No Compelling Evidence that Preferences for Facial Masculinity Track Changes in Women's Hormonal Status

Ovarian hormones predict cooperative strategies updating during multiple rounds of the prisoner's dilemma

Increasing research has focused on how ovarian hormones influence individual prosocial motivation and cooperation. However, most results remain ambiguous and contradictory. Here, we collected progesterone (PROG) and oestradiol from 62 healthy women with regular menstrual cycles to explore whether variations in ovarian hormones could flexibly change their cooperative preference according to their opponents' strategies in multiple rounds of a prisoner's dilemma (PD) game. Participants in different menstrual phases (32 in the follicular phase [FP] and 30 in the luteal phase [LP]) were asked to complete 20 rounds of PD games with each of three computer opponents holding different cooperative strategies. The results revealed that in PD games that did not require cooperation for increased outcomes, women in the LP (high PROG) reduced their cooperation rate more significantly than women in the FP (low PROG). In contrast, when the game design required reciprocity, simultaneously elevated levels of PROG and oestradiol predicted greater instances of participants choosing to cooperate. Furthermore, we found that elevated PROG levels accounted for women's elevated prosocial choices, regardless of the need to increase outcomes through cooperation. These results implied higher levels of PROG and oestradiol influence women's cooperative strategies resulting in increased social interactions.

Sexual Dimorphism: The Interrelation of Shape and Color

Sex-typicality displayed as sexual dimorphism of the human face is a key feature enabling sex recognition. It is also believed to be a cue for perceiving biological quality and it plays an important role in the perception of attractiveness. Sexual dimorphism of human faces has two main components: sexual shape dimorphism of various facial features and sexual color dimorphism, generally manifested as dimorphism of skin luminance, where men tend to be darker than women. However, very little is known about the mutual relationship of these two facets. We explored the interconnection between the dimorphism of face shape and dimorphism of face color in three visually distinct populations (Cameroonian, Czech, and Vietnamese). Our results indicated that populations which showed a significant dimorphism in skin luminance (Cameroon, Vietnam) had low levels of sexual shape dimorphism, while a population with higher levels of sexual shape dimorphism (Czech Republic) did not exhibit a significant dimorphism of skin luminance. These findings suggest a possible compensatory mechanism between various domains of sexual dimorphism in populations differing in the levels of shape and color dimorphism.

Combined estrogen-progestin oral contraceptives and female sexuality: an updated review

INTRODUCTION

Sexual side effects of combined oral contraceptives (COCs) have not been fully understood, but increasing evidence prompts broader risk/benefit evaluation and merits inclusion in counseling on contraceptive options.

OBJECTIVES

The study sought to explore the impact of combined estrogens-progestin oral contraceptives on components of female sexuality, including sexual desire, anatomic genitourinary changes, lubrication, orgasm, provoked vestibulodynia, well-being, body image, partner preference, and relationship stability.

METHODS

A literature review was performed between April 2023 and January 2024 exploring the association between combined oral contraceptive pills and sexual health.

RESULTS

Although COCs decrease free testosterone, it is unclear if COCs affect sexual function, including desire. Antiandrogenic COCs do seem to have a negative effect on sexual arousal, lubrication, and orgasm. Provoked vestibulodynia may be related to early onset of COC use, low-estrogen pills, and antiandrogenic progestins. Emotional and sexual side effects are strong predictors of COC discontinuation. Longitudinal data indicate that using COCs when meeting and selecting a partner has implications on sexual satisfaction and relationship length. Analysis of data is complicated by various doses and forms of estrogen and progestin in COCs, which have changed over time.

CONCLUSION

Lack of randomized placebo-controlled studies and heterogenicity in study design hampers generalized statements about the effects of COCs on sexual function. Despite these challenges, consideration of sexual dysfunction when presenting and prescribing hormonal contraception is essential for informed consent, shared decision making, and ensuring reliable contraceptive choices.

Interactive effects of participant and stimulus race on cognitive performance in youth: Insights from the ABCD study

An extensive literature shows that race information can impact cognitive performance. Two key findings include an attentional bias to Black racial cues in U.S. samples and diminished recognition of other-race faces compared to same-race faces in predominantly White adult samples. Yet face stimuli are increasingly used in psychological research often unrelated to race (Conley et al., 2018) or without consideration for how race information may influence cognitive performance, especially among developmental participants from different racial groups. In the current study we used open-access data from the Adolescent Brain Cognitive DevelopmentSM (ABCD) Study® 4.0.1 release to test for developmentally similar other- and same-race effects of Black and White face stimuli on attention, working memory, and recognition memory in 9- and 10-year-old Black and White children (n=5,659) living in the U.S. Black and White children showed better performance when attending to Black versus White faces. We also show an advantage in recognition memory of same-race compared to other-race faces in White children that did not generalize to Black children. Together the findings highlight how race information, even when irrelevant to an experiment, may indirectly lead to misinterpretation of group differences in cognitive performance in children of different racial backgrounds.

