguiiu (n = 112), and gynephilic men (i.e., cisgender males who are sexually attracted to adult females; n = 171). The mothers and paternal aunts of muxe gunaa had higher offspring production than those of muxe nguiiu. Additionally, the relatives of muxe gunaa had more offspring than those of gynephilic men, whereas no such differences were found between the families of gynephilic men and muxe nguiiu. Elevated reproduction by the mothers and, particularly the aunts, of muxe gunaa is consistent with the SAGH. However, the absence of group differences between gynephilic men and muxe nguiiu, and the group differences between the two types of muxes are not predicted by the SAGH. This is the first study to demonstrate reproductive differences between kin of transgender and cisgender androphilic males within the same non-Euro-American culture.

Perceived attractiveness of Czech faces across 10 cultures: Associations with sexual shape dimorphism, averageness, fluctuating asymmetry, and eye color

Research on the perception of faces typically assumes that there are some universal values of attractiveness which are shared across individuals and cultures. The perception of attractiveness may, however, vary across cultures due to local differences in both facial morphology and standards of beauty. To examine cross-cultural consensus in the ratings of attractiveness, we presented a set of 120 non-manipulated photographs of Czech faces to ten samples of raters from both European (Czech Republic, Estonia, Sweden, Romania, Turkey, Portugal) and non-European countries (Brazil, India, Cameroon, Namibia). We examined the relative contribution of three facial markers (sexual shape dimorphism, averageness, fluctuating asymmetry) to the perception of attractiveness as well as the possible influence of eye color, which is a locally specific trait. In general, we found that both male and female faces which were closer to the average and more feminine in shape were regarded as more attractive, while fluctuating asymmetry had no effect. Despite a high cross-cultural consensus on attractiveness standards, significant differences in the perception of attractiveness seem to be related to the level of socio-economic development (as measured by the Human Development Index, HDI). Attractiveness ratings by raters from low-HDI countries (India, Cameroon, Namibia) converged less with ratings from Czech Republic than ratings from high-HDI countries (European countries and Brazil). With respect to eye color, some local patterns emerged which we discuss as a consequence of negative frequency-dependent selection.

Best-worst scaling improves measurement of first impressions

A common goal in psychological research is the measurement of subjective impressions, such as first impressions of faces. These impressions are commonly measured using Likert ratings. Although these ratings are simple to administer, they are associated with response issues that can limit reliability. Here we examine best-worst scaling (BWS), a forced-choice method, as a potential alternative to Likert ratings for measuring participants' facial first impressions. We find that at the group level, BWS scores correlated almost perfectly with Likert scores, indicating that the two methods measure the same impressions. However, at the individual participant level BWS outperforms Likert ratings, both in terms of ability to predict preferences in a third task, and in terms of test-retest reliability. These benefits highlight the power of BWS, particularly for use in individual differences research.

Physical attractiveness and criminal justice processing: results from a longitudinal sample of youth and young adults

A substantial body of research examining the role that attractiveness plays in a wide range of outcomes has revealed that attractiveness is a beneficial characteristic across multiple domains of life, including some related to crime and the criminal justice system. The current study uses these findings as a springboard to examine the potential association between attractiveness and multiple measures of criminal justice processing, including being arrested, being convicted, being sentenced to probation and being incarcerated. Analysis of data drawn from the National Longitudinal Study of Adolescent to Adult Health revealed that more attractive persons were less likely to be arrested and convicted than less attractive persons, but there was no association with odds of being sentenced to probation or incarcerated. Follow-up analyses revealed that the beneficial effect of being attractive was confined solely to females. We discuss possible reasons for these results and provide suggestions for future research.

