Sunday, November 18, 2018

Looking through a lens



The Babylonian goddess Ishtar (Louvre). The cult of feminine whiteness reached its height in a zone stretching from the Mediterranean through the Middle East and into South and East Asia



Skin color differentiates between the sexes at puberty, with complexions becoming paler in girls and ruddier and browner in boys. The cause seems to be hormonal. This is most convincingly shown by recent studies on digit ratio in men and women before and after puberty and by earlier studies on normal, castrated, and ovariectomized subjects (Edwards and Duntley 1939; Edwards and Duntley 1949; Edwards et al. 1941; Manning et al. 2004; Sitek et al. 2018).

How noticeable is this sex difference? If we take the best controlled studies, where this sexual differentiation is measured at the upper inner arm, we find that boys and girls differ after puberty by about one and a half percentage points of skin reflectance (Kalla 1983; Mesa 1983). By comparison, northern Europeans and West Africans differ by 25 to 30 percentage points (Robins 1991, Tables 7.1, 7.2).

Keep in mind that these measurements are from the upper inner arm and that measurements from other body sites show a much larger sex difference. On the buttocks and the breasts, skin reflectance differs by 6 to 15 percentage points between men and women (Edwards et al. 1939; Garn et al. 1956). The literature has always ascribed this finding to differences in dress and, hence, to differences in sun exposure, yet female skin is lighter at these sites not only because it has less melanin but also because it has less blood in its outer layers, a fact hard to reconcile with a simple tanning effect. 

There is reason to believe that women are lighter-skinned where their subcutaneous fat layer is thicker, possibly because body fat contains an enzyme (aromatase) that converts an androgen (androstenedione) into an estrogen (estrone), thus feminizing the skin (Siiteri and MacDonald 1973). Indeed, lightness of skin color correlates with thickness of subcutaneous fat in adult women (Mazess 1967).


Visual processing of this sex difference in the human mind

Whatever its actual magnitude, we seem innately predisposed to notice this small difference in skin color, particularly for face recognition. Research is ongoing, but there is a growing consensus that "color is not merely an accessory of faces, but is rather a complex and crucial feature in facial processing. [...] Further, recent work has revealed consistent patterns of connected face and color selective cortical areas, possibly reflecting a shared overlap of visual processing between faces and color" (Thorstenson 2018).

Faces are recognized by means of many neurons, some of which specialize in recognizing male faces, others in recognizing female faces, and others in recognizing both indifferently (Baudouin and Brochard 2011; Bestelmeyer et al. 2008; Jacquet and Rhodes 2008; Little et al. 2005). To recognize gender, one of the key visual criteria is skin color (Bruce and Langton 1994; Hill, Bruce, and Akamatsu 1995; Russell and Sinha 2007; Russell et al. 2006; Tarr et al. 2001; Tarr, Rossion, and Doerschner 2002). In particular, these neurons use two aspects of facial color: hue (degree of brownness and ruddiness) and luminosity (degree of contrast between lightness of facial skin versus darkness of lip/eye area). Hue is the fast channel for gender identification. If the face is too far away or the lighting too dim, this mental mechanism will switch to the slower but more accurate channel of luminosity (Dupuis-Roy et al. 2009; Nestor and Tarr 2008a; Nestor and Tarr 2008b; Tarr et al. 2001; Tarr, Rossion, and Doerschner 2002). 

It has been shown that an observer can identify the gender of a face even if the image is blurred and differs only in color (Tarr et al. 2001). Indeed, facial color seems especially crucial if face shape is not clearly visible (Yip and Sinha 2002).

Even when not observing a human face we unconsciously associate darkness with men and lightness with women. This was shown in a series of experiments with Dutch, Portuguese, and Turkish participants. In the first one, personal names were gender-recognized faster when male names were presented in black and female names in white than when the combinations were reversed. In the second experiment, very briefly appearing black and white blobs had to be classified by gender; the former were classified predominantly as male and the latter as female. Finally, in an eye-tracking experiment, observation was longer and fixation more frequent when a black or dark object was associated with a male character and a white or light object with a female character (Semin et al. 2018). Similar results come from a word-association test with Navajo participants: the color black was perceived as more potent and masculine and the color white as more active and feminine (Osgood 1960, p. 165).

We therefore perceive skin color, and especially facial color, through the lens of a mental mechanism that initially arose for gender recognition. This may explain not only why lighter skin is subconsciously perceived as feminine but also why women have sought to accentuate this relative pallor in a wide range of cultures and time periods, most often by avoiding the sun and wearing protective clothing (Frost 2010, pp. 120-123). To the same end, and often independently in different geographic regions, powders have been created from white clay, lime, chalk, or gypsum for the purpose of lightening women’s facial color or increasing its contrast with lip/eye color (Russell 2003; Russell 2009; Russell 2010).

