Spare Parts Read online

  We may not bare our teeth or switch a (never-existent) tail, but we, too, experience the pilomotor reflex, a.k.a. piloerection, when the very small arrector pili muscle at the bottom of each very small hair or feather follicle contracts, snapping the hair into an upright position. For animals other than us, the standing hairs or feathers or spines create a protective shield that traps warm air against the skin. This shield also protects by making the animal look larger and more fearsome when it attempts to dominate another or warn off predators wary of mixing it up with an ostensibly larger and “armored” creature. Americans call the pilomotor reaction “goose bumps” (cutis anserina). The Catalan also call it “goose skin” ( pell de gallina), as do the Czechs (husí kůže), the Danes and Norwegians ( gåsehud ), Germans (Gänsehaut), Hungarians(libabőr), Icelanders ( gæsahúð ), Latvians (zosāda), Poles ( gęsia skórka), Russians (гусиная кожа), Swedes ( gåshud ), and Ukrainians (гусяча шкіра). In France, it’s “hen skin” (chair de poule). Ditto in some parts of Italy (ciccia di gallina), in Portugal ( pele de galinha), Romania (piele de găină), and Spain (piel de gallina). It’s “chicken skin” to Afrikaners (hoendervleis), Chinese (lumps on chicken skin), Dutch (kippenvel ), Estonians (kananahk), Finns (kananliha), Koreans (daksal ), and Vietnamese (da gà). The Japanese settle for plain “bird” with torihada (bird skin).31

  Anatomists and psychologists define our stand-up hair as a visible response to physical and psychological triggers. We “bristle” when we are angry or frightened, and while our skinny upright fibers may not terrify enemies, they are definitely a signal that we are experiencing a moment of significant fear or, conversely, pleasure or sexual arousal. Perhaps you will be surprised to read that like an animal’s standing feathers or fur, your erect hairs are, indeed, protective. Your follicles sit in the dermis, which holds nerve endings connected to the root of each hair that tell it to stand in certain situations, making it an actor in a sensory warning system that alerts you to changes in your physical environment such as the movement of air or a rising or falling temperature or the almost imperceptible bonk of a mosquito’s landing. As one researcher writes, the pilomotor reflex extends your sense of touch “beyond the surface of the skin into the air and space surrounding it.”32

  Next up, or rather, down, is hair on the male chest, a secondary sex characteristic that not only wicks sweat away from the body to keep the chest dry, but also attracts the attention of some females. In 2012, Pavol Prokop and his biologist colleagues at the University of Trnava (Slovakia) published data from their interviews with 161 Turkish and 183 Slovakian women who had agreed to rate the relative attractiveness of men with hairy chests and men with smooth ones (the same men in both pictures, all photographed from the neck down). The countries have a different incidence of parasite diseases, Turkey high, Slovenia low, but in both places, the smooth chests were runaway winners, 80 percent to 20 percent. Female hormones seem to have played a role in which chest the women chose. Earlier studies suggest that during the menstrual cycle, when they are most fertile, women are likelier to prefer naked chests, while the rest of the month they are slightly more likely to like furry ones. On the other hand, Prokop hedges his bet, noting that women are individuals and cultures differ, so you expect that preferences may vary.33

  Let’s not ignore the importance of underarm hair, which also plays a role in human sexuality. Pheromones (from the Greek words pherein meaning to carry and hormon meaning to impel) are naturally occurring chemicals secreted by virtually all animals from ants to us and, some say, by plants, as well, to influence the behavior of others. Releaser pheromones draw another individual closer; primer pheromones trigger physical responses such as a faster heartbeat or a fight/flight reaction. Both men and women secrete pheromones in the liquid from the apocrine sweat glands under their arms. Hair under the arms, denser in the male armpit, effectively holds the scent in place, and, it appears, potential sexual partners appear to react based on their genes.

