The reflector of the Arecibo Radio Telescope in Puerto Rico covers an area of eighteen acres. Its antennae, suspended 450 feet above the reflector, are so sensitive that the telescope could pick up the signal emitted from a mobile phone half a billion miles away. This instrument is perfectly suited to listening for signs of alien life.
Arecibo is the home of SETI, the search for extraterrestrial intelligence. Every night this enormous dish probes likely star systems for signals that may indicate the existence of intelligent life. For each patch of sky the system crawls slowly along the radio dial, searching as many as two billion frequencies and spewing out vast amounts of data for analysis. Within this morass of electromagnetic noise the SETI team hope to find a pattern they cannot explain – signals that are not caused by interference from a telecommunications satellite, or the sweeping beam of radiation from a pulsar. SETI astronomers sit dreaming at screens through the Puerto Rican night, hoping for the magic moment when the system flashes up the message: ‘Signal found – origin unknown’.
Is their mission futile? There are five million patches of sky to scrutinize, and the search is bedevilled by interference from an increasing number of man-made satellites. Even if there is intelligent life out there, the sceptics say, the chances of picking up an alien news bulletin amid so much random noise are pretty much zero. But even when all five million star systems within Arecibo’s sights have been searched, analysed and cast aside as electromagnetic junk, the critics will not be able to claim victory. There will always be higher-definition, more sensitive telescopes able to focus on more distant star systems.
Whether or not SETI eventually meets with success, we cannot fail to be awed by the extraordinary possibility of intelligent life outside our own solar system. It has value not necessarily because intelligence is a gift from God, nor because we humans, as intelligent beings, have any inbuilt moral worth. Intelligence is precious in the same way as a flawless, deep blue diamond is precious: it is rare, beautiful, and appears to be not of this world.
Human consciousness is often portrayed as pure and all-knowing reason that can escape the confines of our biological existence. At the end of Stanley Kubrick’s and Arthur C. Clarke’s film 2001: A Space Odyssey, the future of mankind is depicted by some kind of space-child in a ghostly floating bubble, watching over the earth and its people. But we are not free-floating souls, set free from bodily needs and experience. Our minds are rooted firmly in our evolutionary past. Our reason is bound up in layers of instinct, of prejudices, desires full of both selfishness and kindness, underpinned by a will to survive and a will to reproduce.
One interpretation of Kubrick’s epic is that the black monoliths were left by alien visitors as a means to hasten the arrival of intelligent life. They appear to act as way-points in the evolution of our species: the first, which appears one day implanted in the soil of the African plains, encourages ape-men to pick up rocks and bones and use them as tools; when the second monolith is uncovered on the moon, we are impelled to explore the rest of the solar system, an event that marks the beginnings of our detachment from Earth, like fledglings leaving a nest; the third gives birth to some kind of disembodied spirit, the ‘space-child’, an image of our future that is both absurdly fanciful and wholly terrifying.
The true story of human evolution is hardly less fantastic. In this book, I want to examine, from its origins in the east African savannah, the legacy left by those aliens who really were responsible for the birth of modern man: Australopithecus, Homo habilis and Homo erectus.
Most thinking people now fully accept the basic theory of evolution. Few people, except perhaps the creationists,1 have much of a problem with the idea that humans descended from the apes and that apes themselves evolved from more primitive mammals. But while people have no problem with the idea that our general shape and structure are derived from other creatures, fewer consider, let alone accept, the psychological implications. Homo sapiens not only looks, moves and breathes like an ape, he also thinks like one. Not only do we have a Stone Age body, with many vestiges of our past, we also have a Stone Age mind. The pressures to which we have been exposed over millennia have left a mental and emotional legacy. Some of these emotions and reactions, derived from the species who were our ancestors, are unnecessary in a modern age, but these vestiges of a former existence are indelibly printed in our make-up.
