Cross-cultural variation in men's preference for sexual dimorphism in women's faces

Both attractiveness judgements and mate preferences vary considerably cross-culturally. We investigated whether men''s preference for femininity in women''s faces varies between 28 countries with diverse health conditions by analysing responses of 1972 heterosexual participants. Although men in all countries preferred feminized over masculinized female faces, we found substantial differences between countries in the magnitude of men''s preferences. Using an average femininity preference for each country, we found men''s facial femininity preferences correlated positively with the health of the nation, which explained 50.4% of the variation among countries. The weakest preferences for femininity were found in Nepal and strongest in Japan. As high femininity in women is associated with lower success in competition for resources and lower dominance, it is possible that in harsher environments, men prefer cues to resource holding potential over high fecundity.     

Evidence of adaptation for mate choice within women's memory

Sexually dimorphic characteristics in men may act as cues, advertising long-term health, dominance, and reproductive potential to prospective mates. Evolution has accordingly adapted human cognition so that women perceive sexually dimorphic facial features as important when judging the attractiveness and suitability of potential mates. Here we provide evidence showing, for the first time, that women's memory for details encountered in recently experienced episodes is also systematically biased by the presence of men's facial cues signaling enhanced or reduced sexual dimorphism. Importantly, the direction and strength of this bias are predicted by individual differences in women's preferences for masculine versus feminine facial features in men and are triggered specifically while viewing images of male but not female faces. No analogous effects were observed in male participants viewing images of feminized and masculinized women's faces despite the fact that male participants showed strong preferences for feminized facial features. These findings reveal a preference-dependent memory enhancement in women that would promote retention of information from encounters with preferred potential mates. We propose that women's memory for recently experienced episodes may therefore be functionally specialized for mate choice and in particular for the comparative evaluation of alternative potential mates. This also raises the possibility that similar specialization may be present in other species where it has been established that precursor, ‘episodic-like’ forms of memory exist.     

Facial shape provides a valid cue to sociosexuality in men but not women

Existing work suggests that observers' perceptions of sociosexuality from strangers' faces are positively associated with individuals' self-reported sociosexuality. However it is not clear what cues observers use to form these judgements. Over two studies we examined whether sociosexuality is reflected in faces, which cues contain information about sociosexuality, and whether observers' perceptions of sociosexuality from faces are positively associated with individuals' self-reported sociosexuality. In Study One, Geometric Morphometric Modelling (GMM) analysis of 103 Caucasian participants revealed that self-reported sociosexuality was predicted by facial morphology in male but not female faces. In Study Two, 65 Caucasian participants judged the sociosexuality of opposite sex faces (faces from Study One) at zero acquaintance. Perceived sociosexuality predicted self-reported sociosexuality for men, but not women. Participants were also presented with composites of faces of individuals with more unrestricted sociosexuality paired with composites of faces of individuals with more restricted sociosexuality and asked to indicate which was more unrestricted. Participants selected the more unrestricted sociosexuality male, but not female, facial composites at rates significantly above chance. GMM analyses also found that facial morphology statistically significantly predicted perceived sociosexuality in women's and, to a greater extent, in men's faces. Finally, facial shape mediated the relationship between perceived sociosexuality and self-reported sociosexuality in men's but not women's faces. Our results suggest that facial shape acts as a valid cue to sociosexuality in men's but not women's faces.     

Men report stronger attraction to femininity in women's faces when their testosterone levels are high

Many studies have shown that women's judgments of men's attractiveness are affected by changes in levels of sex hormones. However, no studies have tested for associations between changes in levels of sex hormones and men's judgments of women's attractiveness. To investigate this issue, we compared men's attractiveness judgments of feminized and masculinized women's and men's faces in test sessions where salivary testosterone was high and test sessions where salivary testosterone was relatively low. Men reported stronger attraction to femininity in women's faces in test sessions where salivary testosterone was high than in test sessions where salivary testosterone was low. This effect was found to be specific to judgments of opposite-sex faces. The strength of men's reported attraction to femininity in men's faces did not differ between high and low testosterone test sessions, suggesting that the effect of testosterone that we observed for judgments of women's faces was not due to a general response bias. Collectively, these findings suggest that changes in testosterone levels contribute to the strength of men's reported attraction to femininity in women's faces and complement previous findings showing that testosterone modulates men's interest in sexual stimuli.     