Genome-wide association study reveals sex-specific genetic architecture of facial attractiveness

Facial attractiveness is a complex human trait of great interest in both academia and industry. Literature on sociological and phenotypic factors associated with facial attractiveness is rich, but its genetic basis is poorly understood. In this paper, we conducted a genome-wide association study to discover genetic variants associated with facial attractiveness using 4,383 samples in the Wisconsin Longitudinal Study. We identified two genome-wide significant loci, highlighted a handful of candidate genes, and demonstrated enrichment for heritability in human tissues involved in reproduction and hormone synthesis. Additionally, facial attractiveness showed strong and negative genetic correlations with BMI in females and with blood lipids in males. Our analysis also suggested sex-specific selection pressure on variants associated with lower male attractiveness. These results revealed sex-specific genetic architecture of facial attractiveness and provided fundamental new insights into its genetic basis.

Facial attractiveness is a complex human trait well integrated into people’s daily life experience with profound influence on human behavior. Despite being widely studied in sociology, psychology, and related fields, its genetic basis remains poorly understood. Using carefully-measured facial attractiveness and dense genotyping data from the Wisconsin Longitudinal Study, we identified novel genes for facial attractiveness, assessed the selection signature, and dissected the shared genetic architecture between facial attractiveness and various human traits. Interestingly, sex-specific genetic architecture of facial attractiveness was a recurrent pattern observed in almost all our analyses. Our results provided new insights into the genetic basis of facial attractiveness and have broad implications for the complex relationships between attractiveness and various human traits.

Perception and Deception: Human Beauty and the Brain

Human physical characteristics and their perception by the brain are under pressure by natural selection to optimize reproductive success. Men and women have different strategies to appear attractive and have different interests in identifying beauty in people. Nevertheless, men and women from all cultures agree on who is and who is not attractive, and throughout the world attractive people show greater acquisition of resources and greater reproductive success than others. The brain employs at least three modules, composed of interconnected brain regions, to judge facial attractiveness: one for identification, one for interpretation and one for valuing. Key elements that go into the judgment are age and health, as well as symmetry, averageness, face and body proportions, facial color and texture. These elements are all Costly Signals of reproductive fitness because they are difficult to fake. However, people deceive others using tricks such as coloring hair, cosmetics and clothing styles, while at the same time they also focus on detecting fakes. People may also deceive themselves, especially about their own attractiveness, and use self-signally actions to demonstrate to themselves their own true value. The neuroscience of beauty is best understood by considering the evolutionary pressures to maximize reproductive fitness.

The influence of leg-to-body ratio, arm-to-body ratio and intra-limb ratio on male human attractiveness

Human mate choice is influenced by limb proportions. Previous work has focused on leg-to-body ratio (LBR) as a determinant of male attractiveness and found a preference for limbs that are close to, or slightly above, the average. We investigated the influence of two other key aspects of limb morphology: arm-to-body ratio (ABR) and intra-limb ratio (IR). In three studies of heterosexual women from the USA, we tested the attractiveness of male physiques that varied in LBR, ABR and IR, using figures that ranged from -3 to +3 standard deviations from the population mean. We replicated previous work by finding that the optimally attractive LBR is approximately 0.5 standard deviations above the baseline. We also found a weak effect of IR, with evidence of a weak preference for the baseline proportions. In contrast, there was no effect of ABR on attractiveness, and no interactions between the effects of LBR, ABR and IR. Our results indicate that ABR is not an important determinant of human mate choice for this population, and that IR may exert some influence but that this is much smaller than the effects of LBR. We discuss possible reasons for these results, including the limited variability in upper limb proportions and the potentially weak fitness-signal provided by this aspect of morphology.