Re-evaluating the Role of Partnership-Related Perceptions in Women's Preferences for Men with Masculine Face Shapes

Many researchers have proposed that women perceive men with masculine face shapes to be less suitable as parents and long-term partners than men with feminine face shapes, causing women to find masculine men more attractive for short-term than long-term relationships. However, recent work shows that results obtained using the type of experimentally manipulated stimuli that were employed in studies presenting evidence for these claims are not necessarily observed when natural (i.e., unmanipulated) face stimuli were used to suggest that the evidence for these claims may need to be revaluated. Consequently, we tested for possible relationships between ratings of natural male faces for parenting- and relationship-related traits and shape masculinity (Study 1) and also tested whether women's preferences for shape masculinity were stronger when natural male faces were rated for short-term relationships than when natural male faces were rated for long-term relationships (Studies 2 and 3). We saw no evidence for either of these predictions, instead finding that men with more attractive faces were perceived to be better parents and better long-term partners. Thus, our findings do not support the widely held view that masculine men are more attractive for short-term relationships because they are perceived to be unlikely to invest time and effort in their romantic partners and offspring.

Does the interplay of emotion-related personality traits and reproductive hormones predict individual variation in emotion recognition?

Person-related variation has been identified in many socio-cognitive domains, and there is evidence for links between certain personality traits and individual emotion recognition. Some studies, utilizing the menstrual cycle as a hormonal model, attempted to demonstrate that hormonal fluctuations could predict variations in emotion recognition, but with merely inconsistent findings. Remarkably, the interplay between hormone fluctuations and other person-related factors that could potentially influence emotion recognition remains understudied. In the current study, we examined if the interactions of emotion-related personality traits, namely openness, extraversion, and neuroticism, and the ovulatory cycle predict individual variation in facial emotion recognition in healthy naturally cycling women. We collected salivary ovarian hormones measures from N = 129 (n = 72 validated via LH test) women across their late follicular and mid-luteal phases of the ovulatory cycle. The results revealed a negative association between neuroticism scores and emotion recognition when progesterone levels (within-subject) were elevated. However, the results did not indicate a significant moderating influence of neuroticism, openness, and extraversion on emotion recognition across phases (late follicular vs. mid-luteal) of the menstrual cycle. Additionally, there was no significant interaction between openness or extraversion and ovarian hormone levels in predicting facial emotion recognition. The current study suggests future lines of research to compare these findings in a clinical setting, as both neuroticism and ovarian hormone dysregulation are associated with some psychiatric disorders such as premenstrual dysphoric disorder (PMDD).

No evidence that sociosexual orientation moderates effects of conception probability on women's preferences for male facial masculinity

Although many researchers have proposed that women will show stronger preferences for male facial masculinity when conception probability is high, empirical tests of this hypothesis have produced mixed results. One possible explanation for these inconsistent findings is that effects of conception probability on women's preferences for facial masculinity are moderated by additional factors not typically considered in these empirical tests. One such potential moderator is individual differences in women's openness to uncommitted sexual relationships (i.e., individual differences in women's sociosexual orientation); women who are more open to uncommitted sexual relationships might show stronger positive effects of conception probability on masculinity preferences, as their sexuality is more overt and sexual attitudes and behaviours are more diversified. Consequently, we analysed data from three independent samples (N = 2304, N = 483, and N = 339) to assess whether sociosexual orientation moderates the hypothesised positive effect of conception probability on women's facial masculinity preferences. Analyses showed no evidence that higher conception probability increased preferences for facial masculinity or that sociosexual orientation moderated the effect of conception probability on women's preferences for facial masculinity. While it remains possible that factors other than sociosexual orientation moderate effects of conception probability on masculinity preferences, our null results suggest that the mixed results for the effects of conception probability on facial masculinity preferences in previous studies are unlikely to be a consequence of failing to consider the moderating role of sociosexual orientation.

Facial Attractiveness, but not Facial Masculinity, is Used as a Cue to Paternal Involvement in Fathers

Purpose

Facial femininity in men is purportedly used as a cue by women as a signal of paternal involvement. However, evidence for this claim is questionable. Previous findings have shown that paternal involvement is linked to testosterone, but have not investigated facial masculinity directly, while other studies have found that facial masculinity is negatively associated with perceptions of paternal involvement but do not assess the accuracy of this judgement. Here, we assess whether facial masculinity in men is used as a cue to paternal involvement, and whether this cue is accurate.

Methods

We collected facial photographs of 259 men (156 of which were fathers) who also completed self-report measures of paternal involvement. Facial images were then rated by a separate group of raters on facial masculinity, attractiveness, and perceived paternal involvement. Shape sexual dimorphism was also calculated from the images using geometric morphometrics.

Results

We found that facial masculinity was not associated with perceptions of paternal involvement, nor was it related with self-reported paternal involvement. Interestingly, facial attractiveness was negatively associated with perceptions of paternal involvement, and we found partial evidence that facial attractiveness was also negatively associated with self-reported paternal involvement.

Conclusion

These findings challenge the hypothesis that sexual dimorphism is used as a cue to paternal involvement, and perhaps indicate that facial attractiveness is more important for this judgement instead.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40750-023-00217-y.

Not within spitting distance: Salivary immunoassays of estradiol have subpar validity for predicting cycle phase

Salivary steroid immunoassays are widely used in psychoneuroendocrinological studies of menstrual cycle phase, puberty, and menopause. Though manufacturers advertise their assays as suitable, they have not been rigorously validated for these purposes. We collated data from eight menstrual cycle studies across > 1200 female participants and > 9500 time points. Seven studies collected saliva and one collected serum. All assayed estradiol and progesterone and had an independent measure of cycle phase (LH-surge, menstrual onset). In serum, cycle phase measures strongly predicted steroid concentrations. In saliva, cycle phase poorly predicted estradiol values, which showed an upward bias compared to expectations from serum. For salivary progesterone, predictability from cycle phase was mixed, low for enzyme-linked assays and moderate for tandem mass spectrometry. Imputing the population-average serum steroid changes from cycle phase may yield more valid values of hormonal changes for an independent person than directly assessing their hormone levels using salivary immunoassays.

