DESMOND MORRIS

The Naked Ape

A Zoologist’s Study of the Human Animal

WITH A FOREWORD BY
Frans de Waal

AND AN INTRODUCTION BY THE AUTHOR

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Copyright © Desmond Morris 1967
Foreword copyright © Frans de Waal 2017
Introduction copyright © Desmond Morris 2017

Desmond Morris has asserted his right to be identified as the author of this Work in accordance with the Copyright, Designs and Patents Act 1988

First published in Great Britain by Jonathan Cape in 1967

This edition reissued by Vintage in 2017

penguin.co.uk/vintage

A CIP catalogue record for this book is available from the British Library

ACKNOWLEDGMENTS

This book is intended for a general audience and authorities have therefore not been quoted in the text. To do so would have broken the flow of words and is a practice suitable only for a more technical work. But many brilliantly original papers and books have been referred to during the assembly of this volume and it would be wrong to present it without acknowledging their valuable assistance. At the end of the book I have included a chapter-by-chapter appendix relating the topics discussed to the major authorities concerned. This appendix is then followed by a selected bibliography giving the detailed references.

I would also like to express my debt and my gratitude to the many colleagues and friends who have helped me, directly and indirectly, in discussions, correspondence and many other ways. They include, in particular, the following: Dr Anthony Ambrose, Sir David Attenborough, Dr David Blest, Dr N. G. Blurton-Jones, Dr John Bowlby, Dr Hilda Bruce, Dr Richard Coss, Dr Richard Davenport, Dr Alisdair Fraser, Professor J. H. Fremlin, Professor Robin Fox, Baroness Jane van Lawick-Goodall, Dr Fae Hall, Professor Sir Alister Hardy, Professor Harry Harlow, Mrs Mary Haynes, Dr Jan van Hooff, Sir Julian Huxley, Miss Devra Kleiman, Dr Paul Leyhausen, Dr Lewis Lipsitt, Mrs Caroline Loizos, Professor Konrad Lorenz, Dr Malcolm Lyall-Watson, Dr Gilbert Manley, Dr Isaac Marks, Mr Tom Maschler, Dr L. Harrison Matthews, Mrs Ramona Morris, Dr John Napier, Mrs Caroline Nicolson, Dr Kenneth Oakley, Dr Frances Reynolds, Dr Vernon Reynolds, The Hon. Miriam Rothschild, Mrs Claire Russell, Dr W. M. S. Russell, Dr George Schaller, Dr John Sparks, Dr Lionel Tiger, Professor Niko Tinbergen, Mr Ronald Webster, Dr Wolfgang Wickler, and Professor John Yudkin.

I hasten to add that the inclusion of a name in this list does not imply that the person concerned necessarily agrees with my views as expressed here in this book.

Finally I would like to thank Professor Frans de Waal for his foreword to this new, fiftieth anniversary edition. As one of the leading figures in primate research today his comments are greatly appreciated.

FOREWORD

Despite explicit warnings – or perhaps precisely because of them – I read The Naked Ape as a young biology student. One of my Dutch professors had pompously declared that there are certain books that no serious scientist would ever touch, because they are intended for a simple-minded public. At the top of his list was this new outrageous book, The Naked Ape, published by Desmond Morris in the UK. It was devoid of any serious content, he said, pulling a disgusted face. I had not yet heard of this book, but the professor’s diatribe made me curious enough to run out and get it. It was so refreshing and irreverent that I have loved it ever since.

This was fifty years ago, in 1967. We are now accustomed to a wide range of popular books about evolution and human behaviour by authors ranging from E. O. Wilson and Richard Dawkins to Steven Pinker and Stephen Jay Gould, not to mention the many books about animal behaviour for lay people, such as my own. But we sometimes forget that this whole trend started with The Naked Ape. No one before had written for a general audience about the latest developments related to human evolution. Books before it had been tame and academic in comparison. The sheer success of Morris’s book, which was translated into 28 languages and sold over 12 million copies, obviously stimulated copycats. Thus, we have seen The Passionate Ape, The Thinking Ape, The Crazy Ape, and a dozen other such titles. But the success of the original has been hard to match, and it is still the only popular biology book that has found its way into the all-time top 100 bestseller list.