  The major histocompatability complex (MHC) is a group of genes that enhance our immune system’s ability to recognize and rebuff invaders. More to the point here, MHC also plays a role in creating our distinctively individual body odor and setting our preferences for someone else’s. In laboratory studies, mice seek out sexual partners whose odor differs from their own. Similar studies with humans appear to show that we do, too. In 1995, Swiss biologist Claus Wedekind assembled a group of male and female students to test female reactions to male body odors. First, he drew up the MHC profiles of each male and female volunteer. Then, he asked the men to stay “odor neutral”—no cologne, perfumed soap, smelly foods, alcohol, and tobacco—for 48 hours during which they were to sleep in the same T-shirt for two nights. On the third morning, he asked the women to sniff the T-shirts and describe the odors. Like the lab mice, Wedekind’s female volunteers were more attracted to the odors of men whose MHC differed from their own. It reminded them, they said, of current or past sexual partners. In other words, genetic opposites really do attract as, perhaps, one way in which Nature encourages pairings from different gene pools, thus promoting healthier offspring.34

  That brings us to our most sexual and therefore most useful body hair, the pubic triangle pointing down like an arrow to the male and female places where life begins.

  HAIR DOWN THERE

  Unlike the rest of the animal world, we are a species with pubic hair, a delicate area in more ways than one. Biologist Robert Anthony “Robin” Weiss, Professor of Viral Oncology at University College London, believes that that as our other body hair became less prominent, pubic hair acquired a new role as a sexual ornament, the more visible, the more attractive. To back up his case, Weiss visited zoos to peer at the groins of our closest relatives and, sure enough, he saw that on the bodies of various great apes, hair in the pubic region was much finer and shorter than elsewhere on the body, the opposite of the human pattern. This scientific voyeurism supported his argument that human pubic hair is different and probably unique, both in its evolution and in its physical appearance and purpose. Given the ebb and flow of appreciation for pubic hair vs. the naked pubis, Weiss admits that the theory is pure speculation. But until replicated, so is all science.35

  The presumptive power of red. Some adult female Old World monkeys and apes, most famously baboons, have hairless patches of skin around the genitals that swell and turn red when the females are receptive to males. More than 50 years ago, Masters and Johnson noted the prominence of red in our sexual lives. We have “red light” districts, red valentines, bright red lipstick (which cycles in and out of fashion), and no matter where you live or what culture you embrace, it seems that a woman is perceived to be more attractive when she is wearing red or sitting on a red chair, driving a red car, or just standing in a room with red walls. But does that carry over onto her body? Knowing the male fascination with red, a group of adventurous anthropologists at the University of Kent (England) wondered if the link might be to the color of the labia, which swell and darken from pink to red or even purple during sexual arousal. No one actually tried to pin that down until the Kent-ers set up a study in which heterosexual male college students were asked to rate the attractiveness of female genitals by color. No, they did not ask female volunteers to pose for the camera. They simply clicked onto an Internet site, described as “[p]roviding information about the female body … celebrating its beauty with pictures of the clitoris, vulva.” The 40 male volunteers, who had passed a screening designed to weed out voyeurs, showed no particular preference for darker shades of pink or reddish labia. In fact, they thought all varieties were equally attractive.36

  Show and (don’t) tell. In the ancient world, both male and female pubic hair might be carved or painted as triangles. During later centuries, most artists posed their baked men and women modestly covering the area, as in Botticelli’s Birth of Venus or simply erased the offending strands altogether. Michelangelo broke with this tradition when he created his David, reverting to ancient
art with stylized pubic hair; but a few years later, perhaps out of respect for the Church, none of the naked male figures he painted on the ceiling of the Sistine Chapel were similarly decorated. Female bodies in the classic European fine arts remained as smooth as Botticelli’s 15th-century Venus, rising from the waves without a single hair on her body.37 By the 1700s, female pubic hair began to make its way into pornographic art, East and West. Then came Francisco Goya’s La Maja Desnuda (The Naked Mistress), the life-size 38-by-75-inch portrait painted sometime between 1792 and 1800 and reputedly the first modern European painting to show actual female pubic hair. A second version, La Maja Vestida (The Clothed Mistress), painted at some point between 1800 and 1805, shows the same lady in the same pose, still shoeless but fully dressed. The two have been hanging next to each other in Madrid’s Museo del Prado since 1901.38, 39

