Usually when someone starts talking about how our inner cavemen chafes against our modern lifestyles, it’s a man justifying his cheating on his wife: “I am not built for monogamy — I am programmed to spread my seed!” Our sex lives are not the only part of us that goes against “nature.” From our diets to our urban surroundings to our parenting, modern life occasionally goes so against our evolutionary impulses that we become sick. With depression and obesity on the rise, and our recent exiting from the most violent century in the history of mankind, the warning signs that we are living wrong keep showing up.
When we talk about human evolution, it’s helpful to remember that we are a mere speck on the Earth. The Earth is estimated to be around 4.5 billion years old. The first lifeform, 2.7 billion years old. Primates only showed up 65 million years ago, followed by hominids 6.5 million years ago. Our own species has existed only for 200,000 years. We shifted from hunter-gatherer to agrarian society approximately 12,000 years ago. Humans carry around many impulses and instincts that do not serve us well in our crowded cities, where we pick up bags of Doritos and frozen pizzas on our way home from eight hours hunched over a keyboard, only to collapse on the couch drinking a few beers alone in front of a TV airing Two and a Half Men.
Oxford archaeology and anthropology lecturer Timothy Clack opens Ancestral Roots: Modern Living and Human Evolution with the question, “Is it just me or is everything shit?”, which should tell you a bit about where he stands on modern life. He looks at society today and sees such a landfill of despair, violence, and fat that he yearns for the hunter-gatherer phase. Clack focuses on some of the major problems with modern life and looks for clues in our evolutionary history to explain why, for example, we crave foods high in fat and how we can alter our behavior to better suit our nature. Not that he’s hopeful. He writes in the prologue, “As the psychologist Oliver James recently commented, our focus should be ‘why we are so fucked up, not with dangling a false promise of the possibility of happiness.’” In other words, get ready for the “glass half empty” version of human evolution.
There are many reasons for Clack’s pessimism. We somehow seem to be increasingly maladjusted to our surroundings, and that is expressed in our warmongering, religious extremism, environmental degradation, increased rates of depression and anxiety, and the shortening of our lifespans due to the Western diet. He writes, “We have lost many things: a sense of belonging, communal spirit, religious and spiritual experiences, and feelings of purpose and direction.” But, perhaps if we understand why these things make us sick and miserable, we can make some changes in our lives and societies to align them better with our nature.
Take, for example, modern city life. We are an increasingly urban species, and by 2020 approximately 60 percent of the human population will live in cities. We’re not meant to live in such close quarters, however. If we commute to our jobs by public transit, our “body buffer zone” is violated at least twice a day. Having someone rub up against you on the subway isn’t just irritating — it increases our propensity for violence and the potential for transmission of airborne diseases. If you drive into work, the same violation of your personal space causes road rage. The noise of the city can cause chronic anxiety, high blood pressure, and hearing loss. Light pollution disrupts our sleep cycles. Cities are always hotter than the surrounding areas, and every degree the temperature goes up, the higher the rates of assault and homicide.
We’re also maladjusted to the free market system, to living with such polluted air and water, to being so far removed from nature, and to living in unjust societies. There are a few bright spots, however. Our loosening of religion-based morals means a loosening of puritanical views of sex, and sex is quite healthy. Clack recommends it as a depression-lifting activity, since the rush of endorphins and oxytocin is good for the sad and lonely (“If the sex is good,” he should qualify). Also, the “flattening” of the world means it is more and more difficult to dehumanize other people. The more carnage we see in Iraq, the more distasteful the war becomes.
Occasionally Clack’s own prejudices get in the way. He makes a strong argument for having one person in the modern family stay home, take care of the kids, and cook dinner. He makes sure to say it does not have to be the wife, although considering that there is still a significant wage gap between men and women, it’s easy to guess who’ll be donning the apron. But for all of Clack’s examination of every aspect of human life, he does not look at the evolutionary affect on the stay-at-home mother. Lately there has been much talk in the New York Times and Parenting magazine about the overwhelming anger that wives and mothers feel towards their husbands for not doing a fair share of parenting and housework. Modern parenting is a significant part of our lives to which we are apparently maladjusted. If Clack is silent on the subject, surely someone else has the reason.
In her 2000 book Mother Nature, Sarah Blaffer Hrdy examined the maternal instinct, fathering, and the evolutionary explanation for babies’ ridiculous cuteness and fatness. (In short, “Look, I’m adorable and healthy! Do not throw me in the fire or leave me in the forest!”) In her new book Mothers and Others: The Evolutionary Origins of Mutual Understanding, she starts with the question, Why are humans able to sit in the coach section of an airplane for hours and hours without fatalities? No other primates would be so polite and considerate, especially when someone rolls carry-on luggage across their toes. “What if I were traveling with a planeload of chimpanzees? Any one of us would be lucky to disembark with all ten fingers and toes still attached… Even among the famously peaceful bonobos… veterinarians sometimes have to be called in following altercations to stitch back on a scrotum or penis,” Hrdy writes. What she found is that our unique mothering instinct, quite different from gorillas and chimpanzees, meant that the children most likely to survive were those who could relate to and solicit help from others. We evolved to be wired for empathy for, consideration of, and intuition into how others are feeling.
Most other primate mothers guard their offspring jealously. They carry their children at all times, even if the babies are too weak or deformed to maintain a grip on their mother’s fur. Baby chimpanzees are raised by their mothers alone until they are able to fend for themselves. They grow into selfish, violent adult chimpanzees who, during experiments, are quite content to watch other chimpanzees go hungry, even if they only need to pull on a rope to feed their neighbor.
Humans, however, are built to be raised by many different people. Human babies do best when they have at least three secure “alloparents,” or, as the title says, “mothers and others.” The alloparents could be the mother, grandmother, and father, or, as a recent article by Emily Bazelon about a group of single mothers who help raise each other’s children suggests, the mother and a bunch of her friends. If a mother feels unsupported, whether she’s a !Kung widow or a 15-year-old girl giving birth in the high school bathroom, she might abandon her baby altogether. Some simply choose not to have children at all — look at the low birth rates among educated career women. The nuclear family is a very recent construct, and Clack perhaps should have added it to the list of things we are not adapted for.
Babies who were able to convince people other than their mothers to take care of them and feed them were more likely to survive. They were also able to guess a person’s emotional state and respond to it. Hrdy writes, “[W]hat the… studies actually show is not that having a responsive mother does not matter (of course it does) but that infants nurtured by multiple caretakers grow up not only feeling secure but with better-developed and more enhanced capacities to view the world from multiple perspectives.” Babies at a very young age are eager to share or to comfort someone who is sad. Without that empathy, we would have wiped each other out long ago, becoming just another extinct species on the primate family tree.
Clack’s pessimism is occasionally hard to take. At one point he seems to write off modern civilization entirely: “It seems difficult to disagree with Jared Diamond when he claims that agriculture was the worst blunder in human history.” But it is perhaps the humanity whose roots Hrdy chronicles that will allow our species to come together and move past this troubled time in our evolution. • 11 February 2009