Nature is a collaborative act. If humans are the most evolved species, it is only because we have developed the most advanced ways of working and playing together.
We’ve been conditioned to believe in the myth that evolution is about competition: the survival of the fittest. In this view, each creature struggles against all the others for scarce resources. Only the strongest ones survive to pass on their superior genes, while the weak deserve to lose and die out.
But evolution is every bit as much about cooperation as competition. Our very cells are the result of an alliance billions of years ago between mitochondria and their hosts. Individuals and species flourish by evolving ways of supporting mutual survival. A bird develops a beak which lets it feed on some part of a plant that other birds can’t reach. This introduces diversity into the population’s diet, reducing the strain on a particular food supply, and leading to more for all. What of the poor plant, you ask? The birds, much like bees, are helping the plant by spreading its seeds after eating its fruit.
Survival of the fittest is a convenient way to justify the cut-throat ethos of a competitive marketplace, political landscape, and culture. But this perspective misconstrues the theories of Darwin as well as his successors. By viewing evolution through a strictly competitive lens, we miss the bigger story of our own social development and have trouble understanding humanity as one big, interconnected team.
The most direct benefit of more neurons and connections in our brains is an increase in the size of the social networks we can form.
The most successful of biology’s creatures coexist in mutually beneficial ecosystems. It’s hard for us to recognize such widespread cooperation. We tend to look at life forms as isolated from one another: a tree is a tree and a cow is a cow. But a tree is not a singular tree at all; it is the tip of a forest. Pull back far enough to see the whole, and one tree’s struggle for survival merges with the more relevant story of its role in sustaining the larger system.
We also tend to miss nature’s interconnections because they happen subtly, beneath the surface. We can’t readily see or hear the way trees communicate. For instance, there’s an invisible landscape of mushrooms and other fungi connecting the root systems of trees in a healthy forest. The underground network allows the trees to interact with one another and even exchange resources. In the summer, shorter evergreens are shaded by the canopies of taller trees. Incapable of reaching the light and photosynthesizing, they call through the fungus for the sun-drenched nutrients they need. The taller trees have plenty to spare, and send it to their shaded peers. The taller trees lose their leaves in the winter and themselves become incapable of photosynthesizing. At that point, the evergreens, now exposed to the sun, send their extra nutrients to their leafless community members. For their part, the underground fungi charge a small service fee, taking the nutrients they need in return for facilitating the exchange.
So the story we are taught in school about how trees of the forest compete to reach the sunlight isn’t really true. They collaborate to reach the sunlight, by varying their strategies and sharing the fruits of their labor.
Trees protect one another as well. When the leaves of acacia trees come in contact with the saliva of a giraffe, they release a warning chemical into the air, triggering nearby acacias to release repellents specific to giraffes. Evolution has raised them to behave as if they were part of the same, self-preserving being.
Animals cooperate as well. Their mutually beneficial behaviors are not an exception to natural selection, but the rule.
Darwin observed how wild cattle could tolerate only a brief separation from their herd, and slavishly followed their leaders. “Individualists” who challenged the leader’s authority or wandered away from the group were picked off by hungry lions. Darwin generalized that social bonding was a “product of selection.” In other words, teamwork was a better strategy for everyone’s survival than competition.
Darwin saw what he believed were the origins of human moral capabilities in the cooperative behavior of animals. He marveled at how species from pelicans to wolves have learned to hunt in groups and share the bounty, and how baboons expose insect nests by cooperating to lift heavy rocks.
Even when they are competing, many animals employ social strategies to avoid life-threatening conflicts over food or territory. Like breakdancers challenging one another in a ritualized battle, the combatants assume threatening poses or inflate their chests. They calculate their relative probability of winning an all-out conflict and then choose a winner without actually fighting.
The virtual combat benefits not just the one who would be killed, but also the victor, who could still be injured. The loser is free to go look for something else to eat, rather than wasting time or losing limbs in a futile fight.
Evolution may have less to do with rising above one’s peers than learning to get along with more of them.
We used to believe that human beings developed larger brains than chimpanzees in order to do better spatial mapping of our environment or to make more advanced tools and weapons. From a simplistic survival-of-the-fittest perspective, this makes sense. Primates with better tools and mental maps would hunt and fight better, too. But it turns out there are only slight genetic variations between hominids and chimpanzees, and they relate almost exclusively to the number of neurons that our brains are allowed to make. It’s not a qualitative difference but a quantitative one. The most direct benefit of more neurons and connections in our brains is an increase in the size of the social networks we can form. Complicated brains make for more complex societies.
Threats to our relationships are processed by the same part of the brain that processes physical pain.
