(Roman Genn)

Evolution, society, and the male propensity for violence

A friend once told me that being a man meant two things: taking care of your loved ones and burying your dead. Everything else flows from that.

If only it were that simple. Always hard to define but easy to flunk, manhood has become even more fraught in recent years. A slew of sexual-assault and -harassment claims have been leveled against men in Congress, Hollywood, and various industries. “Rape culture” allegedly pervades even the most progressive college campuses. And the country is closing in on two decades of war that have been promulgated almost exclusively by male politicians giving orders to male generals who go on to command all-male combat units. In that atmosphere, the question of manhood — what it means, how it is achieved — seems impolite to bring up. A few years ago I asked a young man that question, and he looked at me in alarm and said, “Are we even allowed to talk about that?”


The forgivable idea that manhood is morally suspect has been around at least since I was in college in the 1980s. I remember walking across campus with my girlfriend one morning to find, nailed to trees, signs that declared, “All sex is rape.” Perhaps the sentiment was not meant to be taken literally, but it still seemed to suggest that maleness was a kind of original sin that could never be fully expunged. Now in my mid fifties, I was surprised to see that idea still lurking in a New York Times article titled “The Unexamined Brutality of the Male Libido.” (To be fair, the piece was roundly criticized by Times readers.) Around the same time, I was in a café in New York City and overheard one young woman say to another, “This binary idea that there are good dudes and bad dudes is bullsh**. They’re just dudes. And they’ve all been socialized badly.”

Ignoring the fact that a lot of early socialization is done by mothers and female kindergarten teachers, those two young women might have a point: The vast majority of murders, assaults, rapes, armed robberies, and threats to the public safety are committed by young men. Most men are not criminals, of course, but a huge majority of criminals are men. Men make up 93 percent of the American prison population, and young men die from accidents and violence at up to six times the rate of young women. The cause is not just poor socialization, however: Male violence is a problem across all societies, communities, and races, and the primary driver is testosterone, which declines steadily throughout a man’s adult lifetime. As testosterone levels go down, so do rates of violence and accidental death — which would not be the case if socialization alone were to blame.


But given these appalling statistics, it’s not uncommon to hear well-meaning people declare that if women ran the world, it would be a better place. Granted, the sex that contributes nine out of ten inmates to our nation’s prisons might not be the best choice for controlling the levers of power, but that doesn’t mean that the kinds of women who want to run the world wouldn’t bring their own problems to it as well. People who say that they want women to run the world presumably mean good women — as opposed to Imelda Marcos or Mary Queen of Scots. But if “good” is a requirement, why bring up gender at all? Would liberal feminists really vote for Sarah Palin over Bernie Sanders? Conservative feminists for Nancy Pelosi over Paul Ryan?


Perhaps what these people mean is that a world run by women might be less violent than a world run by men for the same reason that women’s prisons are less violent than men’s prisons: Women tend to be more collaborative and compromise-seeking than men. That immediately breaks down when women feel threatened, however. During the American Civil War, women in the South publicly shunned men who had not enlisted in the Confederate forces. And I watched a similar process in Sierra Leone when word came that rebel forces were advancing on the jungle town of Kenema. Women began exhorting men to defend them, and the men dutifully rushed off with whatever weapon they could grab — cutlasses, shotguns, clubs, old rusting AKs. Nothing pacifist or collaborative about the women at all.


But those wars were started by men, one might say — wouldn’t eliminating men from power keep such wars from starting in the first place? Perhaps, but that wouldn’t keep famines and droughts and earthquakes from setting populations into direct competition with one another. And throughout the primate world, males are physically better at defending a group’s scarce resources because they are larger, stronger, and faster on average — and unburdened by pregnancy or young offspring. Furthermore, men are eminently disposable; kill most of the men in a society and it quickly recovers, but kill most of the women and it dies out within generations. Because of all these factors, a common definition of manhood throughout history has been a willingness to put the safety of others above one’s own. (As anthropologist Joyce Benenson put it to me, “The definition of a man is someone you can count on when the enemy comes.”) Male violence encourages women to partner with males who are able to defend them — an evolutionary irony that is clearly self-perpetuating.

