Sex, Power, and Partisanship: How Evolutionary Science Makes Sense of Our Political Divide - Hector A. Garcia 2019

Shared Genes, SDO, and Male Violence
Equality Versus Hierarchy

As Ismael the Bloodthirsty's five hundred concubines and 888 children evince, men are driven by personal reproductive ambitions. However, amassing power requires alliances. Moreover, because men in more violent times stood the risk of being annihilated by rival male groups, they had great incentive to form warring coalitions. Men unable to do so would be ground into dust. This dynamic, which makes the maxim join or die a rather literal evolutionary imperative, forged a powerful selective pressure. And so today we see group-level violence between men across many levels of human social organization, from intertribal conflicts to gang fights to world wars.⁶⁰

While rarely discussed, shared genes have a role in male intergroup conflict. British biologist Richard Dawkins popularized the idea of a gene-centric view of evolution in his book The Selfish Gene.⁶¹ Dawkins explained how genes design organisms in ways that maximize their own reproduction, and went so far as to say that organisms are the “survival machines” of genes. One common means of understanding this relationship is by considering the impact of genes in acts of altruism—acts that may endanger the life of one individual in the service of helping another. The willingness to perform such acts is generally highly correlated with the amount of shared genetic material. Hypothetically, if I were going to save someone from a burning building, I would save my child first, my cousin next, an unrelated stranger after that, and I might just leave my pet goldfish to boil—or, as British geneticist J. B. S. Haldane famously said, “I would lay down my life for two brothers or eight cousins.”⁶² Thus genes code brains to engage in behaviors that ensure more copies of themselves get passed on across time, even if those genes reside in others. That said, when I burst into a burning building, I'm not consciously thinking of my genes. But my genes make my brain experience an intense sense of emotional, cognitive, and moral urgency to save my child first.

Patterns of migration appear to have intensified moral commitments between men. Historically, humans have been mostly patrilocal, meaning women have left their natal group far more often than men, whereas men stayed put along with their male relatives. Research has found that up to 70 percent of all human societies follow this pattern of emigration.⁶³ The resulting concentration of male blood relatives encouraged naturally strong, trusting, and cooperative male bonds based on shared genes. Accordingly, across human history, men have had stronger kinship ties than women.⁶⁴ The love and trust that related men have for one another has had profound implications for the human condition across time.

For one, higher relatedness gives men greater confidence in risky cooperative enterprises, such as war, with closer kinship providing genetic incentive to take risks in defending one another. As a corollary, research has found that patrilocality in human groups is associated with more frequent warfare.⁶⁵ This too is a pattern that human males share with our chimpanzee cousins. Renowned primatologists Richard Wrangham and Dale Peterson write that among four thousand mammals, and over ten million other animal species, only chimpanzees and humans follow this pattern of patrilocality accompanied by “a system of intense, male initiated territorial aggression, including lethal raiding into neighboring communities in search of vulnerable enemies to attack and kill.”⁶⁶

Further, the hostility created by patrilocality locks us into patrilocality. Chimpanzee males, for example, are so extremely hostile toward outside males that males rarely if ever transfer between groups; any male attempting to transfer would be summarily killed by the males of the out-group. By contrast, 50—90 percent of female chimpanzees transfer to other groups to breed once they reach sexual maturity.⁶⁷ Whereas male transfers are seen as sexual competitors carrying foreign genes, females are welcomed as potential mating partners.

Male transfer is more common among humans than chimpanzees but still not the predominant pattern—like male chimps, men are hostile to strange men. Thus xenophobia is concentrated among men, and it has reflected real dangers for men. Most of the world's perpetrators of violence are men, but most of its victims are as well (the United Nations, for example, recently found that globally 80 percent of homicide victims are men⁶⁸), and this pattern of killing is very old. Male-on-male violence persists particularly among humans living in groups similar to those of our ancestors. Archaeologist Lawrence Keeley examined contemporary foragers across the world, such as the Jivaro, Yanomamö, Mae Enga, Dugum Dani, Murngin, Huli, and Gubs, and found that male-on-male violence accounted for a whopping 30 percent of all male deaths.⁶⁹ If this population of men were all five boroughs of New York City, roughly the population of Brooklyn would be annihilated. The resulting fear of out-group males perpetuates the cycle of violence, for, as we learned in chapter 2, xenophobia promotes inbreeding. Inbreeding increases the degree of shared genes in a population, which in turn increases xenophobia, further locking humans into patrilocal, xenophobic, patriotic groups of violently competing male primates.

The cycle of xenophobia has held strong even with our shared genes thinning out as populations swell. Military men exaggerate genetic relatedness by calling themselves “brothers-in-arms” fighting for their “fatherland” or “motherland.” And fighting men have reported feeling closer to their fellow soldiers than to their own wives,⁷⁰ which suggests that our long history of patrilocality may have greased the way for contemporary male tribalism. Even modern-day men living as civilians in peaceable societies have the tendency to fall back into these patterns, which have proven easy to elicit in the research lab. When experimenters posit an outside threat, men close ranks, identify with their group, and start cooperating more, whereas this response is generally not found among women.⁷¹

An important point in all this is that if ancestral human men couldn't leave their groups for fear of death, then turning inward to their band of brothers, remaining xenophobic toward outsiders, and favoring dominance over other groups was evolutionarily sensible. The overrepresentation of men among conservatives and the preponderance of male interests embedded in conservative ideologies, then, reflect these ancient selection pressures on men.

Certainly, in a dangerous world, with groups of men amassed on the border, waiting to annihilate my tribe, I would want to be surrounded by a close-knit, aggressive, xenophobic tribe of men. Similarly, if my children and I risked starving to death without access to a contested resource, I would want my tribe to win control. Once again, the question remains, however, how much utility this psychology retains as we move from small tribes competing for scarce resources to an interconnected community of nations, bound by a global economy, and with the technological capacity to erase starvation from the human experience.

Moreover, evolutionary science teaches us that inequality is often driven by the personal reproductive ambitions of men. Man's exorbitant reproductive capacity has given him incentive to disproportionately hoard power, wealth, and women, and, when allowed, to use despotic violence as a means to this end. So the impulse to extract wealth from the rival tribe is about not only survival but also feeding insatiable male reproductive greed. When we understand these roots of inequality, we may begin to question how far we allow them to influence our economic policy. But merely posing this question can be challenging. Across our history, powerful men have achieved godlike status in their roles as protectors, or as oppressors, which has made questioning their methods both risky and emotionally complex. The next chapter will explore why.