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The Human Ape

Our animal nature is undeniable. But is beastly behavior inevitable?

I write on the morning of November 29, 2017, knowing that, by tonight, any list I could make of powerful men who stand accused of sexual harassment or assault might be obsolete as more women step forward. (NBC's Matt Lauer was added as I typed this.)

Senator Al Franken press kit
Source: Senator Al Franken press kit

The accusations against some of the accused men don’t surprise me. But those by KABC anchor Leann Tweeden against Al Franken do. The LGBTQ community, Planned Parenthood, conservationists, and The American Civil Liberties Union all have a friend in Franken.

Franken admits to the Tweeden allegations. He has called his behavior disgusting.

Damn it. Why do even the good guys act like apes?

They actually are apes.

Ask any ethnologist or anthropologist and he or she will assure you that humans are Great Apes. We share about 98.8 percent of our DNA with chimps and bonobos, which together make up the pan-species.

This means that humans have the same reproductive imperatives that animals in general—and pans in particular—have. The job of the male is to spread his seed as widely as he can. The job of the female is to be selective about whose seed she receives.

Which is to say that humans’ biological blueprint lays out dramatically different sex roles for men and women. Human men may not think in terms of fathering as many babies as possible, but their hormones make them go whole hog for copulation at almost any opportunity. On the other hand, women’s hormones lead them to be choosy and even to recoil at times in disgust.

And therein lies one explanation for the many recent headlines about sexual misconduct by men. Powerful men behave like the animals they are. At the same time, the rules of the game in our society have been constructed mostly by men. This means that, when women exercise their animal right to say, “No,” men don’t necessarily have to listen.

Our animal nature is undeniable. But is beastly behavior inevitable?

The answer may lie in a look at the animal side of the evolutionary tree.

Very roughly speaking, single cells animals begat fish, who begat land animals, who begat primates, who begat Great Apes when they diverged from gibbons about 15 million years ago.

Then orangutans diverged about 13 million years ago. Orangutan females are a fairly glee-less lot. Because everyone in the species lives alone, females are easily victimized. In the early 1980s, University of Michigan anthropologist John Mitani closely observed three females. He witnessed 179 copulations over a six-month period. A male initiated all but one, and often the first copulation between any given male and female was a rape.

In Demonic Males, a 1996 book he co-authored with Dale Peterson, biological anthropologist Richard Wrangham noted that, once a gorilla male has raped a particular female, she is, in general, more acquiescent to him during later encounters. Orangutans are smart. Wrangham guessed that females quickly learn that resistance is futile.

Gorillas split off from the orangutan species about 10 million years ago. They live in groups, which may account for why outright rape is rare.

But here’s female gorillas’ awful truth. They don’t just get impregnated by a male and go on to raise their progeny; they mate long-term. And sometimes, when a male gorilla wants to attract a female away from her current mate, he kills her infant. Afterwards, she willingly runs off with him.

What is it about infanticide that makes it a sexual come-on? Wrangham and Peterson have speculated that, in gorilla society, a female and her young are probably safest when under the protection of the biggest, baddest gorilla around. When a female’s infant is murdered, she knows without a doubt that she has found a truly mean male. So she “trades up” by pairing with him. Yes, he killed her baby. Yes, he can do her future children just as much harm—but he will probably protect them instead because they will be his children.

Pans (chimpanzees and bonobos) developed into their own species about six or seven million years ago. Male chimpanzees brutally dominate females. Rape is common. But fertile females are often willing sexual partners.

Indeed, fertile females’ promiscuity is impressive. Sometimes a female will mate with all of the males in the group in a single day. Wrangham and Peterson have suggested that this may be in order to create confusion about paternity. Chimps, like gorillas, practice infanticide. And if virtually any male in the group could be the father of a particular child, perhaps no male in the group will kill that child.

Most male primates know when a female is fertile because her labia become red and swollen. For chimps, it’s no different. Estrus lasts only two to three days out of the approximately 30-day menstrual cycle. So when a female shows the fertility sign, males are all over her and by and large, she is under them.

For bonobos, though, the signs of estrus extend well beyond when a female is actually fertile. Maybe that’s why males don’t respond all that eagerly to swollen labia. They really don’t need to; they can easily get around to having sex with any fertile female anyway.

Both male and female bonobos have sex freely and joyfully as often as they like and with virtually anyone they like. Homosexual encounters are as frequent as heterosexual ones. A male might rub his scrotum against the buttocks of another male. Two males might engage in what ethnologists have dubbed “penis fencing.” The males hang face to face from branches and, while dangling, rub their erect penises together. Bonobos’ unusually large clitorises facilitate female-on-female sex. When two females have sex, one stands and lifts the other. Hugging, they rub their clitorises laterally against each other while they grunt and squeal. Then they clasp each other even more tightly and shudder.

In general, though, both male and female bonobos are inventive about sex. Unconfined to any “script” they can engage their mouths, toes, and fingers virtually anywhere they fit and feel good.

Given the frequency and apparent freedom of bonobo sex, would it qualify as “meaningful” in the way that human mothers often warn daughters sex is supposed to be? Actually, it does. Bonobos use sex to create alliances that can see them through hard times. Powerful, protective female dyads and gangs are formed that way.

