Mate preferences and choices for facial and body hair in heterosexual women and homosexual men: influence of sex,population, homogamy,and imprinting-like effect

Recent research has reported that male body and facial hair influence women's mate preferences. However, it is not clear whether such preferences are typical for women or for individuals who prefer males as sexual partners. Here we explored body and facial hair in preferred and actual partners among men and women who prefer men as sexual partners. Including homosexual individuals provides a unique opportunity to investigate whether evolved mating psychologies are specific to the sex of the individual or sex of the partner. Based on an online survey of 1577 participants from Brazil and the Czech Republic, we found that, on average, homosexual men preferred hairier stimuli than heterosexual women, supporting past findings that homosexual men have strong preferences for masculine traits. Preferences for facial and body hair appear to be influenced less by sex of the preferred partner than sex of the individual, pointing to a possible sex-specific mating psychology. Further, Brazilians preferred bigger beards than Czechs, which was positively associated with the self-reported amount of beardedness in Brazil, suggesting that familiarity effects underpin cross-cultural differences in preferences for facial hair. Moreover, homosexual men preferred a self-similar degree of beardedness, and Czech women preferred a similar degree of beardedness as their fathers had during their childhood. However, these effects were not associated with the level of facial hair in their actual partners; in general, mate preferences and actual mate choices for facial and body hair differed. Thus, individual differences in some self-reported characteristics, cultural factors, and aspects of personal experience may modulate differences in preferences for masculine traits.     

Sexual dimorphism in epicuticular compounds despite similar sexual selection in sex role‐reversed seed beetles

Sexual selection imposed by mating preferences is often implicated in the evolution of both sexual dimorphism and divergence between species in signalling traits. Epicuticular compounds (ECs) are important signalling traits in insects and show extensive variability among and within taxa. Here, we investigate whether variation in the multivariate EC profiles of two sex role‐reversed beetle species, Megabruchidius dorsalis and Megabruchidius tonkineus, predicts mate attractiveness and mating success in males and females. The two species had highly distinct EC profiles and both showed significant sexual dimorphism in ECs. Age and mating status in both species were also distinguishable by EC profile. Males and females of both species showed significant association between their EC profile and attractiveness, measured both as latency to mating and as success in mate‐choice trials. Remarkably, the major multivariate vector describing attractiveness was correlated in both species, both sexes, and in both choice and no‐choice experiments such that increased attractiveness was in all cases associated with a similar multivariate modification of EC composition. Furthermore, in both sexes this vector of attractiveness was associated with more male‐like EC profiles, as well as those characterizing younger and nonvirgin individuals, which might reflect a general preference for individuals of high condition in both sexes. Despite significant sexual selection on EC composition, however, we found no support for the proposition that sexual selection is responsible for divergence in ECs between these species.     

Condition-dependent calibration of men’s uncommitted mating orientation: evidence from multiple samples

Physical strength and physical attractiveness are both hypothesized as indicators of overall phenotypic condition in humans. Strategic Pluralism Theory (Gangestad & Simpson, 2000) predicts that men’s orientation toward uncommitted mating is facultatively calibrated (i.e. contingently adjusted over ontogeny) in response to condition-dependent physical features, such as strength and attractiveness. Herein, we suggest that previous research bearing on this hypothesis has been limited because (a) researchers have often neglected to distinguish between mating orientations and past sexual behavior and (b) sample sizes have not always been large enough to reliably detect correlations of moderate magnitude. To address these issues and extend previous findings, we present aggregated data from three independent samples of young adults that permit us to examine multiple measures of physical strength and attractiveness in relation to uncommitted mating orientation, committed mating orientation, and past sexual behavior. As predicted, meta-analyses across samples demonstrated that strength and attractiveness were positively correlated with men’s (but not women’s) uncommitted mating orientation (but not committed mating orientation). In addition, strength (in men only) and attractiveness (in both sexes) positively predicted participants’ number of past sex partners. Moreover, path analyses demonstrated that the association of men’s physical features with their number of sex partners was mediated via uncommitted mating orientation. These results (a) provide the most extensive support to date for the hypothesis that men’s uncommitted mating orientation is calibrated to condition-dependent features and (b) clarify the sex-specific functional links among physical features, mating orientations and sexual behavior.     