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.     

Changes in salivary estradiol predict changes in women's preferences for vocal masculinity

Although many studies have reported that women's preferences for masculine physical characteristics in men change systematically during the menstrual cycle, the hormonal mechanisms underpinning these changes are currently poorly understood. Previous studies investigating the relationships between measured hormone levels and women's masculinity preferences tested only judgments of men's facial attractiveness. Results of these studies suggested that preferences for masculine characteristics in men's faces were related to either women's estradiol or testosterone levels. To investigate the hormonal correlates of within-woman variation in masculinity preferences further, here we measured 62 women's salivary estradiol, progesterone, and testosterone levels and their preferences for masculine characteristics in men's voices in five weekly test sessions. Multilevel modeling of these data showed that changes in salivary estradiol were the best predictor of changes in women's preferences for vocal masculinity. These results complement other recent research implicating estradiol in women's mate preferences, attention to courtship signals, sexual motivation, and sexual strategies, and are the first to link women's voice preferences directly to measured hormone levels.     

Environment contingent preferences: Exposure to visual cues of direct male–male competition and wealth increase women's preferences for masculinity in male faces

Previous studies show that parasite prevalence and mortality/health are related to cultural variation in women's preferences for attractive and masculine traits in men. Other studies have suggested that both male–male competition and wealth may also be important correlates of cross-cultural variation in women's masculinity preferences. Here we examined whether exposure to cues of direct male–male competition, violence, or wealth influenced women's face preferences. We showed women slideshows of images with cues of low and high direct male–male competition/violence or wealth and measured their visual preferences for masculine face traits. Recent visual experience changed women's preferences for facial masculinity, with women preferring more masculine male faces after exposure to images of men engaged in direct physical competition, images of weapons, or images depicting items of high monetary value. Recent visual experience had no significant effects on preferences for masculinity in same-sex faces. Given that high levels of direct physical competition and violence among males may increase the importance of direct intra-sexual competition, it may be adaptive for women to shift visual preferences in favor of males with face cues indicating physical strength and dominance over investment in such environments. Similarly, in wealthy environments investment may be less important than other aspects of quality and so it may be adaptive for women to shift visual preferences in favor of males with face cues indicating other aspects of quality over investment. Overall, our data demonstrate that preferences can be strategically flexible according to recent visual experience and support the notion of environment contingent preferences.     

Men's Preferences for Women's Femininity in Dynamic Cross-Modal Stimuli

Men generally prefer feminine women''s faces and voices over masculine women''s faces and voices, and these cross-modal preferences are positively correlated. Men''s preferences for female facial and vocal femininity have typically been investigated independently by presenting soundless still images separately from audio-only vocal recordings. For the first time ever, we presented men with short video clips in which dynamic faces and voices were simultaneously manipulated in femininity/masculinity. Men preferred feminine men''s faces over masculine men''s faces, and preferred masculine men''s voices over feminine men''s voices. We found that men preferred feminine women''s faces and voices over masculine women''s faces and voices. Men''s attractiveness ratings of both feminine and masculine faces were increased by the addition of vocal femininity. Also, men''s attractiveness ratings of feminine and masculine voices were increased by the addition of facial femininity present in the video. Men''s preferences for vocal and facial femininity were significantly and positively correlated when stimuli were female, but not when they were male. Our findings complement other evidence for cross-modal femininity preferences among male raters, and show that preferences observed in studies using still images and/or independently presented vocal stimuli are also observed when dynamic faces and voices are displayed simultaneously in video format.     

