Early Humans and Their World

Bo Gräslund

• Publisher: Routledge
• Year: 2005
• Print ISBN: 9780415353441
• eBook ISBN: 9781134261345
• Topic: History
• Subtopic: Ancient History
• Index: History

Summarizing modern research on early hominid evolution from the apes six million years ago to the emergence of modern humans, this book is the first to present a synthetic discussion of many aspects of early human life.

1
THE TANGIBLE PAST

Time perspectives

Every breath we draw, every step we take, every emotion we experience reflects our past. As the youngest link in an evolutionary chain many hundreds of millions of years old, every person is a wandering exhibition of her or his biological history.

This insight presses itself upon us unlooked for when we study a subject such as the evolution of the human race. This prompts me to begin this book with a few reflections on humanitys evolutionary background.

To make an open-minded journey through the past is an exhilarating experience, worth any amount of effort. But there are also other reasons to listen to what has gone before. All over the world those in power demonstrate their ignorance of history. To the extent that they have a historical perspective at all, it is often so narrow that it mostly tempts them to abuse the past. Unless we take a long view of the past, then we will never be able to think more than a few years into the future – at best a few generations, rarely the necessary centuries, millennia and millions of years. Never before has it been so important to place the present and future in a larger temporal context.

Our ancestors living in more traditional social patterns had close emotional and cultural relationships to their past. Now those connections are mostly passive in the sense that they are maintained by a few experts on behalf of the majority. For most people today, the past appears to them as an abyss.

During the long period when the human brain evolved to what it is today, there was hardly any evolutionary need for reflection on a broad spatial, social and temporal scale. Humanity’s natural understanding of time and social space has thereby become ever more confined to the narrow horizon of the individual’s own lifetime. To this we can add our difficulty in imagining that which we cannot relate to our own experience. The ability to think farsightedly into the future does not seem prominent among our gifts.

Many people experience the time reckoning of history books – years, millennia and millions of years – as abstractions, almost as difficult to grasp as the distances of inter-stellar space. With this in mind, let us try to find a more concrete measurement of time. Human beings generally produce about three generations every hundred years. Instead of placing Genghis Khan about 800 years ago, we can say that he lived about 24 generations before the present. Twenty-four people: about the size of a school class. So we can use the timescale of parents plus children, or parents plus children and grandchildren, family units with which most people are well familiar. At once the distance shrinks to 12 two-generation or 8 three-generation families in straight descent. It doesn’t sound very much, and the point is that it isn’t.

Consider the fact that only 60 or so generations of people or 20 three-generation families separates us from the time of Jesus Christ; that the Stone Age in northern Europe lasted until 135 generations or 45 three-generation families ago; that my home country of Sweden has not even been populated for more than 400 generations or 133 three-generation families; and that what we call civilisation began as late as 350 generations ago.

On the other hand, biologically modern humans have more than 6,000 generations behind them, and our ancestors have been walking upright for something approaching 250,000 generations.

Talking about time in this way brings the past closer, and the present into focus. It lets us understand that our history and culture are not very old at all, and that in some sense the threads that bind us to the past are very short.

Ever since we began to till the soil, keep domestic animals and live in settled communities, some 350 generations ago, we can see how population pressure and economic growth have been instrumental in the drive for technological, cultural and social development. Today the global society is as dependent on growth as an addict on a drug. As long as the growth mechanisms function then most things eventually get sorted out, but as soon as expansion stagnates or is reversed then society is shaken to its foundations. In this way the concept of growth has come to stand for progress and positive development to the point at which it has superseded all other ideologies, including those of religion.

The Western understanding of history is saturated by the notion that evolution has led from lower forms of culture and society to ever-greater heights of civilisation. The more developed is seen as automatically superior to the less developed, and the past as inferior to the present. Despite the fact that our belief in the future has become somewhat ragged around the edges, the devaluation of the past is still etched firmly in the popular consciousness. Not many would be attracted by the idea of time-travelling 10,000, 20,000 or 100,000 years back into history, at least not on a one-way ticket.