Low-investment copulation: Sex differences in motivations and emotional reactions

Samples of male (n = 113) and female (n = 175) college students were surveyed. Majorities of both sexes agreed with statements indicating that males' sexual attractiveness varied more than females' sexual attractiveness as a function of their status. Subjects who reported more sex partners and a greater aversion to sexual monogamy were slightly more likely to agree that they tested their partners to see how far they could push them. Interviews with highly sexually active females (n = 32) and males (n = 24) indicated that low-investment copulation and lack of control over the sexual access-investment ratio caused even women with very permissive attitudes and multiple sex partners to develop an aversion to low-investment copulation. Three levels were identified in this process. The techniques that women with multiple partners used to deal with their feelings are described. Females tested their partners for ability and willingness to invest. Males tested for opportunities to reduce investment and pursue other women. High status, for example athletic stardom, transformed males' sexual attractiveness to women and numbers of sex partners. Results were consistent with the view that the emotional-motivational mechanisms that moderate sexual arousal and attraction are sexually dimorphic.     

How conception risk affects competition and cooperation with attractive women and men

We investigated competition and cooperation for resources across the menstrual cycle in the context of bargaining games. Although bargaining has been studied within an evolutionary framework, little attention has been paid specifically to the role of mating motives in economic behavior. To investigate how motives related to reproductive success affect bargaining, participants at high or low risk for conception or who were on oral contraceptives played ultimatum and dictator games with partners who varied in sex and facial attractiveness. In ultimatum games, women in the fertile phase were more competitive over resources with attractive women than with less attractive women. Intrasexual competition was not observed in dictator games. Women were more cooperative with attractive men than with less attractive men in both games, regardless of fertility status. Low fertility women were more cooperative with attractive members than with less attractive members of both sexes in both games. Results support the view that, during periods of high fertility, when women are most intrasexually competitive for mates, withholding resources from potential rivals would enable women to gain the means to enhance their attractiveness and weaken competitors' abilities to do the same at a time when relative advantages in appearance are most crucial to reproductive success. The lack of a fertility effect for cooperation with potential mates supports the view that displays of generosity accrue benefits for women across the cycle in their efforts to attract men who will invest in relationships.     

Human vocal behavior within competitive and courtship contexts and its relation to mating success

Beyond the linguistic content of their speech, speakers of both sexes convey diverse biological and psychosocial information through their voices, which are important when assessing potential mates and competitors. However, studies investigating the relationships between mating success and acoustic inter-individual differences are scarce. In this study, we investigated such relationships in both sexes in courtship and competitive interactions—as they correspond to the two different types of sexual selection—using an experimental design based on a simulated dating game. We assessed which type of sexual selection best predicted mating success, here defined as the self-reported number of sexual partners within the past year. Our results show that only acoustic inter-individual differences in the courtship context for both men and women predicted their mating success. Men displaying faster articulation rate and louder voices reported significantly more sexual partners; in contrast, men displaying higher intonation reported a greater negative effect of roughness and breathiness on their mating success. Women who displayed relatively less breathy voices and shorter speech duration reported significantly fewer sexual partners. These novel findings are discussed in light of the mate choice context and the relative contribution of both types of sexual selection shaping acoustic features of speech.     

Foraging for mates in the hyperparasitic wasp, Dendrocerus carpenteri: impact of unfavourable weather conditions and parasitoid age

Males of the aphid hyperparasitoid Dendrocerus carpenteri (Curtis) were attracted by a sex pheromone released by conspecific females. The intensity of this cue, and thus female attractiveness, depended both on the female's mating status and her age. Only virgin females younger than 2 h were consistently recognized as mates by foraging males. Male age did not influence foraging and mating success. Empty mummies, from which females had emerged within the previous 10 min were attractive to males and examined intensively. Rain reduced the searching success of males, although the host plant Vicia faba provided sheltered places. Wind did not reduce mating success but prevented both sexes from leaving the host plant. Since the time of female attractiveness seems to be very limited, wind may have an enormous effect on the mating success of D. carpenteri in the field and thus on the population dynamics of this species. Received: 5 October 1998 / Accepted: 16 December 1998     

Self-control and honesty depend on exposure to pictures of the opposite sex in men but not women