Preference for Male Risk Takers Varies with Relationship Context and Health Status but not COVID Risk

Risk taking is more commonly shown by males than females and has a signalling function, serving to advertise one's intrinsic quality to prospective mates. Previous research has established that male risk takers are judged as more attractive for short-term flings than long-term relationships, but the environmental and socioeconomic context surrounding female preferences for male risk takers has been overlooked. Using a survey instrument, we examined female preferences for male risk takers across 1304 females from 47 countries. We found preferences for physical risk takers to be more pronounced in females with a bisexual orientation and females who scored high on risk proneness. Self-reported health was positively associated with preferences for high risk takers as short-term mates, but the effect was moderated by country-level health, i.e. the association was stronger in countries with poorer health. The security provided by better health and access to health care may allow females to capitalise on the genetic quality afforded by selecting a risk-prone male whilst concurrently buffering the potential costs associated with the risk taker's lower paternal investment. The risk of contracting COVID-19 did not predict avoidance of risk takers, perhaps because this environmental cue is too novel to have moulded our behavioural preferences.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40806-023-00354-3.

The role of hormones in attraction and visual attention to facial masculinity

The current study investigated the ovulatory shift hypothesis, which suggests that women prefer more masculine traits when estradiol is high, and progesterone is low (E/P ratio). The current study used an eye tracking paradigm to measure women's visual attention to facial masculinity across the menstrual cycle. Estradiol (E) and progesterone (P) were collected to determine if salivary biomarkers were associated with visual attention to masculine faces in a short- and long-term mating context. Women (N = 81) provided saliva samples at three time points throughout their menstrual cycle and were asked to rate and view men's faces that had been manipulated to appear feminine and masculine. Overall, masculine faces were viewed longer compared to feminine faces and this was moderated by mating context, where women viewed masculine faces longer for a long-term relationship. There was not any evidence suggesting that E/P ratio was associated with preferences for facial masculinity, but there was evidence to suggest that hormones were associated with visual attention to men in general. In line with sexual strategies theory, there was evidence to suggest that mating context and facial masculinity are important in mate choice; however, there was no evidence to suggest that women's mate choice was associated with shifts across the menstrual cycle.

Femme/Butch/Androgyne Identity and Preferences for Femininity Across Face, Voice, and Personality Traits in Chinese Lesbian and Bisexual Women

Studies indicate that individuals preferring masculinity/femininity in one domain also prefer it in other domains. Heterosexual men and women and gay men have reported consistent preferences for masculinity/femininity across the faces and voices of their preferred sex. This study explored the femininity preferences of 417 Chinese lesbian and bisexual women in terms of face, voice pitch, vocal tract length, and personality traits and explored the effect of sexual self-labels (femme, butch, and androgyne) on these preferences. We found that lesbian and bisexual women showed a stronger preference for feminized faces, voice pitch, vocal tract length, and personality traits than masculinized versions, and these preferences were highly consistent across the four domains. Moreover, femininity preference was moderated by sexual self-labels, with butches preferring more feminine voice pitch, vocal tract length, and personality traits than femmes and androgynes. However, no significant difference was found for facial femininity preferences among different sexual self-labels. These findings present evidence of consistent femininity preference across visual, auditory, and personality traits and suggest that, regardless of sexual orientation, multiple cues may be used together when determining the attractiveness of individuals. Furthermore, these results support the hypothesis that the partner preference of lesbian and bisexual women mirrors that of heterosexual men.

Fertility Status Does Not Facilitate Women's Judgment of Male Sexual Orientation

Previous research has demonstrated that women can correctly distinguish between gay and heterosexual men's faces significantly better than chance. This ability appears to be heightened during the most fertile portion of their ovulatory cycle. Here, we sought to replicate and extend these findings in a large sample of undergraduate women (N = 1960). Although women correctly identified men's sexual orientation significantly better than chance (62% average accuracy), a subsample of naturally cycling women (n = 426) did not judge men's sexual orientation from faces more accurately when in the fertile phase of their ovulatory cycle. These results further replicate the visibility of male sexual orientation, but do not show that this ability has strong links to estimated fertility.

No increased inbreeding avoidance during the ovulatory phase of the menstrual cycle

Mate preferences and mating-related behaviours are hypothesised to change over the menstrual cycle to increase reproductive fitness. Recent large-scale studies suggest that previously reported hormone-linked behavioural changes are not robust. The proposal that women's preference for associating with male kin is down-regulated during the ovulatory (high-fertility) phase of the menstrual cycle to reduce inbreeding has not been tested in large samples. Consequently, we investigated the relationship between longitudinal changes in women's steroid hormone levels and their perceptions of faces experimentally manipulated to possess kinship cues (Study 1). Women viewed faces displaying kinship cues as more attractive and trustworthy, but this effect was not related to hormonal proxies of conception risk. Study 2 employed a daily diary approach and found no evidence that women spent less time with kin generally or with male kin specifically during the fertile phase of the menstrual cycle. Thus, neither study found evidence that inbreeding avoidance is up-regulated during the ovulatory phase of the menstrual cycle.

