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Ovulatory cycle shifts in women’s mate preferences have been documented for several physical and behavioral traits. Research suggests that, at peak fertility, women tend to prefer men with characteristics that reflect good genes for short-term sexual relationships. However, existing findings have been criticized for methodological flexibility and failing attempts to replicate core results. In a large (N=157), pre-registered, within-subject study spanning two ovulatory cycles, we investigated cycle shifts in women’s mate preferences for masculine bodies. Using a large set of natural stimuli, we found that when fertile, women’s ratings of male bodies increased for sexual as well as for long-term attractiveness. Both effects were partially mediated by the estradiol-to-progesterone-ratio. Furthermore, moderation analyses revealed that both shifts were only evident in women in relationships, but not in singles. Contrary to previous findings, male masculine traits did not interact with cycle phase to predict attraction, indicating that women’s preferential priorities do not shift. Taken together, our results do not support women’s mate preference shifts, as assumed by the good genes ovulatory shift hypothesis, but are consistent with shifting motivational priorities throughout the cycle. Implications of these results for female estrus theories and methodological recommendations for future research are discussed.
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Objective: To explore associations between the 5-factor model (FFM; neuroticism, extraversion, openness/intellect, agreeableness, and conscientiousness), personality traits, and measures of whole-brain integrity in a large sample of older people, and to test whether these associations are mediated by health-related behaviors. Method: Participants from the Lothian Birth Cohort 1936 completed the International Personality Item Pool measure, a 5-factor public-domain personality measure (http://ipip.ori.org), and underwent a structural magnetic resonance brain scan at the mean age of 73 years, yielding 3 measures of whole brain integrity: average white matter fractional anisotropy (FA), brain-tissue loss, and white matter hyperintensities (N = 529 to 565). Correlational and mediation analyses were used to test the potential mediating effects of health-related behaviors on the associations between personality and integrity. Results: Lower conscientiousness was consistently associated with brain-tissue loss (β = −0.11, p < 0.01), lower FA (β = 0.16, p < 0.001) and white matter hyperintensities (β = −0.10, p < 0.05). Smoking, alcohol consumption, diet, physical activity, body mass index and a composite health-behavior variable displayed significant associations with measures of brain integrity (range of r = 0.10 to 0.25). The direct effects of conscientiousness on brain integrity were mediated to some degree by health behaviors, with the proportions of explained direct effects ranging from 0.1% to 13.7%. Conclusion: Conscientiousness was associated with all 3 measures of brain integrity, which we tentatively interpret as the effects of personality on brain aging. Small proportions of the direct effects were mediated by individual health behaviors. Results provide initial indications that lifetime stable personality traits may influence brain health in later life through health-promoting behaviors.
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Sir – In a letter to the Editor, D. Oliva has raised the hypothesis that there might be a guiding thread through pheromone communication from unicellular organisms up to humans, which may serve as an expla- nation for human homosexual orientation. Although we do not want to reject this hypothesis in its entirety, as links between olfactory signals and human sexual ori- entation remain poorly understood, the argument seem to be too simplistic in light of evolutionary adaptation- ism and neurobiological research, and requires further investigation and discussion. Our reply should not be regarded as criticism, but rather to encourage further academic discussion.
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Previous research has suggested that offspring sex ratio may be influenced by the actions of prenatal sex steroids, principally androgens. The relative length of the second (index finger) to the fourth digit (ring finger) has been reported to be a proxy to prenatal testosterone levels. This trait is sexually dimorphic, such that males display a significantly lower 2D:4D ratio (indicating higher testosterone exposure), and this dimorphism appears robust across different populations. We suggest that digit ratio (2D:4D) may form a useful marker to help explain variation in sex ratio and sociosexuality.
