5

The Brain of Sex

I speak two languages-Body and English.

—Mae West

Sex escalated evolution greatly by creating greater chances for change, but it didn’t have to be that way. When one tries to imagine a world without sex, it doesn’t seem possible. Of all the things we spend our time consumed with, sex is numero Uno. Trickster stories reveal those parts of the brain that still throb below the neocortex, those parts that motivate our sexual desires. But the all-consuming power of lust the trickster stories bear witness to occur alongside the rules and customs of society, alongside culture and its memes. Even such a libertine character as Trickster must operate in a world of constraint. Without restraint, trickster stories could not have emerged. For human cultures everywhere mandate various prescriptions for sexual activity (guaranteeing that an opposing force against restriction would emerge). Even in Puritanical America, one of the most religious countries on earth, every aspect of our media is saturated with sexual imagery—films, TV, magazines, commercials, visual art of every variety, as well as literature: novels, poems, and songs. (Indeed, many have argued that Las Vegas could only have emerged in a Puritan country, for repression is the engine for acting out.)

The time and energy devoted to sex for all species is immense. Though we know that the many complications of sex do not make our world any easier, sex certainly makes for an infinitely more interesting place to live in than if we were asexual. Yet, the surprising fact to most people is this: to perpetuate life on earth sex wasn’t necessary. As a matter of fact, one of the biggest biological puzzles has been why there is sex at all. Many species propagate perfectly well without it, and being asexual saves a world of energy and stress. From an evolutionary perspective, if it is the selfish genes (as Richard Dawkins brought to light) who are motivating the life force, why would any creature want to split his or her selfish genes with someone else’s—in effect halving them? Why not just reproduce in toto? Why not clone? Asexual reproduction is terribly more efficient than sex, and many animals have this ability: bacteria, amoebas, jellyfishes, echinoderms (of which starfish are a variety), corals, tapeworms, as well as some insects, fish, lizards, and frogs. The largest lizard on earth, as a matter of fact, the female Komodo Dragon, can reproduce on her own if no male is in the vicinity. And there are numerous plants that can recreate themselves without sex: they send out runners, or stems, which then form roots of their own. Willow trees do it—dandelions, grasses, sedges, and cattails. Even potatoes do it. In addition many species can reproduce themselves both asexually and sexually, like the Komodo Dragon and like the aphids, who will madly reproduce asexually all summer long, then suddenly have one big bout of sex before the onslaught of winter. Why? If species can successfully clone themselves, wouldn’t cloning be the best and most efficient strategy? Well, it turns out that sex does much more than cloning does to make us fit.

Sex, Disease, and Competition

In The Red Queen, Matt Ridley deals with the technicalities of sex and genes that most of us have either forgotten from high school biology, or never learned:

Genes are biochemical recipes written in a four-letter alphabet called DNA, recipes for how to make and run a body. A normal human being has two copies of each of 75,000 genes in every cell in his or her body. The total complement of 150,000 human genes is called the “genome,” and the genes live on twenty-three pairs of ribbon-like objects called “chromosomes.” When a man impregnates a woman, each one of his sperm contains one copy of each gene, 75,000 in all, on twenty-three chromosomes. These are added to the 75,000 single genes on twenty-three chromosomes in the woman’s egg to make a complete human embryo with 75,000 pairs of genes and twenty-three pairs of chromosomes.

A few more technical terms are essential, and then we can discard the whole jargon-ridden dictionary of genetics. The first word is “meiosis,” which is simply the procedure by which the male selects the genes that will go into a sperm or the female selects the genes that will go into an egg. The man may choose either the 75,000 genes he inherited from his father or the seventy-five thousand he inherited from his mother or, more likely, a mixture. During meiosis something peculiar happens. Each of the twenty-three pairs of chromosomes is laid alongside its opposite number. Chunks of one set are swapped with chunks of the other in a procedure called “recombination.” One whole set is then passed on to the offspring to be married with a set from the other parent—a procedure known as “outcrossing.”

Sex is recombination plus outcrossing; this mixing of genes is its principal feature. The consequence is that the baby gets a thorough mixture of its four grandparents’ genes (because of recombination) and two of its parents’ genes (because of outcrossing) . . .