Fertility predicts self-development-oriented competitiveness in naturally cycling women but not hormonal contraceptive users

Objective

A growing body of research has begun investigating the relationship between hormones and female competitiveness. Many researchers have focused on the effect of the menstrual cycle and hormonal contraceptives. Despite many attempts at understanding hormone-behavior associations, contradictory findings have made it difficult to determine the existence of true effects. The aim of the current research was to use a robust methodological design to investigate the effect of fertility probability on four competitive orientations in naturally cycling women and hormonal contraceptive users.

Methods

Using a longitudinal diary study with over 3,900 observations from 21 countries, we explore the effect of fertility probability on four self-report competitive orientations after controlling for menstruation: self-developmental competition, hyper competitiveness, competition avoidance, and lack of interest toward competition.

Results

Using Bayesian estimation for ordinal mixed models, we found that fertility probability was associated with an increase in self-development competitiveness amongst naturally cycling women but not hormonal contraceptive users. We also found weak evidence that hormonal contraceptive users show reduced interest in competing compared to naturally cycling women. There were no other robust effects of fertility or hormonal contraceptive use.

Conclusions

These results suggest that fertility probability is associated with increased fluctuations in self-development competitive motivation and that hormonal contraceptives interfere with this effect. This research contributes to the growing body of literature suggesting that hormonal contraceptives may influence psychology and behavior by disrupting evolved hormonal mechanisms.

Dominance or Integration? Influence of Sexual Dimorphism and Clothing Color on Judgments of Male and Female Targets' Attractiveness, Warmth, and Competence

The face is an important source of information in social interactions. Prior studies exploring the mechanism of face perception were consistent with either dominance or integration theory. Studies have shown that both sexually dimorphic features and background cues play essential roles in the formation of impressions and the perception of facial attractiveness. In this study, we conducted two experiments to examine 539 participants' appraisal of attractiveness, warmth, and competence of the target faces of masculine and feminine men and women dressed in red, blue, or white. The results showed that: (1) feminized male/female faces were considered to have a higher degree of attractiveness, warmth, and competence, (2) people rated feminine faces wearing red higher in terms of attractiveness perception, while there was no significant effect of red on attractiveness perception of masculine faces, (3) when evaluating the warmth of targets, the promotion effect of red was found for feminine faces but not for masculine faces. This study, conducted in a pathogen disgust environment, provides direct evidence to support the integration theory over the dominance theory. Feminized red preference found in this study matches Chinese collectivism and the red cultural heritage, which has an important value for people's daily impression management and consumption decisions.

The Autumn Years: Age Differences in Preferences for Sexually Dimorphic Faces

Life history theory proposes that it is adaptive for older people to shift investment away from reproductive effort (such as mating) to survivorship. However, it remains unclear whether the shift is also present at the psychological level. We investigated this question by comparing preferences for mate choice-relevant cues, sexually dimorphic facial images, between older (60 years and older, n = 92) and younger adults (18-40 years, n = 86). Results showed that older adults had significantly smaller preferences for sexually dimorphic faces of both sexes than young adults. Specifically, both older men and women showed no significant preferences for sexually dimorphic traits when judging opposite-sex faces, and smaller preferences for masculine male faces and feminine female faces when judging same-sex faces. Young adults generally showed strong preferences for masculine male faces and feminine female faces. In Study 2, we confirmed that the absent/reduced preferences in older adults for sexually dimorphic faces did not result from poor visual ability. The smaller preferences for sexually dimorphic facial cues in older adults compared to young adults suggest that older adults may shift away from mating-oriented psychology as they become less fertile.

Hormonal contraceptives as disruptors of competitive behavior: Theoretical framing and review

Emerging evidence suggests that hormonal contraceptives (HCs) impact psychological outcomes through alterations in neurophysiology. In this review, we first introduce a theoretical framework for HCs as disruptors of steroid hormone modulation of socially competitive attitudes and behaviors. Then, we comprehensively examine prior research comparing HC users and non-users in outcomes related to competition for reproductive, social, and financial resources. Synthesis of 46 studies (n = 16,290) led to several key conclusions: HC users do not show the same menstrual cycle-related fluctuations in self-perceived attractiveness and some intrasexual competition seen in naturally-cycling women and, further, may show relatively reduced status- or achievement-oriented competitive motivation. However, there a lack of consistent or compelling evidence that HC users and non-users differ in competitive behavior or attitudes for mates or financial resources. These conclusions are tentative given the notable methodological limitations of the studies reviewed. Implications and recommendations for future research are discussed.

Do women's natural hormonal fluctuations modulate prosociality? A within-subject analysis

Prosocial behavior is central to functional societies. While studies have shown that the administration of exogenous hormones modulates prosocial propensities, it remains unclear whether natural hormonal fluctuations track women's prosocial behavior. In this study, we investigated the relationships between women's natural salivary steroid hormone levels (estradiol, progesterone, and testosterone) and their prosociality in a variety of contexts, as measured by three behavioral tasks (Charitable Donation, Social Value Orientation, and Social Discounting tasks) and one self-reported questionnaire (the Prosocial Tendencies Measure). Participants completed five weekly laboratory tests to obtain within-subject hormonal fluctuation data and prosociality measurements. In a pre-registered analysis, we found little evidence supporting the hypotheses that women's prosociality tracked natural changes in salivary estradiol, progesterone, estradiol-to-progesterone ratio, or testosterone. Our results demonstrate the importance of performing within-subject analyses when examining the relationships between hormonal levels and social behavior.