Research has shown that viewing stimuli that induce mating or sex motivation can push men towards greater impulsivity, a manifestation of lower self-control. Recent advances in research on the connection between self-control and moral behavior indicate that low self-control is associated with increased dishonesty. From an evolutionary perspective, when mating motivation is activated, men may behave in dishonest ways by projecting characteristics in line with women's mate preferences to enhance their sexual attractiveness. We tested the possibility that exposure to pictures of sexually appealing women would engender lower self-control, leading men to behave dishonestly. The results showed that a state of lower self-control was observed in males who viewed women rated high on sexual attractiveness but not in males who viewed women rated low on sexual attractiveness or in females who viewed men (Experiment 1). Compared with control participants, male participants exposed to pictures of sexy women were less likely to return excess money received for participating (Experiment 2) and more likely to cheat in a matrix task (Experiments 3 and 4). State self-control mediated the link between exposure to sexual stimuli and dishonest behavior in men (Experiments 2 and 4). For men whose mating motivation is heightened by exposure to sexual stimuli, dishonesty appears to be a tactic for projecting characteristics preferred by women (e.g., large economic resources).     

Universal sex differences in online advertisers age preferences: comparing data from 14 cultures and 2 religious groups

The search for a potential partner has been aided over recent years by the widespread use of online dating sites and this process of relationship formation has conveniently presented an ideal opportunity for researchers to analyze human mating desires and to compare evolutionary and social constructivist based hypotheses. One such aspect of human mating behaviour yet to be thoroughly explored using access to online dating advertisements is the idealized age desired by each sex when considering a possible relationship. This study accessed minimum (youngest age considered) and maximum (oldest age considered) age preferences from 14 separate cultures and two religious groups from both sexes at ages 20, 25, 30, 35, 40, 45, and 50 years. The results showed that overall there was a growing disparity between males own age and preferred age of partner as males themselves aged (as indicated by greater effect sizes with advertisers age), with females showing a pattern for preferences around their own age or older. Females did not express an age preference for males younger than male's age preferences for females at any advertiser's age. On only three occasions were there no age differences between the sexes in their desire to initiate a relationship with the opposite sex. The results were clearly concurrent with earlier findings supportive of evolutionary or adaptationist interpretations. Neither a random pattern of age preferences more consistent with an arbitrary norms prediction, nor clear evidence for toy boy proclivities in females or males was found. Future studies utilizing the methodology used in this study to examine other human mating decision making processes are proposed.     

A sex-specific trade-off between mating preferences for genetic compatibility and body size in a cichlid fish with mutual mate choice

Mating preferences for genetic compatibility strictly depend on the interplay of the genotypes of potential partners and are therein fundamentally different from directional preferences for ornamental secondary sexual traits. Thus, the most compatible partner is on average not the one with most pronounced ornaments and vice versa. Hence, mating preferences may often conflict. Here, we present a solution to this problem while investigating the interplay of mating preferences for relatedness (a compatibility criterion) and large body size (an ornamental or quality trait). In previous experiments, both sexes of Pelvicachromis taeniatus, a cichlid fish with mutual mate choice, showed preferences for kin and large partners when these criteria were tested separately. In the present study, test fish were given a conflicting choice between two potential mating partners differing in relatedness as well as in body size in such a way that preferences for both criteria could not simultaneously be satisfied. We show that a sex-specific trade-off occurs between mating preferences for body size and relatedness. For females, relatedness gained greater importance than body size, whereas the opposite was true for males. We discuss the potential role of the interplay between mating preferences for relatedness and body size for the evolution of inbreeding preference.     

Reproductive strategy, sexual development and attraction to facial characteristics