Sex differences in neural activation to facial expressions denoting contempt and disgust

The facial expression of contempt has been regarded to communicate feelings of moral superiority. Contempt is an emotion that is closely related to disgust, but in contrast to disgust, contempt is inherently interpersonal and hierarchical. The aim of this study was twofold. First, to investigate the hypothesis of preferential amygdala responses to contempt expressions versus disgust. Second, to investigate whether, at a neural level, men would respond stronger to biological signals of interpersonal superiority (e.g., contempt) than women. We performed an experiment using functional magnetic resonance imaging (fMRI), in which participants watched facial expressions of contempt and disgust in addition to neutral expressions. The faces were presented as distractors in an oddball task in which participants had to react to one target face. Facial expressions of contempt and disgust activated a network of brain regions, including prefrontal areas (superior, middle and medial prefrontal gyrus), anterior cingulate, insula, amygdala, parietal cortex, fusiform gyrus, occipital cortex, putamen and thalamus. Contemptuous faces did not elicit stronger amygdala activation than did disgusted expressions. To limit the number of statistical comparisons, we confined our analyses of sex differences to the frontal and temporal lobes. Men displayed stronger brain activation than women to facial expressions of contempt in the medial frontal gyrus, inferior frontal gyrus, and superior temporal gyrus. Conversely, women showed stronger neural responses than men to facial expressions of disgust. In addition, the effect of stimulus sex differed for men versus women. Specifically, women showed stronger responses to male contemptuous faces (as compared to female expressions), in the insula and middle frontal gyrus. Contempt has been conceptualized as signaling perceived moral violations of social hierarchy, whereas disgust would signal violations of physical purity. Thus, our results suggest a neural basis for sex differences in moral sensitivity regarding hierarchy on the one hand and physical purity on the other.     

Emotional intelligence and oscillatory responses to emotional facial expressions

Emotional intelligence-related differences in oscillatory responses to emotional facial expressions were investigated in 48 subjects (26 men and 22 women), age 18–30 years. Participants were instructed to evaluate emotional expression (angry, happy, and neutral) of each presented face on an analog scale ranging from ?100 (very hostile) to + 100 (very friendly). High emotional intelligence (EI) participants were found to be more sensitive to the emotional content of the stimuli. It showed up both in their subjective evaluation of the stimuli and in a stronger EEG theta synchronization at an earlier (between 100 and 500 ms after face presentation) processing stage. Source localization using sLORETA showed that this effect was localized in the fusiform gyrus upon the presentation of angry faces and in the posterior cingulate gyrus upon the presentation of happy faces. At a later processing stage (500–870 ms), event-related theta synchronization in high emotional intelligence subjects was higher in the left prefrontal cortex upon the presentation of happy faces, but it was lower in the anterior cingulate cortex upon the presentation of angry faces. This suggests the existence of a mechanism that can selectively increase the positive emotions and reduce negative emotions.     

Duration of oral contraceptive use predicts women's initial and subsequent subjective responses to sexual stimuli

Recent work suggests that a woman's hormonal state when first exposed to visual sexual stimuli (VSS) modulates her initial and subsequent responses to VSS. The present study investigated whether women's initial hormonal state was related to their subjective ratings of VSS, and whether this relationship differed with VSS content. We reanalyzed previously collected data from 14 naturally cycling (NC) women and 14 women taking oral contraceptives (OCs), who subjectively rated VSS at three hormonal time-points. NC women's ratings of 216 unique sexual images were collected during the menstrual, periovulatory, and luteal phases of their menstrual cycles, and OC women's ratings were collected at comparable time-points across their pill-cycles. NC women's initial hormonal state was not related to their ratings of VSS. OC women's initial hormonal state predicted their ratings of VSS with minimal contextual information and of images depicting female-to-male oral sex. Specifically, women who entered the study in the third week of their pill-cycle (OC-3 women) rated such images as less attractive at all testing sessions than did all other women. OC-3 women were also the only women to rate decontextualized VSS as unattractive at all testing sessions. These results corroborate previous studies in which women's initial hormonal state was found to predict subsequent interest in sexual stimuli. Future work, with larger samples, should more directly investigate whether OC-3 women's negative assessment of specific types of VSS reflects a reaction to the laboratory environment or a broader mechanism, wherein OC women's sexual interests decrease late in their pill-cycle.     