Love me Tinder: The effects of women's lifetime dating app use on daily body dissatisfaction, disordered eating urges, and negative mood

Dating apps may potentially serve as an environment that subjects young women to the harmful effects of appearance-related pressure. The current study assessed for the first time whether women's dating app use predicted body dissatisfaction (BD), urges to engage in disordered eating (DE), and negative mood in daily life. We also examined the unique effects of women's dating app partner preferences (i.e., seeking idealised versus non-idealised physical characteristics) on the aforementioned outcomes, and whether appearance-based rejection sensitivity (appearance-RS) moderated the effects of dating app use. Participants (N = 296; 100% women) first completed a baseline survey assessing lifetime dating app usage (i.e., current or former usage), partner preferences, and appearance-RS, followed by a 7-day smartphone-facilitated ecological investigation into momentary experiences of BD, DE urges (i.e., binge-eating/purging, dietary restraint, and exercise), and negative mood. Ninety-four women (32%) reported lifetime dating app usage, which, relative to non-use, predicted greater daily urges for binge-eating/purging and negative mood. However, appearance-RS failed to moderate these effects. Among dating app users, partner preferences were not a significant predictor of the central outcomes. These findings extend previous research by examining the unique effects of dating app use on everyday BD, DE urges, and negative mood. Replication and extension are encouraged.

A meta-analysis of the association between male dimorphism and fitness outcomes in humans

Humans are sexually dimorphic: men and women differ in body build and composition, craniofacial structure, and voice pitch, likely mediated in part by developmental testosterone. Sexual selection hypotheses posit that, ancestrally, more 'masculine' men may have acquired more mates and/or sired more viable offspring. Thus far, however, evidence for either association is unclear. Here, we meta-analyze the relationships between six masculine traits and mating/reproductive outcomes (96 studies, 474 effects, N = 177,044). Voice pitch, height, and testosterone all predicted mating; however, strength/muscularity was the strongest and only consistent predictor of both mating and reproduction. Facial masculinity and digit ratios did not significantly predict either. There was no clear evidence for any effects of masculinity on offspring viability. Our findings support arguments that strength/muscularity may be sexually selected in humans, but cast doubt regarding selection for other forms of masculinity and highlight the need to increase tests of evolutionary hypotheses outside of industrialized populations.

Stability and validity of steroid hormones in hair and saliva across two ovulatory cycles

Steroid hormones are often assessed via saliva samples, as they are noninvasive and easy to collect. However, hormone levels in saliva can fluctuate from moment-to-moment, are influenced by factors such as momentary emotional states and food intake, and some vary strongly across women's ovulatory cycle. In contrast, hormone levels in hair seem to be more robust against these influences and were previously suggested to be a good alternative to obtain women's baseline hormone levels. In the current study, we investigated whether hormone levels are stable across multiple assays and whether hormone levels from saliva and hair samples correlate. We collected saliva and hair samples from N = 155 naturally cycling women across two ovulatory cycles. All samples were analyzed for progesterone, testosterone and cortisol levels via mass spectrometry (LC-MS/MS). Results showed that both averaged saliva and hair hormone levels were moderately stable across cycles. Hair progesterone levels showed higher stability than the respective levels from saliva. Saliva and hair levels for progesterone and testosterone were moderately correlated, whereas cortisol levels from saliva and hair were only weakly correlated. Results suggest that the type of sample from which baseline hormone levels are assessed and the cycle phase in which saliva samples are collected may have a high impact on the obtained results. Implications for future studies are suggested.

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Testosterone, progesterone, and cortisol were analyzed from repeated saliva and hair samples via LC-MS/MS.

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Hormone levels are moderately stable in both saliva and hair samples.

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Progesterone levels are significantly more stable in hair samples as compared to saliva samples.

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Hair and saliva hormone samples correlate moderately for progesterone and testosterone, but only weakly for cortisol.

Differential effects of resource scarcity and pathogen prevalence on heterosexual women's facial masculinity preferences

The present research focused on how environmental harshness may affect heterosexual women's preferences of potential male mates' facial characteristics, namely masculinity-femininity. The evidence on this issue is mixed and mostly from Western samples. We aimed to provide causal evidence using a sample of Turkish women and Turkish male faces. A video-based manipulation was developed to heighten environmental harshness perceptions. In the main experiment, participants were primed with resource scarcity, pathogen prevalence or neither (control). They then saw masculinised vs. feminised versions of the same faces and indicated the face that they would prefer for a long-term relationship and separately rated the faces on various dimensions. In general, masculinised faces were perceived as slightly more attractive, slightly healthier and much more formidable. A multilevel Bayesian model showed that pathogen prevalence lowered the preference for masculinised faces while resource scarcity weakly elevated it. The overall drop in attractiveness ratings in cases of high perceived pathogen prevalence, one of the strongest effects we observed, suggests that during epidemics, the formation of new relationships is not a favourable strategy. Implications for evolutionary theories of mate preference are discussed.

Testing Mate Choice Hypotheses in a Transitional Small Scale Population

Objective

Tests of theories of mate choice often rely on data gathered in White, industrialised samples and this is especially the case for studies of facial attraction. Our understanding of preferences for sexual dimorphism is currently in flux and a number of hypotheses require testing in more diverse participant samples. The current study uses opportunistically gathered facial dimorphism preference data from 271 participants in rural Nicaragua, and 40 from the national capital Managua. We assess pre-registered hypotheses drawn from sexual selection theory, and from more recent approaches which consider the impacts of economic development and cultural ‘modernisation’ on mate preferences.

