5
Evolution in Warp Drive
Darwin formulated his theory of natural selection in terms of variation, selection, and heredity, which is a resemblance between parents and offspring. At the time, the fact of heredity could be easily observed but the mechanisms of heredity were mysterious. That’s why the work of Gregor Mendel (1822–1884) was regarded as such a breakthrough. Mendel was a contemporary of Darwin, but the significance of his work was not appreciated until the early twentieth century. Here at last was a mechanistic explanation for heredity that everyone had been looking for.
Thus began the study of genetics, which became an enormously sophisticated science, especially after the identification of DNA as the molecular conveyor of information by James Watson, Francis Crick, and others in the 1950s. Along the way, however, a faulty inference crept in—that genes are the only mechanism of inheritance. Around the world, for experts and novices alike, when you say the word “evolution” most people hear the word “genes.”
Yet, if you were to ask the simple question “Are genes the only way that offspring resemble their parents?” even a novice would be able to answer “No.” Offspring speak the same language as their parents, for example, and this has nothing to do with genes (other than the role genes play in language acquisition). Myriad other traits are also transmitted culturally rather than genetically. Shouldn’t cultural inheritance mechanisms be included along with genetic inheritance mechanisms in the study of evolution?
Clearly, to fully appreciate the relevance of an evolutionary worldview, we must think about evolution in a way that includes but also goes beyond the genetic. In this chapter I will tell three stories about other evolutionary processes: our immune systems, our capacity to learn as individuals, and our capacity to change as cultures. Each of these processes occurs far more rapidly than genetic evolution. But they are also products of genetic evolution. In other words, genetic evolution spawned other evolutionary processes and then coevolved with them, a process that is still ongoing. This expanded view of evolution is highly relevant to policy formulation. Not only must we see the fast-paced changes swirling all around us and even within us as evolutionary processes, but we must construct new evolutionary processes to adapt to our modern environments.
OUR IMMUNE SYSTEMS
When we die, our bodies start decomposing immediately as the microbes that are already within us run riot. The fact that this does not happen while we are living is due to our immune systems, a mind-boggling array of adaptations that evolved over hundreds of millions of years to keep our healthy microbiomes within bounds and weed out infectious agents.1 The vertebrate immune system includes some components that are called innate because they are inherited from our parents and do not change over the course of our lifetimes. For example, when you get a splinter, your immune system cells already present at the site release chemicals that increase blood flow to the area, make the vessels more porous so that fluid from the capillaries can leak out into the tissues, and stimulate the nerves, which we subjectively feel as pain. Other chemicals, called “cytokines,” diffuse outward and recruit additional cells to the site, much like the pheromones emitted by an angry wasp colony. The response will be much the same if you are eight or eighty.
Other components of the immune system are called adaptive because they are capable of rapidly changing within our bodies. This is a good thing because the innate component alone could not keep pace with rapid microbial evolution. Here is a glimpse of how the adaptive component of the immune system works.
At this moment, about 3 billion B-cells are coursing through your veins. They are the cells that create antibodies. An antibody is a molecule that is capable of latching onto an organic surface. Any given antibody can only latch onto a narrow range of surfaces, but the B-cells produce roughly 100 million different antibodies that collectively can latch onto almost any conceivable organic surface. This is the “variation” part of an evolutionary process.
When an antibody attaches itself to a foreign object such as a bacteria, it tags the object for destruction and removal by the innate components of the immune system. At the same time, it stimulates the B-cells that created that particular antibody to multiply and ramp up production. This is the “selection” and “heredity” part of an evolutionary process. A single B-cell can divide repeatedly to become 20,000 cells within a week and each cell can pump out 2,000 antibody molecules every second. In this fashion, the antibodies capable of fighting a given infectious agent become more prevalent while the other antibodies remain at a baseline level.
So the adaptive component of the immune system is a rapid evolutionary process that includes the three ingredients of variation, selection, and heredity. Why is it important to keep this in mind? Because it means that Tinbergen’s four questions, which organize the study of genetic evolution, can also organize the study of the immune system. For example, when two people get the same disease, they do not necessarily produce the same antibodies. More than one antibody is capable of latching onto the disease and which one gets created and amplified in any particular person is a matter of chance, just like the adaptations that evolve in Richard Lenski’s E. coli experiment (the history question).