So this book is essentially about the instincts that intrigue all of us. What, for example, drives a man like the mountaineer Joe Simpson, abandoned and dehydrated in dire weather with a broken leg and stuck deep in a mountain crevasse at over twenty thousand feet, to ignore his pain, above all refuse the comfort of sleep and spend three days crawling back to base-camp in a semi-conscious state? How is it that so many apparently happily married men fantasize about pretty, slim young women seen on a tube train, or risk the happiness of their partners, their children and their own peace of mind on a transient sexual experience? Why is it that so many thousands of people – mostly, but not exclusively, male – will spend their whole week entirely focused on whether Arsenal will win their next crucial football match against Manchester United, or whether the Arizona Diamondbacks can beat the New York Yankees in the baseball World Series, when they are overweight, smoke too much and have no sporting ability themselves? What stimulates that urge to press the pedal as hard as possible at traffic lights to make the fastest getaway? Why be surprised when fascists such as Monsieur Le Pen or Herr Haider are able to appeal successfully to the deeply instinctual racist views of so many people? How is it that humans show altruistic and empathetic behaviour when there seems no possible benefit in return? And how is it that so many people still hold religious views and profess belief in God when the notion of an all-powerful being is irrational?
This book examines these human instincts: survival, sexual drive, competition, aggression, altruism, our search for knowledge and our need for something more, perhaps the divine. Though we have travelled far in time, and moved away from the savannah which first nurtured us, it is there we must first look to find some of the answers.
Five million years ago, our hominid ancestors climbed down from the trees in the thinning forests to try their luck on the savannah. They were forced by an encroaching Ice Age to adapt to a new environment, a place with fewer natural resources than the vegetation-rich forests and little physical protection from predators. Here, a slow and vicious drama of natural selection would be played out over two hundred thousand generations as the ape-men struggled to compete with animals that were faster, stronger, hardier, more poisonous and fundamentally more suited to the violence, mayhem and weather of savannah life.
We began this life on the savannah as Australopithecus with a brain the size of a chimpanzee’s; over the next three million years it tripled in size. Our brain, and the mind it housed, appears to have been our secret weapon and the solution to the problem of survival. An increasingly complex mental architecture began to develop. Alongside an unprecedented expansion of the sheer number of brain cells (up to our present level of around one hundred billion nerve cells) came an increasingly sophisticated mind. We continued to evolve an array of instincts that went hand in hand with an extraordinary jump in learning, emotion and rationality.
We learned how to make and use tools. We discovered fire and the uses to which it could be put. We became curious about the wider world, and started to explore. We began to talk to one another, which allowed communal living to become more complex and more successful. Small groups of hungry hunter-gatherers could pool their resources, exchange crucial information about themselves, their environment and the availability of water, food or fuel. Larger groups became possible, held together by complex and emotional threads of co-operation and kinship. Increasing complexity and division of labour allowed us to put down roots, build civilizations and invent a rich cultural life.
As a species, we are not physically designed for large and anonymous cities, low-level stress, fast food, addictive drugs and the fracturing of communal life. Whoever invented nuclear weapons was not thinking about the ease with which we form alliances and turn to violence against our enemies. The pursuit of material wealth and status often involves the splintering of family units, and we have emotional needs and desires that are not always fulfilled. We were used to the gossip and intrigue that grew from a close-knit and inter-dependent group; now we must be content with EastEnders.
So there is tension between our Stone Age instincts and the stresses and strains imposed by post-industrial civilization. We are forced, as a species, to walk through life laden down with the genetic baggage of five million years of savannah psychology and the inherited traits that preceded the hominids.
This genetic baggage is the subject of this book. But first, let me try to define what I mean by the word ‘instinct’. What does Charles Darwin have to say on the matter? ‘I will not attempt any definition of instinct,’ he writes in On the Origin of Species. ‘It would be easy to show that several distinct mental actions are commonly embraced by the term; but everyone understands what is meant when it is said that instinct impels the cuckoo to migrate and to lay her eggs in other birds’ nests.’