With an evolutionary weakness that makes it hard for us to deal with the future, we allow short-term problems to overshadow those of the long-term. Our globe has finally become a crawling ant-heap which every hour adds another 100,000 people to its population. While only a small proportion of this mass of humanity enjoys anything approaching adequate welfare, the earth’s resources are still being depleted, its diversity of plant and animal life is being reduced, and the environmental conditions for life are declining rapidly.

The history of our civilisation has thrown up many examples of enlightened cultural efforts, impressive social achievements and individual human greatness. But all the while this picture is dimmed by a collective stupidity and shallowness of truly appalling dimensions. This is a paradox that is only intelligible in the light of a very long evolutionary perspective. However, to blame our ancestors for all this would be meaningless. The paths of history have been marked by combinations of cultural, social, biological and environmental factors that neither individuals nor groups have ever before been able to perceive, understand or control. In fact it is possible that humans like us may never actually acquire this talent, as our intelligence has inherited limitations which impair our ability to survey, analyse and counteract the long-term effects of our collective activities.

For the greater part of humanity’s time on earth, cultural change has proceeded at a snail’s pace, to such a degree that even relatively recent generations of modern humans must have understood the world as essentially static. The winds of change have now become a hurricane. In the short space of a human life a person can now experience greater technological and social evolution than once occurred over thousands of generations.

As a norm for a good society, most people would probably put forward notions such as democracy and welfare for all, a high material standard, comfort, good health, good medical care, a long lifespan, and good food and drink, not forgetting the joys of culture and sport. The problem is that this vision has not so far been reconciled with another, equally self-evident dream: a world without hunger, epidemics and ruined environments, a life without war, violence, torture, sexual assault, oppression, stress, anxiety and loneliness.

We have had to take the bad with the good. Both of these aspects of reality in fact derive primarily from the effects of one and the same event – the moment when we became settled, socialising farmers. This process began as late as 350 generations ago in the Near East and Asia, and 180 generations ago in Central America. But the modern human is infinitely older. As far as we know at present, about 6,000 generations have passed since we emerged in Africa; in the Near East we appeared 3,000 generations ago; in Australia, 2,000; in Europe, 1,500; and in America some 500 to 1,000 generations have elapsed.

For a species with such a sluggish cycle of generation, evolution works slowly. There is nothing to suggest that the people of late prehistory were in any way intellectually or neurologically different from you or me. In other words, the modern human is not modern at all. We are children of the early Stone Age.

This means that in the essentials we evolved for a quite different environment than that of the industrialised world, which is just a few moments old.

In evolutionary terms, we are therefore poorly equipped to meet many of the demands placed upon us by a modern society. There is no doubt that many of our current and historical problems – social, psychological, medical and political – stem from this imbalance between inherited qualities and needs, and cultural development. A lack of insight and knowledge of this permanent opposition is a threat to the future of humanity. This is one of several reasons to improve our acquaintance with the evolutionary history of our species.

Family ties

Although all living organisms are perhaps not related at the cellular level, they nevertheless belong on the same family tree. In this sense we have a collective inheritance with insects, plants and bacteria. We in fact share something like 40 per cent of our genes with a relative as far removed as the banana. To some animals we stand very close indeed.

Even so, we are keener to speak of what separates us from other creatures than of what unites us with them. We prefer to think in terms of ‘us’ and ‘others’, and it is only rarely that our comparisons favour the animals. The feeling of communality and humility in relation to animals, nature and the rhythm of life, which characterised more traditional societies, was slowly transformed into its opposite through the population pressure of agrarian subsistence and its need for control over the environment. From this arose the notion that human beings stood higher than other creatures, made ruler over ‘the beasts of the field and the fowls of the heavens’.