Apart from its brilliant title with a tinge of scandal (in those days, ‘naked’ was still a naughty word), the book’s tone was the secret to its success. Morris wrote it in what he has described as ‘four explosive exhausting weeks’, which is an astonishingly short period. The reader catches his breathless spontaneity. The writing is mostly from direct knowledge rather than through the consultation of researched sources. Trained as an ethologist by the Nobel Prize-winning Niko Tinbergen, Morris strikes the right narrative for the odd habits of an animal species that we normally do not even perceive as such. He invites us to look at ourselves through an objective lens, as if we were outsiders, something we have great trouble with. Whereas we prefer to put ourselves on a pedestal, the author – with great humour – keeps us firmly at ground level. In addition, there is the sexually explicit material, the foreplay described in minute detail as part of the courtship of this odd primate about which Morris provocatively notices that ‘he is proud that he has the biggest brain of all the primates, but tries to conceal the fact that he also has the biggest penis’. Some readers may have fainted at all the attention on our mating habits rather than the mental powers that we typically hear about. But this is precisely what gave the book its shock value and success.

It is also a classic in a different, more serious sense. Morris proposed, for example, that human chit-chat serves the same function as primate grooming in maintaining social bonds and togetherness. Decades later, this idea was turned into a serious theory of how evolution replaced grooming with gossip, thus stimulating language evolution. Morris also speculated about pair-bonding as a way to counter a tyrannical alpha male by distributing the females of the tribe equally among its males. This, in turn, was thought to reduce competition to the degree that males could go out hunting together and pool their resources. This idea is still very much alive in anthropology, such as when a few years back the reduced canine teeth of Ardipithecus (a human ancestor from about 4 million years ago) were taken as a sign of peacefulness, which was assumed to imply monogamy.

These evolutionary speculations come straight out of The Naked Ape, but unfortunately the book is rarely credited. It has surely been read, but falls too far outside the scientific mainstream. Our knowledge has grown tremendously in the meantime, such as about the sexual habits of the bonobo (another ape with an impressive penis), or the various ways co-operation and altruism may have evolved. We cannot hold it against a half-century-old book that it doesn’t represent the latest knowledge. But it is still very much worth reading, because its main strength is not so much in its data and theories, but rather the line of thought that is being followed. Morris thinks like an evolutionary biologist, who seeks to explain human behaviour based on how it contributes to survival and reproduction. He presents the curious social and sexual habits of our species as a series of problems that any biologist would like to solve, such as questions about the origin of our nakedness and upright gait, of homosexuality, of the female orgasm, or the role of playfulness in art and culture. All of these issues are still very much being debated today. It is this pattern of thought, rather than the conclusions drawn, that make the book such an exciting read.

Rereading it today, I hardly notice the emphasis on nature over nurture, such as when the author reflects on biological sex differences. This is because the power of biology has become a non-issue: it is nowadays taken for granted. But remember that at the time when The Naked Ape came out we were not allowed to propose that genes influence human behaviour or that our sexuality shapes society rather than the other way around. Humanity was considered its own creation. Culture is what makes us human, is how it was put, and genetics were entirely kept out of the debate. Breaking this taboo was an obvious step for a biologist such as Morris, and was no doubt the greatest contribution of The Naked Ape. It poked a big hole in the idea that humans start their lives as blank slates. The author’s tongue-in-cheek style took the sting out of what at the time was a hugely sensitive topic, and its success showed once and for all that people were ready to ponder their lives in an evolutionary light.

Frans de Waal, 2017

Frans de Waal, a primatologist and professor at Emory University in Atlanta, is the author of many popular books, including: Are We Smart Enough to Know How Smart Animals Are? (Norton/Granta, 2016).

INTRODUCTION BY THE AUTHOR

I find it hard to believe that half a century has passed since The Naked Ape was first published. I find it even harder to believe that, in my ninetieth year, I am still here to enjoy celebrating its 50th anniversary.

What was it about this book that produced such a strong reaction? First, it was considered to be shocking and, with books, a little audacity goes a long way. For me, of course, it was not shocking at all. I was simply telling the truth about human beings as I saw it. As a zoologist who had spent years studying the behaviour of other animals, it was only a short step to consider the behaviour of that unusual primate species Homo sapiens. I decided to focus on those aspects of behaviour that we share with other animals and it is no accident that the titles of the chapters in my doctoral thesis about a small fish were much the same as those in The Naked Ape. To emphasise my zoological approach I gave our species a new name – the sort of title that would have been given by a zoologist from another world who landed here and surveyed the many life forms on this small planet.