  More than a half century later in 1863, Édouard Manet felt compelled to skirt the issue in his portrait of the famous demi-mondaine Olympia, placing her hand discreetly at the juncture or her naked thighs. And then, boom! Three years later, Gustave Courbet unveiled his shocking L’Origine du monde (The Origin of the World). The detailed portrait of the vaginal area is still considered too racy for Facebook, but the adventurous among you may view it right out in public at the Musée d’Orsay in Paris or in private by clicking on to the museum’s website.40

  The preeminent Victorian art critic John Ruskin (1819–1900) must have missed the first Maja. Apparently pure as the driven snow when he married Effie Gray at age 29, Ruskin is said to have fainted dead away on his wedding night at the sight of his wife’s pubic hair, leaving her to remain a virgin for the six years of their marriage. In a letter to her parents, Effie wrote that “he had imagined women were quite different to what he saw I was, and that the reason he did not make me his Wife was because he was disgusted with my person the first evening 10th April [1848].” Later, seeking an annulment, Ruskin pretty much confirmed this to his lawyer: “It may be thought strange that I could abstain from a woman who to most people was so attractive. But though her face was beautiful, her person was not formed to excite passion. On the contrary, there were certain circumstances in her person completely checked it.”41

  Mr. Ruskin was—and is—not alone. Having found that many women prefer smooth-chested men, in 2016, biologist Pavel Prokop turned the tables to ask men what they thought of female body hair. Overall, he found a preference for a naked female pubis, although more commonly in young men, age 19 to 38, than in older men. As an aside, he noted that men who identified themselves as indulging frequently in pornography were just fine with female pubic hair. Seeking an evolutionary explanation for pubic preferences, Prokop suggested that these results, which more or less correlate with the female view of chest hair, may—or may not—correlate as well with the association of parasites with hairy bodies.42 Some zoologists, such as former Oxford biologist Charles Goodhart, believe that the popularity of smooth bodies is nothing new, and that while the female preferences may be mixed, men have long preferred hairless women and chose them as mates, which is why modern women evolved to have less body hair than modern men do.43

  Parasites aside, the history of women being required to cover even the hair on their heads suggests that some men do find female hair unbearably arousing, the last bastion of female sexual secrecy and modesty. When Playboy appeared in December 1953, seven years prior to the decade of sex & drugs & rock & roll, it was okay to sell pictures of naked ladies on every corner newsstand so long as there was not a hair to be seen.44 Penthouse, which debuted in Britain and Europe in 1965 and crossed the ocean to the United States four years later, challenged that, forcing Playboy to follow with its you-could-miss-it-if-you-blinked picture in the July 1968 centerfold. The first full frontal nude Playboy centerfold was Miss January 1972. Two years later, Hustler wiped away all delicacy with virtually gynecologic views of the female sexual anatomy.45

  Today, says Indiana University’s Debby Herbenick, both men and women seem to think pubic hair is unfeminine. But, she adds, no big deal: it seems that all female body hair is unacceptable with pubic hair simply being “kind of the last to join.”46 There is a dearth of studies regarding male pubic hair, but the naked female pubis has returned with a vengeance. The Internet teems with pictures of various female hair stylings, along with passionate arguments pro and con the fashion, which, unfortunately, is not risk-free. In fact, removing pubic hair comes with an increased possibility of viral skin infections such as molluscom contagiosum (small white bumps on the skin), genital warts, bacterial cysts, scars, and ingrown hairs. Each of these unpleasant sequelae is linked to irritation and injury caused by shaving, waxing, or clipping away the hair, perhaps compounded by a less-than-hygienic salon or poor personal hygiene at home. But wait: not all the news is bad. “Laser hair removal doesn’t seem to be involved in this association,” Desruelles said, “because there are no microscopic cuts or bleeding.” And, he adds, removing pubic hair tends to lower the risk of catching or spreading lice.47

  LESS HAIR BUT NOT HAIR-LESS

  So was Darwin right? Is body hair simply a remnant? Yes and no. Our bodies do not begin at the neck and end at the navel, and even if they did, we do have as much hair there as did our ancestors, although, as noted, it is finer and less visible.

