AQUATIC APE AND AFRICAN EVE
A Search for the Origins and
Evolution of Humankind in Africa
DENIS MONTGOMERY
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© Denis Montgomery 1999
41 Majors Close, Chedburgh, Bury St.Edmunds, Suffolk, England
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This book was originally produced in Corel WordPerfect v8.0, convertible to some earlier versions, to Microsoft Word and other wordprocessors. Page format is A4 and the font is Times New Roman 12pt. The volume is 962KB or 123,000 words.
A copy of the text of this book, the edition of 1995, is lodged in the library of the British Institute in Eastern Africa in Nairobi, Kenya. An electronic copy is being lodged in the library of the Royal Geographical Society in London.
By the same author : The Reflected Face of Africa (1988), Two Shores of the Ocean (1992)
What is past is prologue.
- William Shakespeare
AQUATIC APE AND AFRICAN EVE
A Search for the Origin and Evolution of Humankind in Africa
Denis Montgomery
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Ex Africa semper aliqid novi.
- Gaius Plinius Secundus, [AD23-79]
The sons of Africa must let the world know that we can well do without civilisation if this means that we have to throw our own culture, beliefs and way of life overboard.
- Credo Mutwa, Zulu Chronicler
You cannot force the development of the soul as if it were a hothouse flower; the process must be gentle and gradual. So the true progress of Africa, in our day, did not necessarily fit in with plans for urgent economic development.
- Sir Shenton Thomas G.C.M.G., [1879-1962],
British Colonial Governor.
In this world of crowded houses, people crushed and crammed together, Hima could now believe the Dangi story, that men die only because there is no room for them all.
- Hazel Mugot, Kenyan novelist.
Glorious is this world,
the world that sustains man
like a maggot in a carcass.
- Oswald Mbuyiseni Mtshali, South African poet.
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AQUATIC APE AND AFRICAN EVE
A Search for the Origins and Evolution of Humankind in Africa
Denis Montgomery
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Part One : Our Origins
1 A Broad Backcloth
2 The Aquatic Ape
3 The Driving Force
Part Two : The Stone Age
4 The First Colonials
5 Chaos in the Ice-ages
6 African Eve
7 The Great Culture Jump and the "Cygnus Event"
8 Cro-Magnon from Africa
9 Africa's Neolithic Races
Part Three : The Winds of Change
10 Kalahari, Last Home of the Bushmen
11 Pyramids, Grain, Milk and Blood
12 Cattle Point the Way
13 A Vortex in East Africa
14 The Hottentots
Four : Iron
15 Indian Ocean Seatraders
16 A Beautiful Ivory Bangle
17 Iron Age Convergence in South Africa
18 The Golden Rhino and Zimbabwe
19 Terra da Boa Gente
Comments by Dr Peter Jakubowski
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THE AQUATIC APE AND AFRICAN EVE
An Search for the Origins and Evolution of Humankind in Africa
When I was fifteen years old I was invited by a school friend to spend the July holidays of 1949 at Makapanspoort in the northern Transvaal of South Africa. It was one of the more memorable adventures of my teenage years.
My friend John was the son of Professor C. van Riet Lowe, a notable South African geographer and archaeologist, a colleague of the early giants of African palaeontology, Raymond Dart and Robert Broom, at the University of the Witwatersrand in Johannesburg. He was Director of the Archaeological Survey in Uganda and South Africa during his distinguished career and attended the Nairobi conference when Louis Leakey dramatically revealed his early post-war hominid discoveries in East Africa.
I remember him giving John and me a kindly but serious lecture on the behaviour he expected from us at Makapanspoort. We were to indulge ourselves to our hearts’ content, but there were a few unbendable rules; we were not to shoot anything that moved, we were to obey without question the instructions of the adults with whom we were to stay and we were not to interfere with the diggings. From talking to John, I already knew that something momentous was happening there, and I knew about Darwin and the ‘missing link’.
We were put on a steam train which rattled north through the frozen winter night. In the dawn at Potgietersrust we were met by James Kitching in a battered pick-up truck. He was the cheerful site-foreman of the party which was excavating one of the caves within the isolation of Makapanspoort. For the next two weeks we rambled the wilderness and deep gorge, shot our rifles at targets, watched the wildlife, explored, made maps, bathed in icy rock-pools and played out all kinds of imaginative stories.
The excavations at Makapanspoort were being undertaken by the University of the Witwatersrand under the supervision of Raymond Dart and I was told something of what it was all about. Early Stone Age implements and ancient bones had already been found. I learned about the ‘missing link’, which is how a possible ape-man ancestor was popularly referred to in those days. John used to talk about Darwin and evolution which fascinated him at the time, as much as 18th century British naval history was my passion.
I remember one evening sitting around the hissing paraffin lamp in the rough old farm cottage at Makapanspoort and asking James Kitching to explain what they were doing at the cave. He told us that they were clearing out an old lime quarry and looking for really ancient fossil bones. It was hoped that when they got down far enough more evidence of the ‘missing link’ would be found. He described stratigraphy and how they could make rough estimates of the age of fossils from the depth at which they were found contiguous to particular geological events or known extinctions. He talked about orders of a million years which was a concept of time I found difficult to imagine and said that secrecy had to be maintained because Professor Dart had not completed his evaluations.
Makapanspoort is a deep kloof, or gorge, running into a tableland with steep sides rimmed by vertical cliffs. The floor of the kloof and the slopes leading to the rock faces were scattered with acacia thorn trees, euphorbias, aloes and willow scrub. There were jumbled rocks that had fallen over the ages and a stream ran perennially down its length. Although there were no elephants sheltering there then, there were troops of baboons, rock-hyraxes, dangerous snakes, small antelopes and a wealth of bird life.
Important contributions to human origins were revealed by Raymond Dart. It was electrifying then, and it is still a most remarkable palaeontological site to-day. Remains of australopithecus hominids were discovered, together with bones of other extinct large mammals. Australopithecus (the southern hominoid ape or ‘ape-man’) is not the ‘missing link’, but it was a species at the dawn of mankind more advanced intellectually and physically than any other ape of its time with a greater ratio of brain to body weight than modern chimpanzees and gorillas. Although Makapansgat, as the limeworks cave site is now universally known, cannot be absolutely dated, the australopithecus fossils found there were 2-3,000,000 years old.
I have often thought of that holiday. The effect of passing our days of teenage adventuring in wild country was shadowed by awe at the incomprehensible time-gulf that separated us from the ‘missing link’ who may have lived there. It was an extraordinary introduction for impressionable fifteen year-old boys to the immensity of the fourth dimension of time in Africa.
I am satisfied that early mankind evolved in Africa and Africa has always been home to our core-population. Whenever great natural disasters have occurred in the northern hemisphere, notably the several Ice-ages of the two or more million years-long Quaternary Period leading to the present, a reservoir of people in tropical Africa has been ready to expand again and fill the void after each long period of cold and glaciers.
There are unsolved problems surrounding the evolution of mankind. Controversy about the basic steps continues. Many consider the scenario to be reasonably complete, but there are assumptions which I believe to be wrong although they have been repeated so often that they have acquired the patina of fact. An evolutionary theory has been strung together which seems to fit much of the evidence presently available, but it remains a hypothesis.
Before ten thousand years ago, we had begun the process of deliberate and artificial conversion of the environment and made an evolutionary jump in culture to a new kind of society. This evolution has not ceased, and the development of life on Earth has many millions of years ahead of it, but human Civilisation is the peak of evolution on our planet at this time. Most people are aware to some degree or another how flawed it is and it is plain that we cannot continue to expand our human populations indefinitely without causing catastrophic environmental damage. If we cannot consciously control ourselves, the limitations of the environment will do so with severe trauma. Famines and epidemics will follow a general collapse of ordered human society and we are increasingly witnessing pockets of anarchy in Africa. That collapse would not affect humanity only, we could drag down many living species with us. We are already causing mass extinctions.
Whether we solve the problems created by the society we call Civilisation by internal evolution, or whether we are driven to near-extinction by an environmental collapse, I am absolutely sure of one forecast. The next Ice-age will thoroughly refine our species and all higher mammals, as has happened several times in the past 2-3,000,000 years. We will certainly live in a different society by the time the next warm-period comes. We may have undergone significant genetic evolution.
To try to understand the possible paths of our future, we need to understand our past. Information and informed speculation is growing exponentially too. Specialist knowledge and interpretation is too voluminous for an easy overview. This book has been written as an intellectual exploration with particular emphasis on the dominating role that Africa, particularly the eastern and southern parts, have played in human evolution. The geography of Africa has shaped our evolution and an accumulation of increasingly massive crises in Africa could precipitate the failure of Civilisation.
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I will be mentioning a number of people in the course of this narrative. I am grateful to everybody who has gone out of his or her way to help during my travels. Without exception, professionals and academics were welcoming. The debt owed to the books and papers which others have written is immeasurable and in the bibliography I have listed not only those from which I have directly culled information or opinion for this book but also others which have influenced my thinking and broadened my knowledge over the years.
I must record particular gratitude to busy people who commented on parts of this book: the late Dr Richard Wilding, archaeologist, in Mombasa; Professor Tom Huffman at the University of the Witwatersrand; Dr Tim Maggs and Gavin Whitelaw of the Natal Museum; Leonard van Schalkwyk of the KwaZulu-Natal Monuments Council, Prof.L.B.Crossland of the University of Ghana; and Professor Michael Crawford and David Marsh, authors of The Driving Force. All generously gave me time for discussion or correspondence. The Killie Campbell Memorial Library of the University of Natal provided valuable assistance. Dr John Sutton, retired Director of the British Institute in Eastern Africa, is outstanding in his devotion to the cause of research in that region, and particularly for the organisation of the unique conference on the Iron Age south of the Sahara at Cambridge, England, in July 1994; which I attended.
Lyall Watson suggested that I read Barrow & Tipler’s The Anthropic Cosmological Principle. Elaine Morgan alerted me to the conference held to examine the Aquatic Ape hypothesis at Valkenberg in August 1987, and the publication of papers in book form subsequent to it.
Professor Alan Collier expressed faith in my project. I am indebted to Dr Patricia Collier and Dr Gregory Kerr who read the entire text, detected inconsistencies and omissions and identified poor argument. Gregory Kerr cheerfully undertook the tedious task of correcting my style which was not developed for the rigour of writing in this context. The faults that remain are my own. Miriam Vigar, besides being a staunch friend and a companion on many safaris, helped with text revision and loaned me her computer for weeks at a time when I was far from home.
My friends and companions on various safaris over the years are “the very spice of life that gives it all its flavour”. My wife Sue is always the anchor about which my restless ship swings.
* * *
An earlier copy of this text was lodged in the library of the British Institute in Eastern Africa in Nairobi, with kind acknowledgements from Dr John Sutton, the Director. An electronic copy of this text is lodged with the Royal Geographical Society, London.
Denis Montgomery, Chedburgh, 1999.
PART ONE : OUR ORIGINS
CHAPTER ONE: A BROAD BACKCLOTH
Everybody ponders their origins and there is no society that did not have its creation legend. We do not know when people first began devising stories to account for their existence and their place in the Universe. It must have happened coincident to the emergence of language capable of communicating abstract thought. There is controversy about when this happened, which may be at least 250,000 years ago. According to the present fossil record, Early Stone Age people then inhabited most of Africa from the Cape to the Mediterranean Sea, southern Europe, India, China and Indonesia.
Much later, about ten thousand years ago, people began to live in fixed towns founded on agriculture and ordered their societies in increasing complexity and technical diversity. Codes of laws governing dynastic rule, fixed property and social behaviour, agricultural practice, relations with other societies and religion became formalised. With the invention of writing, not only did the administration of law and custom become sure but kings could have systems of accounting for taxes which required the concept of money. These innovations led to trade and communication between people far from each other.
Religion could become dogmatic and a part of the state. Being able to record ideas to be expanded by later generations and to communicate and compare them with others outside their immediate social group, thinkers and their students explored abstract ideas on any subject in every direction. The classical civilisations were born.