From this starting point I set out to tell the blunt truth, as I saw it, about the conduct of this remarkably successful animal. Some critics said it was demeaning to discuss humans as animals, but for me, it was a case of elevating the human animal to the level of those other species that I cared so much about and had spent most of my life investigating. As a child growing up during the Second World War, I had taken a poor view of adult humans who seemed to be obsessed with killing one another. In a school essay I described human beings as ‘monkeys with diseased brains’. As an escape from the horror of so-called civilisation, I turned to other species and became a fanatical animal-watcher, more fascinated by toads and snakes and foxes than men with guns and bombs. It was the war that turned me into a zoologist and it took me many years to accept that, after all, human beings did have some special qualities that were worthy of study. When they were not torturing, slaughtering or terrorising one another, they did, indeed, have some rather exciting animal qualities. Sexually they were in a league of their own, their parental care was second to none, and their play patterns exceeded anything found elsewhere in the animal kingdom. I started to warm to them.

From my early studies of fish, I had moved on to birds and then to mammals, culminating in a long study of chimpanzees. Humans were logically the next step, and I began to collect information about their evolution and their behaviour. When I was ready, I took a month’s leave from my busy life as curator of mammals at the Zoological Society in London and started writing day and night until, just before the four weeks was up, I had completed the 80,000 words that were needed. My first draft was my last draft and I put the sheets in a folder and took it to a party my publisher was giving at a bookshop. There was no carbon copy and when he put the folder up onto a bookshelf I was worried that perhaps it might be lost or forgotten. Happily, he took it home with him and read it over Christmas.

When it appeared in October 1967 I found myself under attack from three main quarters. The first attack came from academics who said that the book lacked references, footnotes and even an index. All these omission were deliberate. I wanted to speak directly to a general audience, not display erudition to impress other academics. I had been playing the academic game for years, but I had tired of that, having realised that so much of it was a status display by scientists whose prose was almost unreadable. They had forgotten the need to communicate and were involved instead in an in-game that had more to do with academic rivalries than the dissemination of ideas. All I wanted to do was to tell people how I viewed the human species and so I wrote in the simplest, most accessible form of language, as though I were chatting to someone rather than lecturing them. And I still make no apology for this.

The second attack came from those who said that my book was insulting to religion. Viewing man as a risen ape rather than a fallen angel had caused offence. On one occasion, when I was appearing on television defending the book, I was confronted by a bishop who asked me if I thought that a human being had a soul. Having noticed that devious politicians always answer a difficult question with a counter-question, I asked him if he thought that a chimpanzee had a soul. I could see from his body language that this question had upset him because he knew that, if he said that the ape did have a soul, this would upset his more traditional followers who considered that all animals, as the Bible tells us, are ‘brute beasts of no understanding’. On the other hand, if he said that the ape did not have a soul, this would upset those among his flock who also happened to be devout animal-lovers. So he was in a dilemma. But you do not get to be a bishop without acquiring some of the verbal skills of silky diplomats, so after a long pause he replied that in his opinion, the chimpanzee had a very small soul. To which I responded by saying that, in that case, I considered that man was a very great animal.

The truth was that I did not want to become side-tracked into a debate about religious beliefs. My book was about the way people behave, about the way they act, not the way they think. In the text I described the kind of activities that religious people perform and explained their value to the group. But this did not stop the pious from pursuing me.

The third attack came from those whose professional territories I had so rudely invaded. I was a zoologist and had no right, it seemed, to intrude into the specialist worlds of anthropology, psychology and sociology. At the time I was writing, back in the 1960s, the main theme of those studies was that everything human beings do is purely learnt behaviour and has nothing to do with our ancient ancestry or our genetic inheritance. Here was I, saying that our genes not only influenced the colour of our eyes, and our other anatomical features, but that they also played a part in determining how we behaved. This, they felt, was outrageous. However, if, like me, they had studied the behaviour of a variety of different species, they would have known that every animal benefits from inherited patterns of behaviour and I could see no reason why the human species should be any different. True, we are remarkably flexible and innovative, compared with other species, but even that quality is something that we inherit. It is an extension of the childhood playfulness that we share with other animals, but which we prolong into adult life where it becomes more serious and where we give it new names, such as artistic creativity or scientific inventiveness.