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Im Tierreich ist olfaktorische Kommunikation, besonders bei der Partnerwahl, weit verbreitet und mittlerweile gut studiert. Mit der wachsenden Anzahl an Studien über die biologischen Rahmenbedingungen/Mechanismen der Partnerwahl und der Entdeckung des Vomeronasalorgan (VNO) beim Menschen hat das wissenschaftliche Interesse an der Bedeutung des Körpergeruchs als mögliches Signalsystem in diesem Kontext deutlich zugenommen. Die Annahme, dass Menschen und andere Primaten vorwiegend visuell gesteuerte Lebewesen sind, die auch im Zuge der Partnerwahl hauptsächlich auf optische Reize angewiesen sind, musste in den letzten Jahren revidiert werden. Jüngste Studien zeigen, dass Pheromone (Geruchsbotenstoffe) eine wichtige Rolle in der Verhaltens- und Fortpflanzungsbiologie des Menschen spielen können, deuten aber auch darauf hin, dass manche Annahmen einer Modifikation bedürfen. Dieser Artikel gibt einen Überblick über die aktuellen Hypothesen und sog. Beweise für die Wirkung von menschlichen Pheromonen und diskutiert deren Bedeutung für das menschliche Sexualverhalten.
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Signaling mate quality through visual adornments is a common phenomenon in animals and humans. However, humans are probably the only species who applies artificial ornaments. Such deliberate alterations of the skin, e.g., tattoos and scarring patterns, have been discussed by researchers as potential handicap signals, but there is still very little information about a potential biological signaling value of body modification. In this study eye-tracking was employed to investigate the signaling value of tattoos and other body modification. Measurement of gaze duration of 50 individuals while watching plain, scarred, accessorized, and tattooed bodies of artificial human images indicated that participants looked significantly longer at tattooed than at scarred, accessorized, and plain bodies. Generally, male participants paid more attention to tattooed stimuli of both sexes. More detailed analyses showed that particularly female tattooed stimuli were looked at longer. These findings are discussed within an evolutionary framework by suggesting that tattoos might have some signaling value which influences the perception of both male and female conspecifics and may hence also affect mating decisions.
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According to evolutionary psychology, the preference for some facial characteristics reflects adaptations for mate choice because they signal aspects of mate quality. Although morphological features such as facial symmetry and sexually dimorphic traits have been studied extensively in recent years, little is known about skin condition in this context. The preferences for young and healthy looking skin could offer an explanation as to why women place such an importance on the condition of their skin and its refinement through e.g., cosmetic products. Recent research showed that facial skin colour distribution significantly influences the perception of age and attractiveness of female faces, independent of skin surface topography cues. However, the relative effect of skin colour distribution and topography cues on age and health perception remains to be investigated. We present data showing that both skin colour distribution and skin surface topography cues not only significantly influence the perception of female facial age and health but also convey differential information with regard to the strength of these effects. Our data indicate that skin surface topography cues account for a large proportion of variation in facial age perception, whereas skin colour distribution seems to be a stronger health cue.
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Neck circumference, measured as the distance around the neck, is a simple and timesaving screening measure to identify obesity in both men and women. It is positively correlated with the components of the metabolic syndrome and obstructive sleep apnea. Furthermore, neck circumference is positively associated with traditional anthropometric measures of body circumferences and indices, such as the body mass index and the waist-to-hip ratio, and other physiological and biochemical measures of cardiovascular risk. It is positively correlated with systolic and diastolic blood pressure, triglycerides and glucose levels and has been used as a clinical predictor of menstrual irregularity, hirsutism, infertility, and insulin resistance. This has led to and increased interest in this measure with regard to its usefulness in clinical and epidemiological studies, but also from biological studies, interested in the possibility of an early predisposition for cardiovascular risk through early sex-steroid exposure. This chapter briefly reviews the reported associations with neck circumference and suggests possible applications also in non-clinical studies.
