The role of mating context and fecundability in women’s preferences for men’s facial masculinity and beardedness
Introduction
The ovulatory shift hypothesis proposes that peri-ovulatory increases in women’s sexual desire occur in response to male phenotypic and behavioral traits (Gangestad and Haselton, 2015). For example, at the peri-ovulatory phase women prefer men with more masculine facial features, including defined brows, deeply set and narrow eyes, thin lips, robust midface, and a square jaw (Penton-Voak et al., 1999; Penton-Voak and Perrett, 2000; Little and Jones, 2012, Little et al., 2008). Facial masculinity is androgen dependent (Whitehouse et al., 2015), and is positively associated with men’s current health (Rhodes et al., 2003), past disease resistance (Thornhill and Gangestad, 2006), immune response (Rantala et al., 2012), physical strength (Windhager et al., 2011), social rank (Geniole et al., 2015), and mating success (Hill et al., 2013). However, investment in androgen dependent traits that are associated with mating effort may compromise paternal investment (Muller, 2017), so that masculine men may be costly as long-term partners. Facially masculine men report having more short-term than long-term sexual partners (Rhodes et al., 2005) and women accurately assigned higher sexual infidelity to facially masculine men (Rhodes et al., 2013), which may explain some of the variation in women’s facial masculinity preferences (Kruger, 2006; Perrett et al., 1998). However, women’s preferences for facial masculinity were highest at the peri-ovulatory phase of the menstrual cycle (Penton-Voak et al., 1999; Penton-Voak and Perrett, 2000; Little and Jones, 2012, Little et al., 2008), suggesting that the costs of masculinity are sometimes bypassed when heritable benefits to offspring may be gained.
Like facial masculinity, beardedness is sexually dimorphic (Trotter, 1922), androgen dependent (Randall, 2008) and enhances ratings of men’s masculinity, age, social dominance, and aggressiveness (Dixson and Vasey, 2012; Dixson and Brooks, 2013; Geniole and McCormick, 2015; Muscarella and Cunningham, 1996; Neave and Shields, 2008). Bearded men also report feeling more masculine (Wood, 1986), endorse masculine gender roles (Oldmeadow and Dixson, 2016), and have higher serum testosterone (Knussman and Christiansen, 1988). Although craniofacial masculinity and beardedness are both androgen dependent, they develop under different androgenic processes. Facial masculinity emerges as testosterone binds to androgen receptors that promote skeletal growth, beginning during fetal development (Whitehouse et al., 2015), becoming elaborated upon under the actions of testosterone during adolescence (Marečková et al., 2011), and is fully developed at adulthood (Penton-Voak and Chen, 2004). Beardedness requires the conversion of testosterone to dihydrotestosterone via 5 alpha reductase activity within hair follicles to stimulate the growth of facial hair (Farthing et al., 1982; Randall, 2008), which suggest facial masculinity varies, to some extent, independently of the capacity to grow a full beard and could signal different or convergent components of quality (Dixson et al., 2016).
Facial hair enhances the appearance of testosterone dependent facial traits, such as overall facial length and jaw size which, in turn, augments judgments of masculinity and dominance (Dixson et al., 2017a; Sherlock et al., 2017). Facial masculinity and beardedness also interact to determine women’s attractiveness judgments of men’s faces, so that slightly less masculine faces are judged as more attractive when bearded than highly masculine faces, possibly because beards mask the less masculine facial cues that may not enhance male facial attractiveness (Dixson et al., 2016). While highly masculine faces and full beards in combination may not enhance attractiveness due to appearing overly masculine, dominant and aggressive, they may be more attractive when considering short-term rather relationships and when fertility is highest. However, whether this interaction between facial masculinity and beardedness on attractiveness judgments varies over the menstrual cycle is unknown.
