Evolution has molded not only the human body but also the human mind. Indeed, many of the thoughts, fears, resentments, and desires that seem so private and spontaneous have their roots in a vast, impersonal process that occurred long before the individual was born.
Before turning to evolutionary psychology, it might be helpful to look at evolution itself. First, it should be stressed that evolution was not discovered by Charles Darwin, as many seem to believe. Darwin, a 19th century Englishman, simply came up with a new explanation for how biological evolution occurs and how species change. This is known as natural selection. Darwin supported his theory with masses of evidence. However, he knew nothing of genetics or DNA, and it has been left to those who followed him to combine his theories with these new discoveries to form what is known as the neo-Darwinian synthesis.
To begin with, animals are able to reproduce in huge numbers. But life is mercilessly cruel and many of the offspring do not survive long enough to reproduce in their turn. Instead, they are quickly killed off by drought, starvation, infection, or predators. In other words, there is a struggle for survival. Or, to put it more precisely, there is a struggle to survive long enough to reproduce.
But individual members of a species, though very similar, are not identical. Genetic differences exist, producing different traits. If these differences help the individual to survive (to outrun a predator, for example, or endure a famine), then obviously that individual will be able to reproduce, thus passing on any favorable traits to its young. Those who lack the advantageous traits, however, will be more likely to succumb to illness, starvation, or violent attack before they have a chance to reproduce. Thus, over time, the genetic make-up of a population changes and, eventually, a new species develops.
Evolutionary psychology is a new discipline that applies this neo-Darwinian theory to human psychology. It is opposed by believers in the so-called “blank slate” theory, who argue that human psychology is instead shaped by the family, society, and culture in which a child is raised.
Before turning to specific examples, it is worth adding that even those who accept evolution are often uncomfortable with evolutionary psychology. This is particularly so when evolution is used to explain dark, unpleasant subjects like rape and murder. In theory, a rapist could argue that he was not responsible. Rape enabled his ancestors to spread their genes and was thus favored by natural selection. This has in turn left him with urges that were dictated by evolution itself. In other words, evolutionary psychology can be used to defend almost any action. And critics worry that this leaves no room for conscience, free will, or personal responsibility.
All monkeys and apes are curious when young. Observe baby chimpanzees and you will be struck by the similarity between their behavior and that of a human child. Both are inquisitive and eager to play. Just like a young human, a young chimpanzee will eagerly grab hold of a new toy, banging it, shaking it, and dropping it from a great height.
In general, however, other species of monkey and ape lose this curiosity as they age. Human beings do not. This is due to something known as “neoteny”, meaning the retention of juvenile traits into adulthood – something that distinguishes the human species from other mammals. Of course, neoteny has a downside as well, making us weaker and more vulnerable than other apes. But curiosity has also made us more adaptable and imaginative. We are the species that has broken free of its programming. Whereas, say, a rabbit, tiger, or mouse is guided solely by instinct, we have been able to develop reason, science and technology.
Like all the higher forms of animal life, human beings indulge in a great deal of ritualized violence. Wolves, reindeer, hares and numerous other mammals will play fight in order to assert dominance. And you can see the same among adolescent boys, who will often wrestle one another to the ground in acts that are not truly violent but not entirely playful either. Evolution has programmed them to assert their strength and power without constant blood-letting. And, just as a beaten human will often hold up the palms of his hands (the traditional sign of a surrendering soldier as well), so chimps will offer their hands to demonstrate submission.
Another fascinating product of evolution is the ‘come on’ stare used by men about to fight. Go to a rough bar late at night, make eye-to-eye contact with another man, and you are likely to find yourself in big trouble! Human beings know this instinctively, which explains why people tend to look away when speaking to someone face to face. It is also why shy, passive people find it very difficult to look people in the eye. Even University lecturers often say that it takes years of practice before they can stare straight into the faces of their students. And it also explains why many people find sunglasses, especially worn indoors, to be slightly threatening. Though rationally we know it is not the case, the black lense seems like an unblinking stare.
Throughout the vast majority of human history, homo sapiens lived as hunter-gatherers, with the hunt as the central activity. For men in particular, the ritual of going to work has replaced the hunting party. This was especially true up until the middle of the 20th century, when women were more likely to remain at home looking after the children. As with the hunt, the male would leave the safety and security of his base and join with other men to travel to the office (the equivalent of the hunting ground). Indeed, this sense of work as a kind of hunting is reflected in language. Men used to speak of going to the office as “bringing in the bacon” and even today men sometimes talk of “making a killing” in their business dealings.
Unfortunately, there is a toxic side to this. Human beings are essentially tribal carnivores, programmed to form groups or tribes and defend their territory (or hunting ground) against other groups. The violent trouble that often flares in inner cities derives in large part from this instinct. Gangs will even emphasize this separate identity by wearing different colored bandanas and scrawling graffiti on the neighborhood walls.
One of the most interesting areas of evolutionary psychology involves the mismatch between evolutionary history and modern life. The human animal evolved to live as a nomadic hunter-gatherer, not as an I.T. manager in a crowded, noisy city. Indeed, it has even been argued that this mismatch is responsible for a great deal of the mental illness which afflicts modern society.
Take work as an example. Men evolved to hunt in small teams, under the direction of a strong, charismatic male – the best fighter and hunter in the tribe. When they set out on their hunting expeditions, they spent hours moving and tracking, culminating in a rush of adrenalin and excitement as they closed in for the kill. Instead, the modern man often spends his working day in a large office block, surrounded by people he barely knows. His job is usually sedentary and involves staring at a screen, hidden away from natural light. And instead of a single burst of adrenalin to help him catch his prey, his adrenal glands are constantly being stimulated by noise and stress.
Then of course there is his boss. The relationship between a male boss and his male employees is often fraught with tension. Their hunter-gatherer ancestors may have secretly hated the lead hunter, but they could at least acknowledge him to be the toughest, quickest and strongest. A modern man has to take orders from a boss who may in fact be smaller and weaker than himself. This is often bitterly resented; at a subconscious level the employees may feel that, since he lacks physical power and presence, he has no right to order them about.
You can also see this mismatch in the things that frighten us. The average inhabitant of a city like London, Berlin, or New York is far more likely to be killed by a car or a gun than a spider or a snake, and yet the average Londoner or New Yorker will happily cross a street of fast-moving traffic or stand next to an armed policeman. But those same people will shudder with horror as they walk past a spider or a snake in the zoo.
Evolutionary psychology is a fascinating new subject, one that offers all sorts of intriguing explanations for human behavior. And, as our understanding deepens, it may even help us to lead happier, healthier lives.