Put this way, sex immediately becomes detached from reproduction. A creature could borrow another’s genes at any stage in its life. Indeed, that is exactly what bacteria do. They simply hook up with each other like refueling bombers, pass a few genes through the pipe, and go their separate ways. Reproductions they do later, by splitting in half.

So sex equals genetic mixing. The disagreement comes when you try to understand why genetic mixing is a good idea.1

The reason for sex has everything to do with parasites, viruses, germs, and bacteria. Outcrossing is about keeping an individual safe. In evolution, there is always a war going on for survival between animals and those that live upon them. As Ridley states bluntly, “Sex is about disease.” Sex allows for new combinations of defense strategies (antibodies) to be constructed through different combinations of DNA. So as viruses and bacteria constantly evolve to invade us, our immune systems are constantly trying to outwit them. Because of disease, asexual species can quickly be wiped out by a single strain of an enemy invader. For they have one strategy, and if it fails, that’s the end of their genes. This is why even species that are mostly asexual occasionally indulge in sex. It’s an insurance policy. In the same way, sex also creates resistance to the accumulation of bad genes (that accrue through random mutation). Through sex, you are creating not a clone, but an offspring who might have a better chance of fighting off the invaders or the genes that will make you weak. Sex gives an individual a whole new complex of genetic tricks. And it turns out we keep these old genes for making antibodies around for generations and generations, in the event an enemy will pull out a genetic trick of their own from the ancient past and try to invade us with it once again; consequently, we even share (and retain) some of our disease-fighting genes with cows, from way back when we and cows had a common ancestor!2

Displays

During mating season, everything from fish to birds to lizards to mammals of every color and stripe become consumed with nothing but sex: they don’t eat or sleep, and some don’t even make it out alive. It is common for successful bull elk to not live through the winter after a vigorous rut, the strain of mating and rounding up a harem of cows depleting every ounce of the bull’s strength (but still: his genes survive). For females too, the courtship rituals are often intense and consuming. For females the act of laying eggs or going through pregnancy presents great difficulties, which can rob them of energy or cost them their lives.

But the one biological fact that determines the differences in how males and females behave comes from the great disparity in the distribution of sexual cells. In humans, for example, the female has one egg at a time that may be fertilized, while a man produces 250 to 500 million sperm for every ejaculate. This is the reason that, throughout most of the animal world, the female must be pursued. She has more at stake in the mating process and has to be extremely picky. In the animal world it is the female who chooses her partner. She has only one vehicle for passing on her genes: her single or handful of eggs. Nature has programmed females to desire the best genes for their offspring, which means they are attracted to the most successful males, those who portray dominance and virility.

In many bird species monogamous behavior occurs because of the necessity of both males and females hatching the eggs and raising chicks. In order to incubate, one parent must sit on the eggs at all times while the other goes off and procures food. If the female picks a mate who is a deadbeat, who is negligent in his duties, her chicks won’t survive. But the loyal mate may not always be the sexiest one on the block. Males and females have different sexual strategies because of their reproductive anatomy. Theoretically, a male can impregnate an endless number of females. In the case of the most handsome male birds (whose bright colors equal fitness)—they will be highly sought after by females—but it is in the interest of these pretty-boy males to inseminate as many of these star-struck females as possible (for they will have more offspring)—letting some other drabber looking male falsely believe that he is the father. Surprisingly, DNA studies have confirmed that even in bird species thought previously to be monogamous, nearly 40 percent of females cheat. She can have her cake and eat it too if she sneaks off with the flashy male, and doesn’t get caught by her boring “husband.” But if the drabber husband discovers that he’s been cuckolded, he’s out, and the female will have no one to help her sit on the eggs or raise her chicks when they hatch. The good-looking player who really mated with her is already far down the road, no doubt having a dalliance with another gal bird looking for some flash. (It turns out that in birds, the best-looking males are often not loyal.) An entire mating season will have occurred without propagation of a single life. It’s all a very risky game in which the stakes are enormously high. Sex goes far beyond men are from Mars and women are from Venus. It’s a Herculean life and death struggle, and the entire survival of the species depends upon sexual success.

