Sex differences in morphological predictors of sexual behavior: Shoulder to hip and waist to hip ratios
Introduction
There is growing evidence that individual differences in digit ratios (Robinson & Manning, 2000) and fluctuating asymmetry (Thornhill & Gangestad, 1994) are correlated with differences in sexual behavior. Other morphological features show variance not only among individuals, but are sexually dimorphic. One such trait is the waist to hip ratio (WHR), the circumference of the waist relative to the hips. WHR is an indicator of a female's hormonal profile and reproductive status and is linked to such things as age, fecundity, and the capacity to sustain pregnancy and nurse a child (Singh, 1993). Another sexually dimorphic feature is shoulder to hip ratio (SHR), the circumference of the shoulders relative to the hips. Broad shoulders and narrow hips tend to be a masculine trait related to testosterone (Kasperk et al., 1997).
In the present study, we examined WHR and SHR and their relationship to different aspects of sexual behavior in males and females.
Section snippets
Methods
Undergraduate students (56 females and 60 males) from the State University of New York at Albany participated in this study, which was approved by the University Institutional Review Board. Mean age was 19.6 years (S.D.=2.8), range 18–44. Subjects were not informed about the purpose of the study.
Subjects first completed an anonymous questionnaire concerning their sexual history. Two subjects reported being homosexual, three had children, and four were married; each of these subgroups was too
Results
Male SHRs (M=1.18±0.071, range 1.03–1.40) significantly (t=10.41, P<.01) exceeded female SHRs (M=1.03±0.066, range 0.90–1.22). Here and subsequently, M signifies mean±standard deviation.
Male SHR was negatively correlated with reported ages of first masturbation and first sexual intercourse, and positively correlated with reported numbers of sex partners, EPC partners, and persons for whom one had been an EPC partner (Table 1). Female SHR was not significantly correlated with any sexual behavior
Discussion
We found striking differences between males and females in features of the shoulders, waist, and hips that predict different dimensions of sexual behavior. Since high SHR in men is linked to androgen, while female fertility is related to WHR, these features may be important parameters of mate choice. In fact, both SHR and WHR influence judgements of attractiveness Dijkstra & Buunk, 2001, Singh, 1993.
Female WHR conveys information about hormonal profile, reproductive maturity, fecundity, and
References (10)
- et al.
Sex differences in the jealousy-evoking nature of a rival's body build
Evolution and Human Behavior
(2001) - et al.
Women's lives viewed from an evolutionary perspective: I. Sexual histories, reproductive success, and demographic characteristics of a random sample of American women
Ethology and Sociobiology
(1985) - et al.
What distinguishes women with unusually high numbers of sex partners?
Evolution and Human Behavior
(1999) - et al.
The ratio of 2nd to 4th digit length and male homosexuality
Evolution and Human Behavior
(2000) - et al.
Patterns of sexual behavior
(1951)
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