In one way or another, whether oral mythology of tribal societies or dogmatic religion and philosophical systems in civilisations, early evolution theories were based on some form of Divine creation. The Universe was beyond the understanding of anybody, thus a concept of God was born. In civilised societies, argument about evolution was mainly between those who proposed that the world was created in all its finest details by a Master Designer and those who saw that God ordered the principles and laws of the Universe which subsequently, through development by other mystical spiritual forces, often personified in a pantheon of lesser gods, resulted in the world as they knew it.
Revolution in scientific ideas which began in the Renaissance had profound and complicating effects on the philosophy of origins amongst Christian Europeans. Later, the publication of Charles Darwin’s theories and massive research exploded over intellectual society in the West in the second half of the 19th century. Darwin was not alone in his vision, but he was the master and focus of a philosophical revolution. Concepts of an ever-expanding diversity of life from a simple single-cell organism to mankind, through natural selection and the survival of the fittest, sharpened new divides between beliefs in Divine creation and variations on Darwin’s scientific theory of evolution.
During the 18th and 19th centuries, when scientists were exploring increasingly complicated and detailed strands of physics, discovering the nature of electricity and magnetism, developing Newtonian concepts of gravity and cosmology and Darwin was tackling the giant problems of evolution, they continually impinged on the hazy dividing line between the secular and the spiritual. The mysteries of the origins and purpose of the Universe and Life were not being solved by increased scientific knowledge, merely becoming more difficult to understand. Although random chance materialist ideas were proposed to solve the dilemma, many thinkers like Faraday and Darwin himself believed that there was some system of universal natural law, akin to some kind of non-personified and all-pervading deity, that held the key to the mystery. Despite the apparent mechanical perfection of Newtonian physics, 19th century scientists searched for the purpose and connection between the invisible and universal forces they were demonstrating and defining.
At the beginning of this century, an increasing awareness of the uniqueness of the role of chemistry in the existence of life provoked continued argument. Without the seemingly miraculous properties of hydrogen, oxygen, carbon and nitrogen, and the simple compound water, the variety and marvels of life could not exist. Carbon formed in the decay of stars and expelled in their red-giant phases is the ultimate key to life as we know it and carbon-based organic compounds provide the basis for a universal biochemistry with almost limitless flexibility. A suitable temperature range over more than three billion years on Earth enabled this biochemistry to work and life to evolve. From these facts an axiom emerged which became known as the Anthropic Principle: that mankind or some similar warm-blooded reasoning mammal was inevitable and part of a Universal Design.
Continually advancing knowledge of physics and biochemistry, aided by the immense power of modern computers, provoked further controversy. Added to the classical arguments, enormously complex concepts of evolution theory emerged and the process continues. Two contradictory ideas, reduced to simplest terms, dominate thought. Either the evolution of life leading to higher mammals and mankind and their equivalents on other planets is a universal imperative, since all fundamental physical and chemical laws seem to make it so, or carbon-based life and its evolution on Earth is a unique event provoked by random chance. (There is exhaustive exploration in Barrow and Tipler’s The Anthropic Cosmological Principle, 1986,). The two broad alternatives, which can be argued endlessly with impeccable logic, are so at odds that there seems to be no possibility of compromise. Ultimately, every individual pondering these matters is faced with having to prefer one to the other by intuition or belief. There are, of course, large numbers of people all over the world who continue to believe in one or another theory of Divine Creation.
Latest computer-supported mathematics enables the examination of varieties of complicated theorems linking all physics from the almost infinitesimally small to the limits of the Universe. Theoretical models of alternative universes can be created. Superstring theory which suggests a universal mesh of ultra-minute particles in waves of interconnected strings in four dimensions which determine the conduct of all energy can be presented as if it is the ultimate scientific manifestation of God. Definitions and even the language may have altered, but the philosophical problems still stand.
James Lovelock’s Gaia hypothesis suggests that there is a coordinated combined activity of all life forms on Earth and other living planets which works towards maintaining the balance and stability of nature necessary for life to flourish through positive feedback. This is a refinement of the Anthropic Principle, assuming a Universal purpose for life which is Godlike. Lovelock is at pains to point out that the objective of combined action by the interacting complexity of living organisms in Gaia is not to promote the survival or advance of any particular species, mankind for instance.
Prof. Paul Davies (co-author of The Matter Myth, 1991,) wrote in the Daily Telegraph in September 1991:
In some ways the physical universe more closely resembles a living organism than a machine.... Physicists now recognise that inert clod-like matter can, given the right circumstances, almost take on a life of its own.
The amazing power of the human brain propels minds along infinite paths of intellectual exploration. But the simple argument between purpose and random chance remains. Are we here for a reason, or does nothing matter?
* *
When our solar system emerged as a minute vortex in the outer spiral arm of our galaxy, Earth and her sister planets cooled and took up forms and stations much as they are to-day. Further cooling and stabilising resulted in the chemical mix and geological structures with which we are familiar.
But nothing is fixed. Within our galaxy, our solar system moves relative to others and to intergalactic gas clouds which we sweep up. Within our solar system, the sun is converting matter in an atomic furnace to release the energy that drives us and that process has minor variations in reaction to swept-up gases, energy storms and electro-magnetic or gravitic ‘weather-fronts’ in neighbouring galactic space. The form of the planets depends on their size, composition and location. Each planet is different and none has ceased evolving. Our Earth has a fluid centre and the continental plates ponderously move about the surface like the skin on a rotated pot of cooling porridge, causing volcanic activity and earthquakes along the fault zones.
The relative stability achieved after four billion years is jolted from time to time by events both external to our solar system and within it. Swirls of gravitational forces within the rotating disc of our galaxy buffet our solar system causing subtle shifts in the planetary orbits. Those orbits are all eccentric to a degree, none is perfectly circular, and the planets moving on their differing orbits interact on each other. Our solar system encounters rarefied mists of particles and gas molecules. Supernovae bombard us with cosmic ray particles. The close approach of comets and asteroids cause minute wobbles and occasional collisions. When significant external influences occur or several otherwise insignificant events coincide, the Earth’s orbit, distance from the sun and the climate is changed.
The rise or fall of mean atmospheric temperatures over a period of a few thousand years by two or three degrees massively affects climate and fragile lifeforms. In the past, collisions with comets and asteroids or passage through particle or energy vortices have created such disasters that whole ranges of species have become extinct. Nearby supernovae explosions shower our solar system with a variety of energy particles and electro-magnetic wave energy, disturbing our atmosphere, damaging organic molecules in living matter and changing the sun’s output. This level of external threat will surely happen again and again and there is evidence that some activities happen in cycles as well as randomly. Survival of mankind is not certain; we have a tenuous existence.
Our ability to determine climatic changes precisely decreases as we gaze into the distances of further time, but modern geology can draw a fair picture of the more recent few million years. There seems to be some great cycle that causes violent change at intervals of about 26 millions of years. It could be that the Earth passes through a dense meteor swarm or group of asteroids when a number of the earliest collisions occurred. The intensity of that cyclical event seemed to vary, possibly with the number and size of collisions, causing greater or lesser mass extinctions of species. The worst of these mass extinctions is detected at about 250 million years ago. Many of these resulted from wave expulsions of lava, engulfing parts of continents. But the cause of these engulfing lava flows is still disputed. They could have been triggered by extra-terrestrial events.
Whenever mass extinctions of great magnitude occurred there were always remarkable survivors from which evolutionary lines grew to fill vacuums until other factors, or new extinctions caused by external events occurred, to refine and spur new developments. In South Africa in 1998 a fossil was discovered that suggests that quite large mammalian creatures, something vaguely like a sheep, existed long before the age of the dinosaurs. As more of the Earth is surveyed by scientists, many surprises will still be revealed.
An extinction of lesser but still massive severity than that of 250 million years ago resulted in the end of the dinosaurs, numerous smaller animals, sea creatures and many plant species about 65 million years ago. The demise of ammonites in the fossil record is a yardstick for that catastrophe. It has been progressively well-researched and documented in the last ten years and has been shown to be the result of an impact by the core of a comet or a large meteor on the shores of the Yucatan Peninsular. A fire ball and severe global temperature changes of up to ten degrees below and above the mean, together with chemical fall-out, caused the devastation. Small burrowing mammals and proto-mammals were the majority of larger land animals that survived and it from them that the domination of Earth by mammals proceeded.
Between 30 and maybe ten million years ago, the Miocene epoch, all mammals proliferated and apes evolved separately from monkeys. The Asiatic apes, ancestors of the orang-utans and gibbons, split away as tectonic drift separated tropical Asia from tropical Africa. In Africa, species from that epoch have now been identified and the search continues. In 1991, for example, Glenn Conroy of Washington University, St.Louis, led an expedition in Namibia which reported the discovery of a hominoid jawbone in the hills near Otavi close to the Etosha National Park. The jawbone shows that the owner’s diet was probably mainly soft fruits, berries and leaves; a diet something like that of modern mountain gorillas and indicating lush vegetation. They named the new species, otavipithecus namibiensis, and its jawbone is dated to about 13 million years ago. In 1996, a tooth with ancestral hominoid attributes was dated at about 18 million years ago, and it had been found in Namaqualand, South Africa. The inference is that in that era the climate of southern Africa was suitable for forest-dwelling apes despite its distance from the tropics.
Tropical East Africa is not the only source of mankind’s ancestors. The climate and geography of Africa has changed greatly over millions of years coincidental to shifts in the tectonic plates which often appear to be contradictory to the climatic changes. Eighteen million years ago, southern Africa may be considered to have been closer to the south pole according to geological evidence, for example. Africa spawned several remote ancestors of mankind and the modern anthropoid apes, and ancestral apes evolved wherever the climate was suitable. As climate and diet changed, all species were refined and some become extinct.
A particular type of ancient ape, ramapithecus, who lived 12-10 million years ago, is sometimes considered to be the best candidate for our direct ancestor. This is principally because this family of extinct species had teeth which were adapted for chewing seeds, nuts and tough roots as well as fruits and leaves. This suggested that they lived on the fringes of forests in grassy woodland and savannah and they were already living in an environment which resembled that of the early hominids millions of years later. Their range was from Africa to southern Europe and Asia which is consistent with the equator lying somewhat further north at that distant time. Africa has been moving gradually northwards as tectonic drift shifts the continents about on the fluid core. Yet, the latest evidence shows that despite the early positioning of Africa further south, ancestral apes experienced an equable climate throughout the continent from time to time. Dramatic climatic change superimposed on continental locations seems to be a dominant factor. This affects all species of living creatures.
Recent genetic studies show that ramapithecus was not on the direct line of descent to hominids, but rather that particular family of species was situated on a line of descent leading to other great apes, probably including the Asian orang-utans and gibbons besides species that have become extinct. Hominids separated from the ancestors of chimps and gorillas after the African group became distinct from the line in which ramapithecus was found.
At the end of the wet and warm Miocene epoch (approximately 10 million years ago) general cooling of the Earth reduced rainfall and the tropical forests shrunk. Much of eastern Africa became scattered woodland, grassy savannah and dry grassland.
But, within these great cycles, shorter waves of change occurred, and they become clearly definable in the last two million years (the Pleistocene) with alternating cool and warm periods. Maybe there is a mild wobble in Earth’s orbit or we pass through a local skein of dust and comet fragments. Because we are in a relatively warm period which suits us at present, we of the northern hemisphere have called the cool periods Ice-ages because much of Europe and North America are covered by glaciers during them. Our far-distant ancestors and those of the other large African mammals survived the Ice-ages in the tropical zones. It was the intervening warm periods which stimulated their evolution, in the broadest way, to the present peak and the process continues.
Tracing the ape line in Africa, there was a divergence between the ancestors of modern gorillas and chimpanzees, who stayed within the rain-forests, and ancestral hominids, who lived on the savannahs, sometime between 4-8 million years ago. During that immense time, a particular line of African apes, with some ‘ramapithecus-type’ as a conjectural ancestor, split into two distinct mainstreams of evolution; the forest apes, gorillas and chimpanzees in one stream, and ancestral hominids who developed into upright-walking australopithecus in the other. Australopithecus had a brain to body weight ratio greater than any modern ape and their fossils have been found from South Africa to the Red Sea.
Fossils from the past 4 million years illustrate evolutionary progress and there is now quite a respectable record. The remains of hundreds of individuals have been dug up and assembled from the South African complex of Sterkfontein, Swartkrans, Kromdraai and Makapansgat; all along the East African Rift Valley from Olduvai and Laetoli in Tanzania to Lake Turkana in Kenya and onwards through the Awash Valley and the Hadar in northern Ethiopia. Recent discoveries in Chad show that residence near large bodies of water in Africa has been important to the development of hominids in Africa.