What leads to the physical differences between males and females is polygyny—a male with multiple female breeding partners, (though Darwin showed that even in monogamous relationships change can occur between males and females, more slowly, through the fact that the offspring of “fitter” parents will be much more likely to survive and pass on their genes). The flashier males have more offspring because the females desire them, and the males have more sexual partners and more chicks. The next generation of males tends to have more outlandish feathers because of this. Females also get the genes for desiring these kinds of flashy feathers over the ones without pizzazz. The process of excessive traits developing, like the iridescent feathers of many male birds, is called the Runaway Theory, developed in the 1930s by R. A. Fisher. Through transference, to both males and females, the next generation will have flashier feathers. Males want sex and will get it wherever they can, so there’s no pressure on them to be picky. Even if they have a special mate, it doesn’t matter. If they can get a little action on the side, they’ll go for it, as it only adds to their genetic legacy. The thing is, the male doesn’t care one whit if a female looks flashy or drab. For him, a female’s a female. But the picky females will only go after the flash (for the flash indicates fitness), so once these preferences and mating practices come into play over generations we get what we see in nature: males with fantastic plumage and females who often look dull by comparison. But males and females can lie. From the genes’ perspective, the point is to reproduce. What looks good on the male doesn’t have to really be good so long as it attracts a mate. The female needs to make reliable decisions based on truth, not deception. The health of her eggs depends upon it. So the male must show that he’s the real deal and be able to beat off the pretenders through some method. Darwin, before coming up with the solution of sexual selection to explain exaggerated forms in nature, was very worried that extreme markers would contradict everything about natural selection. A woolly mammoth with tusks too big to carry around would not be good for much. The peacock’s tail drove Darwin insane. But he finally figured it out. Sexual selection is the process by which (primarily) females choose males, and this choosing has led to nearly all the marvels of color and design we see in the animal kingdom, from feathers and scales to the cuttlefish’s electronic skin.

In 1997 A. Zahavi brought out the Handicap Principal, which further explained why extremism could still benefit a species. When a male takes on the burden of extra baggage it represents additional strength and vitality to carry the extra “weight.” In other words, males in some species evolved ridiculous burdens to prove they were not faking it. To carry huge tails, antlers, or tusks is not an easy thing to do; as a matter of fact it’s often quite dangerous. A Bird of Paradise can’t easily fly from a jaguar; a bull elk can get his antlers tangled in a tree or hooked up with another male and die. These things happen in nature. But even though these sexually selected traits might seem “foolhardy” to us, what they prove to the females is that this guy must be really macho to be able to handle all that extra baggage. He is super-fit.

When extremism is found in nature, from the throbbing hues of tropical fish, to the massive antlers of moose, it’s a sign that sexual selection has been at work. Handicap traits might show that an animal is extra healthy, free of parasites and disease. Of course, there will always be physical constraints against how far the Handicap Principal can go, which probably explains why many species, such as the Irish elk, went extinct. If antlers get too big for the males to carry successfully, the males (and species) will die. Extinction has happened tens of thousand of times in the past as a matter of fact most animals that ever lived have gone extinct. But regardless of the danger of the Handicap Principal, sexual selection has given us the great raft of diversity we see today—the fantastic radiation of life in its myriad forms—and possibly the very best things about our own species.

