A few years ago, I was hunting sheep alone on a steep hogback ridge in the Wrangell Mountains. The crest was only a sheep trail wide. To the west the ridge broke away into precipitous rimrocks, unmanageable without serious mountaineering gear, but to the east the steep talus swept downward into a smoothly carpeted basin. I could see 27 mountain sheep in all that basin, and there were some middle-aged and young rams not far below, oblivious to my presence. They were too exposed for a stalk so I waited. Some rams were feeding quietly and others were bedded down facing the valley floor. There was some social bantering and displacement from bedding sites as the afternoon wore on.
Then I saw the strangest sight. Two animals were copulating. Impossible - rutting season was four months away. I swung the spotting scope over on the two animals; the ewe was bending her back to allow the ram to penetrate. Then something definitely looked wrong, for a moment I didn't see it - but there it was. The ewe wasn’t a ewe after all, but a young ram - both were rams.
It wasn't until a year later, after Valerius Geist's work on mountain sheep behavior had been published, that what I had seen that day took on meaning. The young subordinate ram was assuming the female's copulatory posture as a ritualized display of subordination; and by mounting him, the dominant ram relegated him to the status of a mere ewe. Here was status sex in its most diagrammatic form.
Male sexual organs signal dominance. The evolution of sexual signals coming from the female are quite different. They have a large component of attraction, though man's subordination gestures and social organs of submission arise from female reproductive parts.
Throughout most vertebrates there is a general rule that the female has the copulatory lures well developed and the male the threat organs well developed. There are some exceptions to this; for example in some species the sexual roles are switched due to some mechanical quirk of polyandry or nest tending. Human beings, however, go along with the basic rule. Kathrin Perutz, in her analysis of beauty, stated it better than any anthropologist:
"Love traditionally follows a beautiful woman as it does a powerful or successful man... Men's fashions are used to announce his affluence and taste, not to attract sexual partners. Femininity is associated with curls and lashes, blushing cheeks, alabaster brows, and ruby lips, but masculinity is shown by action."
There is a beautiful story behind how females came by their copulatory attractants and what they are. We know them well, they are part of our daily aesthetics, but that's just it: they are so close to us that it is difficult to stand back and look at them objectively. Using principles from other organisms we can get some insight into our own emotions and values - how we are similar and different.
A sweep across the primates reveals two basic themes relating to sexual attractants. The first and most obvious concerns the primary genitalia and the area around them. The second is not so apparent: it relates to our mode of development of sexual behavior, the majority of which in primates stems from nursing. Let me take these up in detail, one at a time, though they are in fact related.
First, the female's vulva region is the "hot spot" of attraction in most mammals. It is often contrastingly colored or enlarged in heat and is a major odor-producing area. In addition to producing local odor, the glands also scent the urine. What an annoyance to have a pet cat in heat: she wants to dribble her urine all over the neighborhood, and if she can't get outside, then she does it all over the house. Many, if not most, ungulates and carnivores scent their urine in heat so that not only does the vulva region smell, but everywhere she has been recently tells the story "Here I am; come on if you want me." Judging from the behavior of males, the sight is attractive and so is the aroma.
I think the female's vulva, as the visual target area for copulatory attraction, has been responsible for the evolution of rump patches. The vulva colors or the colors around the vulva expand across the whole butt, carrying a stronger signal that "there" is the sexual end. Females of many species have a rump display which mainly functions as a sexual presentation. Among many species it has taken on a secondary meaning of submission, because it is used to remotivate an aggressor into a sexual mood.
The gesture of rump presentation can easily be modified into a submissive gesture, which transcends the original sexual differences. Males can then "present" their rears to other males in appeasement and females can "present" to other females. There is an entire gradient representing this evolutionary series among different mammals. The whole behavioral spectrum of rump patch evolution can best be seen in the primates. We now have more information about the behavior of this group than any other mammalian order. In some lemurs rump presentation is only made by females during their estrous peak. However, in the chimp, rump presentation is made by the female to males at any time, not necessarily when she is fertile, apparently as a signal of submission. The common langur uses the rump presentation as a submission signal in both sexes. Females commonly present to other females as well as to males. A further step in the evolution of this gesture is made in some groups by their using the rump presentation as a greeting or reassurance gesture, such as in the hamadryas baboon. Many greeting gestures arise out of submission signals, whereby both individuals show there is no hostility toward the other.
