Everything You Always Wanted to Know. . .

Pardon me, but are you a sex machine?

When the singer James Brown declared himself a sex machine, he didn’t get much argument, especially from hard-core Darwinian biologists. From their perspective, yes, we’ve all been engineered to breed.

The godfather of soul achieved immortality with a primal screech and a thrust of his loins, but for most of us that’s just the beginning. In our bid to live forever, we’re driven to mate, then spend our best years raising kids we hope will be crazy enough to repeat the process. Weirdly enough, they usually do.

Though the wild thing has its pleasures, our fondness for it is not fully understood. Nor is nature’s. Scientists call this the “paradox” of sex, noting that there are other, far less messy ways for life to reproduce. Given its huge cost in terms of energy and risk to the individual organism, why do we bother, when all we may be passing on is the cleft in our chins? Our excuses come and go. Every era spins its flimsy rationales, then calls on the power of myth, religion, and the law to etch them in stone. They never last.

The current trend is to blame our obsession with sex on those imperious packets of living data known as genes. All creatures are programmed to reproduce according to the rules of natural and sexual selection — life’s version of the killer app. Modern biology and, increasingly, psychology are influenced by evolutionary theory. On one extreme, the so-called neo-Darwinians would say that everything we do is an expression of the genetic algorithm embedded in our cells.

But as suggested below, our carnal knowledge is being shaped by other influences, including evolutionary models that aren’t so coldly mechanistic. If nothing else, these ideas and theories are a telling reflection of the times. In groping for the universal truth of sex, it’s a well-known fact that every age ends up making love to itself.

1. Are humans monogamous?

No, monogamy is human. It’s one of many sexual strategies we practice, and seem destined to continue practicing, until we get it right. Surveys say that as many as half of all American men report having had extramarital sex at least once. The rate among women is said to be one in three, though they’re also apparently more prone to fib about it.

We’re not the only animals with a taste for sexual novelty. Thanks to “genetic fingerprinting” techniques that can determine parentage, researchers have found more cheating in the wild kingdom than on country-western radio. Even among species that once were thought to practice fidelity, it turns out scientists were often seeing what they wanted to see. “The pattern is painfully clear,” write zoologist David P. Barash and psychiatrist Judith Eve Lipton in The Myth of Monogamy. “In the animal world generally, and the avian world in particular, there is a whole lot more screwing around than we had thought.”

Faced with evidence that females are just as randy as males, some evolutionary biologists say “sperm competition” may be the reason. Imagine a cross between water polo and The Bachelorette. If sperm are seen as fighting it out among themselves for the right to fertilize an egg, it figures that females benefit (via better offspring) from having multiple partners, too.

Humans have a long history of not looking too closely at paternity, but the new genetic lie detectors may change that. As Barash and Lipton note, the “monogamous family is very definitely under siege, and not by government, not by a declining moral fiber, and certainly not by some vast homosexual agenda . . . but by the dictates of biology itself.”

2. Does size matter?

Yes, and so does shape, if you believe the evolutionary biologists who say the human penis evolved both to implant sperm and to extract someone else’s. Comparisons to pistons and plungers are slung with a certain suspicious zest among this crowd, as is the fact that, among primates, men are the most amply endowed. On this score, Barash and Lipton are not entirely convinced: “If sperm competition has been so important in producing men’s anatomy, especially the seemingly oversized penis, why do men have proportionately smaller testicles than chimps?” Well, exactly.

Among evolutionary psychologists, Darwinian competition is called upon to illuminate every aspect of human behavior, including the supposedly age-old male anxiety about penis size, if not the invention of clothes. As long as we’re comparing, let’s cast a furtive glance at those who were quite comfortable wearing nothing at all. In Looking at Lovemaking: Constructions of Sexuality in Roman Art 100 B.C.-A.D. 250, author John R. Clarke notes that the ancient Romans and Greeks viewed small penises as the aesthetic ideal. Clarke, an art historian, stresses that the classical world had “a sexual culture that operated under rules completely different from our own.” We may be mystified by how a bathhouse fresco of a well-hung guy could have the average Roman in stitches. Then again, imagine their puzzlement over a cartoon of an evolutionary psychologist caught in bed with a student saying, “I can explain everything!”

3. Why are some people always attracted to the wrong lovers?

It’s better to see the glass as half full and be grateful that we’re so often attracted, at least, to the right species.

4. What do women want?

Iron. Human evolution has been driven by the female need for the dietary iron they largely got from meat.