It seems strange to us that in most other species it is the male who is adorned with the brightest feathers or most extreme projections, such as antlers, while in humans it seems to be the females of our species who have more “eye candy.” But we humans have also developed culture, and in most primal cultures the fashion and rank displays, such as feathered headdresses, piercings, body paint, tattoos, and other adornments are utilized by men as status symbols of wealth and power. In the modern world, status symbols, such as Porsches and Mercedes Benzes, also tend to be most often associated with male displays of hierarchy. But the human animal is also quite different in two ways from other primates—1). In our species, both males and females are involved in intense competition for mates. In birds, the male is always ready for a dalliance. But in humans, the survival of one’s DNA depends on a much more concentrated and lengthy process of cooperation, as a human child takes well over a decade to raise. Those children that had both a mother and a father around to provide resources and parenting (as well as a grandma) had a greater chance of survival than those who had a mother alone. As a consequence of this sexual competition, both males and females have an intense interest in displays for fitness (still, more for males); consequently, females also show specialized physical attractors, such as pronounced breasts and more juvenile faces. Because so much is at stake in terms of a child living to adulthood, females will fight vigorously for their mate in order not to lose out on valuable resources the husband can provide. These emotions are manifested as love and attachment. Jealousy evolved as a radar system to detect signs of cheating and to fuel rage at threatening behavior from a spouse. The male can also become extremely jealous and protective of his mate. The “double standard” arises from the fact that the male still desires to spread his genes throughout the population, which can often be done in secret, with paternity never being able to be detected in ancient times; but for the female there is no hiding the fact that her child is hers, while the male desires a guarantee of fidelity. It is to the advantage of his DNA that no other male be allowed to mate with his female. The energy he puts into parenting does no good to his DNA legacy if he unwittingly raises another male’s offspring.

Another thing that makes males and females different in our species is our separate work roles (rare in nature), which evolved as hunting/gathering and do not occur in other primates yet are seen in nearly all primal human societies. Because of separate specialized work, males and females have evolved in some unique ways regarding socialization, communication, and brain specialization, even though overall intelligence for both is the same.

Without sex, we wouldn’t have the great variety of creatures that exist today, and many species would long ago have perished. And since sex is so important, much of what we do—everything from putting on makeup, to indulging in bar talk, to buying flowers, to making sure our hair is groomed, or that we’ve bought tickets to the play, all boil down at the evolutionary level to finding the best genes to insure our offspring will survive. But that doesn’t mean we have to be conscious of our motives (natural and sexual selection demand that we do not). So usually we’re oblivious as to why we do this instead of that. Most of what we “think” is through the subconscious anyway, some 95 percent. No teenager is dreaming of fighting potential parasites for their future young when they’re in a car somewhere having sex. But if we are engaging in all of this sexual activity in order be the fittest survivors in the game of natural selection, just who are we actually competing against? The answer to that question was originally asked and answered by Nicholas Humphrey. He said, “Selection within the species is always going to be more important than selection between the species.”3

We are competing against other human beings for the continuation of our genes—not lions and tigers: what counts in this race is who within the population of our species will be most successful in spreading his or her genes into the future. As David Buss, in The Evolution of Desire states, it was Darwin who first stated that sexual selection takes two forms:

In one form, members of the same sex compete with each other, and the outcome of their contest gives the winner greater sexual access to members of the opposite sex. Two stags locking horns in combat is the prototypical image of this intrasexual competition. The characteristics that lead to success in contests of this kind, such as greater strength, intelligence, or attractiveness to allies, evolve because the victors are able to mate more often and hence pass on more genes. In the other type of sexual selection, members of one sex choose a mate based on their preferences for particular qualities in that mate.4

Sexual selection is based on the principal that those members of a species who display features that translate fitness become the most sexually sought after. Thereby, those genes will be most favored in the mating game. If a female cardinal has evolved the notion that a really red male is the most desirable, she will go for the reddest cock she can find. But the most fascinating thing about this type of sexual selection is that when sexual traits are the ones being selected by members of a species, the force of evolution is no longer a random act shaped by mere survival. Intelligent choices are being made and exerted that shape the way a species evolves. This is selective breeding, similar to the way in which dog breeders have created everything from the Great Dane to the Labra-doodle from wolf stock. Through sexual selection animal species are altered by animal minds and the choices they make, and this includes the minds of our ancient ancestors, who by their sexual preferences created us. We are the end product of what they deemed desirable, just like a rhino is the end product of what its ancestors found attractive—a horn made of hair. And most of this choosing was done by females over every species, and for this reason, that females had so much power, scientists tended to disregard the great power of sexual selection, paying little attention to Darwin’s solution until recently.