  Beyond that, we have hair where no other primate does, and what we have is clearly beneficial. To paraphrase Elizabeth Barrett Browning, let us count the ways, not of love, but utility.48

  The hair on our heads reduces the natural loss of body heat through the scalp in cold weather and, conversely, collects and holds perspiration that then evaporates, cooling the skin underneath in warm weather. It shields the scalp from the potentially carcinogenic rays of high intensity sunlight and may cushion the impact should we accidentally bang out heads against a wall. Male facial hair is not only socially significant; it, too, protects against the sun. The tiny hairs in nose and ears filter out dirt and keep out bugs. The erectable hair on arms and legs catches air waves that that tell you which way the wind is blowing and senses when a mosquito has jumped onto your arm or leg.

  But perhaps the most important function of our body hair, from top to bottom, is its role as social and sexual mediator. Where it grows and how we treat it is linked both to our social status and cultural identification. Everywhere in the world, women are more likely than men to remove various patches of hair, even sensitive ones as during the current (and perhaps temporary) trend to denude the pubic area.49 Male facial hair is linked to social status. Depending on who you are and where you are, the state of your barbering says that you are either an aristocratic or a scruffily low-class interloper. Most basically, however, our body hair commonly identifies gender, telling you in broad terms who’s a girl and who’s a boy. Capturing our pheromones, it helps to bring potential mates closer together.

  Yes, much of our body hair is hard to see, but it is fully developed and thus not rudimentary, and if you judge vestigiality by how easy it is permanently to remove a body part, this doesn’t make the cut. It would be impossible to remove the millions of follicles that produce our hair.

  They are ours.

  They are there.

  And they are not going away anytime soon.

  3

  The Tale of the Tailbone

  The Coccyx

  “In times of joy, all of us wished

  we possessed a tail we could wag.”

  —W. H. Auden

  “In man, the os coccyx, together with certain other vertebrae hereafter to be described, though functionless as a tail, plainly represent this part in other vertebrate animals. At an early embryonic period it is free, and projects beyond the lower extremities; as may be seen in the drawing of a human embryo. Even after birth it has been known, in certain rare and anomalous cases, to form a small external rudiment of a tail. The os coccyx is short, usually including only four vertebrae, all anchylosed together: and these are in a rudimentary condition, for they consist, with the exce
ption of the basal one, of the centrum alone. They are furnished with some small muscles; one of which, as I am informed by Prof. Turner, has been expressly described by Theile as a rudimentary repetition of the extensor of the tail, a muscle which is so largely developed in many mammals. The spinal cord in man extends only as far downwards as the last dorsal or first lumbar vertebra; but a thread-like structure (the filum terminale) runs down the axis of the sacral part of the spinal canal, and even along the back of the coccygeal bones. The upper part of this filament, as [William Turner, professor of anatomy at the University of Edinburgh] informs me, is undoubtedly homologous with the spinal cord; but the lower part apparently consists merely of the pia mater, or vascular investing membrane. Even in this case the os coccyx may be said to possess a vestige of so important a structure as the spinal cord, though no longer enclosed within a bony canal.”

  —Charles Darwin, The Descent of Man

  THE INCREDIBLE VERSATILE TAIL

  A tail is a many-splendored thing. T Rex’s massive appendage was a counterbalance that kept his very big body from tipping over to land him on his head. A hippopotamus swirls his tail in a circle to swish feces about, thus marking his territory. A fish’s tail whips from side to side to propel him through the water. Like birds, cats use the tail as a rudder, the former while flying, the latter while leaping, possibly after the former. An alligator’s tail is a fat depository that stores energy for future use; so is a quokka’s.1 A monkey’s tail is a prehensile appendage that can grasp and hold an object such as a branch, enhancing the ability to swing through the forest.2 Cows and horses use theirs to brush away annoying insects, which is a good thing, although in Animal Farm, George Orwell imagined Benjamin the Donkey saying that “God had given him a tail to keep the flies off, but that he would sooner have had no tail and no flies.”3 Finally, a scorpion’s tail or a bee’s is an attack weapon used to inject venom. Rattlesnakes, on the other hand, are more considerate; they use the noisy tail to warn potential victims of an impending attack—which comes from fangs, not tail.