To define the modern human as a species is not problematic. But when did we actually become people? Is it possible to find some point in the chain of evolution when our animal ancestors became . . . us? This question cannot be answered at a stroke, because the more we learn about animals the more indistinct this border becomes.

For many years the only true criteria for increasing ‘human-ness’ were defined in terms of culture, as expressed in the manufacture and use of tools. However, we now know that even common chimpanzees in the wild deliberately prepare and employ tools, and to some extent teach these skills to their young. They can also treat stone objects in such a way that the resulting debitage differs only in the most minor ways from the earliest finds of stone tools made by humans. Their tools and even their way of using them are also culturally variable. Many other animals also use tools. In the same way, many other animals have a discernible intelligence, a considerable ability to understand concepts, an elementary capacity for abstraction and a basic consciousness of personality. We are unique in having an articulated, complex language, but we are not alone in possessing a functioning communication system. The problem is that opinions differ considerably as to when this level of complex language was achieved.

It has sometimes been suggested that the real watershed between animals and humans came into being when our ancestors began to overcome self-interest with regard to those who were not their close relatives, for example by dividing food equally within a group. Unfortunately we have only the slightest grasp of when this could have been and when a truly human altruism began to emerge. Naturally, this kind of behaviour is not easy to recover archaeologically. As an aside we can note that our close relatives in the wild, such as chimpanzees and some groups of orang-utans, also share their food, albeit unsystematically.

Researchers with a more pessimistic view of human nature have argued that we are at least unique in our ability to wage war against our own species. However, we are forced to share even this miserable claim with others, at least with common chimpanzees and some social insects, such as certain kinds of ants.

When so many differences between animals and modern humans are more a matter of degree than outright opposites, it is not strange that we should find it so hard to isolate signals of a true humanity that would separate the earliest hominids from their closest ancestors among the contemporary apes. Time and again we have been forced to retreat, in order to formulate new definitions of the human concept.

I personally believe that anatomical features are a better way to trace an early ‘humanity’ than intellectual, social, cultural and moral criteria, which are all hard to define, perceive and date. A bipedal gait with all its implications seems more than enough to characterise the early humans. If we do not accept this, then we must place the origins of humanity much later in time, according to our idea of what it is to be human. Seen in this light, if we instead seize upon such advanced accomplishments as the use of fire, the cooking of food, the practice of religion, the creation of symbolic art, the use of a complex articulated language or other, safer signs of humanity, then we have come so far forward that this line of argument becomes quite irrelevant for the problem of the early hominids.

A lot of fuss has been made about the notion that our culture has to some extent been instrumental in our biological evolution. But this is nothing unique for us, as many animals also exhibit cultural behaviour that can be important for selection. The decisive factor is that evolution cannot move along anything other than a genetic path. As evolutionary products humans are and always will be purely biological beings. The term ‘cultural evolution’ should be reserved for the process of cultural change.

Biological heritage

Our biological inheritance was certainly determined long before the emergence of anything resembling civilisation as we know it, and in certain important respects long before the origins of humans themselves. For 50 million years our ancestors lived as apes in the trees of tropical forests, after that for another 15 million years as anthropoid apes in trees and on the ground, and after that for several million years more as early humans, mainly on the forest floor. In evolutionary terms, it was during this incomprehensible span of time in the tropical forests that the greater part of our physical make-up and much of our psychological and elementary social behaviour were formed. Neurologically, physiologically and anatomically we are to a very large degree children of this remote forest age.

Truly radical changes in the circumstances of human life first came with the industrial society. For a species with such a long reproductive cycle, this is far too short a time to result in any perceptible biological alterations. Quite simply, the many new demands placed upon us by our new lifestyles have left no significant mark on our genes.