Since the day when The Naked Ape was published in 1967 I have watched with quiet amusement the way in which the influence of genetic factors on human behaviour has become more and more accepted in the scientific world. It is now widely recognised that we are programmed at birth with a set of genetic suggestions as to how we should behave if we are to enjoy a fulfilled life. We can be trained to diverge from these suggested pathways, but if we do so we are liable to suffer from a variety of frustrations and mental disturbances, because these new ways of conducting our day-to-day living do not suit the biological personality of our species.

You will have noticed that I have used the phrase genetic suggestions, rather than genetic instructions. This is because these influences are not rigid and we can bend them slightly this way or that without causing too much damage. It is only when we diverge strongly from our ancient patterns of behaviour that the trouble arises. When I was writing The Naked Ape I was trying to say, this is the way human beings evolved and these are our natural, animal qualities. They are extraordinary and we are extraordinary animals. To me, this is not a demeaning message, it is liberating and, speaking personally, I have been able to live my long life without wasting too much of it on aberrant activities that are alien to the human temperament.

Desmond Morris, 2017

INTRODUCTION

There are one hundred and ninety-three living species of monkeys and apes. One hundred and ninety-two of them are covered with hair. The exception is a naked ape self-named Homo sapiens. This unusual and highly successful species spends a great deal of time examining his higher motives and an equal amount of time studiously ignoring his fundamental ones. He is proud that he has the biggest brain of all the primates, but attempts to conceal the fact that he also has the biggest penis, preferring to accord this honour falsely to the mighty gorilla. He is an intensely vocal, acutely exploratory, overcrowded ape, and it is high time we examined his basic behaviour.

I am a zoologist and the naked ape is an animal. He is therefore fair game for my pen and I refuse to avoid him any longer simply because some of his behaviour patterns are rather complex and impressive. My excuse is that, in becoming so erudite, Homo sapiens has remained a naked ape nevertheless; in acquiring lofty new motives, he has lost none of the earthy old ones. This is frequently a cause of some embarrassment to him, but his old impulses have been with him for millions of years, his new ones only a few thousand at the most – and there is no hope of quickly shrugging off the accumulated genetic legacy of his whole evolutionary past. He would be a far less worried and more fulfilled animal if only he would face up to this fact. Perhaps this is where the zoologist can help.

One of the strangest features of previous studies of naked-ape behaviour is that they have nearly always avoided the obvious. The earlier anthropologists rushed off to all kinds of unlikely corners of the world in order to unravel the basic truth about our nature, scattering to remote cultural backwaters so atypical and unsuccessful that they are nearly extinct. They then returned with startling facts about the bizarre mating customs, strange kinship systems, or weird ritual procedures of these tribes, and used this material as though it were of central importance to the behaviour of our species as a whole. The work done by these investigators was, of course, extremely interesting and most valuable in showing us what can happen when a group of naked apes becomes side-tracked into a cultural blind alley. It revealed just how far from the normal our behaviour patterns can stray without a complete social collapse. What it did not tell us was anything about the typical behaviour of typical naked apes. This can only be done by examining the common behaviour patterns that are shared by all the ordinary, successful members of the major cultures – the mainstream specimens who together represent the vast majority. Biologically, this is the only sound approach. Against this, the old-style anthropologist would have argued that his technologically simple tribal groups are nearer the heart of the matter than the members of advanced civilizations. I submit that this is not so. The simple tribal groups that are living today are not primitive, they are stultified. Truly primitive tribes have not existed for thousands of years. The naked ape is essentially an exploratory species and any society that has failed to advance has in some sense failed, ‘gone wrong’. Something has happened to it to hold it back, something that is working against the natural tendencies of the species to explore and investigate the world around it. The characteristics that the earlier anthropologists studied in these tribes may well be the very features that have interfered with the progress of the groups concerned. It is therefore dangerous to use this information as the basis for any general scheme of our behaviour as a species.

