A Hunter-Gatherer's Guide to the 21st Century: Evolution and the Challenges of Modern Life

by Heather E. Heying

The differences between the sexes are found in babies, and across cultures, too—so this is not some weird WEIRD phenomenon. Given a choice, neonate girls spend more time looking at faces, while neonate boys spend more time looking at things.

What might we learn from these truths? We can learn that gender roles can be re-upped for modernity: some men will prefer hearth and home to a grueling career that is facilitated by having a spouse taking care of the domestic duties, and some women will prefer the latter. But many men and women, we argue, will prefer to be restricted to neither domain—without being slotted into preconceived roles, many people of both sexes will prefer a partner who is their equal, without being identical. We can learn from a more nuanced understanding of “gendered work” that traditionalist appeals to women not working outside of the home, or to men being dominant in economic and business matters, are regressive, without any nugget of necessity or truth. Historically, women and men have had division of labor, both in family units and in societies, but other than those tasks mandated by anatomy and physiology (gestation, lactation), there is little in the modern world that some women might not choose to do. Similarly, men are ever more welcome in traditionally female fields such as nursing and teaching, although we shouldn’t expect parity there either. Different preferences lead to different choices. Pretending that we are identical, rather than ensuring that we are equal under the law, is a fool’s game.

In every culture studied, women were more interested in mates with high earning potential than were men. Furthermore, men were more interested in potential mates who are young, and physically attractive, than were women.41 Why would this be so? Women who might get pregnant will have an easier time if that child has a father who contributes to the well-being of his child and mate. So women will be selected to prefer men with the capacity to earn. Because female fertility peaks early, and falls off far more steeply than male fertility does, men who might father children are more likely to be interested in youth and beauty in their mates—both of which can be understood to be proxies for fertility.

Certainty of paternity is far harder to come by, but important from a not-very-interesting-but-fundamental evolutionary perspective. Because fathers have never had certainty of paternity until recent technological advances have made it possible, the evolution of jealousy and mate guarding is far more prevalent in men than in women. Across cultures, men have tried to control the reproductive activities of women in such a way that they could increase their own certainty of paternity.

As women have increasingly engaged in reproductive strategy three, the short game, sex has become more mundane and easier to source. Contra the messaging of sex-positive feminists, engaging in this short game diminishes the sexual power of women. When people of both sexes are routinely seeking frivolous, no-emotional-connection sex, they are creating conditions in which everyone is behaving like men at their (second) worst. It’s not as bad as rape, obviously. But it’s not as good as strategy one, either. Society sliding toward this third reproductive strategy for both men and women is a variation on the Sucker’s Folly—the tendency of concentrated short-term benefit (sexual pleasure) not only to obscure risk and long-term cost, but also to drive acceptance even when the net analysis is negative (in reducing the chances of finding love and all that flows from it). Furthermore, women often don’t intuit that there are two distinct male strategies (aside from rape), and so are often advertising toward men engaged in strategy three, the one that looks for one-night stands, while actually angling for men interested in strategy one. Hotness is a manifestation of sexual strategy three gaining primacy. Beauty, by comparison, is a manifestation of the first sexual strategy, the one that’s in it for the long term. Hotness fades fast with reproductive potential. Beauty fades far more slowly. We are due for a major renegotiation of the deal between the sexes. We cannot go back, and must...

Just as jealousy varies by sex—men are more likely to be jealous of physical infidelity, women are more likely to be jealous of emotional infidelity45—so too do the target audiences of porn and erotica vary by sex. In general, women prefer erotica,46 which brings with it a backstory, as it were. Porn, targeting that third sexual strategy, reduces human bodies to our constituent parts, and puts a premium on extreme sexual acts as a result of economic competition for attention.

Among populations that have come of age on a steady diet of porn, women are far more likely to report being asked to engage in anal sex, strangling, and other violent “games” that are represented on-screen,47 even though few real women want these things in life.

Porn, we posit, produces what we will call...

All mammals are cared for by their mothers, and mother’s love, we argue, is the most ancient and fundamental form of love. All true love is an elaboration on this concept.

In all mammals, and in that majority of birds in which parental care is the rule, offspring are fed and protected by their parents. This leaves the young developmentally free to evolve toward helplessness—they don’t have to defend or feed themselves if a parent is there to do that job for them.

Humans are far closer to swans than to elephant seals when it comes to sexual size dimorphism, but we are no swans. Men are, on average, about 15 percent larger than females,5 and significantly stronger. This tells us that our ancestors were at least somewhat polygynous or promiscuous.

Because monogamous males select a female and forgo sexual opportunities with others, they have as much reason as females to be choosy about sex partners. Males being choosy in this way reduces their tendency toward violence. They may yet fight over access to the best females, but no longer need aspire to the acquisition and defense of “harems,” which are closely associated with aggression and physical weaponry like antlers and piercing teeth.

Monogamy also creates a system in which nearly everyone has a mate, as sex ratios tend to be one-to-one within populations, regardless of mating system. This prevents the accumulation of sexually frustrated males for whom violence may be the only path to reproduction, either through the overthrow of harem owners—as in lions and elephant seals—or through rape—as in ducks and dolphins. We will return shortly to some of the profound implications of monogamy for human societies.