So much for the father of evolutionary theory, you may say. But Darwin was right to point out that none of the characters one associates with the term ‘instinct’ will turn out to be cast-iron universals; there will always be exceptions. Of course, we should have a working definition, and it must turn on the distinction between the mind we are born with and the mind that is ‘made’, via learning, culture and socialization. Instinct, then, is essentially that part of our behaviour which is not learned. Nevertheless, our environment (and hence our learning) may have a powerful effect on the way our instincts are expressed. Instinct is those elements of human action, desire, reason and behaviour that are inherited, and those instincts which are specifically human are those that were honed during our time on the savannah. Nowadays we know a great deal more about inherited qualities than Darwin ever did – we know that they are transmitted through genes.
The completion of the sequencing of the human genome is a landmark in the history of the human sciences. One key figure in this international research programme was John Sulston, head of the UK Sanger Institute. There is an oblique and evocative portrait of Sulston, by British artist Marc Quinn, housed in the National Portrait Gallery in London. It is the gallery’s first ‘conceptual portrait’. It does not exhibit the face of its subject; instead, within a thick stainless-steel frame, rows of translucent beads sit suspended in agar jelly. Each bead contains millions of tangled strands of DNA, chemically amplified from a sample of Sulston’s own genetic material, derived, incidentally, from a sample of his sperm.
It may be difficult to grasp the scale of the achievement of Sulston and his fellow researchers, such as the Americans Francis Collins and Eric Lander. In 1985, the various luminaries in the field first got together in Santa Cruz to discuss the idea and concluded that it was basically unfeasible. But in 1988 the project was given its official seal of approval by the American government. Some people likened the task to the moonshot, but for those involved it felt as though they had promised to put a man on Mars. That feeling quickly changed with rapid advances in DNA-sequencing technology and increasingly heavyweight computer firepower, and the Human Genome Project was completed in 2001. The publication is a list of three billion letters that represent the chemical rungs of the DNA double helix, denoted by the letters A, T, G and C. It runs to over six hundred thousand pages of A4, and in book form would take up 270 feet of shelving space.
Within this expanse of code lies the recipe for the development of the human body. While all of us (unless we have an identical twin) have minuscule variations, the vast majority of the chemical code is identical from person to person. That is why it makes sense to call it ‘the’ human genome. Roughly, one out of every thousand letters will be different from individual to individual. Within these differences lie the variations in human physiology, our hormonal balance, our tendencies to develop cancer, or to have blue eyes. But six hundred thousand pages of code is a big haystack in which to find these specific genes and link them to their ‘phenotypic’ effect – the manifestation of a gene’s action in the organism.
The development of the human brain is determined largely by this genetic code. But the details of the cognitive workings of the brain are still largely a mystery. Investigation of its physical structure does not get us far, and much of our medical treatment is crude; it’s as though I were given a screwdriver and asked to discover the details of a computer operating system by opening up the plastic case and examining the contents. The analogy is perhaps apt, for the human brain is not just like a computer – it is a computer, of sorts. Within its fast and flexible neural networks are data processors, memory caches, behavioural algorithms, logic-solving programmes, fast-response mechanisms, and inputs and outputs to the world outside. The best way to investigate this organ is not to open up the case, it is to boot up the software and watch it in action.
The twentieth century claims impressive scientific achievements, beginning with Einstein’s theories of special and general relativity, which audaciously challenged the orthodoxy of Newtonian physics. Relativity soon proved itself by accounting for observed peculiarities in Mercury’s orbit and accurately predicting how starlight would appear to bend around the sun during a solar eclipse. The world was granted an extremely visible and violent confirmation of the accuracy of Einstein’s theory when the USA dropped atom bombs on Nagasaki and Hiroshima.