By the late 1970s, enough fossils of these hominids had been examined and dated for there to be a consensus about them. Richard Leakey in his popular book, Origins (1977), described the extent of knowledge at that time. Since then, more fossils have been recovered and scientists have analysed them and the environments of their sites. An extension of knowledge and speculation has occurred in the past ten years or so, but it has been in detail. No new amazing revelations have emerged. It appears that the sites that are geologically suitable for the exposure of fossils of that period in Africa may have yielded their limit of broadly-based knowledge. More complete skeletons may be found, a greater range of small variations may emerge and there may be shades of meaning and interpretation that can be exploited, but the grand picture seems mostly painted in. By 1997, australopithecine fossils had been classified arbitrarily into at least seven separate species and as scientists delve ever more deeply into the detail of differences between individuals this trend will continue until a change in method or a revolutionary series of major discoveries occurs.
There were extinctions and retreats during Ice-ages and re-dispersions when the climate was amenable. I see this as a great pulsing of mankind and other migrating species from the giant warm heart in tropical Africa. Early Stone Age people, hippos, rhinos, lions and elephants roamed Europe during the warm interglacials. Probably many of the Early Stone Age colonisers did not survive the extensive Mindel Ice-age complex around a half million years ago. But there would have been survivors when the next pulse occurred. In the northern hemisphere, mankind and other mammals adapted and were forced along evolutionary paths by the rigours of dramatically changing climate. And whenever numbers were reduced fresh battalions came out of Africa, themselves changed in response to different challenges in their tropical heartland.
There are fundamental questions outstanding. How and why did a small, somewhat omnivorous ancestral ape, let’s say a ‘ramapithecus-type’ for convenience, pass through an evolutionary jump to australopithecus, a vertically-walking creature with a relative brain capacity (weight of brain proportional to the body) which outstripped that of all other land animals? Why didn’t a ‘ramapithecus-type’ evolve simply into an ape equivalent of the African baboon? ‘Ramapithecus-types’ evolved into modern forest apes which coexist with forest monkeys, not only in Africa but also in tropical Asia. On the vast African savannahs, why did a ‘ramapithecus-type’ or some other cousin make a quantum jump in evolution instead of gradually developing alongside their fellow primates, the ancestral baboons?
* *
In the 1960s and 70s, it was proposed that a ‘ramapithecus-type’ ape, and possibly a more specific relative, Kenyapithecus, lived in the trees of the declining rain-forests and was forced to evolve by natural selection into a savannah ape. Unable to survive on the savannah by fruit eating, the ape changed to exploit the possibilities of hunting. The upright stance was the result of the need to stand higher to seek prey and avoid the big cats, bipedal locomotion enabled them to chase antelopes while carrying weapons, improved hands enabled them to become tool and weapons makers, bigger brains were necessary for using weapons and coordinating hunting teams. Team-work in toolmaking and hunting required language and bigger brains still. The division of labour between hunting males and child-rearing females stimulated pair-bonding with sophisticated socialising and greatly increased sexual activity which led to monogamy.
One of the main distinguishing features of mankind, the loss of hair or fur, was a main feature of Desmond Morris’ book, The Naked Ape (1967). Hominids, it was suggested, lost their fur because of the need to cool themselves by perspiring in the heat of the hunt. This ‘nakedness’ was more advanced in females because it played a dual role by increasing sexual attraction for pair-bonding, which also led to the evolution of prominent breasts and buttocks.
Robert Ardrey devoted massive research and writing to the ‘hunting hypothesis’ and he made a plausible case. He expanded his theories to explain aggression and warfare through a genetic ‘territorial imperative’ developed during this early savannah period. But there were a number of gross errors which became obvious as the result of studies of San-Bushman nomads in southern Africa and various other species of predators. Hunting is not carried on by running about in a specialised vertical stance with much verbal discussion, but by crawling and dodging about silently in cover. Four-legged running is much faster and easier than two-legged. Evidence from observation of surviving African nomadic hunter-gatherers is that they were not aggressive socially and did not fight for territory.
Those modern hunter-gatherers whose natural aggressive nature has been extensively observed and reported are those who have been constrained by their environment in tight territorial pockets. The natives of the rainforest in Papua-New Guinea mountains and parts of the Amazon basin are those usually quoted. Their particular circumstances are very different to the lifestyle of African savannah nomads. Historically, warfare has been a product of societies within civilisations, competing for territory or trade routes, often after artificially-induced environmental decay or adverse changes in climate. Hunting-and-gathering communities, pressed close to one another by a restricted environment as in Papua-New Guinea or Amazon rainforests are under not dissimilar pressures to competing city-states. Studies of other primates in the wild show that human behaviour is not different in style, but rather in degree and complexity. Push any hominoid band too close to another and strife results.
The ‘hunting hypothesis’ was discredited and a gentler scenario was generally accepted as the convention. Richard Leakey wrote in Origins (1977):
Meat eating was important in propelling our ancestors along the road to humanity, but only as part of a package of socially-oriented changes involving the gathering of plant foods and sharing the spoils.
It was proposed that tool-making developed hands and brains, vertical stance was needed for surveillance and especially to carry weapons, tools and possessions while food-gathering or hunting. As gathering and hunting became more successful and complex, social organisation developed and communal food sharing and preparation took place, enhancing the need for language and more brain power. Positive feed-back promoted greater variety and sophistication of all these facets of behaviour, particularly the complexity of social behaviour as children matured more slowly with the advent of larger brains.
Chris Stringer and Robin McKie in their masterly summary, African Exodus (1996) presented what I find to be the most convincing scenario for a savannah origin for mankind.
For many millions of years, in an era we call the Miocene, the primate group to which we belong - the apes - had been thriving across the warmer parts of Africa, Europe and Asia. These large-bodied tail-less, relatively large-brained animals were a highly successful, widespread and diverse group. Then they began to die out, losing a battle for resources with monkeys, who tend to be smaller-brained and smaller-bodied, but who nevertheless began to take over the forest of the Old World ... about ten million years ago. The reasons for this shift in the primate power axis are not clear, though anthropologists believe that climate change probably played a key role, since the Earth began to get cooler and drier then. In addition some scientists point to the ability of monkeys to digest relatively unripe fruit, a power that would have allowed them to pick off less mature produce ahead of their ape competitors...
... some scientists believe the rise and spread of the monkey ... played critical roles in our own evolution. Faced with creatures that displayed greater flexibility in diet and environmental tolerance, began to adapt to life on the level. Our ape ancestors were forced down from the trees, and once on the ground, evolved upright gait and later the large brains and tool technology that are the distinctive hallmarks of hominid intellect.
Those apes forced from the trees to the east of the Great Rift Valley, the emerging savannahs, become hominids and those to the west, within surviving rainforests, became the chimpanzees and gorillas. This is the so-called ‘eastside’ hypothesis.
There are several more benign hypotheses than Ardrey’s picture of the emergence of vicious gangs of snarling ‘cat-men’. But there are still a number of awkward, unanswered questions and I detect circular arguments. In any case, the discovery of early hominid fossils in West and South Africa tends to negate the ‘eastside’ concept. If hominids developed on the savannahs to escape competition from forest monkeys, how did they survive amongst the more agile, omnivorous savannah baboons and prolific vervet monkeys and the cats, hyenas and packs of African hunting-dogs? How did chimps and gorillas survive the competition of forest monkeys and evolve continually and in stability throughout the forests of Africa until today when it is only mankind that is causing their extinction?
Did our ancestors really have to walk around vertically? Australopithecus walked vertically four million years ago and how did it benefit them? They were not habitual tool-users and did not carry kits around with them, so what had tool-using to do with promoting vertical stance. Homo habilis, the regular tool-users, evolved in what is usually stated to be a separate evolutionary path a couple of million years after two-legged walking started. If Australopithecus evolved from tree-climbing forest apes, they did not need to stand tall to pluck fruits, as some anthropologists have suggested. They were only about four feet tall, anyway, much the same height as a vertically-stretched male modern baboon which runs fast with four limbs on the ground and climbs around in trees with great facility.
Why are we naked? Furlessness in the tropics is a great disadvantage for it leaves the skin vulnerable to insect bites, parasites and the weather. At higher altitudes in South and East Africa people today need clothing and fire to combat cold. It is claimed that a colder dry climate, resulting in declining tropical rainforests, was the originator of the evolution to hominids. Why do we sweat such a lot if we evolved in response to a dry environment in which heavy sweating without frequent drinking kills very quickly? There seems to be no reason for natural selection to have led to nakedness and sweating on the dry savannah plains of Africa; indeed it would have been counter-productive.
Why did we develop language and massive brains? Baboons and vervet monkeys are excellent savannah food-gathers with highly disciplined clan societies; wild dogs, hyenas and lions are successful cooperative hunters. Gorillas and chimpanzees are efficient gatherers and have complex family groups. Some chimpanzees are occasional cooperative hunters and meat eaters. None of them needed to develop complicated spoken language. Big brains create problems in giving birth and rearing children with many years of immaturity. Why did we need to make sophisticated stone tools and habitually use them? Presumably not to survive, since none of our primate cousins need them? Nor did australopithecus !
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Not only did mankind evolve in Africa, but the mainstream core-population has lived there continuously through incomprehensible millions of years. Whereas, humanity in the other continents has either been in a state of flux or a newcomer through migration from Africa, it is on the mother-continent that an unbroken path in time exists through ancestral genes and cultural behaviour. There are important gaps in our charting of that path but there is no doubt of its existence.
The mass of Eurasia lies mostly in the northern temperate and frigid zones and the tropical lands of the Americas are the islands of the Caribbean and narrow corridor of Central America. Australia was cut off from the mainstream of evolution by continental drift so far back in time that mammals never evolved there. It is the special position of Africa with its huge tropical landmass with the precise environment in which mankind evolved that is so important. Climatic cycles, especially the Ice-ages, had lesser impact in Africa; the effects of climatic extremes which forced animals to move, adapt or die when the glaciers moved south from the polar regions were cushioned in Africa. Of course changes occurred there too but there is sufficient geographical diversity on that continent that the mainstreams of life could survive either by adapting to the lesser changes of temperature and rainfall occurring there, or by moving relatively short distances unobstructed by oceanic divides or high mountain ranges.
As Ice-ages came and went, temperature and rainfall zones shifted on the surface of Africa. Forests and savannah vegetation moved and adjusted to climatic cycles, for our distant vegetable relatives although individually fixed to the ground can migrate efficiently en masse given sufficient time. As vegetation migrated, animals followed. In the last two million years there was nowhere in Africa where most species could not find a niche in which to survive.
If the highlands became too cold and wet for comfort, mammals could move to warmer lowlands. If savannahs were invaded by rainforest or dried away to desert, a modest shift of several hundred miles led to a suitable habitat. Some species expired from stress and physical inadequacy in even modest migrations, of course, and some species were at a fragile margin in evolution where migration was insufficient to ensure survival without genetic change. For example, giant races of several species evolved into new species at suitable times and subsequently disappeared. Evolution was stimulated by climatic change in Africa but it was a honing and refining process rather than one of wholesale extinction. Positive cycles were also at work, and it was the space and ease of movement that dominated.
Perhaps by trying to understand how mankind evolved in Africa, we can begin to see the modern world and its future more clearly. It is not only curiosity that should keep us seeking the ‘missing link’ between ape and australopithecus and onwards along the homo line. Will there be a clear link between homo sapiens and homo sapiens superior some time during or after the next ice-ages for our descendants a millions years into the future to see? Will there be an opportunity for homo sapiens to evolve further?
CHAPTER TWO : THE AQUATIC APE
The Niger River delta in West Africa is a vast region of flat country which was covered with rich tropical rain forest. Threading the forest, streams and rivers spread like a system of veins in a leaf: draining the land, joining each other, flowing into tributaries of the giant artery of the Niger River, which then began to split and spread like a fan to meander through a growing network to the ocean.
The people of this region have been familiar with their tropical riverine environment for thousands of years and their ease and mastery of it could be understood from any number of daily observations.