Males without “certainty of paternity” are unlikely to stick around to pair-bond with a female and help raise the kids. Male birds tend to have high certainty of paternity, but male mammals are rarely certain at all. As a result, male mammals tend to abandon mates and offspring when—if they could just be confident of their paternity—selection would clearly favor their sticking around to help. Mammals have a harder time evolving stable monogamy even though it is, in most regards, the superior mating system.

All else being equal, people in monogamous cultures experience lower birth rates, and higher socioeconomic status, than those in polygynous ones. Furthermore, the age difference between spouses is smaller.13 In part, this likely reflects a move away from viewing women and girls as commodities, which strongly polygynous cultures often do.

Women may consciously want to enjoy sex without commitment, but they are wired to fall in love with the men they bed because sex, babies, and commitment are evolutionarily inextricably linked for women. Sex and orgasm trigger the release of oxytocin in females, which promotes bonding.

In the United States, a large fraction of black men have been forced into such a situation. Men who avoid these bad fates find themselves in high sexual demand and tend to play the field, leaving many black women to raise families without a committed partner. Many in the ruling class have long pretended that this pattern derives from some imagined moral failing among black people, when instead it plainly emerges from demographics and game theory that would produce the same pattern in any population faced with similar conditions.

There is, of course, plenty to say about the implications and evolution of homosexuality, in both humans and other species. While we have no room in this book for such an analysis, we will offer the short tease here that while lesbians and gay men are both homosexual in that they are attracted to individuals of the same sex, the differences between the two, in terms of both evolutionary origins and how the relationships tend to play out for those in them, are large, and consistent with the differences between women and men that we have laid out in the previous two chapters. Furthermore, both forms of homosexuality—female same-sex attracted and male same-sex attracted—are adaptations.

And this brings us back to children as the solution to the problem of human aging: Upload the useful subset of skills, memories, and wisdom into young bodies that have been wired to facilitate, augment, and amend this cognitive package as needed. It is entirely natural to want to live a long life, and to see one’s descendants well positioned for the future. Many believe that as individuals we are entitled to more, that we personally must be preserved, but this desire is in error. Such preservation would interrupt the primary mechanism by which humans innovate and keep pace with change. We reject this ancient mechanism at our peril.

Does your pet love you? Of course your pet loves you. (Qualifier: your pet can love you if it’s a mammal or one of a few clades of birds, like a parrot. If your pet is a gecko or a python or a goldfish, your pet is probably incapable of love.)

Take time to grieve in a way that feels right to you. In the middle of deepest, earliest grief, sometimes you will be joyous, and sometimes you will not be thinking about the one whom you have lost. It ebbs and flows, loses some of its power over time, but never disappears entirely. No matter what, honor your memories and your inclinations.

Spend time with the body of your loved one after they die. Those who have lost loved ones to situations from which their bodies could not be recovered often suffer from prolonged periods of grief. When we view our dead, sit with them, and talk with them, we set a foundation upon which our grief, our neural recalibration, can be moored.

Breastfeed your infants, if you can. Adults who were breastfed have better-formed palates and better-aligned teeth compared to those who were bottle-fed;20 and breast milk has in it all manner of nutrients and information that we do not understand. It may, for instance, contain cues with which the infant entrains his sleep-wake cycle. Thus, if you do breastfeed, and also pump milk to feed the baby at other times, feeding your baby milk that was pumped at the same time of day as it currently is could be helpful in getting your baby to sleep when you want him to. Put another way: beware Chesterton’s breast milk.21

Humans are not blank slates, but of all organisms on Earth, we are the blankest.4 We have the longest childhoods on Earth,5 and we arrive in the world with more plasticity than any other species—meaning that we are the least set in stone. Software, which is the interplay of experience and knowledge with capacity, is more important in humans than in any other species.

Furthermore, we quickly lose some of our ability to hear and construct the phonemes and tones of languages that are not in our environment, regardless of our particular ethnicity or lineage. Just as we are born with more neuronal potential than we use (most of our neurons die off before we become adults), we are also born with more linguistic potential than we use, and some of it is lost during childhood. We

We cannot predict ahead of time precisely what neurons we will need, or what language we will speak, so we are born with a surplus of capacity. This permits us to optimize our minds to whatever world we find ourselves born into, without the need for prior knowledge.

Spending time as children allows animals to learn about their environment. Therefore, stealing childhood from the young—by organizing and scheduling their play for them, by keeping them from risk and exploration, by controlling and sedating them with screens and algorithms and legal drugs—practically guarantees that they will arrive at the age of adulthood without being capable of actually being adults. All of these actions—almost always well intentioned—prevent the human software from refining our crude and rudimentary hardware.