The men never really get around to forming pacts with females or males, but they do enjoy themselves greatly—if fleetingly. On average, bonobo sexual encounters last only 13 seconds.

Females are dominant in bonobo society. When a male attempts to be sexually coercive, “no” means “no,” and a gang of very angry, sexually beholden to no one females stands at the ready to defend his intended victim.

Hominids separated into a new species at about the same time as pans did. Anatomically modern humans—Homo sapiens—came on the scene between 100,000 and 200,000 years ago.

Are modern human males as sexually animalistic as their ancestors? Today’s rape statistics vary by culture and by data collection method. But, according to the Centers for Disease Control, nearly one in five American women report being raped at some time in their lives. While infanticide happens all too frequently in America, it probably isn’t usually instigated as a mating come-on. Which is to say that American women fare far better sexually than female orangutans and gorillas.

The Human Ape

Humans evolved much more quickly than any of their primate cousins or ancestors. All pans, for example, are pretty much the size and weight their ancestors were when the pan line split off from the Great Ape evolutionary branch. But humans look very different than they did six or seven million years ago. And some can do cool tricks like flying to the moon.

One common explanation for the rapid evolution of humans is that hominids became a separate species because their territory became drought stricken. Those who survived the great drought did so by figuring out to stop lazily counting on fruit to appear. Instead, they dug for roots. Ultimately, as their part of the jungle became woodland, they incorporated a wide array of new foods into their diets. Early humans learned to dig, but they also learned to hunt, hammer with increasingly refined tools, and cook. As they developed the technologies to accomplish necessary tasks, form followed function. Their bodies changed and their brains got bigger.

These days, while orangutans, gorillas, and pans continue to pluck jungle fruit, we humans invent and re-invent our technologies and even our cultures almost ad nauseum. We devise laws and we codify punishments for a spectacular array of specific misbehaviors.

“I went at her like a bitch.”

Our president said that. That may be because he’s a particularly ape-ish Great Ape, as Harvey Weinstein probably is. Oh. And Al Franken.

But to what extent should we accept the idea that all ape-ish sexual behavior is equally loathsome? Is Franken a Weinstein? The most pressing problem we want to address isn’t gross insensitivity, is it? It’s raw abuse of physical, economic, and emotional power to sexual ends.

So, what about clumsy and sometimes disgusting approaches perpetrated by men who, like bonobos, seem to assume that everyone is up for sex 100 percent of the time, and stick their tongues and hands in all the wrong places? What about Al Franken’s several admitted and decidedly bonobo-like attempts at 13 seconds of erotic flame?

Rose is a Rose

A 2014 paper from the University of North Dakota reported that 31.7 percent of college men surveyed in 1980 allowed that, in a consequence-free situation, they’d force a woman to have sexual intercourse.

At the same time, only 13.6 percent said they would rape a woman.

Look at that 20-percentage point spread. What’s the difference between forced sex and rape?

Of course, there isn’t one. Helpfully, the researchers noted that, “When, instead of using labels like ‘rape,’ survey items ask questions about behaviors, more men admit to the behavior that the label describes. For example, ‘’Have you ever coerced somebody to intercourse by holding them down?’ elicits more ‘yes’ answers than ‘Have you ever raped somebody?’’’

This reminds me of the excuses we’ve heard recently from the lawyers of accused men. Often they claim that their clients are aghast to learn that not all of the sex they’ve enjoyed was consensual.

Even Al Franken initially said, “I certainly don't remember the rehearsal for the skit in the same way, but I send my sincerest apologies to Leeann.”

In his later, full statement, Franken got more to the point. “Over the last few months, all of us—including and especially men who respect women—have been forced to take a good, hard look at our own actions and think (perhaps, shamefully, for the first time) about how those actions have affected women.

"For instance, that picture. I don't know what was in my head when I took that picture, and it doesn't matter. There's no excuse. I look at it now and I feel disgusted with myself. It isn't funny. It's completely inappropriate. It's obvious how Leeann would feel violated by that picture. And, what's more, I can see how millions of other women would feel violated by it—women who have had similar experiences in their own lives, women who fear having those experiences, women who look up to me, women who have counted on me.”

The eloquence of that apology helps a bit with my feelings of profound disappointment about Franken. And thinking of him as a boorish, occasionally unzipped, but not sexually coercive Great Ape makes me imagine that he deserves strong censure, but not the loss of his Senate seat. Perhaps there’s a significant difference between a dunderhead’s shenanigans and those of men who are violent or use their positions of power to get what a woman would rather not give.

I do wish, though, that we could get a horde of our bonobo sisters together to teach Al Franken a lesson. With luck, what the media do to him as he returns to the Senate will substitute nicely. And, of course, the Senate’s Ethics Committee will dig, and that’s all good.

We are left for the time being with Franken’s full-throated apology. If nothing else it has given American men an opportunity to examine their apish behavior and find words with which to reach out to women they’ve harmed.

I only hope that, in doing so, men everywhere take no cues whatsoever from their bonobo cousins.

How do bonobos apologize, you might ask? They kiss and quickly initiate sex.


Dale Peterson and Richard Wrangham, Demonic Males: Apes and the Origins of Human Violence (Mariner Books, 1996).

[No author or date], Sexual Violence, CDC website,

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