There was a place where a clearing in the forest overlooked a tranquil section of the Ethiope River where a pool was clear right down to the bottom, maybe twenty feet deep. While picnicking there in 1957, I was disturbed by half a dozen boys aged between about nine and thirteen coming down the track. They pulled off their ragged shirts and shorts and dived in to swim and play in the clear waters of the deep pool. They were like sleek brown dolphins flashing through the pale green. They would come up for a quick breath then lazily roll and pull themselves down with strong paddling and slow sweeps of their arms before holding them to their sides. Their heads were held up and eyes watched where they were going in the clear water. They propelled themselves with their legs, like frogs, or kicking them together up-and-down so that their whole bodies rocked rhythmically. They climbed out onto the bank and dived back in, legs together and feet pointed, arms clasped to their sides, naked brown torpedoes. With little planing movements of their hands they steered in a graceful, varying curve down to the bottom, along it and up to the surface. Deep in the pool again, they paddled strongly with practised strokes, twisted and turned their bodies, jackknifed and changed direction gracefully, like three-dimensional ballet dancers.
Another time I was waiting for a canoe-man to paddle me across the river at Sapele. A woman was feeding a plump naked child, chatting to friends and when the child ceased its sucking and began to wriggle in her arms she picked her up and dropped her into the river. The child bobbed in the water, on her back with arms and legs waving. The woman, still gossiping with friends, looked at her off and on and even pushed her under with a casual touch. It was all so natural. The child’s face surfaced from time to time as she squirmed in the water and made happy gurgling sounds.
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Descent of Woman (1972) was written by Elaine Morgan seemingly in protest at the overpoweringly masculine tone of Robert Ardrey’s series of books commencing with African Genesis (1961) and Desmond Morris’ The Naked Ape (1967) which assumed that the evolution of mankind occurred primarily because of the massive thrust of males going out to hunt and the imperative of behavioural and genetic changes that this generated. Elaine Morgan was a professional writer and a layperson and I enjoyed reading her book for its witty and competent feminist refutation of Ardrey’s hunting hypothesis. But I was also struck by her logic and the exciting alternatives which she proposed. Ten years later she wrote The Aquatic Ape (1982), more scholarly and up to date.
Elaine Morgan developed a hypothesis originally suggested by marine biologist Sir Alister Hardy in a little-noticed lecture in March 1960 and an article in The New Scientist in April that year. The argument, reduced to simplicity, was that our ancestral apes who lived in the rainforests were trapped by the climatic changes of the cool dry Pliocene epoch. Rather than struggle for existence as the forests retreated and the dry savannahs expanded in eastern Africa, they exploited the richness of the tropical sea coasts. They became aquatic apes and the particular challenges of living in and around the littoral led, by natural selection, to all the dramatic changes observed in australopithecus and the early homos.
Vertical stance developed through wading, standing and swimming in the sea amongst tropical coral reefs. Fur or hair was lost because it is a hindrance in salt water. Abundant sweating and tears in the eyes helped to rid the body of excess salt and to lubricate naked skin and eyeballs. A fatty layer under the skin grew to act as insulation during prolonged bouts in the sea, women having more fat because they performed less active roles. Their fingers, hands and tactile efficiency leading to habitual tool-using developed to prize shellfish off the reefs and to break open crayfish, crabs, mussels and oysters (all particularly fiddly activities) and later to spear swimming fish and octopus.
Men, unencumbered by children, became expert fishermen and brought back surpluses, a preliminary to taking on a specific hunting role on the savannahs. Sharing food surpluses at a communal campsite in a gradually more sophisticated social system developed naturally because shellfish have to be prepared before eating and a man can easily catch or spear more fish than he can eat.
Women continued to gather birds’ eggs, insects, fruits, herbs, roots and vegetables in the coastal forests; turtle eggs and the cornucopia of shellfish on beaches or low-tide reefs. It was an easy division of labour. Males specialised in fishing, later straddling logs as boats, and used their growing expertise to improve their ability as hunters of small antelopes and other mammals in the coastal forests when sea conditions were unfavourable or the community felt like a change in diet. Honey and other stored insect foods became important as dexterity and intelligence made them accessible. Most females stayed in shallow water with their children, harvesting shellfish, went gathering in the forests and fostered the home base.
Speech began to develop because survival was improved by individuals being able to communicate against a background roar of waves, scattered over reefs and in rough water. Arm signals and gestures by chimpanzees swimming and splashing about cannot be meaningful in those conditions and simple barks or calls are vague or lost in the thunder of surf. The sharply increased variety of needs for urgent and precise communication demanded an extended vocabulary for survival or convenience. Females needed language most of all to handle and teach youngsters in the dangerous environment.
Language was facilitated because changes in nasal passages and throat and the breathing mechanism in the brain were coincidentally needed to enable the aquatic apes to control breath easily through their mouths. Without exact control of breathing, sounds come out as gasps, grunts, moans, barks and roars; precisely the sorts of noises that other primates make. Vervet monkeys of the African savannah warn each other about dangers with particular calls specific to each predator, but these are in the form of different barks.
Considerable research has now been made into primate communication after many hours of observation and recording of several species and although it has been established that all primates have a hitherto unexpectedly large repertoire or vocabulary, sufficient to enable them to live profitably and safely in their habitats, voice control like humans has not been necessary and has not been developed. Despite our already exquisite breath and voice control compared with other higher mammals, professional singers spend long hours learning to refine them further.
Controlled breathing was necessary to take deep breaths before diving and to consciously manage the time spent underwater, holding it or letting it out slowly, or making quick and economic inhalations. No non-aquatic mammals can do this which is also required for voice control and talking.
The position of the larynx and the opening to the lungs is also critical. Humans can easily block off the breathing passage to mouth and nose and do it both unconsciously and consciously, thus preventing water entering the lungs while diving or working and playing in the ocean surf. Other land mammals cannot do this. It has its disadvantages, however, because we cannot drink and breathe at the same time like baboons, antelopes or horses for example. It results in our annoying habit of loud snoring when asleep. It also has its effect on talking: human babies can drink and breath at the same time but they cannot articulate efficiently. When children’s larynxes and throats develop to the stage when they cannot breath and drink simultaneously, they suddenly are able to control sounds and begin to form words.
These fascinating physical changes in humans are not duplicated in other primates and are some of the more convincing connections between aquaticism and humanity. There seems no reason why these complimentary developments should have ever taken place in an inland, savannah environment whatever the pressures. Particularly if there was no survival imperative to talk in complex language, which is not seen in relation to the communication ability of monkeys and forest apes, why was it necessary to alter the breathing apparatus so that drinking in a potentially hostile environment became more difficult and dangerous?
Language encompassing abstract thought may have evolved in the last quarter of a million years, but that does not preclude simple language directed at immediate matters five million years ago. I do not doubt that breath control to facilitate swimming and diving came before talking. When the apes found that developing that new ability made them able to make new sounds, they began expanding their range of grunts and barks under the stimulus of the seashore life and more complex social interaction.
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Upright walking, naked skin, heavy sweating, the advent of simple speech and tool-using four or five million years ago might seem obscure speculation to many people to-day, but sexual activity is something we all know about. Ardrey, Morris and others devoted much space attempting an explanation of the strangeness of human sexual activity. Ardrey maintained that the unique human trait of the female prone with the male on top resulted from the aggressive nature of the hunting imperative and male demand for sex at his convenience.
Only modern humans habitually have sex at night and lie down to it; all other mammals indulge when they are active in daylight. A male ape mounting a female on all fours on a coral reef or in surging shallow water is not practical and impossible when swimming. The assumption can be that they learned to do it face-to-face and hanging on to each other in addition to the male mounting the standing female fashion of all land mammals. Humans have the desire for sex in a variety of physical positions as well as the most common way when lying down which must have coincided with skeletal changes to vertical stance.
Together with changes in the pelvic bones necessary for efficient swimming and a vertical stance, the female vagina shifted its position forwards and became buried deeply within two separate folds of skin to protect it in a salt water environment. Males developed a rather longer penis compared to their ape cousins to compensate for these changes in the vagina. Morgan suggested that female problems with orgasm follow because of the interruption in physical evolutionary progress. Humans are apes who were changing to the physiological structure of aquatic mammals and the process was arrested. We are neither chimps nor dolphins.
Frontal sex occurs amongst all the true seagoing mammals like dolphins and whales and also among the other great apes, and Morgan cites orang-utans, the large arboreal apes of Indonesia. Orang-utans spend most of their lives high in rainforest canopies where conventional land-mammal sex with the male mounting from the back is as difficult as it is in the water. But if we were savannah chimps living neither in high forests nor in the sea, we would not have had to be different. Were we to have evolved on the savannah, our sexual manners would have been like the baboons. Lying down to it is the really unique human practice and that style is similar only to the dolphins and other aquatic animals. It is a dangerous way on the savannah with predators about and unlikely to have evolved there.
Prone frontal sex, our particular speciality, may be considered habitual in modern humans because it is the way that most people usually do it. Especially, it is the way that a couple anywhere across the world of whatever culture or ethnic heritage will usually approach it for the first time. However, despite its ancient roots in the aquatic ape phase it is not a genetic imperative and our species is remarkable for sexual foreplay, experiment and variety. It is interesting that Hans-Joachim Heinz, an anthropologist who had a San-Bushman ‘wife’ for many years in the Kalahari Desert, described most of their womenfolk preferring to enjoy sex lying on their sides with the man behind. It is the particular factor of the prone position which makes us unique. We have sex lying down most commonly and this is the trait which we share only with the aquatic mammals.
Both gorillas and chimps will indulge in frontal sex when it suits them and they are sufficiently relaxed and undisturbed. The pygmy chimpanzee, or bonobo, (pan paniscus), has not been as closely studied as the ‘ordinary’ or common chimp, (pan troglodytes), the subject of thirty years of close research in the Gombe Reserve on the shore of Lake Tanganyika, and elsewhere. Recently, knowledge of the bonobo has begun to accumulate and they have habits more similar in some ways to humans than any other primate. Bonobo chimps have sex in any position, often while they are high in trees. They seek sexual gratification with any available partner and in groups; male, female or immature and it would seem that this sexual activity with them is intense mutual grooming and expression of solidarity and comradeship. Maybe the bonobo, who inhabit the high rainforest of the Congo Basin, have evolved social systems in a specialist restricted habitat in the same way that semi-aquatic apes were restricted in their specialist zone along the East African littoral.
The other eccentricity of human sexuality, that human females are always sexually active and do not come ‘on heat’ during oestrus, has also been subject to much speculation. Elaine Morgan did not convince me with her early suggestion that it was due to lack of sexual satisfaction by females during the transition to the face-to-face position. Later, she returns to comparison with the orang-utan. Orang-utans also have sex throughout the female’s ovulation cycle and it seems that this is on the demand of the dominant male. Orang-utans reportedly show no affection for each other, probably because their bonding is a genetic imperative and requires no nurturing. The African anthropoid apes are different: Nicholas Humphrey in The Inner Eye (1986) stated:
.... the gorillas’ strategy for survival - the strategy of relying on the social group to provide both a protective mafia and a kind of polytechnic school - is one we share. Indeed it is one which we human beings have made the keystone of our whole existence.
It is not only a keystone, but it is one which is cemented in place by mutual affection, loyalties and sentiment. Youthful sexual infatuation is probably the most powerful mixture of emotions many people ever feel, but it is not an absolute genetic imperative. Humans are not monogamous instinctively like the orang-utan, nor by custom in several modern societies. Africans, particularly, were noted for their customary polygamous practices which followed from males having a lower survival rate than females. Amongst all people, before marriage and after, a great variety of sexual contacts are engaged, whether consummated or whether an ‘affair’ or ‘relationship’ develops or not. Often the attraction is fleeting and experienced in casual daily contacts, but it is universally possible for us to resist sexual demands and desires.
Grooming among primates in cooperative societies has survival importance for group cohesion, to convey security to youngsters and weaker members, resolve tensions following everyday frictions, and strengthen leadership structures. What looks like two African apes or monkeys picking nits out of each other’s fur goes much further. Grooming is not that far away from mutual sexual pleasure and sexual behaviour is less strictly determined by females’ oestrus cycles in modern chimpanzees. The ‘common’ species of chimp females, not in oestrous, will present themselves and accept copulation to assuage particularly excited disputation with a male when other submissive behaviour and normal grooming has failed to relieve tensions. Many human women would admit to similar practice.