Psychiatrists and psychoanalysts, by contrast, have stayed nearer home and have concentrated on clinical studies of mainstream specimens. Much of their earlier material, although not suffering from the weakness of the anthropological information, also has an unfortunate bias. The individuals on which they have based their pronouncements are, despite their mainstream background, inevitably aberrant or failed specimens in some respect. If they were healthy, successful and therefore typical individuals, they would not have had to seek psychiatric aid and would not have contributed to the psychiatrists’ store of information. Again, I do not wish to belittle the value of this research. It has given us an immensely important insight into the way in which our behaviour patterns can break down. I simply feel that in attempting to discuss the fundamental biological nature of our species as a whole, it is unwise to place too great an emphasis on the earlier anthropological and psychiatric findings.

(I should add that the situation in anthropology and psychiatry is changing rapidly. Many modern research workers in these fields are recognizing the limitations of the earlier investigations and are turning more and more to studies of typical, healthy individuals. As one investigator expressed it recently: ‘We have put the cart before the horse. We have tackled the abnormals and we are only now beginning, a little late in the day, to concentrate on the normals.’)

The approach I propose to use in this book draws its material from three main sources: (1) the information about our past as unearthed by palaeontologists and based on the fossil and other remains of our ancient ancestors; (2) the information available from the animal behaviour studies of the comparative ethologists, based on detailed observations of a wide range of animal species, especially our closest living relatives, the monkeys and apes; and (3) the information that can be assembled by simple, direct observation of the most basic and widely shared behaviour patterns of the successful mainstream specimens from the major contemporary cultures of the naked ape itself.

Because of the size of the task, it will be necessary to oversimplify in some manner. The way I shall do this is largely to ignore the detailed ramifications of technology and verbalization, and concentrate instead on those aspects of our lives that have obvious counterparts in other species: such activities as feeding, grooming, sleeping, fighting, mating and care of the young. When faced with these fundamental problems, how does the naked ape react? How do his reactions compare with those of other monkeys and apes? In which particular respect is he unique, and how do his oddities relate to his special evolutionary story?

In dealing with these problems I realize that I shall run the risk of offending a number of people. There are some who will prefer not to contemplate their animal selves. They may consider that I have degraded our species by discussing it in crude animal terms. I can only assure them that this is not my intention. There are others who will resent any zoological invasion of their specialist arena. But I believe that this approach can be of great value and that, whatever its shortcomings, it will throw new (and in some ways unexpected) light on the complex nature of our extraordinary species.

1. ORIGINS

There is a label on a cage at a certain zoo that states simply, ‘This animal is new to science’. Inside the cage there sits a small squirrel. It has black feet and it comes from Africa. No black-footed squirrel has ever been found in that continent before. Nothing is known about it. It has no name.

For the zoologist it presents an immediate challenge. What is it about its way of life that has made it unique? How does it differ from the three hundred and sixty-six other living species of squirrels already known and described? Somehow, at some point in the evolution of the squirrel family, the ancestors of this animal must have split off from the rest and established themselves as an independent breeding population. What was it in the environment that made possible their isolation as a new form of life? The new trend must have started out in a small way, with a group of squirrels in one area becoming slightly changed and better adapted to the particular conditions there. But at this stage they would still be able to inter-breed with their relatives nearby. The new form would be at a slight advantage in its special region, but it would be no more than a race of the basic species and could be swamped out, reabsorbed into the mainstream at any point. If, as time passed, the new squirrels became more and more perfectly tuned in to their particular environment, the moment would eventually arrive when it would be advantageous for them to become isolated from possible contamination by their neighbours. At this stage their social and sexual behaviour would undergo special modifications, making inter-breeding with other kinds of squirrels unlikely and eventually impossible. At first, their anatomy may have changed and become better at coping with the special food of the district, but later their mating calls and displays would also differ, ensuring that they attracted only mates of the new type. At last, a new species would have evolved, separate and discrete, a unique form of life, a three hundred and sixty-seventh kind of squirrel.

When we look at our unidentified squirrel in its zoo cage, we can only guess about these things. All we can be certain about is that the markings of its fur – its black feet – indicate that it is a new form. But these are only the symptoms, the rash that gives a doctor a clue about his patient’s disease. To really understand this new species, we must use these clues only as a starting point, telling us there is something worth pursuing. We might try to guess at the animal’s history, but that would be presumptuous and dangerous. Instead we will start humbly by giving it a simple and obvious label: we will call it the African black-footed squirrel. Now we must observe and record every aspect of its behaviour and structure and see how it differs from, or is similar to, other squirrels. Then, little by little, we can piece together its story.

