Wired for Culture: Origins of the Human Social Mind

by Mark Pagel

  In nearly every other respect for which the great English philosopher John Locke proposed his doctrine of tabula rasa, the human brain has been shown to come into the world prepared, and not at all a blank slate. We are primed to learn language, to comprehend shapes and movement, to expect causation, to manipulate numerical quantities, to be afraid of heights, to mimic others, and to favor our relatives. But we are not primed to acquire any particular culture. The one we do inherit is an arbitrary story, an accident of birth, but it is one to which we show a surprising and sometimes alarming devotion. People will risk their health and well-being, their chances to have children, or even their lives for their culture. People will treat others well or badly merely as an accident of their cultural inheritance. If there is a humbling lesson of culture, it is that we do these things even though each of us might have been someone else, with a different internal voice, likes and dislikes, and allegiances. If there is a comparison, it is to ducklings whose parents have been lost and when they hatch from their shells adopt as their parent the first animal that wanders past—even a human. Animal ethologists call this imprinting; it is difficult to escape the feeling that we seem to imprint on our cultures, and in a way that is hard to shake off.

  Genes are carefully shepherded into our bodies inside small vehicles known as gametes—sperm from fathers and eggs from mothers—which are designed to see to it that a body is made that carries a collection of its parents’ genes. Part of the imprint of culture is to get us later in life to act as its shepherds. Each of us who has children will have shepherded pieces of our culture into them, some of it from mothers, some of it from fathers, ensuring that they were French, Korean, English, Melanesian, or American, Italian, Russian, or Chinese, and that they were religious or atheist, but also that they spoke a particular language and held certain beliefs about their nation and the rest of the world. We should be aware that it is at least a curious, and surely a compelling, feature of our species that a child born into the world as nothing more than a “blank” human being might be labeled as a Christian or a Hindu, Jewish, Buddhist, Muslim, or Confucian, and that this label—or some other its culture provides—can influence the course of this child’s life, as if it were a trait inherited on some gene. There are places all over the world where a child born into one of these religions might peer across a fence at children from another whose parents are sworn enemies of its own, and only then because their parents labelled them.

  The reason for this shepherding is clear. Human culture has been a development of revolutionary social and genetic effect, easily the most potent trait the world has ever known for converting new lands and resources into more humans. Our genes’ gamble at handing over control to the new sphere of evolving ideas paid off handsomely. Culture became our species’ strategy for survival, a biological strategy, not just some bit of fun and amusement on the side, and it would trump all the wonderful wings and feathers, shells, claws, poisons, acts of camouflage or deception, odors, feats of running speed, long necks or beaks, powerful jaws, and spectacular colors and displays of the rest of the animal kingdom. It didn’t have to be this way. Our newly liberated minds might have chosen aesthetic reverie, feckless indolence, jumping off cliffs, debilitating drug use, or mindless warfare. But, for the most part, we didn’t. We seem to have followed our ancient genetic instincts for survival, and culture has been remarkably able to oblige.

  The question is often asked, What makes us human? Quite apart from its interest to anthropologists and other scholars, it is a question that invades nearly every aspect of our lives, our psychology and behavior. Who are we, and why are we the way we are, so utterly different from other animals? What makes us kind and forgiving, generous and friendly, but also wicked, murderous, and vengeful? Why do we have morality? The usual answers to these questions are that we are made human by virtue of possessing consciousness, or that we have this or that gene, an opposable thumb, or an upright posture and bipedal gait, that we learned to control fire, or that we have empathy, language, or our extraordinary intelligence. For others it is the belief we are made in God’s image and in possession of a soul. And it is true, these traits and beliefs set our species apart. But the argument of this book is that these usual answers are the wrong way around. They are the wrong way around because they fail to recognize that it is only because of culture that we have many of these traits. Here is something we will have to get used to: all of us carry around in our minds something akin to a software “operating system” installed without our consent by our parents and others in our societies. It defines who we are and is our internal voice. It frames our social and cultural identities, and fundamentally influences the course of our lives. No other species has such a system. Only when we understand this, and understand how the traits we acquired in response to this new way of life serve our interests, can we begin to grasp what it means to be human.

  And here is why. Evolutionary biology teaches us that in a competitive world, if we know something about the environment an animal lives in, we can make some predictions about what it will be like. If an animal lived its life in trees or flying in the air, hunting for insects or swimming in the water, we could expect it to have acquired certain characteristics to promote its survival and well-being—long arms to swing in trees, wings for flight, an acute nose or hearing to detect insects, or a streamlined shape for swimming. Most animals are adapted to a physical environment such as one of these, and are confined to areas of the Earth where that environment is found. But for the last 160,000 to 200,000 years, humans have roamed the Earth conquering its many environments, chauffeured wherever we travelled by the inventive and cooperative tribal societies that are their cultures. And so, we are entitled to expect that, instead of adapting to the demands of any one physical environment, our genes have evolved to use the new social environment of human society to further their survival and reproduction. These are the adaptations that have wired our minds and bodies for culture.