But what about the human sciences, and attempts to cast light on ‘human nature’? Anthropologists have returned from far-flung exotic islands, as well as inner-city ghettos, with wonderful stories of cultural oddities, bizarre and extraordinary rituals and beliefs. Some have attempted to construct grand and wide-ranging theories on how human nature and cultures across the world and across time are similar in some ways and different in others. But after a time their theories, such as functionalism or structuralism, fade away or are discredited. Professor Clifford Geertz, the highly respected anthropologist from Princeton University, is right to point out that anthropologists are not in the business of conducting laboratory experiments. The studies, he says, that attempt to show that the Oedipus complex appears to be ‘backwards’ among the Trobriand Islanders, or the theory that the Pueblo Indians are entirely non-aggressive, are interpretations rather than ‘scientifically tested and approved’ hypotheses.
Human behaviour is fickle and unpredictable. Just because Mr Pooter, the unassuming protagonist of The Diary of a Nobody, has caught the quarter-to-nine bus to the City every morning for twenty years does not mean that we can rely on him to catch it tomorrow; indeed, one does not have to wait long to find out that Mr Pooter does miss the bus, on account of an argument with a delivery boy. Mercury’s orbit, on the other hand, is highly predictable, now that relativity has refined our Newtonian model of the movement of heavenly bodies, and unless it gets hit by a wayward asteroid or comet (an event that we could in any case predict) it will remain in this pattern until the sun burns itself out.
Day-to-day behavioural possibilities are endless. Imagine you’re in a restaurant, eagerly awaiting your supper. You’ve missed lunch and you are like one of Pavlov’s dogs, drooling at the thought of the grilled piece of sirloin you have ordered, medium rare. The waiter puts down a plate in front of you, but the steak is not just well done, it’s charred black and tough as old boots. Your heart sinks. What do you do? Send it back? Make a scene? Point out to the waiter that it’s overdone, and then eat it anyway? Wait what will seem like an eternity for a new steak? Or simply walk out of the restaurant and go to Burger King instead?
Now, imagine a particle of dust is floating through a room, illuminated by a shaft of sunlight streaming in through one window. The speck of dust will follow a particular track in three-dimensional space, its movement affected by a number of variables: draughts blowing through an open window, sunlight heating the air and creating thermals that lift the particle skywards, unpredictable eddies and vortices that spin off from these currents of air, and perhaps the extremely rare occurrence of the mite colliding with another airborne particle. Finally, there are the actions of gravity and air resistance, forces that act on the dust particle just like they act on any other object falling through the atmosphere. The track is more likely to be full of twists and turns, full of shifts one way and then the other. At any one point in time two or more of these forces may be acting simultaneously. Some of them, like the sunlight thermals and gravity, may act in opposite directions, and cancel each other out. Others will act in concert, speeding up the progress of the dust speck in one direction.
Just as the speck of dust is at the mercy of many forces, so is human behaviour. We are pushed and pulled in all directions by many different biological, cognitive and cultural forces. Some of these may oppose one another, and some may pull in the same direction. It is entirely possible that two instinctual tendencies may act at odds to each other. But that does not mean these forces cannot coexist; it just means that the track through space is more difficult to understand. Just because we have one adaptive mechanism that promotes violence and another that promotes co-operation does not mean that our explanations of these forces are confused. We are pushed one way and pulled another, and our challenge is to try to disentangle the forces and explain their origins.
Chaos theory tells us that the track of the dust particle will be extremely difficult, if not impossible, to predict in advance. The reason for this is related to the butterfly effect, which theorizes that the flutter of the wing of a single butterfly in China can ultimately affect the course of a tropical storm in the Caribbean. Tiny shifts in initial conditions have a critical effect on the final outcome of a chaotic system, and this applies as much to human behaviour as it does to the physical world. It is impossible to model our behaviour because there are too many factors involved, each with the potential to wreak the same havoc as the flutter of the butterfly’s wing. And there is an added complication: humans apparently have free will.