Or so argues the surgeon and writer Leonard Shlain in the new book Sex, Time, and Power: How Women’s Sexuality Shaped Human Evolution (Viking). Drawing on medicine and other fields, Shlain creates an intriguing scenario for how modern humans suddenly appeared in East Africa 150,000 years ago, then fanned out to dominate the earth. In his view, the human female was the first to push the species into a sudden evolutionary spurt beyond our immediate ancestor, a somewhat duller biped known as Homo erectus. What’s more, Shlain suggests that males have never quite forgiven the other sex for wrecking the party.

Along with our bigger heads and brains, the female of this new species developed a unique set of reproductive traits, including periodic menses that were attuned to the phases of the moon. For complex reasons, these various changes gave women an unprecedented control over when (or if) to reproduce, thus breaking what Shlain calls the age-old “sexual monopoly” enjoyed by the strongest males.

But their new power had a price. Periodic blood loss drained women of iron, an element crucial to life, especially fetal development. That might have doomed our species if not for the adaptive edge it gave us in return. Shlain theorizes that females used their bodily rhythms to develop one of our greatest intellectual skills — a sense of time — then shared it with males to make them better hunters. What did women want? The iron in meat. Which men bartered for what they wanted.

This sexual economy may have fueled the creative tension that made us what we are today — a brilliant predator with a split personality. Shlain suggests that “males have spent the last 150,000 years trying to regain the power they so emphatically lost to females” when women discovered the power of saying no, and maybe. One result is misogynistic rage; another is the male capacity for what otherwise is nearly nonexistent in nature, fatherly love. Go figure.

5. What do men want?

Generally, anything that will distract them from ever having to visualize “sperm competition.”

6. Are people having more or less sex today?

With the human population surging past 6 billion, we can say that people today are more or less having sex, and leave it at that. It’s a frisky planet.

7. How many genders are there?

A trick question. Certain feminists and queer theorists have argued that what we call gender is really a kind of performance. Meanwhile, scientists disagree over just how flexible our sexual identities really are — a debate played out famously in the case of a boy born in 1966 who lost his penis in a medical accident and was unsuccessfully “reassigned” to be a girl. Meanwhile, geneticists will tell you that male and female traits get mixed in every imaginable way, including creatures split right down the middle

So how many genders are there? Two: the gorgeous young, and everyone else.

8. Is homosexuality natural?

Yes. Homosexuality abounds in nature. Indeed, homosexuality is nature at its enigmatic best, in that it reminds us how little the natural order gives a damn about what humans think they ought to be.

Same-sex activity between animals (and between animals and humans) has been portrayed in human art since the cave paintings at Lascaux. Though earlier peoples wove their knowledge of homosexual and transgendered animals into ritual and lore, modern scientists were slow to accept how common these phenomena were. Now that it’s been well documented, nature’s flamboyance is clearly a challenge to religious fundamentalists. Less obviously, the reductive view of sex held by certain hardcore neo-Darwinians may also need rethinking.

The evolutionary psychologist Geoffrey Miller hints at why in The Mating Mind: How Sexual Choice Shaped the Evolution of Human Nature. In Darwinian terms, the survival of homosexuality makes no sense. “Any genetic propensity towards exclusive homosexuality would have been eliminated in just one generation of selection,” he writes. Its existence in modern humans “is a genuine evolutionary enigma that I cannot explain.”

Some say the mystery will never be solved until we’ve developed a new post-Darwinian evolutionary model. It may be in the works. In Biological Exuberance: Animal Homosexuality and Natural Diversity, biologist Bruce Bagemihl argues that, given all of the apparent “purposelessness” of so much sexual activity in the wild, scientists have to rethink their basic models of what sex is all about. “Contrary to what we’ve all been taught in high school,” he writes, “reproduction is not the ultimate ‘purpose’ or inevitable outcome of biology.”

9. What then is the purpose of sex?

For Bagemihl and others, sex is life’s celebration of its own gaudy excess. What he calls “biological exuberance” is, above all, “an affirmation of life’s vitality and infinite possibilities; a worldview that is at once primordial and futuristic, in which gender is kaleidoscopic, sexualities are multiple, and the categories of male and female are fluid and transmutable.” Brilliant birds, iridescent fish, wrestling Greeks, Ingrid Bergman’s face — it’s all part of a crazy parade weaving out of the past, bound where we do not know. Sex is life’s swaggering boast that it’s got the mojo to weave and slither around any barrier time throws in its way.

Jeremiah Creedon is a senior editor at Utne.

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