Endocrinology of human female sexuality,mating, and reproductive behavior

Hormones orchestrate and coordinate human female sexual development, sexuality, and reproduction in relation to three types of phenotypic changes: life history transitions such as puberty and childbirth, responses to contextual factors such as caloric intake and stress, and cyclical patterns such as the ovulatory cycle. Here, we review the endocrinology underlying women's reproductive phenotypes, including sexual orientation and gender identity, mate preferences, competition for mates, sex drive, and maternal behavior. We highlight distinctive aspects of women's sexuality such as the possession of sexual ornaments, relatively cryptic fertile windows, extended sexual behavior across the ovulatory cycle, and a period of midlife reproductive senescence—and we focus on how hormonal mechanisms were shaped by selection to produce adaptive outcomes. We conclude with suggestions for future research to elucidate how hormonal mechanisms subserve women's reproductive phenotypes.     

Environmental threat influences preferences for sexual dimorphism in male and female faces but not voices or dances

During evolution, humans faced the trade-off between preferences for feminine and masculine traits which are presumably connected to parental care, and genetic quality or provisioning abilities, respectively. Recent research has shown that environmental factors influence preferences for femininity/masculinity in potential mates. However, studies mainly focus on women's preferences for isolated cues in men. We examined the influence of pathogen and resource threat on women's and men's preference for femininity/masculinity in opposite sex unmanipulated faces, voices, and dances. Three hundred seventy (206 women) students, aged 18–35 years, from universities across the state of Sao Paulo, Brazil, were primed with newspaper-like articles on either pathogen threat (Aedes aegypti, and its mosquito-borne diseases) or resource threat (=economic crisis), and compared to a control-priming condition (lions poisoned in a Kenyan Reserve). Participants were randomly assigned to rate attractiveness of the stimuli in one of the mating strategies (i.e., short-term or long-term relationship context). After each priming article, participants rated attractiveness of pre-rated masculine and feminine stimuli of the opposite sex in a standalone-rating design. The environmental threats and the control-priming conditions were shown in a random sequence. We found that the environmental threat and the mating strategies had no systematic effect on preferences for faces, voices and behavior, suggesting that different modalities can cue to different individual qualities and can be used differently according to the environmental context and relationship strategy. The environmental threat only had a weak effect on preferences for facial femininity-masculinity: women found feminine male faces more attractive under pathogen threat, while men found feminine female faces more attractive under resource threat. This is in contrast to some previous studies, and shows that effect of ecological factors on human psychology should be submitted to a more rigorous scrutiny. The mating strategies only interacted with voice attractiveness: women rated male voices as more attractive after being primed with any type of environmental threat when considering long-term relationship context, while in men this was true when considering short-term relationship. Finally, feminine dance videos were perceived as attractive under environmental threat, irrespective of sex, type of environmental threat or mating strategy.     

Female Preferences for Male Vocal and Facial Masculinity in Videos

Vocal and facial masculinity are cues to underlying testosterone in men and influence women’s mate preferences. Consistent with the proposal that facial and vocal masculinity signal common information about men, prior work has revealed correlated female preferences for male facial and vocal masculinity. Previous studies have assessed women’s preferences for male facial and vocal masculinity by presenting faces and voices independently and using static face stimuli. By contrast, here we presented women with short video clips in which male faces and voices were simultaneously manipulated in masculinity. We found that women who preferred masculine faces also preferred masculine voices. Furthermore, women whose faces were rated as relatively more attractive preferred both facial and vocal masculinity more than did women whose faces were rated as less attractive. These findings complement other evidence for cross‐modal masculinity preferences among women and demonstrate that preferences observed in studies using still images and/or independently presented vocal stimuli are also observed when dynamic faces and voices are displayed simultaneously in video format.     