The great advantage we have when studying such animals is that we ourselves are not black-footed squirrels – a fact which forces us into an attitude of humility that is becoming to proper scientific investigation. How different things are, how depressingly different, when we attempt to study the human animal. Even for the zoologist, who is used to calling an animal an animal, it is difficult to avoid the arrogance of subjective involvement. We can try to overcome this to some extent by deliberately and rather coyly approaching the human being as if he were another species, a strange form of life on the dissecting table, awaiting analysis. How can we begin?

As with the new squirrel, we can start by comparing him with other species that appear to be most closely related. From his teeth, his hands, his eyes and various other anatomical features, he is obviously a primate of some sort, but of a very odd kind. Just how odd becomes clear when we lay out in a long row the skins of the one hundred and ninety-two living species of monkeys and apes, and then try to insert a human pelt at a suitable point somewhere in this long series. Wherever we put it, it looks out of place. Eventually we are driven to position it right at one end of the row of skins, next to the hides of the tailless great apes such as the chimpanzee and the gorilla. Even here it is obtrusively different. The legs are too long, the arms are too short and the feet are rather strange. Clearly this species of primate has developed a special kind of locomotion which has modified its basic form. But there is another characteristic that cries out for attention: the skin is virtually naked. Except for conspicuous tufts of hair on the head, in the armpits and around the genitals, the skin surface is completely exposed. When compared with the other primate species, the contrast is dramatic. True, some species of monkeys and apes have small naked patches of skin on their rumps, their faces, or their chests, but nowhere amongst the other one hundred and ninety-two species is there anything even approaching the human condition. At this point and without further investigation, it is justifiable to name this new species the ‘naked ape’. It is a simple, descriptive name based on a simple observation, and it makes no special assumptions. Perhaps it will help us to keep a sense of proportion and maintain our objectivity.

Staring at this strange specimen and puzzling over the significance of its unique features, the zoologist now has to start making comparisons. Where else is nudity at a premium? The other primates are no help, so it means looking further afield. A rapid survey of the whole range of the living mammals soon proves that they are remarkably attached to their protective, furry covering, and that very few of the 4,237 species in existence have seen fit to abandon it. Unlike their reptilian ancestors, mammals have acquired the great physiological advantage of being able to maintain a constant, high body temperature. This keeps the delicate machinery of the body processes tuned in for top performance. It is not a property to be endangered or discarded lightly. The temperature-controlling devices are of vital importance and the possession of a thick, hairy, insulating coat obviously plays a major role in preventing heat loss. In intense sunlight it will also prevent over-heating and damage to the skin from direct exposure to the sun’s rays. If the hair has to go, then clearly there must be a very powerful reason for abolishing it. With few exceptions this drastic step has been taken only when mammals have launched themselves into an entirely new medium. The flying mammals, the bats, have been forced to denude their wings, but they have retained their furriness elsewhere and can hardly be counted as naked species. The burrowing mammals have in a few cases – the naked mole rat, the aardvark and the armadillo, for example – reduced their hairy covering. The aquatic mammals such as the whales, dolphins, porpoises, dugongs, manatees and hippopotamuses have also gone naked as part of a general streamlining. But for all the more typical surface-dwelling mammals, whether scampering about on the ground or clambering around in the vegetation, a densely hairy hide is the basic rule. Apart from those abnormally heavy giants, the rhinos and the elephants (which have heating and cooling problems peculiar to themselves), the naked ape stands alone, marked off by his nudity from all the thousands of hairy, shaggy or furry land-dwelling mammalian species.

At this point the zoologist is forced to the conclusion that either he is dealing with a burrowing or an aquatic mammal, or there is something very odd, indeed unique, about the evolutionary history of the naked ape. Before setting out on a field trip to observe the animal in its present-day form, the first thing to do, then, is to dig back into its past and examine as closely as possible its immediate ancestors. Perhaps by examining the fossils and other remains and by taking a look at the closest living relatives, we shall be able to gain some sort of picture of what happened as this new type of primate emerged and diverged from the family stock.

It would take too long to present here all the tiny fragments of evidence that have been painstakingly collected over the past century. Instead, we will assume that this task has been done and simply summarize the conclusions that can be drawn from it, combining the information available from the work of the fossil-hungry palaeontologists with the facts gathered by the patient ape-watching ethologists.