Electrophysiological evidence of perceived sexual attractiveness for human female bodies varying in waist-to-hip ratio

The dynamics of brain activation reflecting attractiveness in humans are unclear. Among the different features affecting attractiveness of the female body, the waist-to-hip ratio (WHR) is considered to be crucial. To date, however, no event-related potential (ERP) study has addressed the question of its associated pattern of brain activation. We carried out two different experiments: (a) a behavioural study, to judge the level of attractiveness of female realistic models depicting 4 different WHRs (0.6, 0.7, 0.8, 0.9) with and without clothes; (b) an EEG paradigm, to record brain activity while participants (heterosexual men and women) viewed these same models. Behavioural results showed that WHRs of 0.7 were considered more attractive than the others. ERP analyses revealed a different pattern of activation for male and female viewers. The 0.7 ratio elicited greater positivity at the P1 level in male viewers but not females. Naked bodies increased the N190 in both groups and peaked earlier for the 0.7 ratio in the male viewers. Finally, the late positive component (LPC) was found to be greater in male than in female viewers and was globally more marked for naked bodies as well as WHRs of 0.7 in both groups of viewers. These results provide the first electrophysiological evidence of specific time periods linked to the processing of a body feature denoting attractiveness and therefore playing a role in mate choice.

Self-Rated Attractiveness Moderates the Relationship Between Dark Personality Traits and Romantic Ideals in Women

Our study investigated the different mate preferences of the Dark Triad in women. In addition to former studies, we also examined the effect of self-evaluated attractiveness on these preferences. Attractiveness is a high-valued partner attribute, especially in short-term relationships. Accordingly, we predicted that women high in Dark Triad traits prefer characteristics related to short-term mating, because they possess traits favored in short-term relationships. Associations between ideal partner standards and Dark Triad traits were investigated with self-reports: 529 female undergraduate students filled out the Short Dark Triad and the Ideal Standards Scale. Results showed that all three Dark Triad traits were related to unique preferences of mate qualities corresponding to their self-rated partner qualities. Furthermore, despite the differences between the three Dark Triad traits, women's partner preferences were associated with their self-evaluated attractiveness (an indicator of mate value). In summary, according to our findings, qualities advertised by Dark Triad women as potential partner influence their expectation or preferences regarding mates, suggesting homogamous mate choice on the levels of these qualities.

Self-Perceived Mate Value, Facial Attractiveness, and Mate Preferences: Do Desirable Men Want It All?

Ten years ago, Buss and Shackelford demonstrated that high mate value (i.e., physically attractive) women held more discerning mate preferences relative to lower mate value women. Since then, researchers have begun to consider the equally important role of men's sexual selectivity in human mate choice. Yet, little research has focused on whether high mate value men are similarly choosy in their mate preferences. In a sample of 139 undergraduate men, relationships between self-perceived mate value as well as female-rated facial attractiveness were examined in relation to men's expressed mate preferences. Results showed that self-perceived mate value was unrelated to men's facial attractiveness as rated by women. Men who believed they were of high mate value were more likely than lower mate value men to prefer to marry at a younger age; to have a spouse who was younger than them; and to have a partner who was sociable, ambitious, high in social status, with good financial prospects, a desire for children, health, good looks, and mutual attraction. Objective male facial attractiveness was generally unrelated to heightened mate preferences, with the exception of heightened preference for similar religious background and good physical health. Findings suggest that men who perceive themselves as high in overall mate value are selective in their mate choice in a manner similar to high mate value women.

The effect of leg-to-body ratio on male attractiveness depends on the ecological validity of the figures

Leg-to-body ratio (LBR) predicts evolutionary fitness, and is therefore expected to influence bodily attractiveness. Previous investigations of LBR attractiveness have used a wide variety of stimuli, including line drawings, silhouettes, and computer-generated images based on anthropometric data. In two studies, community samples of heterosexual women from the USA rated the attractiveness of male figures presented as silhouettes and as detailed computer-generated images with three different skin tones (white, black, and an artificial grey). The effects of LBR depended on the image format. In particular, a curve-fitting analysis indicated that the optimally-attractive LBR for silhouettes was fractionally below the baseline, whereas the optima for more detailed computer-generated images was approximately 0.5 s.d. above the baseline and was similar for all three skin-tones. In addition, the participants' sensitivity to changes in the LBR was lowest for the silhouettes and highest for the grey figures. Our results add to evidence that the most attractive LBR is close to, but slightly above, the population mean, and caution that the effects of limb proportions on attractiveness depend on the ecological validity of the figures.