Explanation of a great deal of human behaviour is an extraordinarily complex process. It is the product of many different factors – instinctive, physiological, rational and emotional – and prediction becomes impossible. Laboratory experiments have shown that the time it takes for a person to react to a flash of light varies, and it varies according to no discernible pattern. Random output of this kind may be useful if one is being chased by a lion; we may change direction, jumping from the left to the right, in an unpredictable way, and we may be a little bit more likely to escape intact. Randomness, then, is an intrinsic part of our neural make-up. One evening you may eat the steak, and the next you may assault the waiter.
But we can make valid assumptions about how life must have been on the savannah and how early man might have reacted to many experiences. We know that the basic physical principles on this planet held fast. There was night and day, sunlight and rain, and variation in temperature. There were hills to climb, rivers to cross, and occasional droughts. We know that there was an array of major predators, mostly big cats, because we have found their bones. Hominids were in danger of being eaten. We know that there were herds of antelope, deer and other herbivorous mammals that were prey for the cats, and possibly for hominids too. Plant life would have offered nourishment, but it would also have harboured venomous insects as well as producing poisonous berries.
We can be confident that the ground rules of the mammalian lifestyle remained intact. Hominids on the savannah needed to eat, drink, keep warm at night and sleep. We aged. We went through puberty, and we had sex. Women fell pregnant and nursed their babies. They were physically slighter and weaker than the males. They were only able to have a relatively small number of children during their fertile period. Men were stronger, and there was no real limit to the number of women they could impregnate. We shall examine the implications of sex differences in later chapters, for they are extremely important to the story we are going to tell.
All of this we know with certainty. We know that hominids were familiar with death, of siblings, parents and children. There was disease and injury. The frail or injured were dependent on others for food and protection, otherwise they died. Infant mortality would have been high, life expectancy low.
We can also assume that the savannah grasslands were not a bottomless well of material resources. This Garden of Eden – or rather, the statistical composite of all Edens – was not a land of plenty, with fruit hanging in abundance from every tree and fattened calves meekly waiting to be slaughtered. Finite resources – of prey, edible vegetation, water and shelter – could mean that there was competition for those resources. Not just competition between species, but competition within the species. In other words, we might well have been at war with one another.
Underlying these material facts are some fundamental truths about gene-centred evolution. In the past fifty or so years we have filled in many of the details about how natural selection works, and its logic yields extremely powerful explanations. At the core of the concept is the idea of the ‘selfish’ gene. As we shall see, the selfish gene exerts a massive influence on both the evolutionary development and the existing psychology of the human mind. Not only does it affect our struggle for resources and for mates, it also defines the terms on which our sex lives and family lives evolve.
Most of the assumptions we make rest on evidence that is fragile and inconclusive: deposits of animal and hominid bones and teeth, the remains of stone tools, and the patterns of clustering that show hominid camps, hunting grounds or food-processing areas. It remains to be seen whether we are justified in these predictions of group size and the specifics of eating habits. But we should not underestimate the power of archaeology, because old bones can be extremely rich sources of information.
We are learning more and more about the world in which our human ancestors spent their formative years. It was here that our mind and our instincts evolved, and the conditions on the savannah played a vital role in determining which mental adaptations were allowed through the net of natural selection.
Physical adaptations are relatively easy to spot. The tongue of the bumblebee is perfectly suited to collecting nectar from inside the deep corolla of a flower. Those species of bee with a short tongue, sometimes called ‘nectar robbers’, get around the problem by biting a hole in a petal near the base of the corolla and accessing the nectar that way. Similarly, the wings of most birds are well adapted for the purposes of flapping, swooping and soaring. That is not to say that wings were ‘designed’ to be useful for flying, simply that those birds who inherited genes that coded for more efficient wings were more likely to survive and reproduce. So, in saying that a certain trait ‘X’ is adapted for a certain function ‘Y’, I do not mean to impart any sense of intention or design.