B-cells are part of the adaptive component of the immune system.
There are four main points to note about the immune system for the sake of this chapter, and these same points apply in novel ways to individual learning and cultural change. First, the ability to create 100 million antibodies and to select the ones that bind to antigens did not happen by a happy accident. They are elaborate products of genetic evolution operating over hundreds of millions of years. The adaptive component of the immune system is an example of an evolutionary process built by another evolutionary process.
Second, the adaptive component of the immune system supplements and works in close association with the innate component. For the most part, our microbiomes are kept within bounds and infectious agents are weeded out by mechanisms that we inherited from our parents and that do not change during our lifetimes. Antibodies play the essential but relatively modest role of tagging the infectious agents, whose removal is left to innate mechanisms. To understand the immune system, we need to appreciate both its innate and its adaptive components.
Third, the immune system requires elaborate cooperation among its component parts. Dozens of cell types must interact with each other in just the right way. This symphony of cooperation came about by between-organism selection. Organisms with poorly coordinated immune systems were not among our ancestors.
Fourth, the immune system evolved in the main to increase our survival and reproduction as individuals—but that admits exceptions. Just as the smoke detectors in our homes and intruder alarms in our cars go off inappropriately, so do our immune systems, forming antibodies against harmless substances, even when they are working according to their design. Real trouble starts when our immune systems encounter novel environments that cause them to go haywire, as we saw in chapter 3.
I have featured the adaptive component of the immune system in part because it is a fascinating and important example of rapid evolution in its own right, but also because it provides a frame of comparison for our next example.
OUR CAPACITY TO LEARN AS INDIVIDUALS
The immune system’s job of fighting diseases is only one of many challenges that organisms must overcome to survive and reproduce in their environments. They must also avoid predators, find food and mates, battle the elements, and fight or cooperate with members of their own kind. Every individual’s encounter with these challenges will be unique, calling for an impressive degree of behavioral flexibility. In one example, researched by Dr. Michael F. Benard at Case Western Reserve University, the tadpole stage of the Pacific Chorus Frog can inhabit one of three different environments: 1) bodies of water without predators; 2) bodies of water with fish predators, which actively pursue their prey; and 3) bodies of water with insect predators, which ambush their prey with deadly strikes of their jaws.2 Bodies of water seldom have both types of predators because the fish eat the insects along with the tadpoles.
Each of these environments calls for different adaptations to survive and grow to the adult stage of the life cycle. The tadpoles have evolved to detect which environment they inhabit from chemical cues in the water and to express the appropriate adaptations, much as the immune system detects and responds to the presence of an invading infection. This involves not only a change in behavior, but a whole-body makeover. In the absence of predators, they move around freely in search of food. In the presence of fish predators, they remain still as much as possible and are morphologically adapted to escape in a burst of speed when detected. In the presence of insect predators, they also remain still as much as possible and are morphologically adapted to direct the predator’s attack to the fringe of the tail, where the tadpole can get away, rather than to its body and vital organs. This is not just speculation because Benard could actually cause an evolutionary mismatch to take place in the laboratory. When he raised tadpoles with chemical cues from fish and then exposed them to insects (something that seldom happens in nature), their mortality was greater than for tadpoles raised with chemical cues from insects. When he raised tadpoles with chemical cues from insects and then exposed them to fish, their mortality was greater than for tadpoles raised with chemical cues from fish.
This kind of flexibility is like the innate component of the immune system: a fixed repertoire of adaptations that evolved by genetic evolution, waiting to be triggered by the appropriate environmental signals. Other forms of behavioral flexibility are more open-ended, like the adaptive component of the immune system. The organism behaves in ways that are more or less arbitrary (the variation part of an evolutionary process); some ways are sensed as more rewarding than others, and these behaviors are expressed more frequently (the selection and inheritance parts of an evolutionary process). Thanks to this kind of open-ended behavioral flexibility, organisms can adapt to their environments during the course of their lifetimes in ways that can go beyond the fixed repertoire of behaviors that evolved by genetic evolution.