Absent childhood, animals must rely more fully on hardware, and therefore be less flexible. Among migratory bird species, those that are born knowing how, when, and where to migrate—those that are migrating entirely with instructions they were born with—sometimes have wildly inefficient migration routes. These birds, born knowing how to migrate, don’t adapt easily. So when lakes dry up, forest becomes farmland, or climate change pushes breeding grounds farther north, those birds that are born knowing how to migrate keep flying by the old rules and maps. By comparison, birds with the longest childhoods, and those that migrate with their parents, tend to have the most efficient migration routes.10 Childhood facilitates the passing on of cultural information, and culture can evolve faster than genes. Childhood gives us flexibility in a changing world.11

The ways that children enforce their own views of appropriate behavior on other children may look mean to adults, but when children are actually allowed to roam freely, in groups, and engage in long periods of unstructured play, the bullies and jerks are more likely to lose power than gain it,13 and everyone learns how to both create and follow rules that work.

It is imperative that children experience discomfort in each of these realms: physical, psychological, and intellectual. Absent that, they end up full-grown but confused about what harm actually is. They end up children in the bodies of adults.

Childhood—and by extension parenting—is an interplay of love and release, of holding someone close while also giving them freedom to explore, even perhaps to leave.

For many traits, though, a particular genotype encodes information for a range of possible phenotypes,17 and interactions with the molecular, cellular, gestational, and external environment determine what phenotype will actually be produced.

WEIRD parents are not just focused on our children, we are focused on the metrics that are easily recorded and conveyed to others: the when of our child’s first smile, word, or step. Once we have such metrics in hand, we are easily confused into imagining that the when is a critical measure not just of health, but of future capacity. Once again, the easily measured thing—the calorie, the size, the date—becomes an inaccurate stand-in for a larger analysis of the health of the system. By believing in the false notion that when a benchmark is met is the salient measure of health and progress, we play into our modern fear of risk. It is risky for my child to miss a benchmark. It is risky for me not to force my child to meet arbitrary deadlines. Such parental focus can instill fear in our children, which they carry forward as an aversion to risk.

Let your children in on (almost) every conversation. Reward your children’s inquisitiveness with conversation, and do not dumb ideas down for them. Obviously, there are some things that are inappropriate at various developmental stages and ages, and what you personally decide is appropriate and when will vary by person, but in general, assume that your child is smart and can handle the content of an adult conversation. Don’t try to make them interested, just have it, demonstrate through your actions that this is what is valuable, and they will come to value it too (just like with food). Similarly, involve them in tasks that are actually useful, and engage them in those tasks in a way that enhances their understanding of the world.

School—and, obviously, parents—should teach children: Respect, not fear. To honor good rules and question bad ones. All people run into bad rules—whether in the legal system, at home, at school, or elsewhere. If you’re a parent, strive to show your children that you are 100 percent on their team—no matter the trouble they’ve bumped up against. Children should be free to ask why the parents’ rules are what they are, but also know that it is counterproductive to break the rules simply for the sake of breaking them.

Humans are evolved to be antifragile: We grow stronger with exposure to manageable risks, with the pushing of boundaries, fostering openness to serendipity and to that which we do not yet know. This is true for both bones and brains. Doing things with nonnegotiable outcomes in the physical world—skateboarding, growing vegetables, ascending a peak—provides a corrective to many wrongheaded ideas currently passing for sophisticated.

What the rat enrichment experiments suggest is that one contributor to addiction can be boredom. Or more specifically, a lack of awareness, or obfuscation, of opportunity cost. Boredom is effectively synonymous with the “opportunity cost” having gone to zero: if you believe there is nothing else enriching that you could spend your time on, then the calculation of whether or not to engage with a particular substance or action is skewed, particularly if that substance or action results in a feeling of enrichment, even a false one.

Become aware of the constant flow of information telling you what to think, how to feel, how to act. Do not let it into your mind. Do not let it steer you. Your internal reward structure needs to be independent and ungameable. That independence, in turn, should allow you to collaborate well with others who are similarly independent. Be wary of those who may well be nice, but who are captured.

if there are demonstrable differences in disease risk by birth month, why should we imagine that there are no differences in personality?

Honor or create rituals that recur—annually, seasonally, weekly, or even daily. They might be ancient and religious in origin (e.g., honoring the Sabbath or Lent—a time for both selective privation and community), astronomical (e.g., recognizing and celebrating the solstices and equinoxes), or entirely new with you and yours.

Consider engaging with psychedelics, carefully, if there is anything in you that is curious. They are now legal in some places. But consider engaging them as the powerful cognitive tools that they are, not as a form of recreation. That doesn’t mean you can’t have fun.

In 1491, the New World is estimated to have had between fifty million and one hundred million people in it, with uncountable distinct cultures and languages. Some people were living in city-states, among astronomers, craftsmen, and scribes; others as hunter-gatherers.

Wholly unaware of the other’s existence, the Maya and the Romans were at their peak at the same time, in the early part of the first millennium, and both were in obvious decline by the beginning of the second.

Keep commerce away from children, for as long as possible. Children raised to put high value on the transactional nature of being become dedicated consumers. Consumers are less observant, meditative, and deeply thoughtful than people who value creating, discovering, healing, producing, experiencing, communicating.