Scarcity of female mates predicts regional variation in men’s and women’s sociosexual orientation across US states

Previous studies have linked regional variation in willingness to engage in uncommitted sexual relationships (i.e., sociosexual orientation) to many different socio-ecological measures, such as adult sex ratio, life expectancy, and gross domestic product. However, these studies share a number of potentially serious limitations, including reliance on a single dataset of responses aggregated by country and a failure to properly consider intercorrelations among different socio-ecological measures. We address these limitations by (1) collecting a new dataset of 4,453 American men’s and women’s sociosexual orientation scores, (2) using multilevel analyses to avoid aggregation, and (3) deriving orthogonal factors reflecting US state-level differences in the scarcity of female mates, environmental demands, and wealth. Analyses showed that the scarcity of female mates factor, but not the environmental demand or wealth factors, predicted men’s and women’s sociosexual orientation. Participants reported being less willing to engage in uncommitted sexual relationships when female mates were scarce. These results highlight the importance of scarcity of female mates for regional differences in men’s and women’s mating strategies. They also suggest that effects of wealth-related measures and environmental demands reported in previous research may be artifacts of intercorrelations among socio-ecological measures or, alternatively, do not necessarily generalize well to new datasets

Perceiving infant faces

Evolutionary theories have long been used to generate testable predictions about responses to adult facial cues in the contexts of mate choice, cooperation, and intrasexual competition, among others. More recently, researchers have also used evolutionary theories to guide research on responses to infant facial cues. Here we review some of this work, focusing on research investigating hormonal regulation of responses to infant facial cuteness and the role of kinship cues in perceptions of infant faces. These studies suggest that sex hormones have dissociable effects on the reward value of and perceptual sensitivity to infant facial cuteness. They also suggest that attitudes and behavior toward infants displaying cues of kinship are complex processes influenced by individual differences

Reported maternal tendencies predict the reward value of infant facial cuteness, but not cuteness detection

The factors that contribute to individual differences in the reward value of cute infant facial characteristics are poorly understood. Here we show that the effect of cuteness on a behavioral measure of the reward value of infant faces is greater among women reporting strong maternal tendencies. By contrast, maternal tendencies did not predict women’s subjective ratings of the cuteness of these infant faces. These results show, for the first time, that the reward value of infant facial cuteness is greater among women who report being more interested in interacting with infants, implicating maternal tendencies in individual differences in the reward value of infant cuteness. Moreover, our results indicate that the relationship between maternal tendencies and the reward value of infant facial cuteness is not due to individual differences in women’s ability to detect infant cuteness. This latter result suggests that individual differences in the reward value of infant cuteness are not simply a byproduct of low cost, functionless biases in the visual system

Sex ratio influences the motivational salience of facial attractiveness

The sex ratio of the local population influences mating-related behaviours in many species. Recent experiments show that male-biased sex ratios increase the amount of financial resources men will invest in potential mates, suggesting that sex ratios influence allocation of mating effort in humans. To investigate this issue further, we tested for effects of cues to the sex ratio of the local population on the motivational salience of attractiveness in own-sex and opposite-sex faces. We did this using an effort-based key-press task, in which the motivational salience of facial attractiveness was assessed in samples of faces in which the ratio of male to female images was manipulated. The motivational salience of attractive opposite-sex, but not own-sex, faces was greater in the own-sex-biased (high competition for mates) than in the opposite-sex-biased (low competition for mates) condition. Moreover, this effect was not modulated by participant sex. These results present new evidence that sex ratio influences human mating-related behaviours. They also present the first evidence that the perceived sex ratio of the local population may modulate allocation of mating effort in women, as well as men

Face and voice attractiveness judgments change during adolescence

Attractivenessjudgments are thought to underpin adaptive mate choice decisions. We investigated how these judgmentschange during adolescence when mate choice is becoming relevant. Adolescents aged 11–15 evaluated faces and voices manipulated along dimensions that affect adults' judgments of attractiveness and that are thought to cue mate value. Facial stimuli consisted of pairs of faces that were more or less average, more or less feminine, or more or less symmetric. The adolescents selected the more average, symmetric, and feminine faces as more attractive more often than chance, but judgments of some facial traits differed significantly with rater age and sex, indicating a role of development in judgments of facial cues. Vocal stimuli consisted of pairs of voices manipulated to raise or lower perceived pitch. The older but not younger girls selected the lower-pitched male voices as more attractive at rates above chance, while the younger but not older boys selected the higher-pitched female voices as more attractive. Controlling for rater age, increased pubertal development was associated with increased selection of lower-pitched boys' voices by girls and decreased selection of feminized male faces by boys. Our results are the first to demonstrate that adolescents show somewhat similar attractivenessjudgments to adults in age-matched stimuli and that age, sex, and pubertal development have measurable effects on adolescents' attractivenessjudgments. They suggest that attractivenessjudgments in humans, at least for some traits, are facultatively calibrated to the individual's life stage, only reaching adult values upon sexual maturity when mate choice decisions become relevant

Do partnered women discriminate men's faces less along the attractiveness dimension?