The Sexiest Animals

Zoologist Desmond Morris calls humans the “sexiest animals alive.” Nature has given us the hard-wiring we need for sex to be foremost in our brains, and once the hormones kick in at adolescence our minds are abducted with dreams of dating and mating until the eventual point of reproduction occurs, at which time we then have to deal with the huge task of raising our progeny. Unlike other mammals, human females are receptive to sexual intercourse all year round, even when they are not fertile. In most species, a female comes into “heat” only at specific times of the year, during which time she signals through scent or visual stimuli—like the swollen sex glands of female chimps—that she is ovulating and ready to mate. But in humans ovulation is masked. We make a perpetual activity of sex—regardless of the calendar. As we age, sexuality continues for humans even into the eighties (marriage greatly facilitates this, with a greater decline for women than men). For men, sexual interest fades little (even if they are aging and experiencing erectile dysfunction—hence the booming profits of Viagra). And even though some women, as young as in their thirties and forties, report that they are no longer interested in sex once they are done desiring more children, at the same time most of these women will spend fortunes on products to keep them looking young, which from an evolutionary perspective equals giving off the right symbols of our species that imply fertility and sexual attractiveness. Women do not want to give up on love, and these beauty products are used as ways of tricking the male brain. Louann Brizendine, in The Female Brain, states that

worldwide, men prefer physically attractive wives, between ages twenty and forty, who are on average of two and a half years younger than they are. They also want potential long-term mates to have clear skin, bright eyes, full lips, shiny hair, and curvy, hourglass figures. The fact that these mate preferences hold true in every culture indicates that they’re part of men’s hardwired inheritance from their ancient forefathers. . . .

Why would these particular criteria top men’s lists? From a practical perspective, all of these traits, superficial as they may seem, are strong visual markers of fertility. Whether or not men know it consciously, their brains know that female fertility offers them the biggest reproductive payoff for their investment . . . over millions of years, male brain wiring evolved to scan women for quick visual clues to their fertility. Age, of course, is one important factor; health is another. A high activity level, youthful gait, symmetrical physical features, smooth skin, lustrous hair, and lips plumped by estrogen are easily observable signs of age, fertility, and health. So it’s no wonder women are reaching for the plumping effects of collagen injections and the wrinkle smoothing of Botox.5

Even if it’s not a conscious decision for sex per se, the underlying motivation for keeping as far as possible from showing signs of aging is to attract.

The whole business of being sexy for our species starts at puberty, or a few years before, when many girls begin to use cosmetics to enhance their natural physical attractors: such as lipstick (which has been used since ancient times). Desmond Morris theorizes that plump red lips (further exaggerated through additional artificial highlighting of them through cosmetics) physically mimics the labia, which during sexual activity becomes flushed with blood. “This is not, of course, a conscious imitation of the genital signals; it is merely ‘sexy’ or ‘attractive.’”6 The swollen breasts of female humans are another sexual attractor that begins to develop at puberty, something other primates lack. Chimps and gorillas have pronounced breasts only during lactation (apparently there is no relation between milk production and breast size) and most of the time are flat-chested. Human females display hemispherically rounded breasts constantly, due to genetically developed fat deposits. The female buttocks also undergo expansion during puberty (this in line with the more ancient display of the rump region, central for mating for all mammals except humans and bonobo chimps who, like humans, can also mate face to face). Once again, this is due to fat reserves that build up the buttocks at puberty. In Victorian times, the female bustle was a cultural exaggeration of the buttocks, while in other cultures, such as the Bushmen of Southern Africa, sexual selection has caused a condition known as steatopygia, in which the buttocks of the women are extremely pronounced and protruding, due to genetic selection, as if these women were wearing a bustle. For females around the world, body hair is also much less pronounced than that of men.

Men have evolved their own sexual attractors, such as facial hair, a strong jaw-line, greater height and musculature, a deep voice, and an Adam’s apple, caused by testosterone released in the womb shortly after birth and then later at puberty. In addition, because of our upright stance, the penis of male humans is displayed, which in other primates is usually not. Like us, in most other primates the penis is not endowed with any particular markings, though there are a few primates who do display it proudly and in bright color, such as the Mandrill Baboon. However, the codpiece, (or braguette in French) originating in the fifteenth century and lasting for two hundred years in fashion, was a cultural ornament of clothing employed in men’s pantaloons, originally as a flap that allowed men to urinate without removing their trousers, that quickly escalated into a fashion rage that included wildly protruding exaggerations of male genitalia of a variety of shapes that were even worn by royalty of various European countries. The greatest difference in the human male penis to other species, though, comes from the fact it does not contain a penis bone, as is found in most all mammals (which allows for an instant erection). Consequently, copulation for humans has taken a quite different turn, with sexual arousal becoming much less mechanical in our species and of much greater duration. At the same time, the penis is much wider and longer than in either chimps or gorillas, and able to stimulate female orgasms (a sexually selected trait, as human females over time preferred such peni). Human females are also endowed with a clitoris and the ability to have orgasms, something that our female primate cousins do not exhibit.