The tongue of a bumblebee or a bird’s wings are each adept at carrying out their allotted tasks. The elegance, symmetry and efficiency of biological adaptations can be seen everywhere in nature. But evolution is not perfect. We should not fall into the trap of thinking that natural selection turns out the best, ‘cheapest’ and most elegant solution to any given problem. Many adaptations appear to be the work of a talented and ingenious biological engineer, but there are also examples that seem rough and ready, badly thought-out, or something of a botched job. Our own eyes are one quite good example. True, they have excellent clarity of vision and colour definition. If they are in prime working order they have a fast autofocus and accurate autoexposure. Additionally, they are self-cleaning and cleverly built into a protective hollow. But we are, many of us, short-sighted,2 and cataracts are common. And there is a major ‘design’ flaw: the light-sensitive retina lies behind a layer of blood vessels and nerves, and these ‘service pipes’ limit the amount of light reaching the retina. This arrangement also necessitates a hole in the retina through which the vessels and nerves can pass to connect with the brain – this hole is our blind spot. And, more seriously, it means the retina can become detached rather easily. It would be much better to have the retina in front, and we can find this superior ‘design’ in large cephalopods such as the squid and octopus.
Evolution is imperfect because it always involves change. The human eye evolved from a patch of light-sensitive cells on the surface of the skin. Once these light-sensitive cells are connected by nerves to the brain and the structural basics of the eye are in place, evolution cannot retrace its steps and completely reorganize the system. The regressive steps would almost certainly never happen.
An added complication is that natural selection encompasses a whole range of simultaneous evolutionary pressures. There is no simple and easy selection for, say, better eyesight without a knock-on effect on another aspect of our person. It may be that the part of the brain used for processing vision uses up power that could have been adapted for some other purpose. No adaptation occurs in isolation, and we are brim-full of compromises and make-do-and-mend.
A good example of this is the malleus and incus, the ‘hammer’ and ‘anvil’, the tiny inner-ear bones which in humans transmit and amplify sound vibrations on their way to the ear drum. These minuscule bones have much in common with the bones found in the lower jaws of reptiles, and in the gills of fish. The similarities are present because mammals, modern reptiles and, indeed, fish inherited these bones from a common ancestor. The difference is that during evolution mammals co-opted the bones for their own purposes. The adaptation is therefore limited by the fact that these bones were once used for something completely different; and in order to get from jaw-bone to ear-bone, it could only take steps that produced a selective advantage for the species concerned. Natural selection cannot simply start again from the ground up and choose the best possible solution. If we were to design a human ear from scratch it would be better for not being a modification of something now obsolete. The passenger flying machine Boeing 747 would have been much less efficient had it been derived from a hot-air balloon.
But for the moment I should simply emphasize that although the human brain may appear to be adapted to perform certain tasks, it does not mean that we are looking at actual adaptations. In animals, especially those whose behaviour seems to consist completely of instinctual responses and processes, deciding whether or not something is an adaptation is a little easier. Both celestial navigation in birds and the labour performed by worker castes of social insects appear to be the results of natural selection, and are thus embedded in the genes. They are both good solutions to extremely complex problems faced during their evolutionary history. The chances of either of these organisms learning their craft from scratch, as we do with reading, are fairly slim. Equally unlikely is that they are the results of so-called ‘genetic drift’, which is essentially a series of random mutations.
The human mind is both more complex and more flexible. We are not slaves to our genes, but we are deeply affected by them. Sorting the adaptations from everything else is extremely difficult. We have to try to filter out the signals of the savannah from the chaotic whirl of human activity. Just because certain types of human behaviour are constant across many different cultures does not mean they are genetically determined. As Daniel Dennett points out, all societies who use spears throw them pointy-end-first, but that does not mean we have a species-wide ‘pointy-end-first’ gene.
When babies open their eyes and begin to register the existence of the outside world, there begins an intricate process of neural development. Instincts get switched on one by one, an array of survival tools that come pre-packaged with a newborn baby.