Grooming activity as fur disappeared in our far ancestral past must have changed to caressing and touching bare skin. Caressing bare skin was the socially essential and physically pleasurable path leading to frequent sexual stimulation. Modern sex therapists all emphasise the critical importance of caressing and touching bare skin in treating sexual difficulties such as impotence or frigidity. The psychical aspects of oestrus in aquatic apes fell away whilst the biological process of ovulation continued.
The anarchic sexual activity of bonobo chimpanzees, amongst whom there are apparently no taboos, may seem to argue against a semi-aquatic phase in earliest humans: if bonobos have a sexual lifestyle which duplicates ours, then perhaps an aquatic phase and ‘nakedness’ has no relevance?
Common chimps and gorillas evolved in a wide and varied environment, spread from the savannah fringes and mountains of East Africa all along the forested zones of West Africa. The bonobos split away from the common chimps, becoming a separate species, and developed exceptional mammal sexual behaviour in their severely restricted, high rainforest environment in the depths of the Congo Basin. If we had never had any other experience than that of roaming the open and varied savannah, like baboons, would we have diverged sexually as we have? Is it not possible that we must have had a heritage like the bonobos: restriction to a specialist environment, with particular problems and stresses.
I suggest that those particular stresses besetting a complex higher primate created special communal social traits and, by the standards of other primates and mammals, exceptionally ‘permissive’ sexual behaviour as an extension to group grooming. Where our other anthropoid ape cousins evolved complex social interactions in common with ourselves, it is only ourselves and the bonobos who reached extremes of varied sexual behaviour. It is reasonable to conclude that we must also have had a particularly intense period of environmental specialisation with particular communal social structures and stresses in our past. Otherwise, as I frequently question, why are we not merely a savannah sub-species of the common chimpanzee living alongside baboons, as all forest apes live alongside forest monkeys?
The bonobos became fatally fixed in their specialisation whilst we have spread over the Earth because our ancestors’ seaside environment on the Indian Ocean coast was contiguous to and easily accessible to the savannah. Indeed, as climate fluctuated, the savannah touched the coast forcing variation on the aquatic apes whereas the bonobos’ ancestors expanded and contracted within their Congo rainforest retreat as it expanded and contracted. The bonobos, like the common chimps and the gorillas, now face inevitable extinction outside artificial reserves.
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In the rich seashore environment, once the essential genetic changes had been well-established, it could be assumed there was evolutionary stability while numbers grew and the aquatic apes migrated along the whole eastern African littoral, filling this special environmental niche. Later, they moved up the few perennial rivers and colonised the inland valleys and lake shores of the Great Rift Valley. Migration progressed as far as the Transvaal highveld in South Africa, up the Nile and along the northern fringes of the central rain forests to the Lake Chad region. The australopithecus stage was achieved and the evolutionary march to mankind had begun through minor extinctions and diversification into the homo range.
In the 1970s, Ardrey and Morris argued that vertical stance, heavy sweating and naked skin evolved on the savannah because they were required for the ‘hunting hypothesis’. At the end of the previous chapter, I briefly remarked on the opposite proposal, that these three particular features were not only of no advantage on the savannah but were positively disadvantageous and life-threatening. (Hunting is best pursued by creeping low to the ground and attacking with silent four-legged speed, not by running vertically and calling to each other. Heavy sweating which cools naked skin dehydrates the body rapidly and unless there is frequent recourse to drinking water on the dry savannah, death follows. Hair or fur is necessary in the tropics as protection against flying insects which carry parasites and disease.)
If we are convinced that these traits developed in a semi-aquatic tropical environment, how did descendants of the aquatic-apes, the australopithecines, survive after they moved away from the shore? It can only have happened because the aquatic traits were offset by newly-evolved superior intelligence and cooperative social behaviour in a sharing communal lifestyle which had been learned and acquired before the move. There has to be an assumption that evolution to the australopithecus level had already taken place. And that is precisely why there is a break in the fossil record at that evolutionary level. Palaeontologists are not looking in the right places; they need to unblinker their eyes.
Australopithecus males scavenged and hunted small mammals and helped females gather vegetarian foods, eggs and insects. Nevertheless, they were water-oriented for survival and their natural habitat was along rivers and around the lakes of the Great Rift Valley and elsewhere in tropical Africa, so males learned to adapt technique and continued fishing. Being naked, in a more rigorous climate in the interior, they were forced to start wearing clothes of animal skins which stimulated male hunting activity. Nakedness in the cold of highland nights eventually demanded the taming of fire. It all continued to follow acceptable logic.
Lyall Watson, in Lightning Bird (1982), suggests that early hominids did not scavenge, any more than modern primates do in the wild. Hunting small animals preceded scavenging because it is easier to kill insects, reptiles, birds and small mammals than to chase predators off their kills. Some palaeanthropologists see hominids learning to hunt at the earliest stages as a result of becoming carnivorous on the savannah plains from chasing cats and dogs off kills by group action. Watson, citing Adrian Boshier a man who spent many years living in the wilderness without firearms, shows that it requires far greater effort, both physical and psychic, to chase predators away from kills than to catch and eat the variety of small animals that modern baboons and chimpanzees also catch and eat.
The aquatic experience, when hominids hunted and gathered seafoods, would have been an important learning period inculcating a hunting custom. Proceeding from hunting fish and shellfish in shallow reef waters, it is an easy jump to regular hunting for vulnerable prey on land. Aquatic apes would be more likely to become savannah hunters than their ancestors, who were also ancestors of the chimpanzees.
It is precisely in riverine and lacustrine habitats, or close to them, where all the earliest hominid fossils have been found. Despite the prodigious efforts of the Leakeys, Johanson and others with their teams of skilled and intuitive colleagues and assistants, the link between an uncertain ancestral ape and australopithecus has not been found in those habitats. In Richard Leakey’s latest book, Origins Reconsidered (1992), he described his frustration and the uncertainties still prevailing.
Maeve Leakey, Richard’s wife, has taken up the continuing task to push back the frontier. In an article for National Geographic in September 1995 she describes the discovery and evaluation of the earliest hominid fossils at that time. Two hominids were identified from sites at Lothagam and Kanapoi dated to 4.4 and 4.1 million years ago. A species name has been coined for them: australopithecus ramidus. Both Leakey in the Lake Turkana and Donald Johanson in the Hadar areas of the Great Rift Valley continue to seek. But Maeve Leakey wrote (1995):
Comparing differences in the genes and blood proteins of humans, chimps and gorillas, molecular biologists estimate that the hominid line split off from other African apes between five and seven million years ago, a time poorly known in the African fossil record.
I knew a site in the Turkana Basin called Lothagam that held sediments of exactly this age. ....
Unfortunately, in five years of collecting abundant animal fossils we found only two possible hominid teeth. I had to conclude that our ancestors between five and seven million years ago preferred a more forested environment.
Or, as I believe, it was during this enormously long time that they were evolving to vertical stance through the potent medium of a semi-aquatic existence on the ocean coast and reef systems. Maeve should change the direction of her search.
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Elaine Morgan was a layperson and few anthropologists or archaeologists seemed to take notice of her aquatic hypothesis. When she published The Aquatic Ape (1982) I saw her on TV promoting the book and appealing to the scientific community to treat the hypothesis seriously. I continued to find her thesis convincing whilst accepting that there were inevitable loose ends, the most spectacular of which was the absence of fossil evidence. That there were no hominid fossils anywhere previous to four million years encouraged the idea of an intermediate semi-aquatic ape by failing to provide any alternative form of ‘missing link’, but proof was missing one way or the other. Where were shore lines five million years ago; where were the strata of long-buried bones? They were possibly far out under the sea if that was a cool period with water locked in the ice-caps. In The Aquatic Ape, Morgan suggested the Afar triangle bordering the Red Sea, but there was a heavy inertia within the scientific community.
Even in 1996, this inertia continued unabated. I was astonished to read in Stringer and McKie’s book, African Exodus, that they dismissed the hairlessness of hominids in one brief paragraph which repeated the easily disputed ideas put forward by Ardrey and Morris in the 1960s. I quote:
The rest [of the body] is nakedness, the remainder of our primate hair having thinned dramatically because our ancestors evolved in hot, unshaded ground on the savannah plains of Africa. In extreme heat, the body is capable of sweating off a maximum of twenty-eight litres of water in a day. Thick hair would have reduced the effects of that cooling and would also have allowed salt, and other wastes to build up in our fur or hair.
As I have pointed out elsewhere, heavy sweating in a dry, hot environment is suicidal without frequent and regular consumption of water, hence the need for marathon runners (modern equivalents of primitive savannah hunters) to have helpers constantly supplying drinks on the roadside. Native African homesteads were always placed within reach of a daily supply of water; if it failed, they moved. In this context, it is also almost never remarked that modern tropical desert-dwellers clothe themselves from head to toe in voluminous garments; protection from the sun is of primary importance in keeping body heat within acceptable bounds. The rich fur of savannah monkeys and baboons, or the thick hair of camels, is never mentioned. A heavy and uncomfortable build-up of salt in fur or hair certainly suggests hairlessness, but this is most likely to have occurred because of frequent immersion in seawater, not through heavy sweating. So many scientists who repeat dogmatic opinions on African conditions do so from an Euro-centric or Americo-centric view. They should live like a baboon for a while.
I have also read that it was considered by scientists that primitive hominids and later early mankind were brown or golden skinned and only in recent centuries have truly black people evolved, principally along the coasts of India where many get their living from fishing in the sea. This is actually quite ridiculous. The blackest people I have met, apart from Indian sea-fishermen, are those who live in the tropics of Africa no matter what their lifestyle may be. Any naked ape living in the tropics without habitual clothing will always be heavily pigmented all over. The exposed faces, hands and feet of African great Apes, monkeys and baboons are uniformly black. Modern brown skinned Africans were the Khoisan race (and those cultural groups with a good mix of Khoisan genes) of the south and Egyptians, Arabs and Berbers of the north. Anthropologists should spend time in the places about which they write.
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In 1987 I was travelling on the coast of East Africa visiting numerous medieval ruins, gathering material for a book on pre-European Indian Ocean trading systems. My travelling companion, a nephew, and I decided to take a week off at Tiwi Beach. During lazy days at the sea shore where the great eastern African barrier reef shelters the white coral-sand beaches I was preoccupied with the ‘aquatic ape’. I reviewed Elaine Morgan’s arguments and my own interpretations and enlargements and tried them out on my nephew. There, in the precise environment where the enormous evolutionary jump may have occurred it was suddenly so obvious and natural. I described the revelation in my book, Two Shores of the Ocean (1992), which I quote for its immediacy:
One morning towards the end of our stay at Tiwi Beach, I was sitting on the verandah as usual after breakfast nursing a mug of coffee. The tide was flowing and water was deepening over the reef. The thunder and roar of the waves breaking on the outer bastion was growing. A holidaying English family was coming home from an early morning exploration to their breakfast, picking their way carefully over the old coral, the children trailing behind the adults and chattering. “Here come the ‘aquatic apes’,” I smiled to myself.
Following the holidaymakers were two dark figures, stopping here and there, moving confidently onwards, then pausing again. They were two local men whom I had seen many times and I idly followed them with my eyes, until a thought burst into my mind that astonished me with its simple and absolute obviousness. Those men went out onto the reef every day and on their return, they passed by our cottage peddling fresh fish and shellfish. I knew them by sight and they always greeted me whether I bought or not. Why had I not seen it? They were aquatic men; there for any doubter to examine. It was not necessary to theorise at Tiwi Beach, intuitive observation provided me with proof.
I watched while they emerged from the sea and strolled up the lawn. Each young man was clad in a brief kikoyi cloth wrapped around his waist and they were burned obsidian black by the sun. Their curly Negro hair glistened with moisture. From a string around their waists was slung a handmade tool, a simple metal spike with a wooden handle that they used to pry shellfish from the rocks, and they carried a roughly barbed trident on the end of a long bamboo pole that they used to spear fish and octopus. A handmade sisal bag hung from their shoulders for shellfish and each had fish strung through their gills by a length of coconut frond. Remove the machine-woven cotton kikoyi and substitute bone or ivory for iron and they were equipped as any aquatic man would have been for a million years, since that last great evolutionary jump.