Methods

Participants verbally reported demographic data, and indicated preferences for five male and five female pairs of faces manipulated to differ in sexually dimorphic facial structure based on a sample of Salvadoran individuals.

Results

While urban participants showed a preference for more feminine female faces, this preference was not evident in the rural participants. Neither urban nor rural participants showed any directional preference for masculinised/feminised male faces. Furthermore, there was no support for any other pre-registered hypothesis.

Conclusions

Our results are consistent with previous studies showing no interest in facial dimorphism in less globally-acculturated, or market integrated, populations. Together, this suggests that while facial dimorphism may be subject to systematically varying preferences amongst some low-fertility, industrialised populations, it is not a feature which is likely to have been important in ancestral populations. We call for further work attempting to replicate well known mate choice phenomena in more diverse samples.

An exploratory, cross-cultural study on perception of putative cyclical changes in facial fertility cues

Although many researchers have argued that facial traits evolved as honest cues to women's current fertility (possibly via changes in facial femininity), evidence that women's facial attractiveness is significantly, positively related to probability of conception throughout menstrual cycle is mixed. These mixed results could reflect differences among studies in the methods used to assess facial attractiveness (i.e., forced choice versus rating-scale methods), differences in how fertility was assessed, differences in perceiver characteristics (e.g., their own attractiveness), and facial preferences possibly being moderated by the characteristics of the living environment. Consequently, the current study investigated the putative effect of cyclical changes in fertility on women's facial attractiveness and femininity (1) using forced choice and rating-scale method, (2) conducting both ovulation tests and repeated daily measures of estradiol assessing the conception probability, (3) based on a culturally diverse sample of perceivers, while (4) controlling for inter-individual variation. Although we found some limited evidence that women's faces became more attractive when conception probability increased, these effects differed depending on the methods used to assess both attractiveness and fertility. Moreover, where statistically significant effects were observed, the effect sizes were extremely small. Similarly, there was little robust evidence that perceivers' characteristics reliably predicted preferences for fertility cues. Collectively, these results suggest that mixed results in previous studies examining cyclical fluctuation in women's facial attractiveness are unlikely to reflect inter-cultural differences and are more likely to reflect differences in the methods used to assess facial attractiveness and fertility.

Modeling individual preferences reveals that face beauty is not universally perceived across cultures

Facial attractiveness confers considerable advantages in social interactions,^1,2 with preferences likely reflecting psychobiological mechanisms shaped by natural selection. Theories of universal beauty propose that attractive faces comprise features that are closer to the population average³ while optimizing sexual dimorphism.⁴ However, emerging evidence questions this model as an accurate representation of facial attractiveness,5, 6, 7 including representing the diversity of beauty preferences within and across cultures.8, 9, 10, 11, 12 Here, we demonstrate that Western Europeans (WEs) and East Asians (EAs) evaluate facial beauty using culture-specific features, contradicting theories of universality. With a data-driven method, we modeled, at both the individual and group levels, the attractive face features of young females (25 years old) in two matched groups each of 40 young male WE and EA participants. Specifically, we generated a broad range of same- and other-ethnicity female faces with naturally varying shapes and complexions. Participants rated each on attractiveness. We then reverse correlated the face features that drive perception of attractiveness in each participant. From these individual face models, we reconstructed a facial attractiveness representation space that explains preference variations. We show that facial attractiveness is distinct both from averageness and from sexual dimorphism in both cultures. Finally, we disentangled attractive face features into those shared across cultures, culture specific, and specific to individual participants, thereby revealing their diversity. Our results have direct theoretical and methodological impact for representing diversity in social perception and for the design of culturally and ethnically sensitive socially interactive digital agents.

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We modeled individual preferences for attractive faces in two cultures

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Attractive face features differ from the face average and sexual dimorphism

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Instead, culture and individual preferences shape attractive face features

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Attractive face features from a culture are used to judge other-ethnicity faces

Does Self-rated Attractiveness Predict Women’s Preferences for Facial Masculinity? Data From an Arab Sample

Objectives

Because more attractive women may be better able to attract and/or retain masculine mates, many researchers have proposed that women who consider themselves to be more physically attractive will show stronger preferences for men displaying masculine facial characteristics. Empirical evidence for this putative association between women’s self-rated attractiveness and preference for facial masculinity has come almost entirely from studies of Western women. Thus, we investigated whether this pattern of results also occurs in a sample of non-Western women.

Methods

We investigated the relationship between self-rated attractiveness and facial-masculinity preferences in a sample of Arab women (N = 281). Facial-masculinity preferences were assessed from attractiveness judgments of masculinized versus feminized versions of face images.

Results

By contrast with previous findings for Western women’s self-rated attractiveness, we observed no compelling evidence that Arab women who considered themselves to be more attractive showed stronger preferences for masculine men.

Conclusions

Our results suggest that previously reported associations between self-rated attractiveness and masculinity preferences might be somewhat culture specific, potentially reflecting cultural differences in typical mating strategies.