But the brain cannot develop unless it receives the right stimuli. Susan Greenfield, in her book The Human Brain, describes the case of a six-year-old boy who grew up blind in one eye. Ophthalmologists examined all possible causes of his blindness and could find nothing physically wrong. Then, after reviewing his medical history, it was remembered that as a baby he had had his eye bandaged for two weeks to allow a minor infection to heal. As a result, neural circuits that should have processed the incoming signals from this eye had not developed properly – in fact, they were probably co-opted for another purpose entirely – and therefore the eye was useless.
The environment in which we are brought up is critical for the development of human instinct. This is evident in cases where children have grown up deprived of any human presence. The touching film The Enigma of Kaspar Hauser, made by Werner Herzog in 1975, is based on a true eighteenth-century story of a young man who spent the first years of his life confined in a cell with no human contact. Once he is mysteriously released, to be looked after by the benign villagers who find him, he is discovered to have lost a number of basic instincts such as speech and fear, and he then has to learn them imperfectly to become more human.
‘Feral’ children – children who have grown up in the wild, often nurtured by wolves and other wild animals – provide a cryptic glimpse into human nature. There are few genuine examples of feral children, and none of them has been studied with any rigour or objectivity, but nonetheless they provide us with some limited insight into how the development of human nature depends on the people and culture that surround us.
In 1920, the Reverend J. Singh, the founder of a rural orphanage in India, was told of a ‘Manush-Bagha’, or ‘man-ghost’, in the jungle some miles from his village. This apparition was said to have the body of a human being and the hideous head of a ghost. The reverend’s curiosity was aroused, and he embarked on a trip into the jungle, making sure to take with him a number of armed guards.
They arrived at a huge white ant-mound, as high as a two-storey building. Around it were seven large holes that led to an opening in the centre of the mound. Revd Singh and his party staked out the ant-mound and patiently waited for the arrival of the man-ghost. As dusk was falling, the head of an adult wolf appeared at the opening of one of the holes. It was followed by more wolves and two cubs. Then, crawling after the cubs on all fours, appeared the man-ghost. The body was that of a human child, truly a kind of caveman, the head a big matted ball staring out of which, Singh could see, were piercing eyes.
The man-ghost ran off, still on all fours, into the jungle. Singh decided to come back with men and tools in order to demolish the ant mound and smoke out its inhabitants. As the first spadefuls of earth were carved out of the mound, one of the wolves, an adult female, ran out, and she was shot by one of Singh’s men. As they dug further into the core of the ant-mound they found two cubs and two ‘ghosts’ huddled in a corner who struggled with their captors, baring their teeth, but eventually the men bundled them into sheets and hauled them away.
The ghosts were two young girls, one an infant, their faces almost completely hidden by a wild mass of matted hair. Eventually they became calmer, and Singh was able to feed them raw milk and water. He cut the two girls’ enormous mass of hair, and named them Kamala and Amala. Kamala, he guessed, was around eight years old, and Amala was about eighteen months.
Behaviourally, the two girls were not human, that much was clear. They bore the marks of their life in the wild, and were covered in sores, cuts and boils. Their joints had seized up so they could only move about on all fours; they certainly could not stand up. They appeared to be nocturnal, sleepy during the day and lively and awake at night. Singh reports that their vision appeared to have become adapted to the night, and they had an ability to see in the dark with ease, although on this point he stretches our credulity. They had a taste for raw meat, too. Kamala could smell meat from some distance, and once she was caught eating the entrails of a fowl that had been thrown outside the orphanage compound. They did not use their hands to eat, but instead lowered their mouths to the plate or bowl, like a wolf would do. They showed no signs of communication, and it would be some time before Singh heard them utter a single meaningful sound. They would urinate or defecate anywhere and at any time, and slept entwined together like kittens.
It was not long before the girls, seemingly in need of protection and affection, started to show an attachment towards Singh’s wife. They steadily became more trusting and more playful, but there was still no sign of language, or comprehension of gestures beyond the most basic level.