Despite my conviction, I still had worries. Ancestral chimpanzee-like apes, could have survived successfully in the littoral habitat without suffering such a dramatic sea-change. What forced the massive behavioural change and a huge jump in physical evolution? If the aquatic hypothesis succeeded where the savannah hypothesis failed, then some irresistible imperative must have promoted it.
Despite all the physiological and behavioural arguments, rigorous thought about the changing geography and its effects, and comparisons with our nearest chimpanzee cousins, there was a particular gap in the logical progression. What was the trigger? There had to be a trigger! I feared that the aquatic hypothesis skated over similar failings which I saw in the conventional savannah explanations.
CHAPTER THREE: THE DRIVING FORCE
Michael Crawford was Head of the Department of Nutritional Biochemistry at the Nuffield Institute in London and a professor at Nottingham University. David Marsh was a professional researcher specialising in evolutionary theory. In their book, The Driving Force (1989), they proposed a new look at all biological evolution on Earth, suggesting an added dimension to the Darwinian theory of evolution. They took a close look at the problem of the evolutionary jump from ape to hominid.
The new dimension they proposed was the particular role of nutrition and the physical environment with which it is interlocked. They suggested that random genetic mutation is just one of several factors causing evolution. The environment, which influences nutrition and behaviour in all plants and animals up the food chain, is the dominant factor. All is cause and effect, all is integrated. The environmental habitat governs behaviour which is enormously important to evolution but the DRIVING FORCE is the food that all creatures consume, and food is a vital facet of the environment.
Environmental change, whether induced by climate or because a species migrates, means change to diet and behaviour. Food is the fuel and chemical agent for every minute and obscure activity within living organisms from the simplicity of ancient bacteria to modern mammals. From the moment an ovum is fertilised by a sperm in a mammalian womb, nutrients enter the new living system and eventually a hugely complex, mature animal walks the earth. In the case of a higher primate, like the hominids, this complexity is at its greatest and the maturing process takes years. Two distinct essentials contribute to this miracle: the DNA recipes within the two seminal cells and the nutrition that is fed to the growing and developing animal.
Molecular changes in the genetic controls are caused by nutritional changes and random mutations add to them. Evolution proceeds by jumps when nutrition and environment are favourable and the engine of positive feedback is running. If a change in nutrition is sustained, affecting thousands of succeeding generations, chemical changes to genes in the DNA recipe occur causing permanent changes to the species. The magnitude of the nutritional change determines the potential for biochemical activity and the number of generations experiencing the new diet determine how much genetic change there can be. If there is sufficient time, all genetic changes possible can take place.
But nothing is static, the environment changes as climate changes, species migrate, behavioural adaptations amend diets, natural selection is at work: evolution is continuous.
Without some braking and refining process, there would be a disastrous proliferation of strange forms within the species and unhealthy aberrations. It is here that natural selection and ‘survival of the fittest’ play their essential roles, culling off unfit developments and aiming for stability. It was an exciting addition to Darwinian theory which struck me like a blinding light.
Evolution, Crawford and Marsh repeatedly point out with many examples, progresses often in extraordinary jumps when organisms develop which are able to exploit nutritional surpluses which either occur because prey species are expanding or when competition has been reduced by widespread extinctions. Amazing jumps are usually followed by periods of relative stability with refinement interspersed by minor jumps and extinctions.
The acquisition of more geological and astronomical data recently has improved understanding of recurrent mass extinctions. Whenever they occurred there were opportunities for species that were waiting to expand but unable to do so because the environment had been fully exploited until then by already established species. The vacuum is filled by a spectrum of rapidly expanding and evolving species who complement and interact with each other, aiding both processes of nutritional ‘driving forces’ and natural selection.
The biochemical exposition is complicated but rests, most simply, on the proposition that as life itself becomes more complicated and plants and animals expand in complexity and feed on each other, feeding on other species lower in the chain, they ingest organic matter already developed for specific uses by their prey, whether animal or vegetable. Metabolic effort is not required to chemically build these foods for diverse purposes: organisms can use energies, advanced organic chemicals and DNA resources already in the foods they eat to increase their own complexity. The upward spiral of positive feedback runs ever faster until environmental limits are reached and natural selection operates the brake. The principle of ‘survival of the fittest’ does not stimulate evolution; contrarily, it operates when nutrient-driven and environment-adapted evolution in a stimulating environment is too successful.
A quotation from The Driving Force is appropriate:
We could sum up our approach by saying that we see all life forms and their evolution as examples of physics and chemistry in action. The process can be considered as a series of chemical reactions in which genetics, organisms and their environments interact. Variability occurs in both genetics and chemistry but the evidence indicates that, of the two, chemistry is the more coercive.
Further on in the book, while describing biochemical complexities that favour genetic evolution rather than random mutation from external sources, the authors write:
.... a very simple mechanism can now be proposed which would lead to permanent genetic change. If the introduction of a new nutrient suppresses its synthesis by the cell, it would have the effect of a suppressor sitting on the DNA: just as in cell specialisation. If the new chemical input becomes permanent, then total deletion of the DNA segment would not be noticed. .... if that covered section is rewritten, then new ideas could be expressed in a heritable manner.
Here is one of several examples given:
The conventional view is that the horse achieved its present shape and form through competition to run fast, the slower members being filtered out. We suggest it happened the other way around. Nutrition induced change in form, and genetic change, if and when it occurred, would have operated within the confines already set by nutrition.
Prof. Michael Crawford, in a letter to me, wrote: “The mistake current evolution theory makes is to consider food as food... The evidence we have accumulated in our laboratory clearly shows that there are different nutritional principles (and hence foods) involved in body growth on the one hand and brain growth on the other.”
Crawford and Marsh’s thesis of an aquatic origin for hominid evolution began with the particular study of the biochemical effects of a prolonged seafood diet producing a nutrition-based evolutionary driving force on the brains of land mammals. Conclusions drawn from an examination of dolphins, seals and the other aquatic mammals were at the core of their theory. What fascinated them was that as they developed their argument it increasingly coincided with Sir Alister Hardy’s physiological and behavioural proposals for an aquatic ape phase in human evolution. They came to the specific aquatic ape hypothesis from other, more general studies. An aquatic ape hypothesis was not an objective of the research.
If changes of food and behaviour become reasonably permanent, DNA recipes are altered and evolution surges ahead. Seafood nutrients are the most powerful ingredients in expanding the neuro systems and brains of mammals and an ape who exploited the food of seashores and experimented with a new lifestyle under stress of climate-induced environmental change could enter an exploding phase of positive feedback. The biochemical detail of this argument, that seafoods are the most powerful neural building blocks for higher orders of mammals with large brains, such as whales, dolphins or apes, is complex. But it has been subject to extensive research. Its application to concepts of evolutionary jumps leading to aquatic apes is the novelty provided by Crawford and Marsh.
Any mammal which has had a sustained seafood diet over a prolonged period of time undergoes profound physical and behavioural change. The examples are numerous, besides the obvious ones of the ocean-going mammals such as whales and dolphins. Different species of the seal, sealion, dugong and otter families are aquatic or semi-aquatic forms of land mammals which have adapted to the oceans. Crawford and Marsh propose that the relatively great changes these species made were stimulated by nutritional driving forces.
I believe that all of the anatomical and behavioural jumps to a vertical, naked, socially complex hominid could have occurred on the eastern African littoral through the driving force of new seafoods in an abundant habitat. It was a massive infusion of suitable nutrients over a long period that was the trigger and the ‘driving force’. In this particular context, ‘a long period’ could be something like one or two million years.
Ancestral mankind did not evolve to become rather inefficient hunters in competition with big cats and packs of dogs, they did not walk upright because they ‘needed’ to carry tools and weapons around on the highveld. They certainly did not ‘need’ to become naked and develop a heavy sweating mechanism in a dry climate. They became semi-aquatic and evolved power-house brains because they ate lots of seafood and lived in and around the tropical reefs of eastern Africa. The carrying of tools and the results of fishing and shellfish gathering on coral reefs was the obvious path to needing free hands and the invention of carry-bags. Frequent immersion in seawater and the problem of dried salt, sand, shells and seaweeds in their hair made them naked. Ducking and diving in the sea changed their breathing equipment and allowed them to produce an extended range of sounds.
All the other behavioural and environmental factors played their powerful roles. Positive feedback was the engine, seafoods were the fuel, the littoral environment was the anvil and natural selection was the refining process. The link in logic that had bothered me was in place.
Besides the evidence involving nutrition as a ‘driving force’ and ‘survival of the fittest’ as the refining process, I had another clue about the, apparently non-connected, logic of this concept. Lyall Watson in Dark Nature (1995) explores the role of genes and learned behaviour in the apparent dichotomy of ruthlessness and altruism in animals in the complete range of complexity from the simplest to the most complex. He cites many examples of the ‘driving force’ of genes which selfishly use the bodies of their hosts, the animals of the species of which they are the physical blueprint, and the altruistic and unselfish behaviour of the same species which animals learn to survive in a social environment. Those learned altruistic traits then, presumably, became feed-back to the genes altering their design and a most complex creature evolves.
The ‘driving force’ here is the imperative of the gene to survive by ruthless self-seeking to the supreme limits of forcing the host animal to commit fratricide, infanticide and conditioned cannibalism: the classical Darwinian concept of ‘survival of the fittest’. However, the apparent malevolent, single-minded behaviour of the gene has to be tempered by a brake otherwise the species as a whole could become extinct. This is provided by a complex set of learned behaviours which favour cooperation within a species, promoting the survival of the species as a whole as well as the promotion of individuals. The gene must also accommodate these behavioural rules which seemingly contradict the basic ‘driving force’. The evolution of the brake must have occurred and continues to do so through a secondary process of ‘survival of the fittest’, refining the whole organism and its genes.
A universal logic begins to emerge, and I increasingly see this applicable to all questions about life. Perhaps it is basic to our Universe, maybe it is essential to any anthropomorphic universe? Maybe our Universe is anthropomorphic because this is the evidence for it?
* *
The story is nowhere complete, however. I had come to believe that there are universal laws governing the evolution of life on Earth. I had come to believe that the evolution of a possible ramapithecus-type or Kenyapithecus-type forest fringe ape to an ‘aquatic ape’ to australopithecus happened as I have described it. I saw the geographical routes that the earliest australopithecus hominids probably took to move inland along rivers to colonise the Great Rift Valley lakes, other lakes and river systems in the far interior such as the Chad region and the South African highveld. But I was not sure whether that migration inland would have been logical for, after all, considerable physical and social evolution had occurred to adapt to a seashore existence. A naked, vertical hominid happily living a semi-aquatic seashore existence would have to have been stimulated by a severe environmental change to embark on such a dangerous course.
There are the other air-breathing animals of terrestrial origin which have maintained aquatic lifestyles. The biochemical evidence for the ‘driving force’ particularly applicable to the physical development of large brains in mankind comes from the detailed study of aquatic fish-eating mammals, especially dolphins. Fish-eating whales and dolphins adapted completely whilst others such as the seal family still come onto land for recreation and, especially, for breeding. There are other aquatic members of air-breathing land-breeding families across the whole spectrum of animal life such as hippos, beavers, otters, penguins, duck-billed platypuses, terrapins, turtles, snakes and crocodiles. This spectrum also extends over tens of millions of years and goes back beyond the separation of the continents by tectonic drift.
The land-water interface is complex. Our ancestors only partially embraced an aquatic lifestyle and we are dependent on the land now, no matter how much we adore the sea and water and are driven to catch and eat fish. So, a dramatic event had to interrupt our progress.
Elaine Morgan in The Aquatic Ape (1982) suggested that the aquatic ape evolved on islands off the Ethiopian coast when portions of north-east Africa were submerged. When the land rose during collision between the African and Arabian plates, australopithecus hominids migrated south into the chain of lakes of the Great Rift Valley. She uses a paper by Leon La Lumiere Jr of the U.S. Naval Research Laboratory to support this geological concept. This idea supplies the necessary stimulus for aquatic apes to reverse their evolutionary path and spread over land as australopithecus. But it assumes an extended process in a timescale of gradual geological change. Zoologist and anthropologist Lyall Watson in Earthworks (1986) also found difficulty with this idea and suggested that fossils of the aquatic ape will be found in the eroded walls of river valleys near the sea all down eastern Africa. He had an intuitive feeling for the Zambezi valley.