In many species of frogs and toads, the tadpole stage has evolved to have a whole-body makeover in response to the presence and type of predator in their environment.
The branch of psychology devoted to open-ended learning is called behaviorism, and its most famous proponent was B. F. Skinner (1904–1990), inventor of the famed Skinner box, an apparatus that enables the environmental inputs experienced by an animal to be controlled and its behavioral outputs to be recorded with scientific precision. Skinner claimed that animals could learn to do just about anything by trial-and-error learning. He even trained pigeons to play Ping-Pong by rewarding them with food pellets for scoring against their opponent—a behavior that certainly never existed during their entire previous history as a species!
So there is an important comparison to be made between the immune system as an elaborate set of adaptations that evolved to fight disease and our behavioral flexibility as an elaborate set of adaptations to surmount other environmental challenges. However, the study of learning did not proceed along the same path as the study of the immune system. What has become conventional for the latter has yet to be achieved by the former. A brief history of behaviorism will help to explain why a fully rounded “four-question” approach to the study of learning has taken so long to develop.3
At the beginning of the twentieth century, the physical mechanisms that cause us to behave as we do were as mysterious as the mechanisms of genetic inheritance. The techniques required for cognitive psychology and neurobiology to become sciences didn’t exist yet. Speculations on how the mind worked were exactly that: speculations that relied on introspection and little else. Against this background, behaviorism originated as cutting-edge science because it enabled learning to be studied purely on the basis of environmental inputs and behavioral outputs and didn’t require mechanistic knowledge about how the mind works. Stated in terms of Tinbergen’s four questions, behaviorism could make progress on the function and history (meaning the history of reinforcement) questions, while largely ignoring the mechanism and development questions. On this basis, it became the dominant tradition in academic psychology during the first half of the twentieth century.
Eventually, the limitations of behaviorism became apparent. Organisms were not entirely blank slates in their learning abilities, and techniques were becoming available for studying how the mind works in a mechanistic sense. Skinner opposed many of these developments. He derided the study of mechanisms (calling it “mentalism”) and overreached in his claims for what trial-and-error learning could explain. As a result, scientific progress took the form of a revolt rather than continuous change. It was called the “cognitive revolution.”4 During the second half of the twentieth century, cognitive psychologists thought of the mind as a computer, and the main objective was to understand its circuitry—Tinbergen’s mechanism question.
Behaviorism had become passé within academic psychology—even taboo, because it treated the mind as a blank slate and didn’t factor in the mechanisms at work in the brain—but it didn’t die out entirely. Instead, it flourished in the applied branches of psychology, where the main objective is to change behaviors in the real world.
Then, starting in the 1980s, the cognitive revolutionaries were challenged by a new breed of upstarts who called themselves evolutionary psychologists.5 The mind is not simply a single all-purpose computer, they said, but a collection of many specialized modules, each a product of genetic evolution that solves a particular adaptive problem faced by our ancestors. These “modules” are like the records in a jukebox, waiting to be played whenever the environment presses the right buttons. Even though the evolutionary psychologists challenged the cognitive revolutionaries about the mechanics of the mind, both camps were united in their scorn for behaviorism and other “blank slate” traditions in the social sciences.
Readers unfamiliar with the world of science might be surprised and a bit amused by all this Sturm und Drang. Scientists are not cold and rational like Mr. Spock on Star Trek. They are flesh-and-blood humans who attempt to build and defend their empires, much like people from other walks of life. The only thing that sets science apart is a set of norms and practices that results in the accumulation of factual knowledge, albeit with many twists and turns along the way. It shouldn’t surprise us too much that one broad area of inquiry, such as learning, might lag behind another broad area such as immunology, even though both end up within the same theoretical framework.