Think of it this way: a quarterback, point guard, or midfielder, no matter their skills, is only as valuable as their ability to coordinate with the other players; a great athlete is one who can predict the movements of the most players at the same time. Similarly, developing primates were held back less by their size or skills than by their social intelligence. Bigger groups of primates survived better, but required an increase in their ability to remember everyone, manage relationships, and coordinate activities. Developing bigger brains allowed human beings to maintain a whopping 150 stable relationships at a time.
The more advanced the primate, the bigger its social groups. That’s the easiest and most accurate way to understand evolution’s trajectory, and the relationship of humans to it. Even if we don’t agree that social organization is evolution’s master plan, we must accept that it is — at the very least — a large part of what makes humans human.
Human social cohesion is supported by subtle biological processes and feedback mechanisms. Like trees that communicate through their root systems, human beings have developed elaborate mechanisms to connect and share with one another.
Our nervous systems learned to treat our social connections as existentially important — life or death. Threats to our relationships are processed by the same part of the brain that processes physical pain. Social losses, such as the death of a loved one, divorce, or expulsion from a social group, are experienced as acutely as a broken leg.
Managing social relationships also required humans to develop what anthropologists call a “theory of mind” — the ability to understand and identify with the thinking and motivations of other people. From an evolutionary perspective, the concept of self came after our ability to evaluate and remember the intentions and tactics of others. Unlike the relatively recent cultural changes that encouraged ideas of personal identity or achievement, our social adaptations occurred over hundreds of thousands of years of biological evolution. Enduring social bonds increase a group’s ability to work together, as well as its chances for procreation. Our eyes, brains, skin, and breathing are all optimized to enhance our connection to other people.
Prosocial behaviors such as simple imitation — what’s known as mimesis — make people feel more accepted and included, which sustains a group’s cohesion over time. In one experiment, people who were subtly imitated by a group produced less stress hormone than those who were not imitated. Our bodies are adapted to seek and enjoy being mimicked. When human beings are engaged in mimesis, they learn from one another and advance their community’s skill set.
The physical cues we use to establish rapport are preverbal. We used them to bond before we ever learned to speak — both as babies and as early humans many millennia ago. We flash our eyebrows when we want someone to pay attention to us. We pace someone else’s breathing when we want them to know we empathize. The pupils of our eyes dilate when we feel open to what another person is offering. In turn, when we see someone breathing with us, their eyes opening to accept us, their head subtly nodding, we feel we are being understood and accepted. Our mirror neurons activate, releasing oxytocin — the bonding hormone — into our bloodstream.
Human beings connect so easily, it’s as if we share the same brains. Limbic consonance, as it’s called, is our ability to attune to one another’s emotional states. The brain states of mothers and their babies mirror each other; you can see this in an MRI scan. Limbic consonance is the little-known process through which the mood of a room changes when a happy or nervous person walks in, or the way a person listening to a story acquires the same brain state as the storyteller. Multiple nervous systems sync and respond together, as if they were one thing. We long for such consonance, as well as the happy hormones and neural regulation that come with it. It’s why our kids want to sleep with us — their nervous systems learn how to sleep and wake by mirroring ours. It’s why television comedies have laugh tracks — so that we are coaxed to imitate the laughter of an audience of peers watching along. We naturally try to resonate with the brain state of the crowd.
These painstakingly evolved, real-world physical and chemical processes are what enable and reinforce our social connection and coherence, and form the foundations for the societies that we eventually built.
Thanks to organic social mechanisms, humans became capable of pair bonding, food sharing, and even collective childcare. Our survivability increased as we learned how to orchestrate simple divisions of labor, and trusted one another enough to carry them out.
The more spectacular achievement was not the division of labor but the development of group sharing. This distinguished true humans from other hominids: we waited to eat until we got the bounty back home. Humans are defined not by our superior hunting ability so much as by our capacity to communicate, trust, and share.
Biologists and economists alike have long rejected social or moral justifications for this sort of behavior. They chalk it up instead to what they call “reciprocal altruism.” One person does a nice thing for another person in the hope of getting something back in the future. You take a risk to rescue someone else’s child from a dangerous predator because you trust the other parent to do the same for your kid. In this view, people aren’t so nice at all; they’re just acting on their own behalf in a more complicated way.
But contemporary research strongly supports more generous motives in altruism, which have nothing to do with self-interest. Early humans had a strong disposition to cooperate with one another, at great personal cost, even when there could be no expectation of payback in the future. Members of a group who violated the norms of cooperation were punished. Solidarity and community were prized in their own right.
Evolution’s crowning achievement, in this respect, was the emergence of spoken language. It was a dangerous adaptation that involved crossing the airway with the foodway, making us vulnerable to choking. But it also gave us the ability to modify the sounds that came from our vocal folds and make the variety of mouth noises required for language.
While language may have been driven by the need for larger, more complicated social structures, think of the immense collaborative act that developing a language required from its speakers. That multigenerational exercise alone would change the fabric of society and its faith in a cooperative enterprise.
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