Sexual reproduction strategies vary both between and within species in the level of investment in offspring. Life-history theories suggest that the rate of sexual maturation is critically linked to reproductive strategy, with high investment being associated with few offspring and delayed maturation. For humans, age of puberty and age of first sex are two developmental milestones that have been associated with reproductive strategies. Stress during early development can retard or accelerate sexual maturation and reproduction. Early age of menarche is associated with absence of younger siblings, absence of a father figure during early life and increased weight. Father absence during early life is also associated with early marriage, pregnancy and divorce. Choice of partner characteristics is critical to successful implementation of sexual strategies. It has been suggested that sexually dimorphic traits (including those evident in the face) signal high-quality immune function and reproductive status. Masculinity in males has also been associated with low investment in mate and offspring. Thus, women's reproductive strategy should be matched to the probability of male investment, hence to male masculinity. Our review leads us to predict associations between the rate of sexual maturation and adult preferences for facial characteristics (enhanced sexual dimorphism and attractiveness). We find for men, engaging in sex at an early age is related to an increased preference for feminized female faces. Similarly, for women, the earlier the age of first sex the greater the preference for masculinity in opposite-sex faces. When we controlled sexual dimorphism in male faces, the speed of sexual development in women was not associated with differences in preference for male facial attractiveness. These developmental influences on partner choice were not mediated by self-rated attractiveness or parental relationships. We conclude that individuals assort in preferences based on the rapidity of their sexual development. Fast developing individuals prefer opposite-sex partners with an increased level of sexually dimorphic facial characteristics.     

Mate Choice Copying in Humans

There is substantial evidence that in human mate choice, females directly select males based on male display of both physical and behavioral traits. In non-humans, there is additionally a growing literature on indirect mate choice, such as choice through observing and subsequently copying the mating preferences of conspecifics (mate choice copying). Given that humans are a social species with a high degree of sharing information, long-term pair bonds, and high parental care, it is likely that human females could avoid substantial costs associated with directly searching for information about potential males by mate choice copying. The present study was a test of whether women perceived men to be more attractive when men were presented with a female date or consort than when they were presented alone, and whether the physical attractiveness of the female consort affected women’s copying decisions. The results suggested that women’s mate choice decision rule is to copy only if a man’s female consort is physically attractive. Further analyses implied that copying may be a conditional female mating tactic aimed at solving the problem of informational constraints on assessing male suitability for long-term sexual relationships, and that lack of mate choice experience, measured as reported lifetime number of sex partners, is also an important determinant of copying.     

Male facial attractiveness and masculinity may provide sex‐ and culture‐independent cues to semen quality

Phenotype‐linked fertility hypothesis (PLFH) predicts that male secondary sexual traits reveal honest information about male fertilization ability. However, PLFH has rarely been studied in humans. The aim of the present study was to test PLFH in humans and to investigate whether potential ability to select fertile partners is independent of sex or cultural background. We found that on the contrary to the hypothesis, facial masculinity was negatively associated with semen quality. As increased levels of testosterone have been demonstrated to impair sperm production, this finding may indicate a trade‐off between investments in secondary sexual signalling (i.e. facial masculinity) and fertility or status‐dependent differences in investments in semen quality. In both sexes and nationalities (Spanish and Colombian), ranked male facial attractiveness predicted male semen quality. However, Spanish males and females estimated facial images generally more attractive (gave higher ranks) than Colombian raters, and in both nationalities, males gave higher ranks than females. This suggests that male facial cues may provide culture‐ and sex‐independent information about male fertility. However, our results also indicate that humans may be more sensitive to facial attractiveness cues within their own populations and also that males may generally overestimate the attractiveness of other men to females.     

The effects of female control of resources on sex-differentiated mate preferences

A number of sex differences in mate preferences have been reported across cultures. Women prefer partners who are older than them whereas men prefer partners who are younger than them. Women have stronger preferences for resource-acquisition characteristics whereas men have stronger preferences for physical attractiveness. Recently, studies have reported shifts in female preferences with increasing female empowerment and associated female attitudes. Other studies, however, report opposite effects of female wealth and income. In this study, we investigated the effects of female control of the resources necessary to raise offspring successfully on mate preferences. We developed measures of resource control at the level of the individual and investigated relationships between these and mate preferences using an internet survey. Resource control was associated with preferences for physical attractiveness over good financial prospects and greater maximum partner age tolerated. Resource control, however, was also associated with tolerance of younger partners. The results implicate the role of constraints on female access to and control of resources in sex-differentiated mate preferences and highlight differences between resource control and wealth.     