Many mammals have rather poor eyesight, and thus rely primarily on their outstanding sense of smell. With human beings the opposite is true. We have nothing much to boast of in the way of olfactory skills, but we have excellent stereoscopic vision and a good colour sense. We also possess articulated shoulders, arms and hands that can be rotated, mobile fingers with an opposable grip, and a brain that is uniquely good at co-ordinating sight and dexterity. All these qualities are things that we take for granted. Granted is also exactly what they are, granted to us as a biological inheritance from our fruit- and plant-eating ape ancestors during that very long period in the tropical canopy. As we raised ourselves to stand on two legs and our intelligence later increased, this anatomical and physical toolkit became the functional key to our entire cultural development. Without this inheritance we would have been literally incapable of making and using tools and machines, making fire, cooking food, domesticating animals, tilling the soil, building houses, producing metal, sewing clothes, writing words, printing books, playing a piano, pole-vaulting or using computers. So, if there is anything to which someone who values civilisation should send a grateful thought, it is our inheritance from the apes and monkeys.

Exactly like our nearest animal relatives we are typical creatures of daylight. We have little free will when it comes to our daily biorhythm. The fact that we normally sleep at night and are active during the day has not been noticeably affected by access to artificial light. The day-dweller within us is also revealed by our poor night-vision, by the fact that drastic changes in shift-work make us physically and psychologically ill, by our frequent fear of the dark and the depression that often comes with long periods of winter gloom. The fact is that we have exactly the same inner biological clock as other mammals, even the humble fruit fly.

Another concrete example is that of hearing. In the tropical forest, powerful vibrations are so unusual that our ancestors’ auditory organs and nervous systems never needed to develop any real protection against loud noise. This is why we damage our hearing with machine sounds, rock concerts and Walkmans, while hunter-gatherers maintain perfect hearing all their lives. This is a simple example of how cultural development is speeding away from its biological counterpart.

Dependent upon climate and environment, indigenous peoples today can differ considerably as to height, body form and skin colour. But these physiological differences are marginal. All modern humans have essentially the same poor defences against a cold climate. We have no fur, no layer of blubber and no decent system to prevent heat loss. By contrast we possess excellent mechanisms for disposing of excess heat. A naked person, motionless in the shade, is already beginning to shiver when the air temperature goes below 28 degrees centigrade, when the bodily cycle activates itself to cope with the loss of warmth. Not so strange when we consider that more or less all our biological evolution took place in the tropics. The fact that, in spite of this, human beings managed to colonise every climatic zone of the globe by the end of the early Stone Age can only be understood in the light of our cultural abilities.

Humans are very much herd animals. Our extreme need for company, our mobile and hierarchical social structures, our noticeable propensity for group cooperation, our patterns of aggression and conciliation and our collective territoriality are all in their essentials an inheritance from our ape ancestors.

Still, for many people the ‘primitive’ herd instinct is something embarrassing, to be spoken of in an undertone. Certainly this inheritance has its negative sides, but it is easy to forget that the herd instinct also contains the evolutionary codes for mutual tolerance and consideration between unrelated individuals, the very seeds for human morality, solidarity and love. The herd instinct is the key to our complex social life, the toolkit that enables different human beings to combine in functioning societies. To deny this biological inheritance is to deny almost everything that we see as positively human.

We would very much like to see human feelings as something specific to our own species. However, the lie to this is given by the fact that most of our fundamental emotions are regulated by the oldest parts of the brain, the hypothalamus and the limbic system. In fact we share much of our emotional repertoire with other higher mammals. Anger, fear, anxiety, respect, happiness, the joy of reunion, parental love, sorrow, sadness, loneliness, apathy, friendship and sexual frustration, perhaps also melancholy, longing, jealousy, hate and a lust for reveng...

Table of contents

• Cover Page
• Title Page
• Copyright Page
• Preface
• Acknowledgements
• 1: The Tangible Past
• 2: The Evolution of Human Social Life
• 3: Next of Kin
• 4: Traces of the Early Humans
• 5: Becoming Human
• 6: Evolutionary Tools and the Path to Humanity
• 7: A New Sexual Pattern
• 8: Intellect and Language
• 9: Ways of Life and Social Structure
• Bibliography