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Background Visible facial skin condition in females is known to affect perception of age, health and attractiveness. Skin colour distribution in shape- and topography-standardized female faces, driven by localized melanin and haemoglobin, can account for up to twenty years of apparent age perception. Although this is corroborated by an ability to discern female age even in isolated, non-contextual skin images, a similar effect in the perception of male skin is yet to be demonstrated. Objectives To investigate the effect of skin colour homogeneity and chromophore distribution on the visual perception of age, health and attractiveness of male facial skin. Methods Cropped images from the cheeks of facial images of 160 Caucasian British men aged 10–70 years were blind-rated for age, health and attractiveness by a total of 308 participants. In addition, the homogeneity of skin images and corresponding eumelanin/oxyhaemoglobin concentration maps were analysed objectively using Haralick’s image segmentation algorithm. Results Isolated skin images taken from the cheeks of younger males were judged as healthier and more attractive. Perception of age, health and attractiveness was strongly related to melanin and haemoglobin distribution, whereby more even distributions led to perception of younger age and greater health and attractiveness. The evenness of melanized features was a stronger cue for age perception, whereas haemoglobin distribution was associated more strongly with health and attractiveness perception. Conclusions Male skin colour homogeneity, driven by melanin and haemoglobin distribution, influences perception of age, health and attractiveness.
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Women with higher-pitched voices and more feminine facial features are commonly judged as being more attractive than are women with lower-pitched voices and less feminine faces, possibly because both features are affected by (age-related) variations in endocrine status. These results are primarily derived from investigations of perceptions of variations in single-modality stimuli (i.e., faces or voices) in samples of young adult women. In the present study we sought to test whether male and female perceptions of women's voices affect visual representations of facial femininity. Eighty men and women judged voice recordings of 10 young girls (11–15 years), 10 adult women (19–28 years) and 10 peri-/post-menopausal women (50–64 years) on age, attractiveness, and femininity. Another 80 men and women were asked to indicate the face they think each voice corresponded to using a video that gradually changed from a masculine looking male face into a feminine looking female face. Both male and female participants perceived voices of young girls and adult women to be significantly younger, more attractive and feminine than those of peri-/post-menopausal women. Hearing young girls' and adult women's voices resulted in both men and women selecting faces that differed markedly in apparent femininity from those associated with peri-/post-menopausal women's voices. Voices of young girls had the strongest effect on visualizations of facial femininity. Our results suggest a cross-modal preference for women's vocal and facial femininity, which depends on female age and is independent of the perceiver's sex.
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Female hair color is thought to influence physical attractiveness, and although there is some evidence for this assertion, research has yet not addressed the question if and how physical damaging affects the perception of female hair color. Here we investigate whether people are sensitive (in terms of visual attention and age, health and attractiveness perception) to subtle differences in hair images of natural and colored hair before and after physical damaging. We tracked the eye-gaze of 50 men and 50 women aged 31–50 years whilst they viewed randomized pairs of images of 20 natural and 20 colored hair tresses, each pair displaying the same tress before and after controlled cuticle damage. The hair images were then rated for perceived health, attractiveness, and age. Undamaged versions of natural and colored hair were perceived as significantly younger, healthier, and more attractive than corresponding damaged versions. Visual attention to images of undamaged colored hair was significantly higher compared with their damaged counterparts, while in natural hair, the opposite pattern was found. We argue that the divergence in visual attention to undamaged colored female hair and damaged natural female hair and associated ratings is due to differences in social perception and discuss the source of apparent visual difference between undamaged and damaged hair.
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Women's preferences for putative cues of genetic quality in men's voices, faces, bodies, and behavioral displays are stronger during the fertile phase of the ovulatory cycle. Here we show that ovulatory cycle-related changes in women's attractiveness perceptions of male features are also found with dance movements, especially those perceived as highly masculine. Dance movements of 79 British men were recorded with an optical motion-capture system whilst dancing to a basic rhythm. Virtual humanoid characters (avatars) were created and converted into 15-second video clips and rated by 37 women on masculinity. Another 23 women judged the attractiveness of the 10 dancers who scored highest and those 10 who scored lowest on masculinity once in days of high fertility and once in days of low fertility of their ovulatory cycle. High-masculine dancers were judged higher on attractiveness around ovulation than on other cycle days, whilst no such perceptual difference was found for low-masculine dancers. We suggest that women may gain fitness benefits from evolved preferences for masculinity cues they obtain from male dance movements.