What’s important for our purposes is that we can see the similarities between our capacity to learn as individuals and the innate and adaptive components of the immune system. Here are some insights that result from the comparison. First and foremost, you can begin to think of yourself as a rapidly evolving system in your own right, adapting to your environment over the course of your lifetime. Who you are is determined in large part not by your genes (other than the genes that make open-ended learning possible), but by your environment and the behavioral options that you ended up adopting to solve the problems of your own existence. And just as you adapted to past environments, you can further adapt to your current environmental challenges. You have the capacity for positive, even transformational, change.
Yet this does not mean that your personal evolution is an “anything goes” affair, any more than you can consciously choose your own antibodies. The mechanisms that make open-ended learning possible are extremely complex, and most of them take place beneath conscious awareness. If we want to consciously direct our future evolution, we must understand and work through these mechanisms.6
Furthermore, as we have seen for genetic evolution, what’s adaptive in the evolutionary sense of the word isn’t necessarily good or right in the normative sense. Genetic evolution often results in adaptations that are good for me but not you, or us but not them, or good over the short term but not the long term. The behaviors that we adopt by open-ended learning have all the same limitations. If anything, behavioral adaptations are even more shortsighted than genetic evolution because the immediate costs and benefits of our behaviors are more perceptible to us than the long-term consequences. You might want to lose weight, but your mind is causing you to dip your hand into the next bag of Doritos. You might want peace on earth, but your mind is causing you to do what it takes to beat out your competitors for a promotion at the office. A lot of cleverness will be required to align our learning abilities to our long-term personal and societal goals.
We also must keep in mind that the adaptive component of our learning system, like the adaptive component of our immune system, works in conjunction with an innate component—a fixed repertoire of behavioral responses triggered by environmental stimuli. The first evolutionary psychologists weren’t wrong to emphasize the modular nature of human and animal minds; they were just wrong to deny that such minds could also include an adaptive component.
To appreciate the innate component of our learning system, consider that all species experience both benign and harsh conditions during their evolutionary histories, resulting in conditional adaptations that are triggered by environmental signals, similar to the conditional anti-predator adaptations in the Pacific tree frog. Nonhuman species don’t fall apart when times get hard—they behave in ways that are well adapted to hard times.7 In many species of birds, stressful environments result in higher levels of corticosterone hormones in the eggs laid by females.8 When hormone levels are experimentally manipulated in the laboratory, chicks that are equivalent in every other respect grow up to be different creatures. Those who experienced higher levels of hormones during development leave the nest at a smaller size, mature their flight muscles more quickly, and have better in-flight performance than fledglings who experienced lower hormone levels. While foraging, they are more active and are willing to take greater risks to find food. These are not deficits caused by stress, and they didn’t arise by trial-and-error learning; instead, they are adaptations to stress-inducing environments that are a result of genetic evolution and lie latent in every bird, waiting to be expressed by the appropriate signal. In fact, even the open-ended learning process is tweaked. Stress-adapted birds are more likely to discount behaviors learned from their parents in favor of behaviors learned from conspecifics or from personal experience. If your mother is stressed, maybe it’s because she doesn’t know things that other birds know or that you can learn for yourself!
Extensive research on laboratory rats shows that stressed mothers spend less time licking their babies. When the amount of licking is manipulated in the laboratory, rat pups that are equivalent in every other respect grow up to be different creatures. Females who are licked less achieve puberty earlier, are more successful at achieving social dominance over other females, are more attractive to males, and have greater success at getting pregnant. Males who are licked less engage in more play fighting as juveniles and are more pugnacious as adults. In short, both sexes become adapted to reproduce as soon as possible, which makes good adaptive sense because in stressful environments there might be no tomorrow. This example is similar to the bird example except that the environmental signal is a maternal behavior rather than a hormone. Stressed mothers are not being neglectful by licking their pups less. If they were to lick more, then their pups would not develop the adaptations for the hard times that they are likely to encounter. In fact, female rats that are licked less as pups also lick less as mothers, even when all other aspects of their environment are held equal. From the pup’s perspective, the signal transmits the experience of their grandmother in addition to their mother.