Ornamental Mind

Geoffrey Miller came up with a theory of the Ornamental Mind, which he developed after rethinking Darwin’s work regarding sexual selection. Miller believes that being endowed with brains that give us the ability to create infinitely flexible languages with copious vocabularies and artistic achievements of an endless variety—music, literature, ritual, drama, comedy, monumental architecture, and technology—as well as to partake in the daily range of emotions and thoughts—humor, empathy, sympathy, kindness, charity, religious thought—means that something was at work in our ancient ancestors that went far beyond such abilities in other primate species. “To Darwin, high cost, apparent uselessness, and manifest beauty usually indicated that a behavior had a hidden courtship function.”7 The Ornamental Mind Theory states that not only are the arts (including language and music) products of sexual selection, but so is the human brain itself. Our ancient ancestors, like all animals, were making decisions regarding mates. Females desired males who were tall, fast, strong, and dominant; males desired females who were youthful and fertile. But other traits were selected because they seemed sexy and desirable—the ability to make music, eventually speech itself, the ability to make nice things out of wood or rock, to crack a joke, to keep life from being a bore. Humans desired keen intelligence in other humans, as well as beauty and grace. Miller believes that sexual selection is the primary force that drove human intelligence, as choices were continually being made that led to smarter offspring: in the same way that peahens made choices leading to larger tails in peacocks. But in our species, men as well as women found big brains attractive, and relationships between males and females would alter drastically, giving both genders an equal footing when it came to intelligence.

Howard Hughes medical researchers have recently discovered hundreds to thousands of genetic changes “were acquired during the mere twenty to twenty-five million years of time in the evolutionary lineage leading to humans,” and “that selection has worked ‘extra-hard’ during human evolution to create the powerful” brains we have. Great leaps were made with “the appearance of the genus Homo about 2 million years ago, a major expansion of the brain beginning about a half million years ago, and the appearance of anatomically modern humans about 150,000 years ago.”8

A number of other physical forces had to alter as brain size increased, including the problem of delivery for the upright hominid female. Pregnancy is and always has been dangerous to women, for any number of problems can put the mother’s life at risk. As our ancestors went from walking like chimps and gorillas (knuckle-walkers) to standing up, enormous pressures were put upon the female body that made giving birth much more difficult than it had ever been before. As the brains of infants got larger, things got even worse. The pelvis could physically not become wider if women were to be able to walk on two legs. So the solution was for the infant to be born prematurely in order to make it through the woman’s pelvis. But growing that massive brain outside the womb also meant that the human child would be helpless for many years.

In most mammals it is the female, solely, who raises the young. But with children now dependent for years upon parents for sustenance, like many birds, our species began pair-bonding. Females needed help to make sure those children would survive. Those women with mates who stayed around to help raise the kids had a tremendous advantage, since it now took fifteen or more years for a child to become an adult. So women (like female birds) had to be very picky in their mating preferences, and it was advantageous for them to seek qualities in males that not only showed vigor, dominance, and strength, but also kindness and loyalty. Since males were more heavily invested in raising their helpless offspring, to make sure their DNA survived, and were now pair-bonding with females, they also began to seek kind and loving qualities in their mates, with whom they were now closely allied over a number of years. But while sexual selection can drive evolution it cannot create perfection, and every change is forged from a previous trait. Trickster tales reveal the fact that while we are capable of love and fidelity (in many stories Trickster has a wife), the underlying forces of promiscuity did not go away. Both from the male trickster perspective, of unleashed sexual appetite, to the female trickster, who must outwit the continual pawing and manipulation of the male, more than any other theme, trickster stories revolve around sex.