Fluctuating Asymmetry and Sexual Dimorphism in Human Facial Morphology: A Multi-Variate Study

Background

Fluctuating asymmetry is often used as an indicator of developmental instability, and is proposed as a signal of genetic quality. The display of prominent masculine phenotypic features, which are a direct result of high androgen levels, is also believed to be a sign of genetic quality, as these hormones may act as immunosuppressants. Fluctuating asymmetry and masculinity are therefore expected to covary. However, there is lack of strong evidence in the literature regarding this hypothesis.

Materials and methods

In this study, we examined a large dataset of high-density 3D facial scans of 1260 adults (630 males and 630 females). We mapped a high-density 3D facial mask onto the facial scans in order to obtain a high number of quasi-landmarks on the faces. Multi-dimensional measures of fluctuating asymmetry were extracted from the landmarks using Principal Component Analysis, and masculinity/femininity scores were obtained for each face using Partial Least Squares. The possible correlation between these two qualities was then examined using Pearson's coefficient and Canonical Correlation Analysis.

Results

We found no correlation between fluctuating asymmetry and masculinity in men. However, a weak but significant correlation was found between average fluctuating asymmetry and masculinity in women, in which feminine faces had higher levels of fluctuating asymmetry on average. This correlation could possibly point to genetic quality as an underlying mechanism for both asymmetry and masculinity; however, it might also be driven by other fitness or life history traits, such as fertility.

Conclusions

Our results question the idea that fluctuating asymmetry and masculinity should be (more strongly) correlated in men, which is in line with the recent literature. Future studies should possibly focus more on the evolutionary relevance of the observed correlation in women.

Non-Pregnant and Pregnant Women's Femininity Preferences in Male Faces: Tests Based on Within- and Between-Sex Sexual Dimorphism Facial Manipulations

Past research on women's preferences for male facial masculinity in Western cultures has produced inconsistent results. Some inconsistency may be related to the use of different facial stimulus manipulations (e.g., between-sex sexual dimorphic facial manipulation or within-sex sexual dimorphic facial manipulation) that do not perfectly avoid non-facial cues, and pregnancy status may also influence women's face preferences. We therefore recruited pregnant and nonpregnant Chinese women and manipulated the sexual dimorphism of male facial stimuli to explore the influences of manipulation methods, non-facial cues, and pregnancy status on face preferences. Results showed that: (1) in contrast with a general masculinity preference observed in Western cultures, both pregnant and nonpregnant Chinese women preferred feminized and neutral male faces generally; (2) pregnant women's preference for feminized male faces was stable across manipulation methods, while nonpregnant women preferred feminized male faces except under between-sex sexual dimorphism manipulation; and (3) manipulation methods, rather than non-facial cues, influenced participants' face preferences. Specifically, women showed the strongest preferences for femininity when face stimuli were manipulated by within-sex sexual dimorphic facial manipulation, followed by unmanipulated faces and between-sex sexual dimorphic facial manipulation. This effect was stronger for nonpregnant women in the unmanipulated condition and for pregnant women in the between-sex sexual dimorphic facial manipulation. This research provides empirical evidence of women's preferences for sexual dimorphism in male faces in a non-Western culture, as well as the effects of facial manipulation methods, pregnancy status, and the interactions between these factors.

A longitudinal evaluation of ovulatory cycle shifts in women's mate attraction and preferences

Are ovulatory cycle shifts in women's mate attraction and preferences robust? What are underlying mechanisms of potential cycle shifts? These questions are the subject of a current scientific debate surrounding the good genes ovulatory shift hypothesis. Here, we report a large, preregistered, within-subjects study, including salivary hormone measures and conception risk estimates based on luteinizing hormone tests. In four sessions across one ovulatory cycle, N = 257 women (= 1028 sessions) rated the attractiveness of 40 natural male bodies, 40 natural female bodies and 40 objects. Multilevel analyses yielded weak evidence for ovulatory increases in women's general attraction, specifically to male bodies, though they are not systematically related to changes in steroid hormone levels. Further, we found no compelling robust evidence for mate preference shifts across the cycle, as only one out of many different tests showed some weak evidence for such effects. Mechanisms regulating cycle shifts, the impact of our results on developing and revising cycle shift theories, and influences of different methodologies on results are discussed.

Cross-cultural perception of female facial appearance: A multi-ethnic and multi-centre study

Humans extract and use information from the face in assessments of physical appearance. Previous research indicates high agreement about facial attractiveness within and between cultures. However, the use of a narrow age range for facial stimuli, limitations due to unidirectional cross-cultural comparisons, and technical challenges have prevented definitive conclusions about the universality of face perception. In the present study, we imaged the faces of women aged 20 to 69 years in five locations (China, France, India, Japan, and South Africa) and secured age, attractiveness, and health assessments on continuous scales (0-100) from female and male raters (20-66 years) within and across ethnicity. In total, 180 images (36 of each ethnicity) were assessed by 600 raters (120 of each ethnicity), recruited in study centres in the five locations. Linear mixed model analysis revealed main and interaction effects of assessor ethnicity, assessor gender, and photographed participant ("face") ethnicity on age, attractiveness, and health assessments. Thus, differences in judgments of female facial appearance depend on the ethnicity of the photographed person, the ethnicity of the assessor, and whether the assessor is female or male. Facial age assessments correlated negatively with attractiveness and health assessments. Collectively, these findings provide evidence of cross-cultural variation in assessments of age, and even more of attractiveness, and health, indicating plasticity in perception of female facial appearance across cultures, although the decline in attractiveness and health assessments with age is universally found.