There is every reason to expect human child development to be influenced by hormonal and behavioral signals in the same way as birds and nonhuman mammals. After all, we are mammals and whatever is unique about our evolutionary history is layered on top of our more ancient pedigree. Children who experience harsh conditions such as poverty, neglectful caretakers, violence, and food shortage grow up (on average) to be different creatures than children who experience more nurturing conditions. They develop roughly the same suite of sociosexual strategies as stress-adapted rats, oriented toward early reproduction. Their open-ended learning abilities are altered. They have an enhanced ability to solve problems that result in immediate rewards as opposed to long-term rewards. At age three, they have a better memory for bad events than good events when recalling what happened during a puppet play. They are better at quickly shifting their attention from one activity to another. They perform better in high-risk situations.
These and other differences have been extensively documented in the child development literature, but their interpretation has been handicapped by lack of a modern evolutionary perspective. Instead, most developmental psychologists assume that development takes place optimally in nurturing environments and becomes impaired in harsh environments, like an automobile that breaks down under severe conditions. The challenge is therefore to fix what is broken, to make so-called at-risk children more like “normal” children. This provides an excellent example of the theory deciding what can be observed. Against the background of the “broken car” model, the idea of behaving adaptively in stressful environments becomes difficult to see.
Later I will elaborate on how an evolutionary worldview can lead to new practical strategies for managing our own personal evolution. For the purposes of this chapter, our capacity to learn as individuals is one of three examples intended to expand our understanding about evolution beyond the genetic.
OUR CAPACITY FOR CULTURAL CHANGE
A point I made about our immune system, which also applies to our learning system, is that it requires elaborate coordination among its component parts. This coordination is a product of between-organism selection.
In principle, information acquired by learning during one generation could be transmitted to the next generation to be refined and extended. However, this would require a high degree of coordination among individuals living in groups. Between-group selection would likely be required to encourage this degree of cooperation.
As we learned in chapter 4, between-group selection operates to some extent in nonhuman social species, but it is often strongly opposed by disruptive selection among individuals within groups, which limits group-level coordination in all its forms. For this reason, adaptations learned by individuals during the course of their lifetimes largely die with those individuals and must be learned anew by the next generation. Cultural traditions do exist in other species, but humans are clearly in a class by themselves. Our ancestors found ways to suppress disruptive competition among individuals within groups, so that between-group selection became the primary evolutionary force. This favored group-level coordination in all its forms, including the transmission of learned information across generations. Cultural evolution began to operate alongside genetic evolution and the two processes began to interact with each other.9
Evidence for cultural evolution is all around us, once we become attuned to it. Joseph Henrich, professor of human evolutionary biology at Harvard University, has a clever way of demonstrating its importance in his book The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter. He devotes an entire chapter to explorers who found themselves stranded in inhospitable climates, such as the Arctic, the Australian outback, or the deserts of the American Southwest. With their supplies running out, the explorers were forced to live off the land, but their individual intelligences weren’t even remotely up to the task of figuring out what to eat, how to procure and prepare it, or how to protect themselves from the elements. Some of them perished and others survived only thanks to the kindness of the native people in the area who called the same inhospitable climate home. The natives were thriving, due not to their individual intelligences, but to a vast storehouse of information that had been learned by their ancestors and transmitted to the current generation without the help of a written language.
Even natives can lose their storehouse of information under some circumstances. In one famous example recounted by Henrich, the island of Tasmania off the coast of Australia used to be part of the mainland but became separated by rising sea levels approximately 12,000 years ago. The human population on the island was sufficiently small that their collective capacity to store and transmit information was diminished. Over time they led a more rudimentary existence, not because their environment was different from the mainland but because not enough heads were available to store culturally acquired information. In another example, during the 1820s an epidemic killed many of the oldest and most knowledgeable members of an Inuit population that lived in an isolated region of northwestern Greenland. The loss was like a collective stroke for the culture. The survivors were unable to make effective bows and arrows, heat-trapping entrances to their snow houses, or kayaks. They were unable to re-create this knowledge, and their population had dwindled by the time they were contacted in the 1860s by another Inuit population from around Baffin Island. Only then did the northwestern Greenland population begin to rebound, thanks to the replenished cultural toolkit obtained from another population.