This is where biology might help. Although gender is a cultural concept that is in constant flux, sex is not. Sex traits, such as women having less body hair or men having more testosterone and bigger muscles, are the product of millions of years of evolution. Humans split from chimpanzees 6 million years ago and have been shaped in large part by what each sex found desirable in the other. Individuals with desirable traits were more likely to pass their genes on to the next generation, so those traits gradually spread through the population. As a result, there is no way to discuss what men are, biologically, without addressing what women choose, sexually. Evolution works so slowly that humans have not changed in any significant way in 20,000 or 30,000 years; a baby born to parents who hunted woolly mammoth in Europe is biologically indistinguishable from a baby born yesterday. There are limited adaptations in certain populations, of course — lactose tolerance or malaria immunity — but as a species, we are still trapped in our Ice Age bodies and our hunter-gatherer minds.



Given the level of violence in human history, then, it’s not surprising that many studies show a female preference for partners who can protect them. A 2015 report in Human Ethology Bulletin, for example, found a strong correlation between a woman’s self-reported vulnerability and her sexual preference for aggressive men. And even women who do not feel threatened still strongly prefer men who exhibit a capability for protection and violence. Studies have also shown that deep-voiced, high-testosterone males are preferred by women of reproductive age but not by middle-aged women. And the preference for high-testosterone men spikes when women are ovulating — which can be problematic when women choose partners while on birth-control pills and then go off them to get pregnant. Finally, a 2015 study in Evolution and Human Behavior found that when women at a British university were shown photographs of young men, they consistently rated men with combat medals as more attractive than other men; a different study, published in Personality and Individual Differences, showed a similar result for facial scars.

These studies don’t describe how all women choose their mates; they simply show a bell curve of preference for aggression and dominance. (And women use many criteria for selecting a mate — including, apparently, “storytelling ability.” Nature reported in 2017 that good raconteurs father disproportionately more children among the Agta, a hunter-gatherer population in the Philippines.) But on average, dominant, high-testosterone males regularly out-compete subordinate males for sexual opportunities. That creates a problem, though: Men who are hormonally predisposed to violence make great warriors but dangerous partners and fathers. To counteract that threat, men experience a significant drop in testosterone when they become fathers — and even when they hold a child. Female preference for high-testosterone males, coupled with a drop in male aggression around children, may be an evolutionary balancing act that allows the maximum number of children to survive.


This hormonal component of male behavior is then greatly amplified by social conditioning, and the two combine to affect behavior in spontaneous, unconscious ways. During the mass shooting in Aurora, Colo., four of the twelve victims were young men who died protecting women with their bodies; there were no examples of the opposite. (Women are well known to protect children — as one brave teacher did during the Sandy Hook massacre — but examples of women using their bodies to shield male partners are vanishingly rare.) And one study found that 90 percent of “bystander rescues,” in which a person tries to save a stranger, are performed by men. One in five rescuers dies in the attempt, but heroism may pay off: A recent study found that Medal of Honor recipients from World War II went on to have significantly more children than unrecognized combat veterans from that war, after other variables were adjusted for.

Even a society such as ours, one that aspires to gender fairness, harbors differing expectations for the sexes. Both men and women blithely use the phrase “Be a man about it” despite the fact that our vernacular has no female equivalent. This is not because women are thought to be dependent and juvenile; quite the contrary. Despite the many unfair standards applied to women, their status as adults — particularly after childbirth — is simply not in question. Not so for men. The stubborn persistence of phrases such as “Man up” and “Be a man about it” imply that it’s possible to be an adult male and yet fail the societal definition of manhood. An acclaimed 2014 film called “Force Majeure” portrayed the marital aftermath of just such a situation. Threatened with an avalanche at a ski resort, a man grabs his cell phone and runs for his life rather than stay with his wife and children. The wife tries to forgive her husband but can’t, and the marriage collapses.

But in a safe, affluent society such as the United States, men rarely get the chance to pass the “avalanche test,” so they must rely on more mundane ways to define themselves. Until recently, one easy definition was whether you did the work assigned to men; likewise for women. The sexual division of labor reaches far back into our primate origins but seems to be diminishing. Because of testosterone men have, on average, about twice as much upper-body strength as women. That has long made them capable of doing jobs that women may struggle with. Hydraulic power and the internal-combustion engine have obliterated those differences, however; a woman on a backhoe can move just as much earth as a man on a backhoe. Cultural hurdles remain, but at least the physical barriers to those jobs have been largely removed.