Romantic relationships can have positive effects on health and reproductive fitness. Given that attractive potential alternative mates can pose a threat to romantic relationships, some researchers have proposed that partnered individuals discriminate opposite-sex individuals less along the physical attractiveness dimension than do unpartnered individuals. This effect is proposed to devalue attractive (i.e., high quality) alternative mates and help maintain romantic relationships. Here we investigated this issue by comparing the effects of men's attractiveness on partnered and unpartnered women's performance on two response measures for which attractiveness is known to be important: memory for face photographs (Study 1) and the reward value of faces (Study 2). Consistent with previous research, women's memory was poorer for face photographs of more attractive men (Study 1) and more attractive men's faces were more rewarding (Study 2). However, in neither study were these effects of attractiveness modulated by women's partnership status or partnered women's reported commitment to or happiness with their romantic relationship. These results do not support the proposal that partnered women discriminate potential alternative mates along the physical attractiveness dimension less than do unpartnered women

Voice pitch preferences of adolescents: Do changes across time indicate a shift towards potentially adaptive adult-like preferences?

An evolutionary approach to attractiveness judgments emphasises that many human trait preferences exist in order to assist adaptive mate choice. Here we test an adaptive development hypothesis, whereby voice pitch preferences indicating potential mate quality might arise or strengthen significantly during adolescence (when mate choice becomes adaptive). We used a longitudinal study of 250 adolescents to investigate changes in preference for voice pitch, a proposed marker of mate quality. We found significantly stronger preferences for lower-pitched opposite-sex voices in the older age group compared with the younger age group (using different sets of age-matched stimuli), and marginally increased preferences for lower-pitched opposite-sex voices comparing within-participant preferences for the same set of stimuli over the course of 1 year. We also found stability in individual differences in preferences across adolescence: controlling for age, the raters who had stronger preferences than their peers for lower pitched voices when first tested, retained stronger preferences for lower-pitched voices relative to their peers about 1 year later. Adolescence provides a useful arena for evaluating adaptive hypotheses and testing the cues that might give rise to adaptive behaviour

Exploring How Faces Reveal Our Ethnicity

The human face varies with ethnicity as well as individually within any ethnotype. The ethnicvariation of the human face is seldom explicitly addressed in education. It would be of great value to foster the appreciation of the face as telling the story of the commonality of all of humankind and the diversity in our global distribution. Faces tell about origins and cultures. The language with which a face tells this story should be taught. It is a language not of words but of shapes, specifically three-dimensional shapes. Modern technology enables immersive visualization of three-dimensional shape in compelling ways that facilitate our learning a language with which to describe faces. An interactive animation framework is introduced that allows exploration of the space of ethnic variation via a set of intuitive, human understandable, facial shape properties. Parametric variation in these properties make explicit how our faces reveal our ethnicity

A sex difference in the context-sensitivity of dominance perceptions

Although dominance perceptions are thought to be important for effective social interaction, their primary function is unclear. One possibility is that they simply function to identify individuals who are capable of inflicting substantial physical harm, so that the perceiver can respond to them in ways that maximize their own physical safety. Another possibility is that they are more specialized, functioning primarily to facilitate effective direct (i.e., violent) intrasexual competition for mates, particularly among men. Here we used a priming paradigm to investigate these two possibilities. Facial cues of dominance were more salient to women after they had been primed with images of angry men, a manipulation known to activate particularly strong self-protection motivations, than after they had been primed with images of angry women or smiling individuals of either sex. By contrast, dominance cues were more salient to men after they had been primed with images of women than when they had been primed with images of men (regardless of the emotional expressions displayed), a manipulation previously shown to alter men's impressions of the sex ratio of the local population. Thus, men's dominance perceptions appear to be specialized for effective direct competition for mates, while women's dominance perceptions may function to maximize their physical safety more generally. Together, our results suggest that men's and women's dominance perceptions show different patterns of context-sensitivity and, potentially, shed new light on the routes through which violence and intrasexual competition have shaped dominance perceptions

What's a face worth: Noneconomic factors in game playing

Where behavior defies economic analysis, one explanation is that individuals consider more than the immediate payoff. We present evidence that noneconomic factors influence behavior. Attractiveness influences offers in the Ultimatum and Dictator Games. Facial resemblance, a cue of relatedness, increases trusting in a two-node trust game. Only by considering the range of possible influences will game-playing behavior be explained