This cult of feminine whiteness reached its height in a zone stretching from the Mediterranean through the Middle East and into South and East Asia. Here, the sex difference in skin color could develop to its fullest, without being constrained by the ceiling of very light pigmentation or the floor of very dark pigmentation. Here too were invented the first cosmetics for women, including powders to lighten skin artificially, and accessories to keep skin untanned (parasols, long gloves, conical or wide-brimmed hats). Finally, here too were created the first works of prose, poetry, and visual art, often on the theme of female beauty, including feminine whiteness. The collective imagination thus became populated with women much fairer than their real-life counterparts.


The advent of the tanned look and the end of feminine whiteness

This cult of feminine whiteness came to an end in the Western world when women embraced the tanned look in the early 20th century. This look began as a side effect of heliotherapy, i.e., the use of sun baths and sun lamps to treat rickets, tuberculosis of the skin, and other cutaneous diseases. By 1929 it had become a fashion, to the surprise of observers like this New York Times journalist: "Idealists would like to believe that the people, investigating the medical doctrine and accepting it as sober fact, went deliberately forth to get what was good for them, and took to sun baths with an avidity they had never shown for spinach, sleep, or orthopedic shoes" (Segrave 2005, p. 35). The new fad had become especially popular with women and, as such, entered into the boyish look of the 1920s: bobbed hair, large shoulders, small bust, narrow hips, and long legs. The intent was to evoke the image of a boy on the brink of puberty, as shown by the French name of this fashion trend: la garçonne.

While the first nudist movements were organizing, la garçonne freely exhibited her athletic body and enjoyed the benefits of heliotherapy. The 1920s made tanning fashionable. Translucent skin and pale complexions were relegated to the theatre prop room of fin de siècle romanticism. Thus disappeared an element of gender differentiation. The contrast of flesh colors, brown and copper for the man, white, pink, and ivory for the woman, had been a constant since Ancient Egypt in literary and pictorial representations. (Bard 1998, p. 41)

The tanned look tapped into an erotic response that had previously been marginalized and stigmatized. In Victorian era novels, the "dark lady" appears as an "impetuous," "ardent," and "passionate" object of short-lived romances (Carpenter 1936, p. 254). Similarly, in French novels of the same era "[t]he love incarnated by brown women appears as the conceptual equivalent of a devouring femininity, thus making them similar to the mythical figure of Lilith" (Atzenhoffer 2011, p. 6). This motif goes back at least to the Middle Ages in various European cultures and points to an alternate mode of eroticism:

[...] dark girls [...] are inevitably imagined as sexually more available than their fairer sisters, with whom they are implicitly or explicitly contrasted. In addition, the change of a girl's complexion, such as being burned by the sun, is to be understood as symbolic of her having crossed a sexual threshold without the benefit of marriage. (Vasvari 1999)

European folklore has sayings along the lines of "the darker the berry, the sweeter the juice," such as the following from a Venetian folk-poem:

"My lady mother always told me that I should never be enamoured of white roses," says a sententious young man; "she told me that I should love the little mulberries, which are sweeter than honey." "Cara mora," mora, or mulberry, meaning brunette, is an ordinary caressing term. (Martinengo-Cesaresco 1886, p. 95)

This is consistent with the idea that women evolved lighter skin not as a means to stimulate male sexual arousal but rather as a means to modify such arousal by reducing aggressiveness in the male observer and inducing feelings of care. Women are thus lighter-skinned for the same reason that they have less body hair, a higher pitch of voice, and a more babyish face. These are all key aspects of Konrad Lorenz's Kindchenschema (Lorenz 1971, pp. 154-164). Another ethologist, Richard Russell, was the first to use this concept to explain women's lighter skin:

I believe the sexual differences in skin color resulted from female whiteness being selected for because it is opposite the threat coloration, although the selection pressures may have been rather mild. Light skin seems to be more paedomorphic, since individuals of all races tend to darken with age. Even in the gorilla, the most heavily pigmented of the hominoids, the young are born with very little pigment. [...] Thus, a lighter colored individual may present a less threatening, more juvenile image. (Guthrie 1970)

This explanation is supported by a two-part study where each male participant was first shown pictures of women and asked to rate their attractiveness. Women with lighter skin were not rated more attractive than those with darker skin. In the second part, eye movements were tracked, and it was found that women with lighter skin were viewed for a longer time. The longer duration could indicate a slower rise and fall in sexual arousal (Garza et al. 2016). Women's lighter skin may thus lengthen and pacify male sexual arousal via a Kindchenschema effect.


Conclusion

Today, skin color is seen as a mark of ethnic identity, yet this is not the sole meaning it has had for humans. For most of history and prehistory it was seen as a mark of male or female identity.

This older meaning has received much less interest, even in academia. It is perhaps no coincidence that scholarly interest has come disproportionately from non-Westerners. In contrast, Western academics, and Americans in particular, generally view the psychological meaning of skin color as a legacy of slavery.


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1 comment:

Sean said...

There were white people in the north during the Mesolithic, but also very dark people in continental Europe in the Mesolithic and even into the Neolithic. Ice age and Bronze age white
skin had the necessary hack to disable man's inclination for as many low commitment relationships with women as possible, but I think the thing lacking in the Mesolithic to make white skin in and of itself an absolute advantage was the death of a lot of men.