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In a study of degree of lower body symmetry in 73 elite Jamaican track and field athletes we show that both their knees and ankles (but not their feet) are–on average–significantly more symmetrical than those of 116 similarly aged controls from the rural Jamaican countryside. Within the elite athletes, events ranged from the 100 to the 800 m, and knee and ankle asymmetry was lower for those running the 100 m dashes than those running the longer events with turns. Nevertheless, across all events those with more symmetrical knees and ankles (but not feet) had better results compared to international standards. Regression models considering lower body symmetry combined with gender, age and weight explain 27 to 28% of the variation in performance among athletes, with symmetry related to about 5% of this variation. Within 100 m sprinters, the results suggest that those with more symmetrical knees and ankles ran faster. Altogether, our work confirms earlier findings that knee and probably ankle symmetry are positively associated with sprinting performance, while extending these findings to elite athletes.
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Suicide attacks and terrorism are characterized by cognitive simplicity, which is related to self-deception. In justifying violence in pursuit of ideologically and/or politically driven commitment, people with high religious commitment may be particularly prone to mechanisms of self-deception. Related megalomania and glorious self-perception are typical of self-deception, and are thus crucial in the emergence and expression of (suicide) terrorism.
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Objectives: Facial age, health, and attractiveness assessments play a major role in human social interaction and affect the way we perceive and think about others. Modern cosmetic dermatology provides a bewildering array of facial treatment procedures with botulinum toxin type A and dermal filler application being the most requested. The authors sought to determine the effect of facial rejuvenation procedures, such as application of incobotulinumtoxin A and dermal filler injections, on people's perception of age, health, and attractiveness. Methods: Ten women underwent three consecutive facial rejuvenation procedures with incobotulinumtoxin A, calcium hydroxylapatite, and a hyaluronic acid. Digital facial images were taken before treatment and after each subsequent treatment and presented to a total of 150 third-party assessors who judged the images for age, health, and attractiveness. Results: Each procedure was associated with a significant reduction in perceived age and an increase in perceived health and attractiveness compared with pre-treatment images. The effects were cumulative such that faces perceived as the youngest, healthiest, and most attractive had received all three treatments, followed in descending order by incobotulinumtoxin A and calcium hydroxylapatite treatment, and incobotulinumtoxin A alone. Conclusion: The authors demonstrate that naive judges are readily able to perceive the effect of nonsurgical facial rejuvenation procedures with incobotulinumtoxin A, calcium hydroxylapatite, and hyaluronic acid in terms of age, health, and attractiveness judgments. These effects were greatest when incobotulinumtoxin A and dermal filler treatments were combined.
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Objectives Men and women accurately assess male physical strength from facial and body morphology cues. Women's assessments of male facial attractiveness, masculinity, and dominance correlate positively with male physical strength. A positive relationship also has been reported between physical strength and attractiveness of men's dance movements. Here, we investigate men's and women's attractiveness, dominance, and strength assessments from brief samples of male gait. Methods Handgrip strength (HGS) was measured in 70 heterosexual men and their gait was motion-captured. Men and women judged 20 precategorized strong (high HGS) and weak (low HGS) walkers on attractiveness, dominance, and strength, and provided a measure of their own HGS. Results Both men and women judged strong walkers higher on dominance and strength than weak walkers. Women but not men judged strong walkers more attractive than weak walkers. These effects were independent of observers' physical strength. Conclusions Male physical strength is conveyed not only through facial and body morphology, but also through body movements. We discuss our findings with reference to studies suggesting that physical strength provides information about male quality in contexts of inter- and intrasexual selection.
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This is not a science book. It is a book about a scientist ’ s life, characterized by ups and downs. In this regard, Robert Trivers ’ s life is not unusual. However , the chal lenges he faced may have been special, as is his style in overcoming them. His life includes challenges he created for himself, that he is responsible for, and perhaps he is the only person who could cope with and survive them.
