Why Religion Is Like Fast Food
We are risen apes, not fallen angels — and we now have the evidence to prove it. Our vanity might make it difficult to accept, and those who believe in divine creation find the whole concept outrageous. The mere contemplation that humanity could have developed from the “lower” animals has caused many to reject evolution outright, from the moment Charles Darwin promulgated his theory. But the evidence overwhelmingly shows that we evolved along with all other living things from the primordial ooze, where life on Earth really began.
Along the east side of the African continent, the Great Rift Valley runs from Ethiopia to Mozambique. Think of this valley as the birth canal of the human species, the true Garden of Eden. This is where our particular species began its unique evolutionary trail.
We did not descend from apes. From a purely scientific viewpoint, we are apes. We share 98.6 percent of our DNA with chimpanzees. We also share with them a common ancestor that lived some five to seven million years ago. From that common ancestor, the human line diverged and developed along many different paths, like the varied branches of a bush. Eventually all but one, the one from which you and I evolved, died out.
We are the last surviving example of a specific African ape, the hominid. As evolutionarily recently as 50,000 years ago there may have been four species of closely related but distinct hominids sharing the planet with us. We alone among the hominids survive.
We have now met many of our ancestors. We possess fossils of Ardipithecus, probably one of the closest species to the distant ancestor we share with chimps. They seem to have been a pair-bonded species with low levels of aggression.
The Australopithecus, meaning the southern ape of Africa, is best known through its most famous fossil, Lucy, found in Ethiopia fifty years ago. Fossils of Paranthropus (meaning “beside human”) found in southern Africa in 1938 and 1948 show it to have had a brain about 40 percent the size of ours; it likely died out because it could not adapt to changes in environment and diet.
In 2008, a nine-year-old boy, the son of a paleontologist, discovered the skull of a considerably older nine-year-old boy in Africa. This skull, also of a hominid since named Australopithicus sediba, may provide further links between the australopithecines and us.
Those species, along with our earliest hominid ancestors, coexisted in Africa for about two million years, surviving mind-bendingly longer than we have so far.
Our group, Homo, shows up in the fossil record about two million years ago and includes Homo habilis, Homo erectus, and Homo heidelbergensis. Homo erectus made it out of Africa, probably without language, more than a million years ago, migrating as far as the Caucasus Mountains, China, and Indonesia.
It appears that some members of Homo heidelbergensis gave rise to the Neanderthals after migrating to Europe, and recent DNA sequencing data suggests that there was some hybridizing between our Homo sapiens ancestors and Neanderthals. Those Homo heidelbergensis who remained in Africa ultimately gave rise to early, anatomically modern Homo sapiens.
The earliest recognized fossils of Homo sapiens occur back to nearly 200,000 years ago. There is evidence of symbolic abilities, such as pigments potentially used in coloring, and also evidence of long-distance exchanges and trade between groups, which required a sophisticated means of symbolic communication. It seems likely that the oldest known members of our species probably had the most significant species-specific cognitive, social, and behavioral feature—the ability for language.
You and I, modern Homo sapiens with our ability for language, began to leave Africa 60,000 years ago, a blink of the eye in evolutionary time.
Put aside our ethnic, racial, nationalistic, and religious differences. Underneath our skins we are all Africans, the sons and daughters of a small group of hunter-gatherers who arose in Africa, outsurvived all others, and conquered the world.
What is even more amazing is that a severe climate variation between 70,000 and 100,000 years ago apparently reduced our population to perhaps as few as six hundred breeding individuals. That is what modern genetics now tells us. That means that every one of the seven billion people on this planet is a descendant of that small group of hunter-gatherers who lived in Africa and survived the harsh climate change.
Why us? How and why did we survive? Comparing Australopithecus, Homo erectus, and modern human skulls shows a gradual transformation in the area above the eyes. The forehead loses its steep slope and becomes rounded. A brain size of 400 to 500 cubic centimeters in Australopithecus doubles for Homo erectus and almost triples by the time of modern Homo sapiens. That change is particularly notable in the frontal lobe regions. These are the areas of our brain that contain the complex machinery, the evolved adaptations that enable us to negotiate our social worlds.
So what drove the evolution of these big brains of ours? We did. Or, more specifically, others of our species did, because we needed to work together to survive. Physical survival required social survival; we developed “groupishness.”
If you arbitrarily divide a room full of people into two groups for a game, they will invariably begin to identify with the group to which they’ve been assigned. They will consider those in their group as “in” and those in the other as “out.” There likely will be strong competition between the two groups, even if the people in them were strangers to each other when the game began. The strangers have become teammates. Hasn’t that ever struck you as odd? Probably not, because it is quite literally natural. You most likely would do the same thing. This “groupishness” is hardwired and helped our ancestors survive the worlds in which they evolved.