Menstrual Cycle Variations in Gray Matter Volume, White Matter Volume and Functional Connectivity: Critical Impact on Parietal Lobe

The role of gonadal hormones in neural plasticity remains unclear. This study aimed to examine the effects of naturally fluctuating hormone levels over the menstrual cycle in healthy females. Gray matter, functional connectivity (FC) and white matter changes over the cycle were assessed by using functional magnetic resonance imaging (fMRI), resting state fMRI, and structural MRIs, respectively, and associated with serum gonadal hormone levels. Moreover, electrocutaneous sensitivity was evaluated in 14 women in four phases of their menstrual cycle (menstrual, follicular, ovulatory, and luteal). Electrocutaneous sensitivity was greater during follicular compared to menstrual phase. Additionally, pain unpleasantness was lower in follicular phase than other phases while pain intensity ratings did not change over the cycle. Significant variations in cycle phase effects on gray matter volume were found in the left inferior parietal lobule (IPL) using voxel-based morphometry. Subsequent Freesurfer analysis revealed greater thickness of left IPL during the menstrual phase when compared to other phases. Also, white matter volume fluctuated across phases in left IPL. Blood estradiol was positively correlated with white matter volume both in left parietal cortex and whole cortex. Seed-driven FC between left IPL and right secondary visual cortex was enhanced during ovulatory phase. A seed placed in right IPL revealed enhanced FC between left and right IPL during the ovulatory phase. Additionally, we found that somatosensory cortical gray matter was thinner during follicular compared to menstrual phase. We discuss these results in the context of likely evolutionary pressures selecting for enhanced perceptual sensitivity across modalities specifically during ovulation.

Sexual orientation predicts men's preferences for sexually dimorphic face-shape characteristics: A replication study

Many researchers have proposed that straight men prefer women’s faces displaying feminine shape characteristics at least partly because mating with such women will produce healthier offspring. Although a prediction of this adaptation-for-mate-choice hypothesis is that straight men will show stronger preferences for feminized versus masculinized versions of women’s faces than will gay men, only one previous study has directly tested this prediction. Here we directly replicated that study by comparing 623 gay and 3163 straight men’s preferences for feminized versus masculinized versions of faces. Consistent with the adaptation-for-mate-choice hypothesis of straight men’s femininity preferences, we found that straight men showed significantly stronger preferences for feminized female faces than did gay men. Consistent with previous research suggesting that gay men place a premium on masculinity in potential romantic partners, we also found that gay men showed significantly stronger preferences for masculinized versions of male faces than did straight men. Together, these findings indicate the sexual orientation contributes to individual differences in men’s face preferences.

Effects of Male Facial Masculinity on Perceived Attractiveness

Studies suggest that high levels of masculinity in men can be a signal of 'better genes' as well as low parental investment. It is the trade-off between these two qualities that has led to the hypothesis that women's preferences for male masculinity are condition-dependent, yet, not all studies support this hypothesis. In addition, there is evidence that more average faces would be perceived as more attractive. Here we study the variation in masculinity preferences of a cohort of heterosexual women (n=769), using manipulated 3D faces of male subjects. We used linear mixed models to test for effects of various covariates such as relationship status, use of hormonal contraception, sociosexual orientation and self-perceived attractiveness on preference for masculinity. Our results show that women's sociosexual orientation has a positive correlation with masculinity preference while using hormonal contraception decreases this preference. None of the other covariates displayed any significant effect on masculinity preference. The initial level of masculinity of the faces (very low, low, average, high and very high) was also shown to affect this preference, where we found a significant preference for higher masculinity in the very low and average group, while no preference was found in the other groups. Our findings support the notion that condition-dependent variables have very small effects, if any, on women's preference for masculinity in men.

Facial Masculinity Increases Perceptions of Men’s Age, But Not Perceptions of Their Health: Data From an Arab Sample

Masculine characteristics in men’s faces are often assumed to function as health cues. However, evidence for this assumption from empirical tests is mixed. For example, research on Western women’s face perceptions found that masculinized versions of men’s faces were perceived to be older, but not healthier, than feminized versions. Since research on this topic has focused on Western women’s face perceptions, we investigated the effects of masculinizing face images on Arab women’s perceptions of men’s health (study 1, N = 211) and age (study 2, N = 209). Arab women perceived masculinized versions of male face images to be older, but not healthier, than feminized versions. These results add to a growing body of evidence challenging the assumption that male facial masculinity functions primarily as a health cue.

A Meta-Analysis of the "Erasing Race" Effect in the United States and Some Theoretical Considerations

The "erasing race" effect is the reduction of the salience of "race" as an alliance cue when recalling coalition membership, once more accurate information about coalition structure is presented. We conducted a random-effects model meta-analysis of this effect using five United States studies (containing nine independent effect sizes). The effect was found (ρ = 0.137, K = 9, 95% CI = 0.085 to 0.188). However, no decline effect or moderation effects were found (a "decline effect" in this context would be a decrease in the effect size over time). Furthermore, we found little evidence of publication bias. Synthetically correcting the effect size for bias stemming from the use of an older method for calculating error base rates reduced the magnitude of the effect, but the it remained significant. Taken together, these findings indicate that the "erasing race" effect generalizes quite well across experimental contexts and would, therefore, appear to be quite robust. We reinterpret the theoretical basis for these effects in line with Brunswikian evolutionary-developmental theory and present a series of predictions to guide future research in this area.