One possibility is that they desire to be like the person they are copying. Such identification may be important for effective cultural transmission. Copying actions even if they do not yet understand why it was done or modeled the way it was enables children to faithfully acquire proven cultural traditions. It ensures high-fidelity transmission and explains why, in addition to useful behaviors, bizarre, irrational, and superstitious practices survive and even flourish in our cultures. More importantly, it explains how culture can be maintained over generations without shortsighted youngsters abandoning all the hard-learned lessons.
Imitation is critical to normal social and cognitive development. The psychiatrist Justin Williams and the psychologists David Perrett, Andrew Whiten, and I proposed that autism is a disorder that may have its origin in imitation problems. Underlying this problem may be cells in the brain known as mirror neurons. These neurons fire both when you see a particular action, say someone tearing a piece of paper, and when you do the action yourself. In other words, the observation of another’s behavior activates the brain mechanism for doing that same action. The discovery of this mirror system has caused great excitement among neuroscientists because it suggests a neural mechanism involved in imitation and a range of other important capacities including theory of mind, language, and empathy—abilities that are characteristically impaired in autism.10
Humans often copy each other without being aware of it. When we are with close friends, we tend to unconsciously mimic their postures, movements, and the way they speak. Monitor yourself, and you will see what I mean. Such copying is associated with greater mutual liking and has come to be known as the chameleon effect. Research suggests that when you imitate someone (and they do not notice this), they tend to act more prosocially toward you.11 In one study, for instance, people who had been copied by an experimenter for a few minutes would instantly help pick up pens the experimenter “accidentally” dropped, whereas only a few participants who had not been copied helped her. But beware—the power of this finding has not escaped astute salespeople and politicians.
TEACHING IS THE FLIP SIDE of imitation: while imitation is based on the ignorant trying to learn from the knowledgeable, in teaching the knowledgeable party is trying to impart information to the ignorant. Parents regularly interfere in their offspring’s play to instruct. For instance, they may make important aspects of a task salient, partially solve a problem, or select the easiest versions of a behavior to get their child started. Parents provide opportunities for children to learn and practice skills without being harmed. Though psychologists have extensively studied learning in children and pedagogy in adults, rather little is known about the development of teaching in children. An exception is a study on Mayan children in which researchers found that from age four onwards children initiated teaching situations. By age eight they modeled actions and corrected the learner’s attempts, using language to describe and explain their actions.
Language is crucial for our teaching of facts. In teaching skills, however, such as how to play an instrument, a teacher may model and instruct the pupil to imitate. In such cases the two pillars of cultural learning are frequently combined. Learning may be encouraged by drawing attention to the crucial steps, perhaps by slowing down, by breaking down the process into more manageable chunks and teaching them one by one, or by repeating the sequences with the teacher highlighting the value of the reward it can bring. Teaching can be subtle or quite hands-on, as the teacher interferes with the pupils’ attempts, adjusting their body or their mind in the desired way. Without teaching, cultural transmission would no doubt be significantly limited.
Schools and curricula are relatively recent institutionalizations of teaching and learning. Even without schooling, traditional societies transmit important knowledge incidentally as well as in carefully managed situations. For instance, rites of passage may impart knowledge and inform potential teachers that an individual is ready to learn about a new stage of life. Stories are told that harbor diverse lessons for the listener. Though there is great variation in nature and extent, teaching appears to be a cross-cultural universal.
Reflecting on teaching and learning may be less common but can bring many benefits. The teaching of complex skills and knowledge often involves some mental time travel, as a long-term plan may be required to overcome numerous obstacles to future expertise. Considering what is or is not known by a pupil helps devise a method by which the pupil can acquire more knowledge. In this sense, pedagogy must also require some theory of mind. Indeed, teaching competence in young children is associated with performance on theory of mind tasks. The pupils too benefit from a capacity for mind reading, as it can be useful to appreciate the teacher’s purposes. They also crucially benefit from mental time travel. Choosing to practice to get better at something in the future is essential for many types of complex learning.12 As we saw, differential practice must be partly responsible for the great diversity of human expertise. Of course, language immensely improves teaching and learning, as it enables us to directly exchange ideas. Thus all four domains of the mental gap discussed in the previous chapters contribute to our capacity to teach effectively.
BEFORE ANYONE CAN BENEFIT FROM imitation and instruction, someone first needs to invent something worth transmitting. On occasion we might stumble on something by sheer luck, but we often actively pursue new solutions. As we saw in the previous chapter, we have a knack for turning problems into opportunities. This need not mean that each human group depended on geniuses, like Leonardo da Vinci, who single-handedly make considerable contributions to cultural heritage. Minor improvements accumulate. Because cultural inheritance is not limited to transfer from parents to children, adaptive information can spread from any member of a cultural group to any other. Human groups also typically have some contact with other groups and may hence also incorporate inventions and practices from their neighbors. Much of the rapid transfer of ideas was likely due to trading, migration, and war.
