Human evolution has a public relations problem. That isn’t just because some people are skeptical of science in general or because creationists reject the notion of evolution. As it is often studied and taught, human evolution can be male-biased and Eurocentric, even reeking of sexism and racism.
This evolutionary tale from President Trump, with help from a ghostwriter, in “Think BIG and Kick Ass in Business and Life,” illustrates the problem:
“The women I have dated over the years could have any man they want; they are the top models and the most beautiful women in the world. I have been able to date (screw) them all because I have something that many men do not have. I don't know what it is but women have always liked it. So guys, be cocky, confident, smart, and humorous and you will be able to get all the women you want. … We may live in houses in the suburbs but our minds and emotions are still only a short step out of the jungle. In primitive times, women clung to the strongest males for protection. They did not take any chances with a nobody, low-status male who did not have the means to house them, protect them, and feed them and their offspring. High-status males displayed their prowess through their kick-ass attitudes. … They did not give a crap about what other people in the tribe thought. That kind of attitude was and still is associated with the kind of men women find attractive. It may not be politically correct to say but who cares. It is common sense and it's true — and always will be.”
This just-so story about men, women, sex and success may fit with many people’s impression of human evolution, but it contradicts the actual science.
First, simple genetic explanations don’t exist for most complex behaviors. There are no known genes for kick-ass attitudes or wanting to have sex with someone who exhibits them. Further, it’s unlikely that Trump would exist had his ancestors not given “a crap about what other people in the tribe thought.” Prosociality — cooperating with others, maintaining rich and mutually trustworthy relationships — is humanity’s bread and butter. Finally, although it’s true that we are primates descended from a long line of jungle-dwelling ancestors before they expanded into all kinds of habitats, it’s also true that evolution never stopped. Very little about us “always will be.”
Yet for all the missed beats and flat notes, it’s clear that Trump’s tale is riffing on some outdated but persistent ideas in popular science.
In every human population around the world, men are on average larger and stronger than women, as is the case in most other primate species. This is often explained by sexual selection for male dominance, that is, male vs. male competition for mates. So, in the past, bigger, dominant males fought and scared away smaller ones and had more opportunities to mate with females. As a result of their relatively greater reproductive output, the genes of these males got passed on at a relatively higher rate than the genes of the smaller guys. This process was enhanced by female preference for making babies with these bigger, stronger, dominant males.
Traditional perspectives on human evolution such as this one about men and women’s body size and behavior have long dominated the science and its popular dissemination. But it deserves scrutiny.
Presenting a human evolutionary narrative over and over again in which male competition and female preference are the explanation for big, strong males is too narrow, too simple. It reminds me of when students claim that their B in my human evolution course is keeping them off the dean’s list, but their transcript isn’t exactly straight As. There’s usually more to a story.
A more nuanced explanation for male dominance is less likely to lead anyone to conclude that patriarchy is hard-wired in our genes. Just look more carefully at nature, at the social sciences, the humanities, art, literature! Myriad biological and non-biological factors contribute to the development and persistence of the global phenomenon of how men are disproportionately powerful, and even more so if they belong to the ruling race, religion or clan.
Male baboons and chimpanzees coerce and harass females for sex and obviously male humans do, too, but that’s not evidence for genetically hard-wired, male-dominant sexual behavior at all, let alone for it being at the root of the patriarchy. Imagine someone leaping from the observation that primates eat hand-to-mouth to the assumption that it’s a genetic cause of our growing waistlines. When it comes to sex, we can inadvertently make some atrocious leaps of evolutionary logic about any species, but most of all ourselves. Not only are all primates stellar social learners of good, bad and nifty behaviors, but this overly imaginative primate can’t help but inject bias into making sense of it all. Shared behaviors of monkeys, apes and us are not excuses to be fatalistic about sexual harassment and assault by humans who have a much more complex culture in which to learn cooperative behavior and to enforce it. Yes, we’re primates, and we’re also humans.
