This evolutionary approach has led to the view that the architecture of the mind is not a general problem solver but rather a collection of systems dedicated to addressing specific problems. In the same way that dedicated mechanisms for solving recurrent problems during human evolution could have emerged through the process of natural selection, culture-gene approaches to understanding human evolution propose that our species possess mechanisms that reliably seek out cultural input.48 In other words, there are genetic dispositions to learn efficiently. The reason for this is that culture changes faster than genes. Unlike examples of cultural learning in animals, humans continually refine, develop and expand on knowledge that is passed on. This is possible because we have brains that are evolved to learn from others. Our efficiency is guided not only from our capacity to communicate, but also by our biases to attend to specific aspects of others that signal who are most valuable as teachers. As we will learn in the coming chapters, babies are tuned into their mothers from the very start in a reciprocal relationship. But they also pay more attention to others who are older, who are the same sex, who are friendly and who speak the same language. Babies are born with dispositions encoded in their genes to learn from those who are going to be most useful to them in terms of acceptance by the group.
Cognition, cooperation and culture
Psychologist Mike Tomasello at the Max Planck Institute for Evolutionary Anthropology in Leipzig is one of the world’s leading experts on what makes us human. He studies the development of children and how they compare to other primates. He believes that the traits that distinguish humans from our primate cousins are our capacity to think about others, cooperate with them and share ideas and behaviours. All of these are necessary for cultures to thrive. Human culture differs from any other social groups in the animal kingdom because there is a cumulative build-up of knowledge and technologies that is passed on from one generation to the next. With every generation, our world becomes more complex because we educate and share information by cooperation. In this way, knowledge and understanding ‘ratchet up’, with each successive generation expanding and improving the complexity and collective knowledge of the group.49
Other animals also live in groups and exhibit a host of social skills for working out what others are thinking, but these abilities are mostly restricted to situations where there is a potential fight or conflict. Most non-human primates are opportunists, only on the lookout for situations where they can take advantage of other members for either food or sex or to establish a better position in the dominance hierarchy. There are examples where chimpanzees will help others, but these are mostly situations where there is the potential for some personal gain.50 In contrast, people will sacrifice personal gain for others. They will even spontaneously help strangers who they will never meet again. The capacity for altruism seems to be characteristically human. Examples of animal altruism are rare and restricted to those species that exhibit strong codependence, such as marmosets. In these cases, it is strategically in their interests to be promiscuously prosocial to increase their likelihood of breeding.51
Humans may be opportunists too, but all societies are held together by tacit assumptions of reciprocity and moral codes to prevent individuals taking advantage. These are the rules we abide by. Some of these codes are enshrined as laws. We enter into social contracts where we submit to authority or the state on the assumption that those who abide by the rules will benefit, whereas those who violate or break them will be punished. Members who benefit from these social arrangements do not even have to be family. Indeed, when you think about it, much human sharing of resources is altruistic – doing good deeds for the benefit of others who remain anonymous without necessarily benefiting ourselves.
No other animal on the planet behaves as altruistically as we humans do. Of course, there are some species, such as worker ants and bees, that make the ultimate sacrifice for the good of the nest or the hive when it comes under attack, but they do so because they are genetically closely related to those that benefit. Evolution has programmed their brains to be self-sacrificial. Humans are different. We cooperate with others because it makes us feel good. It is the thought of helping that is the reward, because we feel connected to the group. These feelings are the emotions that motivate us to be prosocial towards our fellow man (or woman) and fuel the drive towards altruistic collaboration, cooperation and ultimately human culture. However, we are not slavish drones that automatically bend over backwards to help anyone; we are always on the lookout for those who are trying to cheat the systems of reciprocity. We are inclined to lend a hand but we will seek retaliation if we believe we have been wronged. In order to make these sorts of decisions we have to have brains that are sophisticated enough to interpret others in terms of their motives, their goals and their affiliations.
What makes the human brain different?
For many animals, the problems of living long enough to reproduce were basic and immediate – how to navigate the world to find food, avoid harm and so on. Solitary animals figure these out for themselves because this is how they have evolved. Other animals that live in groups evolved the capability for coordination and cooperation for mutual benefit. For them, the environmental pressures they had to adapt to were not only physical, geographical or climate-based but also social. In a group, there would have been multiple potential mates competing to pass on their genes. This led to the evolution of social behaviours that increased the likelihood of successful breeding within a group.
This increase in social skills is considered one of the reasons that primate brains grew larger and why our species in particular have become the most skilled at interacting and learning from others. But then the human brain began to shrink again with the birth of large civilizations, when we started to live together more peacefully. It could be that humans went further than all other social animals by developing culture – the ability to communicate, to share ideas and knowledge, to engage in ritualistic symbolic activity and develop rules about how to behave for the benefit of the group. We had to learn to live together in greater harmony as our numbers started to increase. We needed to learn to become diplomatic. While physical environments tend to be static, social environments by comparison are constantly changing and providing considerable feedback, which in turn changes the dynamic of the interaction. In short, expertise in social interactions required considerable processing power and flexibility.
To enable humans to do this, we developed long childhoods to provide sufficient time and resources to ensure that our offspring were educated in the skills necessary for harmonious social living. Why else would humans have evolved into the species that spends the longest proportion of their lives dependent on adults? This amount of time was an evolutionarily big commitment for both parents and their offspring. With domestication came wisdom passed down the generations. We may have taught our own children some basics, but there was more to learn from the group. Our ability to communicate meant that our children could learn more about the world they needed to negotiate by listening to others without having to rediscover everything from first principles. But to benefit from that, the most critical knowledge they learned during childhood was how to be liked and valued by others – in other words, how to behave.