The primate group, to which our naked ape belongs, arose originally from primitive insectivore stock. These early mammals were small, insignificant creatures, scuttling nervously around in the safety of the forests, while the reptile overlords were dominating the animal scene. Between eighty and fifty million years ago, following the collapse of the great age of reptiles, these little insect-eaters began to venture out into new territories. There they spread and grew into many strange shapes. Some became plant-eaters and burrowed under the ground for safety, or grew long, stilt-like legs with which to flee from their enemies. Others became long-clawed, sharp-toothed killers. Although the major reptiles had abdicated and left the scene, the open country was once again a battlefield.

Meanwhile, in the undergrowth, small feet were still clinging to the security of the forest vegetation. Progress was being made here, too. The early insect-eaters began to broaden their diet and conquer the digestive problems of devouring fruits, nuts, berries, buds and leaves. As they evolved into the lowliest forms of primates, their vision improved, the eyes coming forward to the front of the face and the hands developing as food-graspers. With three-dimensional vision, manipulating limbs and slowly enlarging brains, they came more and more to dominate their arboreal world.

Somewhere between twenty-five and thirty-five million years ago, these pre-monkeys had already started to evolve into monkeys proper. They were beginning to develop long, balancing tails and were increasing considerably in body size. Some were on their way to becoming leaf-eating specialists, but most were keeping to a broad, mixed diet. As time passed, some of these monkey-like creatures became bigger and heavier. Instead of scampering and leaping they switched to brachiating – swinging hand over hand along the underside of the branches. Their tails became obsolete. Their size, although making them more cumbersome in the trees, made them less wary of ground-level sorties.

Even so, at this stage – the ape phase – there was much to be said for keeping to the lush comfort and easy pickings of their forest of Eden. Only if the environment gave them a rude shove into the great open spaces would they be likely to move. Unlike the early mammalian explorers, they had become specialized in forest existence. Millions of years of development had gone into perfecting this forest aristocracy, and if they left now they would have to compete with the (by this time) highly advanced ground-living herbivores and killers. And so there they stayed, munching their fruit and quietly minding their own business.

It should be stressed that this ape trend was for some reason taking place only in the Old World. Monkeys had evolved separately as advanced tree-dwellers in both the Old and the New World, but the American branch of the primates never made the ape grade. In the Old World, on the other hand, ancestral apes were spreading over a wide forest area from western Africa, at one extreme, to south-eastern Asia at the other. Today the remnants of this development can be seen in the African chimpanzees and gorillas and the Asian gibbons and orangutans. Between these two extremities the world is now devoid of hairy apes. The lush forests have gone.

What happened to the early apes? We know that the climate began to work against them and that, by a point somewhere around fifteen million years ago, their forest strongholds had become seriously reduced in size. The ancestral apes were forced to do one of two things: either they had to cling on to what was left of their old forest homes, or, in an almost biblical sense, they had to face expulsion from the Garden. The ancestors of the chimpanzees, gorillas, gibbons and orangs stayed put, and their numbers have been slowly dwindling ever since. The ancestors of the only other surviving ape – the naked ape – struck out, left the forests, and threw themselves into competition with the already efficiently adapted ground-dwellers. It was a risky business, but in terms of evolutionary success it paid dividends.

The naked ape’s success story from this point on is well known, but a brief summary will help, because it is vital to keep in mind the events which followed if we are to gain an objective understanding of the present-day behaviour of the species.

Faced with a new environment, our ancestors encountered a bleak prospect. They had to become either better killers than the old-time carnivores, or better grazers than the old-time herbivores. We know today that, in a sense, success has been won on both scores; but agriculture is only a few thousand years old, and we are dealing in millions of years. Specialized exploitation of the plant life of the open country was beyond the capacity of our early ancestors and had to await the development of advanced techniques of modern times. The digestive system necessary for a direct conquest of the grassland food supply was lacking. The fruit and nut diet of the forest could be adapted to a root and bulb diet at ground level, but the limitations were severe. Instead of lazily reaching out to the end of the branch for a luscious ripe fruit, the vegetable-seeking ground ape would be forced to scratch and scrape painstakingly in the hard earth for his precious food.