Although initial research provided compelling evidence for ovulatory shifts in women’s mate preferences (Gangestad and Thornhill, 2008), recent studies did not find ovulatory shifts in preferences for facial masculinity (Harris, 2011, Harris, 2013; Zietsch et al., 2015) or beardedness (Dixson and Brooks, 2013; Dixson et al., 2013; Dixson and Rantala, 2016, Dixson and Rantala, 2017). Evidence from two meta-analyses were also mixed. Wood et al. (2014) concluded that there were no ovulatory shifts in women’s mate preferences for masculinity. However, their meta-analyses estimated that the effect size (g) for masculinity preference shifts was 0.08, with a 95% CI spanning −0.01–0.16, which only just includes 0 and does not constitute strong evidence in favor of the null hypothesis. Additionally, the studies included in the estimate of cycle shift effects on masculinity preferences (k = 38) combined attractiveness judgements for faces, bodies, trait descriptions, and voices. If only studies assessing preference shifts for masculine facial shape are considered (k = 28), the estimated mean effect size more than doubles to 0.19. Gildersleeve et al. (2014) did assess cyclical preference shifts for facial masculinity, specifically, and found the significant predicted shift with an estimated effect size (g) of 0.13 overall, increasing to 0.19 for short-term contexts. Both meta-analyses reported significant cycle phase shifts across other traits relevant to the ovulatory shift hypothesis (including facial symmetry), which are not examined in the current study.
However, many of these studies were criticized for employing self-reported menstrual cycle data and variable computations of the peri-ovulatory phase in their analyses (Harris et al., 2014; Wood and Carden, 2014). Using self-reported recollected dates of menstrual bleeding may not generate accurate estimations of current fecundability (Small et al., 2007), owing to natural variation within healthy and regularly cycling women in menstrual cycle lengths (Jukic et al., 2008) and hormone levels (Jasienska and Jasienski, 2008). These natural differences reflect development in utero (Jasienska et al., 2006b), genetic differences (Jasienska et al., 2006a), body fat distribution (Ziomkiewicz et al., 2008), lifestyle factors (Jasienska, 2003) and age related changes in hormones (Lipson and Ellison, 1992). Statistical simulations suggest that between-subject designs, indirect counting methods, and low statistical power have contributed to mixed findings in past ovulatory shift research (Gangestad et al., 2016). Indirect counting methods do not predict hormonally verified peri-ovulatory periods with greater than 60% accuracy (i.e. these methods typically result in fertile window estimates where no more than 60% of the days are actually in the period of increased fecundability, Blake et al., 2016).
Peri-ovulatory increases in women’s sexual desire coincide with rises in estradiol (E) and lower progesterone (P) levels (Roney and Simmons, 2013; Jones et al., 2018a). These hormonal changes may also underpin aspects of women’s physical attractiveness (Puts et al., 2013), assertiveness (Blake et al., 2017a, Blake et al., 2017b) and mate preferences (Gangestad and Haselton, 2015). Mid-cycle levels of E were positively associated with between-subject and within-subject preferences for facial masculinity (Roney and Simmons, 2008; Roney et al., 2011; Ditzen et al., 2017). However, two studies employing within-subject designs did not report effects of E or P and instead found that testosterone levels were associated with preferences for facial masculinity (Bobst et al., 2014; Welling et al., 2007). Three recent studies employing between-subject designs also found no association between E and preferences for facial masculinity for either short-term or long-term relationships (Marcinkowska et al., 2016; Escasa-Dorne et al., 2017; Jones et al., 2018b). Additional studies testing associations between women’s hormone levels over the menstrual cycle and their mate preferences would therefore be valuable.
Here, following recent methodological recommendations targeted at reducing inconsistent findings across tests of the ovulatory-shift hypothesis (Gangestad et al., 2016), we tested whether women’s preferences for facial masculinity and beardedness vary with fecundability using three methods varying in expected reliability: with the fertile window estimated via self-report of recent menstruation commencement dates; via detection of luteinising hormone peaks to define the fertile window; and via measures of salivary estradiol and progesterone representing continuous variations in fecundability across the cycle. In Study 1, we used a large between-subjects design among 2161 women who provided sexual attractiveness ratings when considering a short-term relationship for stimuli varying in facial hair (clean-shaven, light stubble, heavy stubble, full beards) and facial masculinity (−50%, −25%, natural, +25% and +50%). This sample size is almost twice the 1213 participants recommended by Gangestad and colleagues (2016, for 80% power to detect a medium effect size of d = 0.5). In Study 2a, we used a within-subject design in which the peri-ovulatory period was confirmed via LH tests among 68 women. This sample size is again larger than the 48 participants recommended for 80% power to detect a medium effect size of d = 0.5 (Gangestad et al., 2016). We also collected salivary E and P at the low and high fertility phases of the menstrual cycle among 36 of these women to test whether shifts in E, P or the E:P ratio predicts preferences (Study 2b). This sample size is larger than some past within-subject studies reporting significant associations between estradiol and women’s facial masculinity preferences (e.g. Roney et al., 2011).