Effect of the mating plug on female chemical attractiveness and mating acceptance in a scorpion

After mating, females may experience a decline in sexual receptivity and attractiveness that may be associated with changes in the production and emission of sex pheromones. In some cases, these changes are produced by chemical substances or structures (e.g., mating plugs) produced by males as a strategy to avoid or reduce sperm competition. In scorpions, sex pheromones may be involved in finding potential mates and starting courtship. Here, we tested the hypothesis that the males of Urophonius brachycentrus, a species that produces a mating plug, use chemical communication (sex pheromones) to detect, localize, and discriminate females according to their mating status (virgin or inseminated), aided by chemical signaling. We also explored the effect of extracting of the mating plug on chemical communication and mating acceptance. We used Y‐maze olfactometers with different stimuli to analyze male choice and exploration time. To evaluate mating acceptance, we measured the attractiveness and receptivity of females of different mating status. We found that chemical communication occurs through volatile pheromones, but not contact pheromones. Males equally preferred sites with virgin or inseminated females with removed mating plug. In turn, females with these mating statuses were more attractive and receptive for males than inseminated females. This study suggests that the mating plug significantly affects female chemical attractiveness with an effect on volatile pheromones and decreasing sexual mating acceptance of females. The decline in the female's sexual receptivity is a complex process that may respond to several non‐exclusive mechanisms imposed by males and strategically modulated by females.     

Variation between and within the sexes in body size preferences

Although it is often assumed that males and females have mating preferences for larger individuals of the other sex, potential underlying differences between male and female preferences for body size are not commonly investigated. Here, sexual differences in body size preferences are examined in the poeciliid fish, Brachyrhaphis rhabdophora. Females preferred larger males to smaller males, but preference did not appear to be affected by female size. One population-level analysis for males did not indicate an overall preference for larger females. A closer examination, however, revealed an effect of male size on preference; larger males preferred larger females, while smaller males preferred smaller females. It appears then that females, regardless of size, share a preference for large males, but males differ in their behaviour, depending on their body size. In addition, while the degree of difference in size between paired females did not appear to affect male preference, the degree of difference in size between paired males strongly affected female preference; the greater the difference, the more strongly females preferred the larger male. Thus, intersexual selection is found to operate in both sexes, but how it operates appears to differ. Intrasexual and intersexual differences in mating behaviour may be missed when evaluating population-wide preferences. That is, there can be underlying differences in how the sexes respond and the consequences of such differences should be considered when investigating mate choice. The results are considered in terms of the evolution of mating preferences, alternative mating strategies, assortative mating, the maintenance of trait variation in a population, and current methods to evaluate mating preferences.     

Handsome wants as handsome does: physical attractiveness and gender differences in revealed sexual preferences

In this article I evaluate the effect of physical attractiveness on young adults' sexual and romantic outcomes to reveal gender differences in acted preferences. Using data from the National Longitudinal Study of Adolescent Health (Add Health), a probability sample of young adults (n = 14,276), I investigate gender differences in desired sexual partner accumulation, relationship status, and timing of sexual intercourse. I find gender differences in sexual and romantic strategies consistent with those predicted by the double standard of sexuality and evolutionary theory. Specifically, compared to men, women pursue more committed relationships, fewer sexual partners, and delayed sexual intercourse.     

Choice of companions in social play in piglets

Play activity differences between sexes have been predicted in sexually dimorphic species. A non-random composition of pairs of players in social play has also been suggested. In order to test these proposals in piglets, two experiments were set up on a focal-animal basis.In the first trial, social play as observed in two sets of 16 weaned piglets, from 4 litters of 8 piglets, each with an equal number of males and females. A total of 133 and 101 plays, respectively, were recorded and analysed using a log-linear model including the sex and litter of each player and their interactions. The main results show: (a) a greater play activity in males than in females; (b) more play between partners of the same sex than expected assuming statistical independence; (c) more play between partners born in the same litter than expected assuming statistical independence.The role of the pheromones segregated by submaxillary salivary glands in the sexual recognition evidenced in the first experiment was tested in the second trial. Two sets of 16 piglets, coming from 16 different litters, were observed; one of them as control and the other with 8 males whose glands had been removed and 8 normal females. The analysis of 230 plays recorded confirms the results of the first trial concerning sex and does not show significant differences either in the total number of observed plays or in the preference for partners of the same sex between sets, implying a recognition mechanism other than that of these pheromones.The observed sexual dimorphism in play activity as well as the sex and littermate preferences are in agreement with the hypothesis which assigns adaptive values to these social plays.