It may be true that Trump’s version of maleness is a result of natural and sexual selection, but every other version of maleness across the globe is just as much (or just as little) a product of evolution as is his. If we ask different questions, we reveal other facets of our evolutionary history.
Primatologist Sarah Hrdy in 1981 published one of many books toward a more complex and complete human evolutionary history called “The Woman That Never Evolved.” Using the same theoretical tools that scientists had used to build the male-driven explanation for male body size and male dominance, she flipped the question. She asked why so many females in the primate world weren’t as big as males or even bigger, since female primates compete, too.
Females do not coyly wait for a champion to earn the honor of having sex with them. They do not necessarily cling to males for defense any more than males do, and often such “clinging” is just a warped description of male dominance over smaller females. Only some of the facts of nonhuman primate behavior are gathered, even fewer are published, and when they are, human bias factors into their interpretation. What we have is only part of the story.
Evolutionary theory has grown up since its conception. Based on mountains of observations of genes and traits over generations, evolutionary scientists have developed much more skepticism toward explanations that lean too dogmatically on natural or sexual selection. Scientists increasingly resist the temptation to assume that everything evolved “for” a single or specific reason, and that everything must exist because it boosted the survival and reproduction of those who passed it on. We know that perpetual mutation and the chance of passing along (or not passing along) traits occurs within complex cooperative systems with constant biological change.
The biological changes that matter most often have to do with embryological development rather than beating the competition to food, safety, or mates. We know that natural and sexual selection permit constant change, are usually very weak, and tolerate a lot of variation. This view of life is household thinking for many scientists and scholars, but it has hardly made its way out to the public. Why not?
We seem to be stuck on an old story that is less than what we deserve. Maybe it’s because some analyses trying to break the male-biased mold are dismissed as “feminism,” which is still widely assumed to be incompatible with the scientific pursuit of knowledge. Maybe it’s a thirst for American narratives where exceptional individuals are being specially “selected.” Maybe it’s because when a person’s autobiography is largely a quest to get laid, their biography for our species can’t help but echo that.
But there are billions of human experiences, all equally worthy of influencing evolutionary thinking.
Like most girls, I reached my maximum height years before my male friends did. What I have learned as a biological anthropologist suggests that physiological constraints on growth could help explain why women stop getting taller right around the time we start regular menstrual cycles, a costly metabolic process that could divert resources away from height. Pregnancy and lactation are even costlier, so women’s smaller bodies may boost but also betray their talent for metabolic marathons. There could be a similar explanation for why men do not grow even bigger than they do, as we might expect after generations of kick-ass attitudes. Furthermore, male dominance may be much more the result of their bigger bodies than the cause. Anthropologist Ruth Benedict summed it up long ago by writing, “The trouble with life isn't that there is no answer, it's that there are so many answers.”
Human evolution is for everyone, Trump included. We each take our species’ origin story personally. Evolution may as well be a gigantic Rorschach test, and that goes for the scientists, too. Some see the competition and identify with its battle cry “survival of the fittest,” while others see infinite cooperation despite constant change. Perspectives on evolution vary wildly among experts and nonexperts alike, but too few are aware of it. So let’s flood the texts, the classrooms, the campfire circles, the zeitgeist with diverse stories from diverse perspectives on the science of human evolution.
Without diverse lives contributing to the science, our evolutionary stories will remain simplistic and woefully incomplete. And when translated in the public sphere, our myopic stories are too often used to justify self-interest and the status quo, such as gender inequality and racism. Trump made this too garish to ignore any longer.
Science has a diversity problem. There was passionate debate before the March for Science about whether it should be explicitly political and whether it should include diversity and inclusion among its chief causes. Beyond the many impacts of these issues on human lives, there are also very real consequences for the knowledge that humans create. Diversifying the brains, bodies and voices of science means better science, better understanding of how the world works. Perhaps they will generate questions about human evolution that no one thought to ask.
Holly Dunsworth is an associate professor of anthropology at the University of Rhode Island.