Section snippets
Photographic stimuli
Thirty-six men (mean age ± SD = 27.08 ± 5.61 years) of European descent were photographed when clean-shaven, with five days of regrowth (light stubble), 10 days of regrowth (heavy stubble) and at least four weeks of untrimmed growth (full beard) posing neutral facial expressions in front and profile view using a Canon digital camera (8.0 megapixels resolution), 150 cm from the participant under controlled lighting. The clean-shaven versions of these faces had been measured for craniofacial
Results
There was a main effect of facial hair (Table 1). Heavy stubble was most attractive followed by light stubble, then full beards and clean-shaven faces were least attractive. There was also a significant main effect of facial masculinity, which reflects the extremes of high (+50%) and low (−50%) were judged as least attractive (Fig. 2). There was a significant facial hair × facial masculinity interaction (Table 1), so that preferences were higher for faces with light stubble that were
Results
The multivariate (combined over long- and short-term relationship contexts) and univariate main effects of facial hair, facial masculinity and fertility were all significant and there were no significant two- or three-way interactions in either the multivariate or univariate analyses (Table 2). The main effects are each considered below (and see Fig. 4).
Within-subject analyses
The models including estradiol: progesterone (E:P) ratio revealed no main or interactive effects of the E:P ratio on attractiveness (Table S3). The models for estradiol showed no main effect for estradiol, but there was a facial masculinity × estradiol interaction (Table S4). An examination of simple slopes indicated that women with high estradiol preferred the un-manipulated face versus the feminized face (b = −0.10, t1204 = −2.95, p = 0.003), whereas women with low estradiol showed no facial
Discussion
With respect to facial masculinity, across two studies we found that women’s attractiveness ratings were strongest for the un-manipulated faces, followed by the feminized faces, and then the masculinized faces. This is consistent with the findings of Dixson et al. (2016), a study which used the same stimuli rated by a much larger sample of women. In both studies 1 and 2, where fertility was characterized categorically based on self-reported menstruation dates (between-subjects) and luteinising
Conflicts of interest
None.
Ethics statement
This research was carried out in accordance with the Declaration of Helsinki and was pre-approved by the Human Ethics Committee at the University of New South Wales.
Funding statement
This study was supported by an ARC Discovery Grant to RCB and BJWD, a University of Queensland Postdoctoral Fellowship to BJWD and an Australian Research Council Future Fellowship to TFD (FT140100291). These funding sources had no further role in the study design, in data collection, analysis and interpretation of the data.
References (96)
- et al.
High estradiol and low progesterone are associated with high assertiveness in women
Psychoneuroendocrinology
(2017) - et al.
Standardized methodological protocols for measuring the effects of fertility on women’s behavior: a data-driven approach contrasting counting and hormonal methods
Horm. Behav.
(2016) - et al.
No compelling positive association between ovarian hormones and wearing red clothing when using multinomial analyses
Horm. Behav.
(2017) - et al.
Early follicular testosterone level predicts preference for masculinity in male faces – but not for women taking hormonal contraception
Psychoneuroendocrinology
(2014) - et al.
The multivariate evolution of female body shape in an artificial digital ecosystem
Evol. Hum. Behav.
(2015) - et al.
The role of facial hair in women’s perceptions of men’s attractiveness, health, masculinity and parenting abilities
Evol. Hum. Behav.
(2013) - et al.