  It is a subject that touches the most fundamental aspects of our lives. We will see in the chapters of this book that our responses to culture have produced some of our best and our worst tendencies, creating a species brimming with contradictions. Our possession of culture is responsible for our art, music, and religion, our unmatched acts of charity, empathy, and cooperation, our sense of justice, fairness, altruism, and even self-sacrifice; but also for our undeniable self-interest, our tendency to favor people from our own ethnic or racial groups, wariness of strangers, xenophobia, and predilections to war. But it goes further than this. The nature of our culture will tell us why we alone as a species have language, why it is that we alone can show kindness to strangers, and even to other animals, but also why we can be callous and murderous. It is why we are the only species with morality, but also why we apply it capriciously to suit our needs. Culture equips us with envy, jealousy, and spite, indignation and contempt, but also with friendship, forgiveness and affection, and a conscience. It is why we, and probably we alone, have consciousness, and yet why our conscious mind is often divided between reason and passion, unsure or even in conflict with itself over how to behave. It is why we differ from each other, why we differ so from the other apes despite sharing so many of their genes, why we are shrewd and deceptive, and even why we deceive ourselves. We will see that our cultures can even get us to kill our own children—so-called honor killings—and at the same time can get us to behave so selflessly that we would have to travel all the way to bees in a hive or to the cells in our body to see anything else like it in nature.

  True, it would be wrong to suggest we are the only species with culture; it is just that only in humans has the handover been so great and the occupation of our minds so complete. New Zealand’s chaffinches, a songbird carried to those islands by homesick Europeans, learn their songs from their parents and thereby produce a surprising range of local dialects. Some chimpanzee troops have cultural traditions in the styles of tools they use to fish insects from the ground, or in
the stones they use to crack nuts. Some meerkat colonies living side by side have persistent but arbitrary differences in the times they get up in the morning. There are idiosyncratic hunting styles among some dolphin pods and variety among the songs of some whales. In another dolphin species, females wear decorative sponges on their noses that they have gathered up from the seabed, and some groups of orang-utans make leaf-bundle “dolls.” Japanese macaques produce a wonderfully humanlike potato-washing behavior beloved of television documentaries. These cultural achievements are delightful, often entertaining, and sometimes even unexpected. But they bear about as much resemblance to human culture as a gorilla beating its chest or a chimpanzee drumming on a log does to a Bach cantata, scarcely deserving to be compared to the varieties, contrivances, complexities, and intricacies of human science, technologies, language, art, music, and literature.

  Still, is the 160,000 to 200,000 years we have been around long enough for traits to have evolved in response to living in the social environment of our cultures? Has there been time enough to become wired for culture? The simple way to answer this question is to look around you. For instance, sometime around 25,000 years ago, people began living above 12,000 feet in the high Tibetan plateau, and they acquired physiological adaptations that allow them to cope with the reduced oxygen at these altitudes. One of these was so advantageous that it might have spread to 90 percent of all Tibetans in just four thousand years. The Dinka tribespeople of Sudan are tall and slim and have unusually dark skin. The Inuit people of northern North America are shorter, of stocky build, and have lighter skin. The Dinkas’ spaghetti-like body shape gives them a large surface area for shedding heat, while the Inuits’ more spheroid shape reduces their surface area to conserve it. The Dinkas’ dark skin protects them from the sun, but the melanin needed to produce it isn’t needed in the Arctic, so the Inuit make less of it.

  These are all genetic adaptations acquired, in the case of the Tibetans and the Inuits, since our species walked out of Africa: a Dinka raised in the Arctic will not look like an Inuit, and vice versa, and the Tibetan capacity to live with reduced oxygen levels doesn’t evolve at low altitudes. If this kind of rewiring of our genes and physiology can take place over such short periods of time, this tells us that other features of our nature, including our psychology and social behaviors, have had plenty of time to evolve since we acquired culture.

  Even so, many people hold the view that humans fall outside the grip of Darwinian evolution by natural selection. We are intelligent beyond comparison to other animals, we use language creatively, we have art, music, dance, and religion, and, above all, a free will. But we must be careful. The standard philosophical objection to free will is that we aren’t as free to do what we “want” as we would like to think we are, because our current “wants” will always be influenced by our previous wants. And these previous wants form a chain leading all the way back to our birth and early upbringing when we were unable to make free choices. The first of these events over which we had little control might have been the accident of being born into a particular culture.

  And to an evolutionist free will isn’t even all it’s cracked up to be anyway: good judgment should trump free will in most circumstances. Throughout our evolutionary history those of us who behaved in ways that promoted our survival and reproduction, rather than merely doing what we “wanted” to do, will have left the most descendants—descendants who will have inherited these same tendencies. If even just one of your ancestors had decided to give up having children for his or her art, the consequences for you would be no different than had that ancestor been killed—you would not be here today reading this book. Indeed, it is an underappreciated fact of biology that throughout history the overwhelming majority of individuals ever born, hatched, or budded off died long before adulthood. So the world is populated today by a select group of survivors whose ancestors had the dispositions and the wherewithal to survive and reproduce, and this alone tells us there is no particular reason to believe that free will per se has been positively favored throughout our evolution. Survival is a rare thing, far too valuable to be entrusted to what could be a capricious free will.

