جذابیت صورت نشان دهنده جنبه های مختلف "کیفیت" در زنان و مردان
کد مقاله | سال انتشار | تعداد صفحات مقاله انگلیسی |
---|---|---|
35621 | 2001 | 20 صفحه PDF |
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Evolution and Human Behavior, Volume 22, Issue 2, March 2001, Pages 93–112
چکیده انگلیسی
We explored the relationships between facial attractiveness and several variables thought to be related to genotypic and phenotypic quality in humans (namely fluctuating asymmetry (FA), body mass index (BMI), health, age). To help resolve some controversy around previous studies, we used consistent measurement and statistical methods and relatively large samples of both female (n=94) and male (n=95) subjects (to be evaluated and measured), and female (n=226) and male (n=153) viewers (to rate attractiveness). We measured the asymmetry of 22 traits from three trait families (eight facial, nine body and five fingerprint traits) and constructed composite asymmetry indices of traits showing significant repeatability. Facial attractiveness was negatively related to an overall asymmetry index in both females and males, with almost identical slopes. Female facial attractiveness was best predicted by BMI and past health problems, whereas male facial attractiveness was best predicted by the socioeconomic status (SES) of their rearing environment. Composite FA indices accounted for a small (<4%) but usually significant percentage of the variation in facial attractiveness in both sexes, when factors related to asymmetry were controlled statistically. We conclude that, although facial attractiveness is negatively related to developmental instability (as measured by asymmetry), attractiveness also signals different aspects of “quality” in the two sexes, independent of FA.
مقدمه انگلیسی
Humans prefer to associate with, date, and mate with facially attractive individuals Barber, 1995, Buss, 1994, Patzer, 1985 and Walster et al., 1966 and attractive people are considered to be more successful, interesting and intelligent than unattractive people (Dion, Berscheid, & Walster, 1972). But what is it that attractiveness signals to potential mates? Sexual selection theory predicts that individuals gain some aspect of quality for their offspring by mating with attractive individuals, either by obtaining good genes or getting a mate that will be a good parent (Andersson, 1994). Over the last 10 years, several studies have investigated the relation between attractiveness and the fluctuating asymmetry (FA) of body traits. FA, small deviations from perfect bilateral symmetry, is thought to be an index of underlying developmental instability (Palmer & Strobeck, 1986), and is thus expected to be an index of genetic quality (reviewed in Gangestad, 1993, Gangestad & Thornhill, 1997a and Thornhill & Gangestad, 1996). For example, individuals with low levels of facial (Rikowski & Grammer, 1999) and body asymmetry (Gangestad, Thornhill, & Yeo, 1994) seem to be most attractive and FA is lower in healthy people (Shackelford & Larsen, 1997) who are also considered more attractive (Grammer & Thornhill, 1994 and Shackelford & Larsen, 1999, but see Kalick, Zebrowitz, Langlois, & Johnson, 1998). Thus, attractiveness seems to be positively related to the degree to which an individual copes with stresses during development (i.e., developmental stability as revealed by FA). We assume that human assessment of physical attractiveness has evolved because attractiveness was related to some aspect of “quality” in ancestral environments (Gangestad et al., 1994). In the present study, we tested whether facial attractiveness signals “quality” in humans by examining how attractiveness is related to age, indices of health and the FA of physical traits. In conducting this study, we had three primary aims. First, we wanted to bring together in one study a methodology that uses a number of developmentally and quantitatively dissimilar traits to critically examine the prediction that attractiveness is negatively related to FA in humans. Second, we determined whether any other variables might be responsible for the apparent relationship between attractiveness and FA (e.g., body mass index or BMI, as suggested by Thornhill & Grammer, 1999). Third, we analyzed the attractiveness (to the opposite sex) of male and female faces separately, so we could compare the traits that attractiveness appears to signal. Our study responds to the scarcity of research measuring the FA of different kinds of traits by measuring a total of 22 traits comprising three trait families (eight facial, nine body and five fingerprint). Previous studies of attractiveness and FA have typically measured only one trait or a small family of traits: body asymmetry (e.g., length of digits, width of joints: Gangestad et al., 1994, Thornhill & Gangestad, 1994 and Thornhill et al., 1995) or facial asymmetry (e.g., asymmetry of nose and jaw: Grammer & Thornhill, 1994, Scheib et al., 1999 and Shackelford & Larsen, 1997). A notable exception to this single trait family approach is a recent study by Rikowski and Grammer (1999) that measured asymmetry in both facial and body traits of a mixed sex sample. Rikowski and Grammer found that facial asymmetry in males was significantly negatively related to their attractiveness, but they did not find any relationship between attractiveness and body asymmetry of males nor between attractiveness and asymmetry in any trait category of females. Each of the three trait families that we measured is developmentally different: facial traits develop throughout life and are considered by some to be secondary sexual traits Møller & Thornhill, 1998 and Thornhill & Grammer, 1999. In contrast, the body traits we measured (ankles, feet, fingers, wrists, ears) are not considered to be sexually selected nor directly influencing perceived facial attractiveness (Thornhill & Gangestad, 1994). The dermatoglyphic traits that we quantified (fingerprint ridgecounts) are similar to body traits in that they are not sexually selected, but they are canalised before the tenth week of fetal development and do not change as a result of any postnatal stress the way that facial and body traits might (Penrose & Ohara, 1973). Dermatoglyphic traits (e.g., fingertip and palm prints) have previously proven useful in the study of developmental instability in humans (e.g., Alekperov & Gashimova, 1997, Jamieson et al., 1993, Livshits & Kobyliansky, 1987 and Woolf & Gianas, 1977), but have never been studied in relation to attractiveness. In general, dermatoglyphic asymmetries show mild heritability, but are largely determined by the prenatal environment (Loesch & Martin, 1982, Martin et al., 1982, Mi & Rashad, 1977 and Singh, 1970; but see Holt, 1954 who found no heritability), and are not related to age, sex Micle & Kobyliansky, 1988 and Naugler & Ludman, 1996 or handedness (Kobyliansky & Micle, 1986). We also collected demographic and health information on our subjects to test for possible confounds (e.g., age, BMI) in any relationship between asymmetry and attractiveness. Moreover, we used this additional descriptive information to test for consistency between our measures. For example, from developmental stability theory we predicted that indicators of poor health (e.g., high BMI, Manning, 1995) and past health problems Bailit et al., 1970 and Shackelford & Larsen, 1999 would be negatively correlated with both symmetry and attractiveness. Factors such as socioeconomic status (SES), on the other hand, should be positively correlated with both symmetry and attractiveness because high SES indicates relatively low levels of stress during development (e.g., nutrition, Bailit et al., 1970). By measuring multiple traits, and factoring sex and demographic information into our analyses, we were able to examine the effect of symmetry on attractiveness more comprehensively than has been possible in previous studies. Cross-cultural studies show that attractiveness plays an important role in mate choice for males and females, although facial attractiveness seems more important to males Buss, 1989, Buss, 1994 and Feingold, 1990 and indicators of investment (e.g., status signals, social dominance, material resources) more important to females. Because males seem to be more interested in quickly appraising the reproductive value of a mate than are females (see review in Barber, 1995), they may attend primarily to physical cues indicating reproductive potential in females. For that reason, we studied the relation between attractiveness and asymmetry in males and females, separately evaluated by members of the opposite sex.
نتیجه گیری انگلیسی
Good genes theory predicts that variables contributing positively to individual health and fitness should be positively related to each other, and negatively related to variables that impact negatively on health and fitness. In this study, “positive” variables are SES and attractiveness, and “negative” variables are BMI, asymmetry and Health Problems. The results of between-variables correlations are thus generally consistent with good genes theory, although not all correlations were significant (Table 2). Our results are also consistent with the idea that female and male facial attractiveness are related to, and thus may be used as a cue to, reproductive potential Buss, 1994 and Symons, 1981. The facial attractiveness of both sexes seems to signal genetic quality in the form of developmental stability (as measured by FA), but other aspects of quality that are independent of FA may be influenced by both genes and environment in ways that are still poorly understood.