Women’s preferences for men’s beards show no relation to their ovarian cycle phase and sex hormone levels
Horm. Behav.
(2018) - et al.
Beneath the beard: do facial morphometrics influence the strength of judgments of men’s beardedness?
Evol. Hum. Behav.
(2017) - et al.
Beards and the big city: displays of masculinity may be amplified under crowded conditions
Evol. Hum. Behav.
(2017) - et al.
Human estrus: implications for relationship science
Curr. Opin. Psychol.
(2015)
How valid are assessments of conception probability in ovulatory cycle research? Evaluations, recommendations, and theoretical implications
Evol. Hum. Behav.
Facing our ancestors: judgements of aggression are consistent and related to the facial width-to-height ratio in men irrespective of beards
Evol. Hum. Behav.
Are badges of status adaptive in large complex primate groups?
Evol. Hum. Behav.
Quantifying the strength and form of sexual selection on men's traits
Evol. Hum. Behav.
Commitment to relationships and preferences for femininity and apparent health in faces are strongest on days of the menstrual cycle when progesterone level is high
Horm. Behav.
General sexual desire, but not desire for uncommitted sexual relationships, tracks changes in women’s hormonal status
Psychoneuroendocrinology
Variation in facial masculinity and symmetry preferences across the menstrual cycle is moderated by relationship context
Psychoneuroendocrinology
Preferences for variation in masculinity in real male faces change across the menstrual cycle: women prefer more masculine faces when they are more fertile
Pers. Indiv. Diff.
Lack of support for relation between woman's masculinity preference, estradiol level and mating context
Horm. Behav.
La donna è mobile? Lack of cyclical shifts in facial symmetry, and facial and body masculinity preferences—a hormone based study
Psychoneuroendocrinology
Testosterone-mediated sex differences in the face shape during adolescence: subjective impressions and objective features
Horm. Behav.
Testosterone and reproductive effort in male primates
Horm. Behav.
The evolutionary significance and social perception of male pattern baldness and facial hair
Ethol. Sociobiol.
The effects of facial hair manipulation on female perceptions of attractiveness, masculinity, and dominance in male faces
Pers. Indiv. Diff.
Female preference for male faces changes cyclically. Further evidence
Evol. Hum. Behav.
High salivary testosterone is linked to masculine male facial appearance in humans
Evol. Hum. Behav.
Women’s attractiveness changes with estradiol and progesterone across the ovulatory cycle
Horm. Behav.
Attractiveness and sexual behavior. Does attractiveness enhance mating success?
Evol. Hum. Behav.
Women’s estradiol predicts preference for facial cues of men’s testosterone
Horm. Behav.
Changes in estradiol predict within women shifts in attraction to facial cues of men's testosterone
Psychoneuroendocrinology
Hormonal predictors of sexual motivation in natural menstrual cycles
Horm. Behav.
Validity of self-reported menstrual cycle length
Ann. Epidemiol.
Facial sexual dimorphism, developmental stability, and susceptibility to disease in men and women
Evol. Hum. Behav.
Mate preferences and choices for facial and body hair in heterosexual women and homosexual men: effects of sex, population, homogamy, and imprinting-like effects
Evol. Hum. Behav.
Raised salivary testosterone in women is associated with increased attraction to masculine faces
Horm. Behav.
Likelihood of conception with a single act of intercourse: providing benchmark rates for assessment of post-coital contraceptives
Contraception
Multiple Regression: Testing and Interpreting Interactions
Mustache fashion covaries with a good marriage market for women
J. Nonverbal. Behav.
Evidence for menstrual cycle shifts in women's preferences for masculinity: a response to Harris (in press) Menstrual cycle and facial preferences reconsidered
Evolut. Psychol.
Correlated preferences for facial masculinity and ideal or actual partner's masculinity
Proc. R. Soc. Lond. B
Are attractive men's faces masculine or feminine? The importance of controlling confounds in face stimuli
J. Exp. Psychol. Hum. Percept. Perform
Effects of stress on women’s preference for male facial masculinity and their endocrine correlates
Psychoneuroendocrinology
Primate Sexuality: Comparative Studies of the Prosimians, Monkeys, Apes, and Humans
Sexual selection and the evolution of visually conspicuous sexually dimorphic traits in male monkeys, apes, and human beings
Ann. Rev. Sex. Res.