Once we become attuned to it, the entire pageant of human history, starting approximately 100,000 years ago, can be seen as evolution at high speed, made possible by the transmission of learned information across generations. Our departure from Africa and colonization of the rest of the planet; our ability to inhabit all climatic zones and dozens of ecological niches as hunter-gatherers; our ability to grow food as farmers; the advent of writing; and the exploitation of fossil fuels were all made possible by the generational transfer of information.10 The scientist and priest Pierre Teilhard de Chardin, with whom I began this book, was far ahead of his time when he asked us to imagine humanity as a twig on the tree of life that begins to proliferate so fast that it soon overtops the rest of the tree and eventually results in the coalescence of small-scale societies (“tiny grains of thought”) into larger societies.
So transgenerational human cultural change counts as an evolutionary process, similar to genetic evolution, the immune system, and our capacity to learn as individuals. However, the history of thinking about culture in anthropology and sociology is at least as complex as the history of thinking about learning in psychology. Here is a brief summary to serve as a companion to my summary of behaviorism.11
Darwin’s theory did not exist in a vacuum. It originated against the background of other prominent thinkers of the day such as Herbert Spencer (whom we met in chapter 1), Edward Burnett Tylor, and Lewis Henry Morgan. All of them believed in the unity of humankind—that people around the world are members of the same species with the same basic capacities. They also shared a progressive view of evolution, as we saw with Spencer, in which humanity is on a path toward perfection. Naturally, they thought Europeans were at the forefront, so their stance toward other cultures was to help them become more “civilized.”
Darwin mostly shared these views and in any case shared the stage with these and other major figures as the fields of anthropology and sociology emerged during the late nineteenth and early twentieth centuries. Two dissenters from these views were Franz Boas and Bronislaw Malinowski. Boas was a physicist by training who traveled to Baffin Island as a young man to study the different effects of light in the Arctic. He was so impressed by the ability of the Inuit to survive in such a harsh climate that he couldn’t regard them as lower on the chain of anything. They were the best at surviving and reproducing in their particular environment, and perhaps all cultures should be regarded in the same way. Notice that this view is highly consistent with Darwin’s theory of evolution; Boas was discriminating enough to distinguish between Darwinism (which he championed) and progressive forms of evolution (which he rejected).
Malinowski became intimately familiar with a native culture when he spent the duration of World War I on the Trobriand Islands in the Pacific. Like Boas, he began to appreciate the importance of viewing the world from the point of view of natives in the context of their environments, rather than placing them on a linear sequence from savagery to civilization. This led to a tradition of anthropologists living with the people whom they studied and trying to understand each culture on its own terms. The tradition self-consciously avoided any particular theoretical perspective as premature. The most important thing was to gather information as objectively as possible, which could be consulted by theories in the future. As E. E. Evans-Pritchard, a major British anthropologist during the middle of the twentieth century, described it, the whole business of anthropology is translation, to enable us to see other cultures as the members of that culture do.
This tradition in anthropology was an improvement over the arbitrary view that humanity was on a path toward perfection and led to the accumulation of a stockpile of information about cultures around the world. In the absence of a theoretical framework, however, there was no way to organize the information. The same could be said for the study of human history, which developed as a separate discipline but also became largely non-theoretical or even anti-theoretical, as if there could be no such thing as a unifying theoretical framework. Until Darwin’s revolutionary theory, the study of natural history—the habits of plants and animals—suffered from the same lack of organizing principles.
Franz Boas, widely regarded as the father of anthropology in America, appreciated the adaptedness of each culture to its environment. Here he is emulating the Inuit on Baffin Island.
Traditions in cultural anthropology and other academic disciplines concerned with culture that are driven by terms such as “relativism,” “social constructivism,” and “postmodernism” take the rejection of theory to extremes, even to the point of denying the existence of objective knowledge altogether. The very word “theory” becomes defined as “any perspective.” Science is portrayed as just another social construction, with no more or less authority than any other. Not all anthropologists go to such extremes, but the schism is so great that anthropology departments at some of the most prestigious universities, including Harvard, Stanford, and the University of California at Berkeley, have split into separate departments, like nations that split apart because their citizens just can’t get along. In anthropology departments that remain intact, there is often little communication and much antipathy among the factions, as if they would like to divorce if only they could.