A serious concern that arises with today’s interconnected cultures is that we are rapidly losing diversity by importing all the same “memes.” Languages are disappearing, and with them much of the cultural heritage of their speakers. One might argue that barriers are worth breaking down. Globalization and large-scale cooperation works best when we can all communicate with the same tongue. Nevertheless, it may turn out to be critically important to maintain our diverse cultural heritage, so we have variation on which selection can work in the future. Besides, it makes for a more colorful world.
Rather than wholesale exchange, cultures traditionally import subsets of the cultural heritage of other groups and then modify them to their own liking or circumstances. We pass on not only solutions but potential solutions. When people from a preliterate culture saw that an outsider used symbols to account for his goods, this observation may have been sufficient for the group to devise its own symbol system. Although Leonardo da Vinci had no way to successfully construct a helicopter, his idea for such a contraption survived him and was eventually put into action. We can pass on questions, not just answers. Obviously, not every so inherited problem will be solved (e.g., a perpetual motion machine), but as knowledge increases, past visions can become tomorrow’s reality (e.g., Jules Verne’s submarines or solar-propelled spacecraft).
Finally, cultural innovation can be deliberate and goal directed. People set out to find a solution to a problem. With mental time travel, we can even start working on problems that do not yet exist. For example, what are we going to do if a large meteorite heads our way? Indeed, some spectacular attempts have been made to socially engineer cultures themselves. Communism was a deliberate attempt at changing cultures for what was believed to be a fairer, more cooperative future. Yet as we all know, plans do not always work out. Although it is probably the case that cultures primarily evolved from the bottom up rather than the top down, as it were, we can certainly develop some of our culture by choice.13
However it was shaped,
culture is critical to our minds. What would you be without cultural input? Your mind would no doubt be unimaginably different. Other animals raised in human cultural environments, even the language-trained apes, do not quite import our culture the way our children do. We appear to be predisposed to acquiring culture; I will elaborate on this later. First, however, we must challenge human arrogance again and ask whether other animals have not evolved their own cultures.
COOPERATION EXISTS IN THE ANIMAL kingdom. As we have seen, much of this is mutually beneficial symbiosis or can be explained in terms of kin selection. Cooperation with unrelated individuals is unusual. Researchers have proposed that it is rare because effective reciprocal altruism requires sophisticated cognitive capacities, such as a numerical capacity to keep account of the giving and taking in interactions, and an ability to detect and punish cheaters. Nonetheless, a few cases of apparent reciprocity have been noted. Vampire bats, in spite of their sinister image, were famously reported to kindly share blood with weak and unsuccessful unrelated bats. Cuddlier primates depend to a large extend on reciprocal grooming as a social glue. Among chimpanzees, having groomed another increases one’s chances of getting a share of the other’s food. As noted earlier, chimpanzees also form coalitions and reciprocally support each other in fights. These coalitions are the basis of their political struggles. Like us, they are more likely to help those who have helped them.
Furthermore, chimpanzees sometimes seem to know whom best to work with. In one study chimpanzees were presented with a problem in which they had to decide when to recruit a partner to pull in food. The treats were put on a tray outside of the enclosure and could be obtained only when two chimpanzees pulled on the two ends of a string in synchrony. A chimpanzee could let in either of two other chimpanzees by opening their cage doors. Chimpanzees generally recruited whoever was more effective in cooperating previously. Another recent study found that chimpanzees learn preferentially from high-status individuals. We are not the only species to have figured out ways to effectively cooperate with nonrelatives. (Whether other animals have morality to support such cooperation will be discussed in the next chapter.)
Many animals also change their environment and so pass on more to their offspring than merely genes. Though no deliberate planning needs to be involved, a beaver’s dam, an extensive burrow, or a termite mound can significantly alter the lives of future generations—perhaps not entirely unlike our old houses and infrastructure. Yet is there social inheritance of behavior? Ethologists have documented how during a critical period young animals acquire certain characteristics from their parents, such as which traits are desirable in a mate. Such imprinting does not offer much flexibility or room for knowledge accumulation. Do animals teach and learn from each other the way we do? Do they exchange ideas with unrelated others? Is there anything we could justify calling “animal culture”?
Perhaps the most famous case of purported animal culture comes from monkeys. In 1953 a Japanese macaque, Imo, was observed washing sweet potatoes, which had been provided by researchers, to rid them of sand. This behavior spread through the group and so suggested social learning by the monkeys. Some people went so far as to suggest that the behavior spread more mysteriously, and this case comes up in writings of New Age spiritualists. A closer look at the actual spread of the invention, however, suggests little need to appeal to culture—nor to any psychic connections. Imo’s mother learned the trick about three months after Imo. Two years later, seven members of the group did it, and three years later it had spread to eleven individuals. By 1962, thirty-six out of forty-nine animals did it.