His old forest diet, however, was not all fruit and nut. Animal proteins were undoubtedly of great importance to him. He came originally, after all, from basic insectivore stock, and his ancient arboreal home had always been rich in insect life. Juicy bugs, eggs, young helpless nestlings, tree-frogs and small reptiles were all grist to his mill. What is more, they posed no great problems for his rather generalized digestive system. Down on the ground this source of food supply was by no means absent and there was nothing to stop him increasing this part of his diet. At first, he was no match for the professional killer of the carnivore world. Even a small mongoose, not to mention a big cat, could beat him to the kill. But young animals of all kinds, helpless ones or sick ones, were there for the taking, and the first step on the road to major meat-eating was an easy one. The really big prizes, however, were poised on long, stilt-like legs, ready to flee at a moment’s notice at quite impossible speeds. The protein-laden ungulates were beyond his grasp.

This brings us to the last million or so years of the naked ape’s ancestral history, and to a series of shattering and increasingly dramatic developments. Several things happened together, and it is important to realize this. All too often, when the story is told, the separate parts of it are spread out as if one major advance led to another, but this is misleading. The ancestral ground apes already had large and high-quality brains. They had good eyes and efficient grasping hands. They inevitably, as primates, had some degree of social organization. With strong pressure on them to increase their prey-killing prowess, vital changes began to take place. They became more upright – fast, better runners. Their hands became freed from locomotion duties – strong, efficient weapon-holders. Their brains became more complex – brighter, quicker decision-makers. These things did not follow one another in a major, set sequence; they blossomed together, minute advances being made first in one quality and then in another, each urging the other on. A hunting ape, a killer ape, was in the making.

It could be argued that evolution might have favoured the less drastic step of developing a more typical cat- or dog-like killer, a kind of cat-ape or dog-ape, by the simple process of enlarging the teeth and nails into savage fang-like and claw-like weapons. But this would have put the ancestral ground ape into direct competition with the already highly specialized cat and dog killers. It would have meant competing with them on their own terms, and the outcome would no doubt have been disastrous for the primates in question. (For all we know, this may actually have been tried and failed so badly that the evidence has not been found.) Instead, an entirely new approach was made, using artificial weapons instead of natural ones, and it worked.

From tool-using to tool-making was the next step, and alongside this development went improved hunting techniques, not only in terms of weapons, but also in terms of social co-operation. The hunting apes were pack-hunters, and as their techniques of killing were improved, so were their methods of social organization. Wolves in a pack deploy themselves, but the hunting ape already had a much better brain than a wolf and could turn it to such problems as group communication and co-operation. Increasingly complex manoeuvres could be developed. The growth of the brain surged on.

Essentially this was a hunting group of males. The females were too busy rearing the young to be able to play a major role in chasing and catching prey. As the complexity of the hunt increased and the forays became more prolonged, it became essential for the hunting ape to abandon the meandering, nomadic ways of its ancestors. A home base was necessary, a place to come back to with the spoils, where the females and young would be waiting and could share the food. This step, as we shall see in later chapters, has had profound effects on many aspects of the behaviour of even the most sophisticated naked apes of today.

So the hunting ape became a territorial ape. His whole sexual, parental and social pattern began to be affected. His old wandering, fruit-plucking way of life was fading rapidly. He had now really left his forest of Eden. He was an ape with responsibilities. He began to worry about the prehistoric equivalent of washing machines and refrigerators. He began to develop the home comforts – fire, food storage, artificial shelters. But this is where we must stop for the moment, for we are moving out of the realms of biology and into the realms of culture. The biological basis of these advanced steps lies in the development of a brain large and complex enough to enable the hunting ape to take them, but the exact form they assume is no longer a matter of specific genetic control. The forest ape that became a ground ape that became a hunting ape that became a territorial ape has become a cultural ape, and we must call a temporary halt.

It is worth reiterating here that, in this book, we are not concerned with the massive cultural explosions that followed, of which the naked ape of today is so proud – the dramatic progression that led him, in a mere half-million years, from making a fire to making a space-craft. It is an exciting story, but the naked ape is in danger of being dazzled by it all and forgetting that beneath the surface gloss he is still very much a primate. (‘An ape’s an ape, a varlet’s a varlet, though they be clad in silk or scarlet.’) Even a space ape must urinate.

Only by taking a hard look at the way in which we have originated and then by studying the biological aspects of the way we behave as a species today can we really acquire a balanced, objective understanding of our extraordinary existence.