Among mammals with poor color vision, rump patches are light or cream colored. Apparently this color is an expansion outward onto the flanks of the white underbelly color that normally comes up near the ano-genital area. Among primates, however, who have excellent color vision, the rump patch is often naked (except in some lemurs, where it is white), and usually a brilliant vermilion, purple, blue, or lilac. These rear swellings grow larger than usual in zoos and are familiar to every zoo-goer. They also enlarge in size when the female is in heat - a flashy visual advertisement of her state. It is interesting that our nearest living anthropoid relative, the chimp, has the best developed rump patch of almost any of the primate groups, and we do not - though we certainly must have had some gadget back there in the past.
We do, however, focus on that area as a center for sexual attraction. Reference to the buttocks is equivalent to copulation in our slang. And it is not surprising that special organs have evolved to complement that signal. The swollen buttocks of the European paleolithic carvings and the presence of steatopygia (excessive development of fat on the buttocks) among the Bushmen, Hottentots and South Andamanese suggest that greatly enlarged rears may have been the original human condition. In general we have shifted to a teardrop ideal, away from gigantic bulges toward a more sideways "broad" outline. The thread of this ancestry keeps returning in such forms as bustles.
A female Bushman illustrating a posterior protrusion of the buttocks (steatopygia). The bustle of and earlier era in Western cultures seems to have served a similar function (after Wickler, 1967).
Rump patches of most animals are expansions of the female sexual signal out onto the rear. In some mountain sheep the rump patches fan out to cover the entire rump and pass down the posterior part of the legs. The human zone of sexual attraction also spreads out from the genitals to the buttocks to make the buttocks a sexy thing. Like the mountain sheep, it passes down the posterior part of the legs to include thighs, calves, and ankles. The white portion in the illustration of the human female’s legs sets off the main erotic zone. The lines of the buttocks, thigh, calf and ankle have a native sexual stimulation, but this can be increased with the high-heeled shoes; the curves are exaggerated when the heel is lifted. These curves are particularly apparent in a ballerina’s toe stance.
Buttocks still play the major role in sexual attraction - even though the usual copulatory approach is forward, face to face. The groin area is erotic, but still not as much as the rear. The rear is the last thing to be disrobed in modesty; if it were just the vulva which had to be hidden it could be easily done, but someone with a bare bottom is considered nude. Rationally it appears peculiar - why should a structure that we sit on become an erotic zone to pinch and fondle? But the primate pattern tells the story: it is the copulatory zone, where one approaches if he is male and what presents if she is female.
Rump patches in other organisms aren't limited to buttocks, however, but flow down the back of the leg like dripping cream to reach the heel. This is especially true of the sheep. From the rear view the whole poster is a sexual signal. So it is also with humans. The buttock region is the focus of sexual attraction, but the erotic zone flows down the back portion of the leg from the thighs' backside, the knees' backside, over the smooth lines of the calf, to the ankle.
Such a standard is scarcely ideal, of course, because it has no rational bearing on copulatory readiness, expertise, or anything else; we are just following the pattern of our ancestors, both the last generation and ten thousand generations ago. What a crazy animal we are! A woman with a pancake bottom just doesn't come across - like the man with a receding chin, she doesn't have the social paraphernalia we require; yet she may be ideal in every other respect.
The other area of sexual attraction is tied up with nursing. It is concerned with a transference of the maternal-child attraction to a sexual attraction between adults. Our attraction to members of the opposite sex has to come from someplace, and our sense of oral and genital satisfactions begins to be built in the early child-parent relationship. Though not a directly comparative work, one of the most stimulating discussions to be published on this subject recently was Terence Anthoney's work on the yellow baboon.
The baboon infant's main activity in its first few weeks is nursing, that is, sucking. A closely related gesture (and apparently a derived one) is lip smacking, which is a sucking smack in the absence of a nipple. Older infants sometimes do this toward nipples they are not allowed to nurse. When the young are small, nearby females lip-smack in their faces while grooming the mother, just to enable them to be close to the newborn. The mother also lip-smacks the genital area of the young. After she lip-smacks the penis for several seconds it immediately becomes erect. As the infant grows older it embraces rather than trying to nurse. If the female is in estrous she frequently presents her rump to him and lip-smacks over her shoulder. The infant mounts (an infant's grasping reflex), thrusts, and sometimes achieves intromission.