The crucible of small, tightly knit bands of kin sculpted us into the people we are today. This is not ancient history. As recently as five hundred years ago, two-thirds of the world’s population still lived in small hunter-gatherer tribes, the kind of social environment that shaped us and to which we are adapted. In many ways we are still quite tribal in our psychology. But then we are still very young.
So, you ask, what does this have to do with religion?
Everything.
Religion utilizes and piggybacks onto everyday social thought processes, adaptive psychological mechanisms that evolved to help us negotiate our relationships with other people, to detect agency and intent, and to generate a sense of safety. These mechanisms — which include the attachment system, the mind-body split, decoupled cognition, the hyperactive agency detection device, among many others — were forged in the not-so-distant world of our African homeland. They are why we survived.
While not an adaptation in its own right, religious belief is a by-product of those psychological mechanisms that allowed us to imagine other people and other social worlds, abilities crucial to human survival. Because religion only slightly alters those adaptations, it can be equally powerful.
Let’s look at the workings of adaptive by-products another way: do you like fast food—say, a big, juicy burger with cheese, a large side of crisp, salted fries, and an icy cola or shake? Most people like some kind of fast food, at times even crave it. If fast food doesn’t tempt you, maybe you occasionally crave a succulent prime rib. Or ice cream. You may avoid them for dietary or health reasons, but odds are that you at least occasionally break down and buy such meals, even against your better judgment.
Why does this matter? If you understand the psychology of craving fast food, a savory slice of prime rib, or a decadent chocolate sundae, you can fully comprehend the psychology of religion.
We evolved in harsh, dangerous environments. We evolved cravings for foods that were rare and crucial to our physical well-being. Nobody craves Brussels sprouts. Certain types of greens and tubers were an available source of food in the ancient world. But we all crave fat, and we all crave sweets.
The original fat was game meat, an invaluable source of concentrated protein and calories. The original sweets were ripe fruit, important sources of calories, nutrients, and vitamin C. Plentiful food was nonexistent. Starvation was always right around the corner.
Craving is an adaptation. It solves the problem of securing crucial but rare life-sustaining foods. When our ancestors experienced cravings, they sought those foods out, and because of that survived and reproduced better than those who did not inherit this particular adaptation, and thus did not crave the foods they needed.
And once they found those foods, whenever they could, our ancestors ate more than they needed at that moment. In the world in which we evolved, they couldn’t expect to find that food again tomorrow. That eat-more-than-you-need appetite and adaptation helped solve the problem of unpredictable food availability.
But today, in most areas of the developed world, food is plentiful and human culture has created new ways of responding to these cravings. Now we have fast food, high in unhealthy fat that plugs our arteries and expands our waistlines, a far cry from the lean game meat our ancestors sought out. Instead of ripe fruits we have sodas and candy bars.
Even knowing the harm eating fat, salt, and sugar can do to us, we still crave them, and unless disciplined, we will choose them over lean meat and ripe fruit. Why?
Because they pack supernormal stimuli. Our brains react to this relatively recent rise of excessive calories on demand as if it’s a good thing, as though we still need to behave as our ancestors did. Our brains reward us. When we eat our favorite food, the pleasure centers in our brain explode with delight. What we experience is not just slight satisfaction, but an intense pleasure released by brain chemicals. Those centers in our brain, mediated by the neurotransmitter dopamine, are called “do-it-again” centers. Not only do they give us a wave of pleasure, they motivate us to repeat the action that brought us such satisfaction.
The pleasure sensation also is an adaptation. It originally helped solve the problem of searching for and securing crucial foods by reinforcing their consumption, rewarding the find, and causing the craving that ensured survival to continue.
So, our illogical craving for these new cultural creations arises from adaptations that helped ensure survival—the cravings that caused our ancestors to seek out fats or sweets, which helped them survive. But these modern foods, packed with more fat and sugar than anything our ancestors ever found or killed, satisfy the cravings with far more intense emotional reward and consequent stimuli than the original game meat or ripe fruit ever provided.
This is why it is not a joke to say that if you understand the psychology of fast food, you understand the psychology of religion. With the design of fast food, we have unconsciously hijacked ancient adaptations to crave and subsequently secure the essential fats and sweets that kept our ancestors alive and fit to reproduce.
We didn’t evolve to crave fast food, but our brains still accept it as adaptive. These fast-food cravings are a by-product. And now they become dangerous, because, uncontrolled, they can lead to health problems our ancestors likely never faced.
Which brings us to religion — or, more specifically, the adaptations from which belief stems.
Is what we crave always good for us?
This essay is adapted from Why We Believe in God(s): A Concise Guide to the Science of Faith, with Clare Aukofer, , which is available for purchase at these paid links: Amazon, Bookshop, and Pitchstone.
J. Anderson “Andy” Thomson, Jr., MD is a psychiatrist and writer. He is also a board member of the Center for Inquiry. He lives in Charlottesville, Virginia.
July 2024