As these gender-specific jobs disappear, it becomes harder for men to know whether they have anything essential to offer society, and the ramifications of this are profound. Humans don’t survive alone in nature; they die — and as a result, we are all hardwired to belong to groups. But the only way to guarantee membership in a group is to be needed by it, so being unneeded can feel catastrophic. Other groups show how this can play out. The national suicide rate is known to closely track unemployment, for example, and after the economic collapse of 2008, around 5,000 additional people in 54 countries committed suicide because they had lost their jobs. These were people who no longer felt needed. A similar phenomenon can afflict retirees and military veterans, and perhaps even men discharged from close-knit communities such as firehouses or sports teams.

Further troubling the waters are terrible stories of sexual assault and harassment in the workplace. The obvious question is why sexual wrongdoing — but not corruption or other abuses of power — is an almost exclusively male problem. Unfortunately, the answer probably lies in the fact that evolution has always incentivized men to act aggressively. An estimated 8 percent of Asian men are directly descended from Genghis Khan, arguably making him the most genetically successful man in history. But communities do a very good job of policing themselves, in part because men are highly incentivized to both act well and to confront those who don’t. If Hollywood or Congress were healthy communities made up of a rich matrix of family and social bonds, predators simply couldn’t get away with the kinds of assaults that occur regularly in modern society.

Which brings us back to what it means to be a man. Unlike men, women know with absolute certainty that their children are their own, and each child represents a huge chunk of a woman’s reproductive potential. As a result, it’s very easy to get women to emotionally invest in their children. Men, on the other hand, are stuck taking paternity on faith and have been programmed by the implacable math of evolution to impregnate women and keep moving; their reproductive potential is limited only by the number of sexual partners they have. That makes fatherhood a poor measure of manhood; plenty of good men don’t have children, and plenty of bad fathers have made enormous sacrifices for their community or their nation. So in our modern age, how does a man demonstrate his worthiness — his manhood — if he has no children to raise and no enemy to fight?

Both the triumph and the tragedy of modern society is that we have eliminated almost every hardship and danger from daily life. For the most part that is a great blessing, but it comes at a cost. The very efficiency of mass society makes people feel unnecessary, and therein lies a profound threat to our dignity. The poor are dehumanized by the menial jobs and shoddy urban housing they often wind up in. The rich are dehumanized by the very privilege and luxury that they use to insulate themselves from everyone else. The middle class is dehumanized by the cookie-cutter suburban homes they have mortgaged their futures for. The old are dehumanized by the speed and complexity of the mechanized world. The young are dehumanized by the wholesale substitution of social media and video games for real human experiences. And every last one of us is dehumanized by a society that uses algorithms and mass communication to feed us the truths we prefer and the lies that we need.

A new use for manhood may simply be to protect our precious human dignity at every possible turn. That’s hard to define and happens in both large ways and small, but it’s unmistakable when you see it: The man who stopped the column of tanks at Tiananmen Square in 1989. The tank driver who refused to drive over him. The Latino worker who offered me a seat on the subway because I was holding an infant. The struggling business owner I reported on who quietly forsook a year’s salary so he wouldn’t have to fire anyone. And finally, this: A fit old man in a wheelchair whom I saw trying to get into his car outside a hotel in Norfolk, Va. His right leg ended in a mass of bandages at the knee.


“That seems really difficult,” I said, after he declined my help.

“It’s interesting,” he acknowledged.

“You seem really brave about it.”

He looked at me like I was the biggest fool he’d met all week. “There are young men in this country missing both legs,” he said. “Don’t call me brave.”

What these men all have in common is that they put the welfare of others ahead of their own. Some were willing to die for it and others were just willing to stand for an hour on a crowded subway, but regardless, they were thinking firmly outside themselves. In that sense, the definition of manhood hasn’t changed, but the enemy has. For the first time in history, it’s starting to look very much like us.