Omitted evidence undermines sexual motives explanation for attractiveness bias

This commentary makes three points: (1) the existing evidence does not consistently favor the proposed sex difference in attractiveness preferences, nor the fitness-related outcomes of attractiveness; (2) the neglected association of perceived attractiveness and trustworthiness allowed the authors to incorrectly attribute many findings solely to attractiveness, and (3) the importance accorded attractiveness in mate preferences is culturally shaped and likely evolutionarily novel.

The relationship between health and mating success in humans

Health has been claimed to play an important role in human sexual selection, especially in terms of mate choice. Our preferences for attractive individuals are said to represent evolved adaptations for finding high-quality, healthy mates. If this is true, then we expect health to predict mating success in humans. We tested this hypothesis using several important physiological indicators of health, including immune function, oxidative stress and semen quality, and self-reported measures of sexual behaviour that contribute to mating success. In contrast to our hypothesis, we did not find a relationship between the physiological measures of health and sexual behaviour. Our results provide little support for claims that health, at least the health measures we used, increases mating success in relatively healthy humans.

The Effect of Facial Attractiveness on Facial Expression Identification

Abstract. Emotion perception studies typically explore how judgments of facial expressions are influenced by invariant characteristics such as sex or by variant characteristics such as gaze. However, few studies have considered the importance of factors that are not easily categorized as invariant or variant. We investigated one such factor, attractiveness, and the role it plays in judgments of emotional expression. We asked 26 participants to categorize different facial expressions (happy, neutral, and angry) that varied with respect to facial attractiveness (attractive, unattractive). Participants were significantly faster when judging expressions on attractive as compared to unattractive faces, but there was no interaction between facial attractiveness and facial expression, suggesting that the attractiveness of a face does not play an important role in the judgment of happy or angry facial expressions.

An Evolutionary Perspective on Mate Rejection

We argue that mate rejection and ex-partner relationships are important, multifaceted topics that have been underresearched in social and evolutionary psychology. Mate rejection and relationship dissolution are ubiquitous and form integral parts of the human experience. Both also carry with them potential risks and benefits to our fitness and survival. Hence, we expect that mate rejection would have given rise to evolved behavioral and psychological adaptations. Herein, we outline some of the many unanswered questions in evolutionary psychology on these topics, at each step presenting novel hypotheses about how men and women should behave when rejecting a mate or potential mate or in response to rejection. We intend these hypotheses and suggestions for future research to be used as a basis for enriching our understanding of human mating from an evolutionary perspective.

Effects of exogenous testosterone and mating context on men's preferences for female facial femininity

Correlational research suggests that men show greater attraction to feminine female faces when their testosterone (T) levels are high. Men's preferences for feminine faces also seem to vary as a function of relationship context (short versus long-term). However, the relationship between T and preferences for female facial femininity has yet to be tested experimentally. In the current paper, we report the results of two experiments examining the causal role of T in modulating preferences for facial femininity across both short and long-term mating contexts. Results of Experiment 1 (within-subject design, n=24) showed that participants significantly preferred feminized versus masculinized versions of women's faces. Further, participants showed a stronger preference for feminine faces in the short versus the long-term context after they received T, but not after they received placebo. Post-hoc analyses suggested that this effect was driven by a lower preference for feminine faces in the long-term context when on T relative to placebo, and this effect was found exclusively for men who received placebo on the first day of testing, and T on the second day of testing (i.e., Order x Drug x Mating context interaction). In Experiment 2 (between-subject design, n=93), men demonstrated a significant preference for feminized female faces in the short versus the long-term context after T, but not after placebo administration. Collectively, these findings provide the first causal evidence that T modulates men's preferences for facial femininity as a function of mating context.