Lip-smacking is also associated with greeting. Oral grooming seems to have developed as a means for juveniles to remain near the females and gain some of the nursing security without being driven off when attempting to nurse. Instead, they lip-smack the hair. Later in life the lip-smack is used toward peers to show amity and to allow them to be near one another. All of these gestures (nursing, lip-smacking, erection, mounting, grooming, and greeting) become interconnected as part of the socio-sexual development of the young.
Why should we associate breasts - the mammary glands used to feed young children - with adult sex? There is no rational association unless one begins to understand the developmental aspects of general sexual stimulation. Nursing and the gestures derived from it contribute to the development of adult values and behavior, among them sexual stimulation.
Nursing and the gestures derived from it contribute to the development of adult values and behavior, among them sexual stimulation. We have some sort of a breast fixation. It is our first experience with lost security (a rubber nipple substitute in the breast vicinity seems to have the same effect). Like yellow baboons, boy babies get erections while nursing. Why have the erotic acts of cunnilingus and fellatio developed? Kissing and nuzzling are curious erotic gestures, yet they are all takeoffs on nipples and nursing.
Pink nipples, pink tongues, and pink penises all thrive on a common signal. Why is French or soul kissing regarded as an upper-story form of copulation, known to bring orgasm from either party? And why do men and women alike consider nipple-sucking an erotic form of precopulatory play? Because it's actually quasicopulatory. It's where they were first stimulated sexually. The Oedipus urges have a biological undertone. Through our parents we prepare ourselves for life competitively and sexually. In the prepuberty years, long before we learned of the strange goings-on after puberty, our nervous system was gearing up our values of physical love, about using genitals and lip-smacking our bed partners in years to come.
Though the origins may be dual, we cannot talk about just two separate entities, then, the breasts and buttocks, but the whole developmental syndromes that involve many parts of the body - noses, lips, tongues, nipples, penises, and so on. Nose to nose, nipple to nipple, tongue to tongue, and genital to genital, the wiring is all interconnected as two sexes stand together. Themes of lilac-pinkness, stem-like projections, and sucking begin to assume broader behavioral significance outside their original functions.
Interestingly enough, the wiring is such that it can easily get crosswired into homosexual activity, because the development of sexual reward is much the same in both sexes. It is the status - the hierarchy - component which plies the sexes into their sexual compartments, and it is here where the wiring of heterosexuality can easily be shorted.
We aren't baboons and don't go around sucking baby genitals, you'll say. But almost all the script is there and we do very similar things. By we, I mean the Western world. Some tribes in New Guinea have a tradition of the female lip-smacking the penis of the male baby. It is not foreign to human nature to make direct associations between infantile nursing and copulation.
We do some strange things in the heat of sex, or even better yet in the fantasies of early puberty, and if you stop to analyze them for their own inherent worth, they are as idiotic as elbow banging or heel rubbing for kicks. But immersed in the milieu of our primate background, our modes of love-making take on a special meaning.
Females have different selection pressures on their physiques than males, for a multitude of reasons. One of these is that a woman must carry a baby in her womb and be able to pass it through a portal in her pelvic girdle. So among most mammals the female's pelvis is quite differently constructed than the male’s.
Among human beings, the wider birth opening in the female's pelvis necessitates a slightly wider pelvis than the male’s. The erogenous character of this pelvic region is also reinforced by the proximity of the erogenous buttocks. The hips are much wider than they "need" to be. Many svelte hipped women give birth with no more difficulty than some with wide hips.
Actually, hip width is not so simple a thing as it appears. It relates to both the width across to the upper bony flange (the ilium), the head of the upper thigh bone (the femur), and the fatty deposits which cover them. Women vary considerably in these measurements, and they are often disproportionate. For example, a woman with a narrow ilium width and wide femur span has a teardrop droop to her hips. One with a narrow femur span and wide ilia has an inverted triangle form with "shelf" hips. Both of these areas expand rapidly at puberty, making a gangly teenager into a true "broad." The buttocks undergo some swelling at puberty, complementing the expansion of the entire bottom area.
The breasts also blossom at puberty, along with the chest and shoulder width. However, women do not experience the dramatic shoulder and chest broadening seen in general among males at puberty.
The female waist, strikingly enough, undergoes no perceptible change in dimension at puberty. Actually, from the age of about six or seven the waist seems to stabilize. The major fat depots are away from the waist in most women, so that even though she is gaining weight, a woman's waist changes less than other areas like the thighs. Men, however, have a major fat depot in the "spare tire" area, and the waist is one of the first areas to change when fat is added.