The speed of transmission was not exactly rapid, nor did the rate increase with time. If the spread had been the result of teaching or imitation, one should expect it to accelerate as more models become available for the uninitiated monkeys to learn from. Furthermore, monkeys generally brush sand off food. I once saw an ibis, a common wading bird in Australia, wash a potato chip for apparently the same reason. Thus acquisition of the behavior may not be that unusual. It is possible that each monkey acquired the skill individually through trial-and-error learning, though it is quite likely that some social learning played a role.
There is, in fact, mounting experimental evidence that behavioral patterns can socially spread in groups of various species. When pigeons trained to peck through the covers of food were released into a flock of naïve birds, the behavior spread more quickly than in flocks that did not have a model. Such so-called diffusion experiments have become more sophisticated over recent years and examine how the behavior of animals can socially spread in populations of fish, birds, and mammals.
In one study researchers trained one captive chimpanzee to get food from an apparatus in one way and another to solve the same problem in a different way. Each was then returned to their native groups to see how the seeded technique spread. Thirty of thirty-two chimpanzees mastered the technique introduced into their group, whereas none of the control group learned to solve the problem by themselves. In a recent study on orangutans a similar result was obtained. Chimpanzees and orangutans, at least, are capable of socially transmitting these techniques (or memes, if you prefer).
Do our close relatives therefore possess a second inheritance system? There are some indications that they do. The long-term studies of chimpanzees in Africa have documented behaviors of different groups in great detail. Andrew Whiten brought the directors of these projects together to pool their data on potential cultural variations. They mapped behavioral patterns that were common in at least one site but absent elsewhere. For example, chimpanzees at Mahale in Tanzania often groom each other while holding hands in the air, whereas chimpanzees at Jane Goodall’s research site at Gombe, only about 150 kilometers away, do not. At several sites chimpanzees use probing tools to fish for termites and ants. At Gombe, chimpanzees dip for ants by inserting a relatively long wand into a nest and then wiping the ants off with their hand to put them into the mouth, whereas in the Tai forest chimpanzees insert a short stick and so gather fewer ants they eat straight off the stick. Only at a site in the Republic of Congo have chimpanzees been observed to use two sticks, one to thrust into the mound to create an opening and a more delicate one to extract the termites. Chimpanzees at Bossou in Guinea crack nuts with stone hammers, whereas at the Tai forest in the Ivory Coast they also use wooden hammers. At Gombe they use neither. The systematic comparison has yielded between one and two dozen of such traits per group, and an overall current total of thirty-nine such different behaviors.
There are no simple ecological or genetic explanations for these differences. Given that we know that behaviors can spread socially in captive populations, it is now generally accepted that this diversity in behaviors between wild groups is due, at least in part, to socially maintained traditions. In other words, chimpanzees have a kind of culture. Some traits may have been passed on over many generations; recall from Chapter 2 that there is evidence that chimpanzees in the Tai forest already used stones to crack nuts over four thousand years ago.
Subsequent work on Sumatran orangutans identified two dozen such behavioral traditions. They too may hence qualify as having culture. Cetaceans, as well, appear to have multiple social traditions. At Shark Bay in Western Australia, for example, dolphins break off sponges and wear them over their snout when probing the sea floor. Such behavior appears to have no genetic basis and is likely maintained socially. Furthermore, there is evidence they learn foraging strategies from their mothers. Socially maintained behaviors of a single variant have now been documented in various others species—from the foraging techniques of insects and rats to some dialects of birds.
New Caledonian crows, it has been argued, may even have cumulative social traditions. Gavin Hunt and Russell Gray have demonstrated that different groups of these crows cut out three distinct tool designs from the barbed edges of pandanus leaves. The tools are used to extract grubs from crevices; the designs vary from a simple strip to a complex stepped design. The d
esign made at a particular location stays stable over decades. Hunt and Gray made the case that the more complex designs arose from the simpler design. If that is correct, it would be the first recorded instance of accumulation of technology in a nonhuman animal. Subsequent studies on the learning of the manufacturing skill, however, suggest that individual trial-and-error learning plays a pivotal role. Social transmission may be limited to providing the young with exposure to tools and tool use.
In sum, some animals are capable of behavioral traditions. Admittedly, the number of socially maintained traits is low. The most prolific traditions are found in our closest relatives, but in comparison to the tens of thousands of “memes” that characterize each human culture, even the number of traits chimpanzees maintain socially is exceedingly small. Scholars disagree over whether to call animal traditions “cultures” at all. I do not mind either way. In either case, there is a big quantitative difference between humans and our closest animal relatives. And it seems likely that a qualitative difference is responsible for this. Other animals do not appear to fully exploit the powerful potential of a flexible, cumulative cultural inheritance system. They do not show anything like the ratchet effect by which numerous solutions are continually refined and improved. Given the limits in language, mental time travel, theory of mind, and innovation discussed so far, this may not be a surprise. A key reason may be that animals’ cultural transmission mechanisms are not appropriate for the spread and accumulation of vast amounts of information.
The Gap Page 21