A sharp eye for her SOI: perception and misperception of female sociosexuality at zero acquaintance

Two studies supported the hypothesis that female sociosexuality can be accurately detected by strangers based on thin slices of observable behavior. Twenty-four female participants, whose sexual strategies ranged from highly restricted to highly unrestricted, were video taped while interacting with a male confederate. In Study 1, raters' judgments of the women's sociosexuality were highly correlated with the women's self-reported sociosexuality. Study 2 replicated this finding and identified specific cues perceivers used to make their judgments. We identified (1) Valid cues (e.g., eyebrow flashes, glances at the confederate), which were associated with both targets' actual sociosexuality and raters' perceptions of sociosexuality; (2) Poor cues (e.g., hand gestures, posture), which were not correlated with actual or perceived sociosexuality; and (3) Misleading cues (e.g., provocativeness of dress, physical attractiveness), which were not associated with actual sociosexuality, but were correlated with perceptions of sociosexuality. Statistically controlling for valid cues (but not poor cues or misleading cues) reduced the relationship between perceived and actual sociosexuality, suggesting that perceiving these traits may partially account for perceiver accuracy. The accurate detection of traits in others may play an important role in helping people respond adaptively to important social threats and opportunities.     

Fertility in the cycle predicts women's interest in sexual opportunism

Research over the past decade has documented clear, robust changes in women's sexual preferences and interests across the ovarian cycle. When fertile, women are particularly attracted to a number of masculine male features (e.g., masculine faces, voices, scents and bodies) and other traits, and especially when they evaluate men's “sexiness” rather than their attractiveness as long-term partners. The current research extended this line of research by examining changes in women's self-reported sexual interests across the cycle. We asked 68 normally ovulating women in committed romantic relationships to fill out questionnaires about their sexual preferences and interests (at that time, not in general) twice across their cycles: once when fertile and once during the luteal phase. Relative to during the luteal phase, fertile women expressed (a) greater emphasis on the physical attractiveness of a partner; (b) greater arousal at the sight or thought of attractive male bodily features; (c) greater willingness to engage in and interest in sex with attractive men, even ones who they do not know well (interest in sexual opportunism). These findings importantly extend our understanding of women's fertile-phase sexuality.     

Aggressor or protector? Experiences and perceptions of violence predict preferences for masculinity

Women's preferences for masculine male partners have been explained in terms of heritable health. The evidence between masculinity and health, however, is controversial and therefore, alternative explanations for masculinity preferences reflecting income inequality and protection from violence have been proposed. This study thus aimed to test the effect of exposure to violence (i.e., experiences of robberies and perceptions of danger) on the individual masculinity preferences of women and men from the capital city of Colombia, Bogota, and surrounding small towns. One hundred and fifty three adult participants (mean age ± S.D. = 31.3 ± 9.4), all heterosexual, were surveyed in reference to indicators related to health (e.g., drinking water access, frequency of illnesses), access to media (e.g., television and internet access), education (e.g., graduating from high school, attending university) and exposure to violence (e.g., frequency of robberies/attacks, feelings of danger from violence). Participants made two alternatives, preference forced-choice for masculinized and feminized versions of both rural Salvadoran and European male faces. We found that men and women exposed to higher levels of violence preferred less masculine male faces, although this effect was only significant for women. Additionally, the effect of violence exposure was more relevant for the Salvadoran stimuli. Violence contributed significantly to explaining masculinity preferences after controlling for participant age, education, access to media, and health-related factors. These preferences may reflect women's strategy to avoid male violence demonstrating that exposure to violence matters in interpersonal attraction.     