Less than a year had passed when both girls became seriously ill with dysentery. They were found to be infested with roundworms. They became weaker, and only moved when drink or medicine was brought to their lips. Then, Kamala, the elder of the two girls, showed signs of recovery, but the very next day Amala died. Singh reports that when Amala died, Kamala refused to leave the body. She touched Amala’s face, tried to open her eyelids. Singh says that two tears dropped from her eyes. For the next six days Kamala sat in a corner, alone, unresponsive to affection or touch.
Kamala would sometimes overeat, so much so that she made herself ill. She would not kill animals herself, but if she found carrion she would carry it home, sometimes driving away vultures from the carcass. Occasionally she would hide the carcasses around the orphanage. She also developed a taste for sweets.
Slowly, she began to pick up a few words, like ‘yes’ and the word for ‘dress’, and she knew the names of some of the babies in the orphanage. She understood colours, and became sufficiently acculturated to use the lavatory, at least whenever she thought the Singhs were watching. But she did not progress beyond this. After nine years of living with the Singhs and their foundlings, Kamala fell ill once again, and died.
The wolf-girls of Midnapore could never express themselves beyond communicating the most basic needs. Their story makes clear the fundamental importance of nurture, experience and the social environment in which we are brought up. Our cognitive mechanisms for dealing with the world – whether they are face recognition, language acquisition or emotional development – will not appear of their own accord. Beyond a certain point, it may be too late to ‘switch’ them on.
Just like the development of a child, the process of evolution is intertwined with the growth of culture, and ‘culture’ began well before evolution finally shaped us as we are today. Professor Geertz reminds us that although the invention of the aeroplane has not produced any biological adaptations in humans, that is not necessarily the case for tools invented a couple of million years ago. Stone tools are part of hominid culture, and the simple chopper or flake, invented by Homo habilis, which was made by smashing two rocks together, might have affected the evolution of our opposing thumb, our posture, the size of our teeth and, most importantly, mental capacities like dexterity or spatial reasoning.
It’s tempting to look at our modern lives – our drives, our desires, our hopes, our troubles – and find a nice, simple evolutionary explanation for them all. But we need to be careful. Clifford Geertz proposes that the study of mankind should not entail the simplification of complex explanations. Instead, he says, it should comprise the substitution of simple pictures with complex ones while striving to retain the clarity that went with the simple ones.
Our evolutionary past exerts the most powerful pressure. But the genetic element of human behaviour will always be refracted through the medium of culture. Genes are responsible for the human mind in the same way as a scriptwriter is responsible for a movie. The script forms the basis of the film, but the look and style of the film is determined by the director, designer, editor, and so on. Some of the dialogue will be improvised on set, and occasionally the writer gets fired and the script gets rewritten. And, as my favourite playwright, Luigi Pirandello, might well have observed, each person watching the film may have a different interpretation.
This book is an exploration of the theories and discoveries that populate what is a relatively new area of evolutionary theory. I should perhaps add that it has been written to accompany the television series called Human Instinct and, as I mention in my acknowledgements, is heavily influenced by friends at the BBC who made those programmes and by other, equally talented friends making another series for television, Walking with Cavemen, with which it has been my privilege to be involved.
Nearly all of the best thoughts in this book are, sadly, not mine, but I take full responsibility for any mistakes, failures of interpretation and assumptions. Moreover, many of the most interesting theories are contentious, and some have long provoked outright hostility. But I do hope that this book may shed some small light on what it means to be human, on what it means to be a product of evolution not just physically, but mentally. Instinct, an invisible hand, is ever present in all our lives, and revealing its emotional form may just allow us to understand our real selves a little better.
1 And sometimes, it seems to me from the huge correspondence I get from them, the creationists seem to be protesting so vigorously that they appear as if they are trying to convince themselves.
2 But there is some suggestion that humans are short-sighted in part, at least, as a result of the demands made by being encouraged to read as children. Given that printing has only existed for around eighteen generations, I guess evolution could not have made much impact.