I had discarded Morgan’s idea of an origin on an ancient island off the Red Sea shores and migration caused by a collision of the African and Arabian plates. She seemed to me to have been trapped by a conventional view of massive evolution needing massive timespans of natural selection, which fitted her solution. Since she wrote, Richard Dawkins’ thesis in The Blind Watchmaker (1986) showed that significant genetic mutation could move rapidly in time of the order of tens of thousands of years under a sufficiently powerful sustained stimulus, which Crawford and Marsh’s nutritional ‘driving force’ could help to provide.
Instead of millions of years of gradual progress in evolution which was classical theory, I saw short sharp jumps caused by environmental shocks with intervening stable periods of consolidation and refinement when natural selection weeded and pruned. It was not the idea of aquatic apes evolving on offshore islands and reefs that worried me, it was an extended geological timescale determined by the movements of continental plates. Elephants migrate in the face of short-term droughts of a few years or the flooding or drying of lakes and swamps, why should australopithecus need a half million years of creeping plate tectonics to shift off an island?
Hundreds of thousands of thousands or a million years, may have been necessary to push an ancestral forest ape towards the physical evolution of large brains, vertical stance, hairlessness and so forth under the stimulus of eons of seafood nutrition. But that order of time is unnecessary to switch from an ocean-shore environment to a riverine or lacustrine lifestyle. That relatively minor adaptation would require a much shorter time, perhaps only a dozen generations. The adaptation would not have been physiological, it would have been behavioural. Physiological evolution following that behavioural change resulting in a new environment with new nutrition could then follow during long term residence in that new environment with its new nutrition. Australopithecus fossils have been found in places from Chad to South Africa, mostly in the Great Rift Valley, dated from more than four million years ago. In that enormous time span away from the ocean, and also beside it, we have changed in various jumps and minor extinctions to modern homo sapiens.
It is also becoming increasingly clear from the evidence of fossil australopithecine bones of hundreds of different individuals, from South Africa and all along the line to the Red Sea coast, that there was a wide variety amongst individuals living in the collection of habitats to be expected over such a continental range. These fossils are from a period of two million years or more, a relatively enormously long period. Scientists are devising what may be seen one day as an unnecessary number of species to account for these differences. To date, there are at least seven recognised species of the genus and one wonders whether they were merely races or at most sub-species. Were they capable, or interested, in miscegenation; the usually-accepted means for constraints in species diversification?
It is necessary to remind oneself of the physiological differences between modern San-Bushmen of the Kalahari desert, Pygmies of the Congo Basin rainforests, cattle herders of the southern Nile region, industrial workers of northern Europe or rice farmers of the Mekong delta in southeast Asia. They are all definitely homo sapiens, with lesser genetic divergences over the whole planet than can be found in modern chimpanzees or gorillas in their relatively tiny homelands.
Personal ambition may be playing its part and one way to obtain professional status is to name a new species and propose substantially different behaviour and development for your ‘discovery’. Rick Gore writing in the National Geographic in February 1997 states: “Such disagreement over bones is intense. I have seen the faces of distinguished scientists flush as they’ve bashed one another’s theories about the anatomy of [australopithecus] afarensis with acerbic words.”
The East African seashore level is, I believe, much as it might be during any warm climatic cycle such as we are presently experiencing. When the climate was cooler with water locked into northern hemisphere glaciers and an extended Antarctic polar cap, the sea level was lower with coral reefs and islands further out in the ocean than present shorelines. But sea levels have also been higher than at present, or the land lower. At Tiwi Beach there are two levels of old coral reef plainly visible on land whose highest crest rises to maybe 100 feet above sea level and as one drives inland anywhere on the Kenya coast, the lines of old reefs are crossed. Coral is quarried for a cement factory near Mombasa. East Africa has seen many different ocean levels.
I dismissed the extreme gradualism of geological time as the motive for the migration of australopithecus to the Great Rift Valley lakes, Lake Chad and the interior of far South Africa. I also saw that these migrations may have happened several times, resulting from relatively temporary stimuli and regressions; there was no simple linear progression and there had to be other factors. Perhaps the explanation is the simplest one; as climate fluctuated and conditions on the eastern African littoral varied, populations also fluctuated. When there was exceptional growth, there were migrations. Some migrants succeeded in establishing themselves in the interior, others failed. Some settlements flourished for periods of a few thousand years. Eventually, there were permanent populations. Climate was the dominant factor until the hominid line’s brain and nervous system evolved further in the seashore environment, with the stimulus of its special seafood nutritional driving force, and could dominate climatic change.
The apparent proliferation of races, sub-species or species presently being found in inland sites could simply be the result of different migrations to those regions from a gradually changing core population of semi-aquatic hominids along the tropical seashores from the Red Sea to the Zambezi or even further southwards. The time span of two million years and the rigours of natural selection in differing inland climates at different periods and in different habitats could provide regional skeletal changes without resulting in divergent speciation of the core people on the Indian Ocean coast.
* *
Following genetic protein markers, scientists satisfied themselves that the line of gorillas and chimps separated from ours between five and ten million years ago. The discovery of australopithecus fossils in the Turkana region dated from four or more million years ago sets a clear beacon in time. By then the jump from ape to upright, bipedal hominid had already happened and our line had moved radically away from the evolutionary plateau of our surviving forest cousins. Coincidentally, other ape varieties became extinct as the rainforests declined and monkeys expanded to fill niches.
If a successful aquatic ape had evolved by maybe five million years ago it could be assumed that further progress might have moved towards a hominid version of the seal. Whales, dolphins and seals have been aquatic fish-eating mammals for millions of years: the only challenges they have faced in eons are slaughter by humans and the pollution of sea waters by modern civilisation. So, another kind of challenge was necessary for the aquatic ape to undergo behavioural evolution to land-roving mankind. What happened at about four-five million years ago?
By chance I read a report on the dating of ferns, tree stems, roots and pollen found high on Antarctic mountains which suggested that for a period at about four million years ago, during the late Pliocene epoch, the Antarctic had been warmer and much of its ice had melted. This was an interesting idea and the concept of a boringly stable, endlessly cool dry Earth in the Pliocene was a myth. Perhaps this happened many times during the Pliocene, or frequently during a segment of that era. The oceans would have been much higher and shorelines in eastern Africa would have been far inland. It is a feature of eastern African geography that from Somalia to Natal there are wide low-lying plains stretching inland for as much as two or three hundred miles in places.
Dr Dave Marchand, one of the presenters of a Horizon documentary on BBC TV in November 1997, showed how latest geological exploration of Antarctica indicates that following the break-up of Gondwanaland by magma plume upwellings the new Antarctic continent had suffered a number of changes in ice coverage with consequent planetary ocean level fluctuations over tens of millions of years. The western Antarctic is geologically unstable and between 4-3,000,000 years BP there were plants growing there. At that time, ocean levels were considerably higher than today.
The aquatic apes, developing to the stage of an australopithecus hominid, would have found their coastal habitat in flux. They were not merely forced to migrate inland or back as sea levels changed. That would be easy to accommodate. The problem would surely have been that there must also have been dramatic climatic changes following dramatic shifts in global temperatures illustrated by the particular event of about four million years ago. Rainfalls varied and vegetation changed. Islands were swamped and land features became new islands.
Great changes in ocean levels and the size of the Antarctic ice-cap could cause world-wide changes in ocean currents and the Indian Ocean monsoon weather systems. Chaos reigned in terms of thousands of years, not noticeable within generations, but sufficient to stimulate new social and economic activity promoting movement and evolution. Nutrition changed, natural selection pressures changed, new behaviour was forced. Who knows what happened to the environment of the eastern African littoral?
Widespread climatic changes could have been the trigger to promote australopithecus, still dependent on the land though strongly oriented to the sea, to roam across the eastern African savannah, following rivers. The nomadic lifestyle began and perhaps became genetically imprinted; nomadism is another dominant trait of mankind, often given little attention. Maybe the coastal forests died back and then became exceptionally lush in quite short cycles promoting alternating need to move out because of famine or because of population growth. If it is conventionally accepted that widespread drying out of central Africa promoted the evolution from forest ape towards a savannah-dwelling australopithecus, then it is not unreasonable to suggest that severe climatic change stimulated an intermediate species of ocean-oriented semi-aquatic ape to roam the rivers and lakes of the interior. Later, when ice-age cycles became more clearly established, perhaps resulting in the evolution of the homo line, nomadism is more closely seen as a human trait.
Lucky nomads found freshwater aquatic systems around the string of great lakes of eastern Africa. Some survived along the Great Rift Valley rivers of Ethiopia. Some went further to colonise the Nile and the lake and river systems of central and western Africa, others moved up the Zambezi and Limpopo rivers of southern Africa and left their remains in the famous limestone caves of the Transvaal. Populations could have fluctuated wildly and sub-species became extinct. Others, the core, stayed beside the sea, learning to cope with the very changes forcing others into continent-wide nomadism and accommodated themselves to the changes. They were, I believe, the most likely ancestors of the true homo line. Their fossils may also never be found, particularly if nobody looks for them.
However, the search does continue intermittently. Tim Bromage and Friedemann Schrenk found a hominid jawbone and other fossils in the Great Rift Valley near the shore of Lake Malawi in 1991/92. These bones have been dated to about 2.3M years before present. Prof. Phillip Tobias, who worked with Louis Leakey on the first early hominid discoveries in Tanzania and was a colleague of Raymond Dart, has described the jawbone as probably that of homo habilis, the earliest of its line so far found. He was quoted in the Johannesburg Star of 29th October 1993: “What is exciting about the new discovery ... is that their discovery falls in the no-man’s-land between the Transvaal hominid sites and Tanzania. It is very exciting geographically...”
Anita Allen wrote in the Johannesburg Star on 12 August 1996 about a discovery in the Sahara.
It was the first time that a fossil of the apemen Australopithecus had been found west of the Rift Valley. In this case 2,500km west near the town Bahrelghazal, meaning “River of Gazelles” in Arabic.
Four million years ago, the region was a great inland lake. Where Lake Chad covers 25,000sq kms today it was once 800,000sq kms and 1,000kms wide. ...
The jaw of a young adult hominid was found half buried in the desert sand by paleo-anthropologist Professor Michel Brunot of the University of Poitiers, after a twelve year search in north-western Africa. ...
... Professor Yves Coppens of the College des France has worked there [western Africa] since the 1960s, and already a fossil of man’s own group, Homo erectus, has been found.
“It’s quite clear that the Eastside story - that man’s origins lie in the Rift Valley - is not correct. ...” [Coppens said].
We are not at the end of that story. But the Leakeys, Johanson and now these French scientists still persist in seeking answers in the forests. Professor Brunet is quoted: “But we are sure now that Australopithecus is largely represented all around dense forests of Africa between 3 to 4 million years ago.”
Tim White of Berkeley, California, and his colleague Berhane Ashaw, have named an early hominid whose fossils they discovered in the Rift Valley in Ethiopia, ardipithecus ramidus, maintaining that it is of a new genus, pre-dating australopithecus. Rick Gore in National Geographic quotes White: “Let’s just say ramidus had a type of locomotion unlike anything living today.” But, nor did any of the australopithecines! White guards his fossils jealously.
Philip Tobias, Ron Clark and Lee Berger of the University of the Witwatersrand in Johannesburg, reviewing their hundreds of bones from the South African sites, contemplate the possibility that australopithecus first emerged on southern African plains during a declining forested period and migrated north along the Rift Valley. In South Africa new fossils arrive in the public view almost routinely. The “Little Foot” fossil find was published in 1995. In 1998, Ron Clarke and his indefatigable team revealed their discovery of an almost complete skeleton, dated about 3.5M years ago, in the Sterkfontein caves. It is fascinating; yet these late discoveries are still nothing more startling than examples of the familiar australopithecus.
And so the controversy continues, without any serious thought being given to an ocean littoral environment which would change all existing scenarios. It is remarkable how the aquatic hypothesis eludes them all.