  Many people believe that to allow natural selection a role in defining who we are consigns us to having a selfish agenda, one in which our genes single-mindedly promote their existence. Our genes do that, but it is a misunderstanding of evolution to think that natural selection always favors a nasty and ruthless nature. It is far more creative than that, and nowhere more it seems than in our species. In fact, if the history of biological evolution teaches us anything, it is that natural selection can often achieve the most for its genes by building cooperation among actors or even among genes that avoids debilitating conflict, returning greater gains than could be achieved by competition or a solitary existence. Among the triumphs of modern evolutionary biology is the demonstration that many of the outlines of culture and of our behaviors can be explained as strategies for promoting our survival and reproduction. The influential evolutionary theorist William Hamilton anticipated this some years ago, saying:

  to come to our notice cultures, too, have to survive and will hardly do so when by their nature they undermine the viability of the bearers. Thus we would expect the genetic system to have various inbuilt safeguards and to provide not a blank sheet for individual cultural development but a sheet at least lightly scrawled with certain tentative outlines… .

  It is those “tentative outlines” we seek to understand.

  THE REST OF THIS BOOK

  THE REST OF this book is about how our cultures came to occupy our minds, what they demanded of us, how those demands have been met, and whether our cultural nature provides useful solutions for living in a modern world. For many people, I think one of the most distinctive and salient features of life in human societies is the sense of belonging to a particular cultural group to which they often feel a surprising attachment and allegiance, one that can even extend in some circumstances to giving up their lives for it. So finely tuned is this tendency in us that even within our societies the cultural subdivisions can acquire a bewildering degree of complexity, as people from different regions detect minute differences in accents, preferences for food, styles of dress, religious beliefs, and manners. To outsiders, these differences may be barely, if at all, detectable. But it is a complexity that seems entirely natural to someone from one of those societies, and the differences that are so small to an outsider can seem large indeed from the inside.

  In the Preface I described a tendency throughout our history to form into small tribal societies. Some will cavil at this term, thinking it carries bigoted or prejudicial overtones, but I use it far more simply to capture that sense of a group of people, somehow organized around an identity. Even if no one can agree precisely what that identity is at any given moment and who has it or not, most people have a sense of which group they belong to, and just as importantly who doesn’t. Our dispositions to form into these groups is a phenomenon that has held throughout our evolutionary history and its effects linger in our behaviors and psychology today. We will see them over and over in this book and so we want to try to understand why we have this particular nature.

  I want to call these tribal groups cultural survival vehicles. This might seem a cumbersome term, but it is one I have found useful in trying to understand our species. Indeed, it proves so central to understanding what makes us human that it could have been the title of this book. The zoologist Richard Dawkins in The Extended Phenotype coined the term vehicles to describe structures that carry replicators. An example of a vehicle is your body, or the body of a cat or a dog. A replicator, on the other hand, is something that can make copies of itself, such as a gene. Putting these two ideas together, we can see that replicators (think of genes) exert their effects on the external world, and thereby influence the likelihood that they will survive, through the vehicles (think of your body) they build. The distinction between replicators and vehicles is importan
t because it reminds us that an animal’s body is merely a temporary structure built by its genes to promote their survival and reproduction. It can be difficult to shake the habit of thinking we are the main players in evolution rather than our genes, but your body is not replicated in your offspring; rather, your genes are, and then again in theirs.

  When I use the term cultural survival vehicle, it is to capture the idea that our species evolved to build, in the form of their societies, tribes, or cultures, a second body or vehicle to go along with the vehicle that is their physical body. Like our physical bodies, this cultural body wraps us in a protective layer, not of muscles and skin but of knowledge and technologies, and as we will see in the later chapters, it gives us our language, cooperation, and a shared identity. We are the actors that produce this vehicle, behaving almost like individual genes clamoring inside it to exert our effects on the outside world, and influencing our likelihood of surviving. Our nature is wrapped up in the strategies we evolved and now deploy to make the cultural survival vehicle work for us. It doesn’t matter that it is a shifting and fluid vehicle whose members might come and go, or that we cannot draw clear boundaries around it as a thick layer of hide or skin does. The same could be said of an ant’s nest, a lion’s pride, a troop of monkeys, or even a herd of wildebeest, and no one doubts that they are also vehicles to promote the survival and reproduction of their inhabitants.

  Still, there is a fundamental evolutionary difference between our cultures as survival vehicles and our physical bodies, and it is a difference that will make all the difference. Our genes share a common route into the future, all of them living or dying with their particular body, and this has enforced a degree of agreement among them. So complete is that agreement, most of the time our genes work together seamlessly to build our bodies, not bickering or wishing to go off in different directions. Our societal vehicles are different. Like our physical bodies they have been fundamental to our success, and this is a point that is difficult to overemphasize. Even so, we as inhabitants of these vehicles do not all share a common route into the future. Each of us, unlike our individual genes, is free to reproduce on our own. The essential balancing act of human societies is that they will normally work best when everyone pulls together, but at any given moment what is best for you might differ from that which is best for your group. Our psychology is the outcome of this balancing act. It is the set of temperaments geared toward using our cultural vehicles to promote our individual survival in a world full of others like ourselves.