Cingulate cortex: a closer look at its gut-related functional topography

Earlier studies have documented activation of the cingulate cortex during gut related sensory-motor function. However, topography of the cingulate cortex in relationship to various levels of visceromotor sensory stimuli and gender is not completely elucidated. The aim was to characterize and compare the activation topography of the cingulate cortex in response to 1) subliminal, 2) perceived rectal distensions, and 3) external anal sphincter contraction (EASC) in males and females. We studied 18 healthy volunteers (ages 18-35 yr; 10 women, 8 men) using functional MRI blood-oxygenation-level-dependent technique. We obtained 11 axial slices (voxel vol. 2.5-6.0 x 2.5 x 2.5 mm(3)) through the cingulate cortex during barostat-controlled subliminal, liminal, and supraliminal nonpainful rectal distensions as well as EASC. Overall, for viscerosensation, the anterior cingulate cortex exhibited significantly more numbers of activated cortical voxels for all levels of stimulations compared with the posterior cingulate cortex (P < 0.05). In contrast, during EASC, activity in the posterior cingulate was larger than in the anterior cingulate cortex (P < 0.05). Cingulate activation was similar during EASC in males and females (P = 0.58), whereas there was a gender difference in anterior cingulate activation during liminal and supraliminal stimulations (P < 0.05). In females, viscerosensory cortical activity response was stimulus-intensity dependent. Intestinal viscerosensation and EASC induce different patterns of cingulate cortical activation. There may be gender differences in cingulate cortical activation during viscerosensation. In contrast to male subjects, females exhibit increased activity in response to liminal nonpainful stimulation compared with subliminal stimulation suggesting differences in cognition-related recruitment.     

The masculinity paradox: facial masculinity and beardedness interact to determine women's ratings of men's facial attractiveness

In many species, male secondary sexual traits have evolved via female choice as they confer indirect (i.e. genetic) benefits or direct benefits such as enhanced fertility or survival. In humans, the role of men's characteristically masculine androgen‐dependent facial traits in determining men's attractiveness has presented an enduring paradox in studies of human mate preferences. Male‐typical facial features such as a pronounced brow ridge and a more robust jawline may signal underlying health, whereas beards may signal men's age and masculine social dominance. However, masculine faces are judged as more attractive for short‐term relationships over less masculine faces, whereas beards are judged as more attractive than clean‐shaven faces for long‐term relationships. Why such divergent effects occur between preferences for two sexually dimorphic traits remains unresolved. In this study, we used computer graphic manipulation to morph male faces varying in facial hair from clean‐shaven, light stubble, heavy stubble and full beards to appear more (+25% and +50%) or less (?25% and ?50%) masculine. Women (N = 8520) were assigned to treatments wherein they rated these stimuli for physical attractiveness in general, for a short‐term liaison or a long‐term relationship. Results showed a significant interaction between beardedness and masculinity on attractiveness ratings. Masculinized and, to an even greater extent, feminized faces were less attractive than unmanipulated faces when all were clean‐shaven, and stubble and beards dampened the polarizing effects of extreme masculinity and femininity. Relationship context also had effects on ratings, with facial hair enhancing long‐term, and not short‐term, attractiveness. Effects of facial masculinization appear to have been due to small differences in the relative attractiveness of each masculinity level under the three treatment conditions and not to any change in the order of their attractiveness. Our findings suggest that beardedness may be attractive when judging long‐term relationships as a signal of intrasexual formidability and the potential to provide direct benefits to females. More generally, our results hint at a divergence of signalling function, which may result in a subtle trade‐off in women's preferences, for two highly sexually dimorphic androgen‐dependent facial traits.     

The role of facial hair in women's perceptions of men's attractiveness,health, masculinity and parenting abilities

Facial hair strongly influences people's judgments of men's socio-sexual attributes. However, the nature of these judgments is often contradictory. The levels of intermediate facial hair growth presented to raters and the stage of female raters' menstrual cycles might have influenced past findings. We quantified men's and women's judgments of attractiveness, health, masculinity and parenting abilities for photographs of men who were clean-shaven, lightly or heavily stubbled and fully bearded. We also tested the effect of the menstrual cycle and hormonal contraceptive use on women's ratings. Women judged faces with heavy stubble as most attractive and heavy beards, light stubble and clean-shaven faces as similarly less attractive. In contrast, men rated full beards and heavy stubble as most attractive, followed closely by clean-shaven and light stubble as least attractive. Men and women rated full beards highest for parenting ability and healthiness. Masculinity ratings increased linearly as facial hair increased, and this effect was more pronounced in women in the fertile phase of the menstrual cycle, although attractiveness ratings did not differ according to fertility. Our findings confirm that beardedness affects judgments of male socio-sexual attributes and suggest that an intermediate level of beardedness is most attractive while full-bearded men may be perceived as better fathers who could protect and invest in offspring.