* *
If the seaside aquatic ape hypothesis is to be overturned, then it could only be by a freshwater hypothesis, which is sustainable because most fossils have been found along the Rift Valley. I would have to accept that the critical turning point occurred on the shores of the great African lakes rather than by the Indian Ocean. Stringer and McKie show that there has been serious thought given to the nutritional ‘driving force’ of meat in the development of the evolution of later hominids, which would have a similar if rather lesser neurological stimulus than seafoods. Much high-protein freshwater fish consumed in a lacustrine environment would also suffice as a powerful ‘driving force’. It can be argued that earliest hominids were a small and insignificant population spread thinly along the shores of lakes and rivers of the Great Rift valley who gradually explored and spread as evolution, with the push of high-protein diets, gave them better brains and technology. This fine cover of few dispersed creatures would explain the difficulty in finding them in the fossil record. Vertical stance could have evolved from living a semi-aquatic lifestyle beside the lakes. Not so different to the seaside hypothesis?
But what about nakedness? What about our specific and different sexual culture, following from nakedness. What about the competition from freshwater crocodiles and the threat of ever-present cats and dogs? What about eccrine sweating, a most difficult and usually-ignored problem? Much thought and integrated investigation could be devoted to these theses. I can contemplate this, but I have neither the research facilities and library to extend it, nor the desire to expend the necessary time at this time of my life.
I prefer a seaside scenario, because all the questions seem to be answered. But, a lakeside scenario is almost as good. Indeed, there could have been evolution in both environments and some of the questions could be resolved by mixing of culture and genes between the two similarly adapted groups, and the subsequent emergence of a rash of sub-species of australopithecines.
This is a most serious line of investigation.
The success of these aquatic apes, whether from the seaside or lakeside, from both, or a merging of them over hundreds of thousands of years, can be seen in their successful spread over much of Africa.
The problem of the apparently separate emergence of the homo line remains however and here there is another ‘missing link’ in the fossil record.
* *
Elaine Morgan’s lonely persistence continued and she brought out a third book, The Scars of Evolution (1990), in which she reviewed the arguments once again and once again updated them with her thinking during the intervening years and included new information and discussion. I was sorry to notice that she gave minimal attention to Crawford and Marsh’s nutritional ‘driving force’.
The most important new information was evidence of a genetic aberration called the ‘baboon marker’, discovered by Todaro, Sherr and Benveniste of the National Cancer Institute at Bethesda, Maryland. This was the result of an ancient virus epidemic originating in baboons which must have decimated or destroyed some primate populations in Africa at some unstated period in the distant past. Elaine Morgan summarised the ‘baboon marker’:
The infectious type C virus ..... belongs, like the AIDS virus, to the class known as retroviruses. When such a virus infects an animal, the RNA of the virus is converted to DNA inside the cells. This means that it becomes part of the genetic make-up of the infected animal......
The type C virus is endogenous only in baboons - that is, it is a normal part of their make-up and has no effect on them. But when it crosses the species barrier it has the potential to cause disease in other primates. Tests showed that every modern African monkey and ape has the ‘baboon marker’, but it does not exist anywhere else on Earth and does not exist in humans.
A simple conclusion is that some time after ancestral hominids split away from the gorillas and chimps some at least must have migrated out of reach of the type C virus and, when it had become harmless through extinction or mutations, they returned to Africa. Presumably, those that had not migrated out of reach at that early stage did not survive, or their descendants did not survive. This is an extraordinary piece of information, all the more amazing for not being the subject of wide and excited discussion of human origins.
If there is one simple and conclusive argument disputing the African savannah-ape origin for mankind, it has to be the ‘baboon marker’ waiting for protagonists and opposition to marshal their ideas. The ‘baboon marker’ would also need investigation if a lacustrine aquatic ape scenario was to be considered as the only pathway of hominid evolution. It suggests that an exclusively seaside period was inevitable at some time in our past.
Morgan uses the ‘baboon marker’ to reinforce her thesis that the aquatic ape evolved in isolation on Danakil Island, separated from the Red Sea coast. When the colliding African and Arabian plates disturbed the Afar triangle, she maintains, the aquatic ape, by now evolved to australopithecus, began spreading down the Rift Valley and as far as South Africa. The scourge of the type C baboon virus must have spread and then lost its virulence during the jump through the aquatic ape phase on Danakil Island.
Morgan’s explanation for hominid survival is perfectly reasonable if one accepts the Danakil event. My objections to that remain unchanged. I believe that the aquatic ape phase occurred along an equally geographically restricted zone, but much larger: the length of the eastern African ocean littoral. I believe that migrations into the heart of Africa were caused by widespread climatic fluctuations rather than the grinding together of the continental plates in a geological timescale. In order to account for the absence of the ‘baboon marker’, it is necessary to assume that when the virus was sweeping Africa the aquatic apes who survived were living on a chain of islands along reef lines off the eastern coast. There are any number of islands today and though seashores have moved, perhaps dramatically, in the last five million years, there is no reason why they were not equally or more numerous then. Seashores with oceanic winds (the monsoons) could have restricted the effect of air-carried viruses.
There must have been connection with the mainland. Those that lived there or had contact with its shores must have been infected and died or failed to reproduce. Who knows what effect the virus had on aquatic apes, or australopithecus hominids? It certainly would have acted with a devastating effect of ‘survival of the fittest’. Perhaps the offshore aquatic apes learned that they must stay on their islands and reef systems for the duration of the plague, because all those contacted died prematurely. And since this baboon virus is presumed to have been air-borne, unlike the HIV viruses, since it spread to every known African primate, monkey and ape, that duration may have been short, maybe as short as a few hundred years. We all hope that the HIV viruses will mutate away in a matter of some decades, or a century or two; otherwise we seem doomed.
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Presumably, after the baboon virus may have lost its virulence and mutated, there were two coexisting groups of hominid species in Africa for hundreds of thousand of years. There were the australopithecines and the early ‘true’ homos: homo habilis and their direct successors, homo erectus. The differences between the two lines are substantial. Australopithecus, though bipedal, were smaller and did not have a pelvis suited to long marches across the land which later homos developed. They used tools of wood, bone and suitable stones but they did not make them, and their brains, though larger than their ape cousins’, were still small.
Raymond Dart, the pioneering South African palaeontologist, proposed that bones and horns were used as tools long before stones. He was passionate in this belief supported by numerous bones found with australopithecine remains at Makapansgat and elsewhere. Bones, whether found on the veld or discarded in a midden, present a great variety of possible uses without much alteration, if any, whereas a stone tool has to be imagined within the natural lump of rock.
The divergence of the true homo line was conventionally thought to have developed in parallel by a mechanism of species deviation. They first appear in the fossil record about two and a half million years ago and, in parallel, australopithecus types continued to survive in places for another million years or so before disappearing. Fierce thought and debate continues to explore these events since there is no clear evidence yet from the fossil record where and how it all happened.
I suggest that the reasoning for the divergence is simple. Australopithecus evolved on the seaside, and other aquatic environments, and expanded inland following a period of climatic upheavals about four to five million years ago. The homo line continued to evolve on the ocean littoral and offshore islands.
In the more rigorous environment of the interior, the brake of natural selection took control and differences between australopithecine species, sub-species and races emerged in separate ecological niches across the interior. Palaeontologists have defined them from the earliest, ramidus from north of Turkana and a.afarensis from the Afar region of Ethiopia (Morgan’s preferred domain of the aquatic ape) through the ‘gracile’ a.africanus of Dart’s first discovery in South Africa, to the later more robust types, a.robustus and a.boisei, defined by Louis Leakey in East Africa. Which of these australopithecine species or races divided or progressed from which continues to be the bones of fierce contention between palaeanthropologists.
Donald Johanson, discoverer of a.afarensis, long maintained that this smallest and most primitive of the family so far discovered was probably the earliest true hominid from which all other australopithecines and the homo line descended. Maeve Leakey’s later revelation of earlier fossils of a distinct type illustrates the proliferation of early hominids in different environments during this seminal period.
Tim White, of the University of California, believed that his discovery, ardipithecus ramidus, in Ethiopia is closer to the ‘missing link’ because it has more ape-like features than australopithecus and a smaller brain, but had vertical stance. Evaluation continues.
‘Survival of the fittest’ was steadily at work and australopithecus’ evolutionary progress was halted. Physically changed enormously by the jump through the semi-aquatic phase, they were sadly trapped in the savannah to which they were not suited with their naked skins, heavy sweating and imperfect command of the environment. Their brains were insufficiently developed to be capable of sophisticated toolmaking or abstract language. That they survived as long as they did can only be because the riverine and lakeside habitats which they found were adequate.
Clearly defined cyclical Ice-ages (and warm interglacials) began about 2.5 million years ago and a series of minor extinctions and stimulations of all mammals began which continues to the present. The australopithecines who had migrated inland and settled near water with changed diet survived these shocks with difficulty despite regional divergence into more robust forms. They had not developed toolmaking to the point where they could make clothing to cover their naked bodies and they had not domesticated fire. The last of them became extinct between one and 1½ million years ago.
But it is unreasonable to assume that all moved away from the seashore. Many could have remained in the shifting coastal habitats and their consumption of seafoods with its nutritional driving force continued with vigour for another one to two million years. Evolution of the brain amongst the coastal australopithecines persisted whilst their cousins who had moved to the Rift Valley struggled and stagnated. The genetic and behavioural gulf widened. The stimulus of the dynamic seafood diet on thousands of succeeding generations resulted in the huge brain of the true homo line together with other interrelated changes.
During an extended sojourn by the Indian Ocean, the seaside australopithecines would have improved their swimming and diving techniques which stimulated the further straightening and strengthening of their legs and pelvic structures which coincidentally improved walking and running ability. Continued changes in their air passages and larynx, with perfected breath control to make diving easier, enhanced talking and language to take advantage of the bigger brains. Continued swimming and diving improved lungs and chests giving them greater stamina for long marches and sustained running which enhanced hunting ability on land. The fossil evidence suggests these anatomical changed. Positive feedback and interaction continued.
Diverse tool-making began, communication became more sophisticated and reasoning ability to solve abstract problems developed. As numbers increased during particularly favourable periods, warm interglacials, they also began exploring up those rivers which their ancestors had followed. They learned to control fire and use skins and suitable vegetable materials to make clothing with their improved tools. Regular hunting was pursued to provide clothing in cooler highland and sub-tropical zones and efficient carry-bags for their slow-maturing babies and tool-kits on the march.
Perhaps the need for skins promoted organised hunting and not the other way round? Modern Africans, even those who own massive cattle and goat herds, rely on a vegetarian diet for basic survival. Meat eating was always a luxury and often part of religious ritual in Africa. Some herding cultures today, such as the Masai, do not eat wild meat. The Zulu kings of South Africa in the 19th century organised hunting principally for skin, fur and feathers to decorate the distinctive uniforms of different regiments of their standing army. Sanctioned annual or periodic hunting for meat was often part of a religious or important social celebration.
Who knows what varied environmental encouragements were provided by the Ice-age cycles, building on the seafood nutritional driving force of another one or two millions years? The dynamic of the evolution of the homo line was achieved.
Probably homo habilis was the first new migrant from seashores to the interior, followed by homo erectus after another period of development along the ocean littoral. There is no clear fossil record to illustrate the appearance of homo habilis or erectus in the interior of East Africa; there is another ‘missing link’ in the story. Palaeontologists, frustrated with their inability to prove the origins of the first hominids, increasingly are turning to the study of this next ‘missing link’.
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The first hominid to migrate into the interior, australopithecus, spread and diverged into different forms and this process could have been repeated by the homos after another two million years by the sea. There were many new challenges to face with the switch to a nomadic life across the land. Coincidentally, the series of Ice-ages and warm interglacial periods that persist to the present had begun. Various fossils of both types and subtle variations between were deposited in the famous sites along the Great Rift Valley.
Maybe the australopithecines had the ‘baboon marker’? Maybe that plague swept Africa after they migrated inland and did not infect the littoral and offshore races who continued to be driven by the seafood diet? Maybe the baboon plague retrovirus in the australopithecines’ DNA inhibited their development and contributed to their extinction? Perhaps it will be possible one day to extract enough complete DNA molecules from the many fossil bones now available to carry out sophisticated analysis and these mysteries will be resolved.