Is male facial width-to-height ratio the target of sexual selection?
Arch. Sex. Behav.
Do prevailing environmental factors influence human preferences for facial morphology?
Behav. Ecol.
The role of facial and body hair distribution in women’s judgments of men’s sexual attractiveness
Arch. Sex. Behav.
Further evidence using a continuous measure of conception probability that women's preferences for male facial and body hair may not change with fecundability
Arch. Sex. Behav.
Cited by (39)
Hormonal influences on women's extra-pair sexual interests: The moderating impact of partner attractiveness
2022, Evolution and Human BehaviorCitation Excerpt :A p-curve analysis of significant results (Simonsohn, Nelson, & Simmons, 2014) yielded evidentiary support for true effects (Gildersleeve, Haselton, & Fales, 2014b). Yet recent replications have produced mixed, though largely unsupportive, results regarding hormonal associations with women's preferences for men's facial masculinity (Dixson et al., 2018; Jones et al., 2018a; Marcinkowska, Kaminski, Little, & Jasienska, 2018), vocal masculinity (Jones et al., 2018; Jünger et al., 2018), behavioral masculinity (Stern, Gerlach, & Penke, 2020), and bodily muscularity (Jünger, Kordsmeyer, Gerlach, & Penke, 2018; Stern, Kordsmeyer, & Penke, 2021; but see Dinh, Emery Thompson, & Gangestad, 2022). Some preference shifts may be contingent on women's relationship status (Gangestad, Dinh, Grebe, Del Giudice, & Emery Thompson, 2019a, 2019b; Marcinkowska et al., 2018; see also critique by Stern, Arslan, Gerlach, & Penke, 2019), though no clear empirical picture or theoretical account has yet emerged.
Stability and validity of steroid hormones in hair and saliva across two ovulatory cycles
2022, Comprehensive PsychoneuroendocrinologyA longitudinal evaluation of ovulatory cycle shifts in women's mate attraction and preferences
2021, Hormones and BehaviorCitation Excerpt :They employed larger sample sizes, more valid fertile window estimates (validated with urine tests of the luteinizing hormone, LH, which peaks shortly before ovulation), within-subjects designs, steroid hormone assays, and employing Open Science practices. Interestingly, the vast majority of these newer studies found no compelling evidence for ovulatory cycle shifts in mate preferences for men‘s faces (Dixson et al., 2018; Jones et al., 2018a; Marcinkowska et al., 2018a, 2018b), bodies (Jünger et al., 2018a; Marcinkowska et al., 2018a, 2018b; van Stein et al., 2019), voices (Jünger et al., 2018b) and behaviors (Stern et al., 2020). However, some of these studies presented evidence for shifts in mate attraction instead of mate preferences, in that all men were evaluated as being a little more attractive when fertile, independent of male characteristics.
Challenges to both reliability and validity of masculinity-preference measures in menstrual-cycle-effects research
2020, CognitionCitation Excerpt :Further studies have investigated the fertility effect on masculinity preference since these meta-analysis studies. Little and Jones (2012) and Dixson et al. (2018) found significant fertility shifts for masculinity preferences; however, some have failed to find a fertility shift (e.g., Jones et al., 2018; Marcinkowska, Galbarczyk, & Jasienska, 2018 and Zietsch, Lee, Sherlock, & Jern, 2015). Jones, Hahn, and DeBruine (2018) provide a recent review of the topic and some of the methodological issues associated with finding a fertility shift for masculinity preferences, although they do not consider the two main methodological issues raised here: that of the validity and reliability of the masculinity preference tasks typically employed.
Assessing the evidentiary value of secondary data analyses: A commentary on Gangestad, Dinh, Grebe, Del Giudice, and Thompson (2019)
2019, Evolution and Human BehaviorDifferential effects of resource scarcity and pathogen prevalence on heterosexual women's facial masculinity preferences
2021, Evolutionary Human Sciences