Fortunately, the study of human cultural diversity and change from a modern evolutionary perspective began to take root in the final decades of the twentieth century. Today there is a rapidly growing community of scientists and scholars drawn from a melting pot of academic disciplines who appreciate the meaning of having an evolutionary worldview in a social and cultural context.12
With this perspective, you can begin to think of yourself as not just a product of your genes, and not just a product of your personal experience, but also as one of many members of your culture who collectively contain a vast repository of information learned and passed down from previous generations. This makes you part of something larger than yourself. The information has not just been passed down, but it has also been winnowed through the generations, leaving us with a set of beliefs and practices that helped us to cohere as groups (Tinbergen’s function and history questions).
The cultures we have inherited can be described in functional terms as meaning systems, which receive environmental information as input and process it in ways that result in action as output. If we exist within a well-adapted meaning system, then we arise each morning brimming with purpose and what we feel driven to do is in fact what is required to prosper. Notice that a meaning system can fail in at least two different ways. It can fail to inspire us, or it can inspire us to do the wrong things.
Meaning systems are human constructions. Hence, the tradition of social constructivism in anthropology and sociology isn’t wrong, as long as it’s not conceptualized as outside the orbit of science and evolutionary theory.13 We need evolutionary theory twice over: first, to understand the genetically evolved mechanisms that make cultural evolution possible; and second, to understand the diversity of forms that results from cultural evolution.
An experiment performed on preschool children provides a glimpse of how they are able to soak up the most relevant information from their surroundings while filtering out the noise (Tinbergen’s mechanism and development questions).14 The children watched a video of two adults sitting side by side. The adults are eating different foods, drinking different-colored liquids, and manipulating a toy in different ways. Then two other adults appear and face one of the original pair. Two videos were created in which each member of the original pair was the object of attention. After watching one of the videos, the children were given a choice of which food to eat, which liquid to drink, and were given the toy to manipulate as they saw fit. The result: children were four times more likely to eat the food and drink the beverage and thirteen times more likely to play with the toy in the same way as the person who received the attention of the onlookers.
Another study of guests interviewed by Larry King, the legendary talk show host, analyzed the relationship between King and his guests. Some were socially subordinate to Larry and others were socially dominant, such as former president Bill Clinton. Acoustic analysis of the interviews showed that subordinate guests copied the speech patterns of Larry and Larry copied the speech patterns of dominant guests.15
These and a growing number of other studies show that both as children and adults, what we learn from others is far from random. We rely upon cues, such as who is receiving attention or who is socially dominant. You could call these copying behaviors intelligent, but it is a form of intelligence that takes place largely beneath conscious awareness. The preschoolers didn’t consciously think “Oh! I will copy the person who receives the most attention from the onlookers!” and the adults didn’t consciously think “Oh! I will copy the speech patterns of the person who is socially dominant!” These copying behaviors are smart in the same way that the immune system or our instincts for learning on the basis of personal experience are smart.
Mind you, we do consciously direct our copying behaviors to a degree, just as we consciously direct our trial-and-error learning. We also imagine and work toward social constructions that are entirely new. Henry David Thoreau had this kind of visionary planning in mind when he wrote, “If you have built castles in the air, your work need not be lost; that is where they should be. Now put the foundations under them.” Nevertheless, our conscious efforts at social construction are the tip of an iceberg of mechanisms that take place beneath conscious awareness—and both need to be understood as part of Tinbergen’s mechanism and development questions for the study of cultural evolution.
The products of cultural evolution (Tinbergen’s function and history questions) adapt human populations to their environments much faster than genetic evolution, but they are subject to all the same limitations: at times benefitting me at your expense, us at their expense, or all of us today at the expense of future generations. To overcome these limitations, we must mindfully direct the process of cultural evolution toward planetary sustainability. As we shall see, this provides a “middle way” between laissez-faire policies on the one hand and command-and-control policies on the other—a path that anyone can follow, no matter where they currently exist on the current political landscape.