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THE HUMAN FAMILY TREE

The rise and fall of the third chimpanzee

Several branches of our family tree have become extinct, including those belonging to the robust australopithecines, Neanderthals, and possibly a poorly understood 'Third Man' and an Asian population contemporary with Neanderthals. Some descendants of Homo habilis survived to evolve into modern humans. To recognize by different names the changes in fossils representing this line, they are somewhat arbitrarily divided into Homo habilis, then Homo erectus appearing about 1.7 million years ago, and Homo sapiens appearing about 500,000 years ago. A. stands for the genus name of Australopithecus, H. for Homo.

All the developments that I have been discussing so far were played out within the continent of Africa, to which our closest living relatives (the chimps and gorilla) are still confined. The shakedown had left Homo erectus as the sole proto-human on the African stage. Around one million years ago Homo erectus expanded his horizons. His stone tools and bones show that he reached the Near East, then the Far East (where he is represented by the famous fossils known as Peking Man and Java Man) and Europe. He continued to evolve in our direction by an increase in brain size and in skull roundness. By around 500,000 years ago, some of our ancestors looked sufficiently like us, and different enough from earlier Homo erectus, to be classified as our own species (Homo sapiens, meaning 'the wise man'), though they still had thicker skulls and brow ridges than we do today.

Readers unfamiliar with details of our evolution might be forgiven for assuming that the appearance of Homo sapiens constituted the Great Leap Forward. Was our meteoric ascent to sapiens status half-a-million years ago the brilliant climax of Earth's history, when art and sophisticated technology finally burst upon our previously dull planet? Not at all: the appearance of Homo sapiens was a non-event. Cave paintings, houses, and bows and arrows still lay hundreds of thousands of years off in the future. Stone tools continued to be the crude ones that Homo erectus had been making for nearly a million years. The extra brain size of those early Homo sapiens had no dramatic effect on our way of life. That whole long tenure of Homo erectus and early Homo sapiens outside Africa was a period of infinitesimally slow cultural change. In fact, the sole candidate for a major advance was possibly the control of fire, of which caves occupied by Peking Man provide one of the earliest indications in the form of ash, charcoal, and burnt bones. Even that advanceif those cave fires really were man-lit rather than naturalwould belong to Homo erectus, not Homo sapiens.

Thus, the emergence of Homo sapiens illustrates the paradox discussed in Chapter One, that our rise to humanity was not directly proportional to the changes in our genes. Early Homo sapiens had progressed much further in anatomy than in cultural attainments along the road up from chimpanzeehood. Some crucial ingredients still had to be added before the Third Chimpanzee could conceive of painting the Sistine Chapel.

How did our ancestors make their living during the one-and-a-half million years that spanned the emergence of Homo erectus and Homo sapiens'?

The only surviving tools from this period are stone tools that can charitably be described as very crude, in comparison with the beautiful, polished stone tools made until recently by Polynesians, American Indians, and other modern stone-age peoples. Early stone tools vary in size and shape, and archaeologists have used those differences to give the tools different names, such as 'hand-axe', 'chopper', and 'cleaver'. These names conceal the fact that none of those early tools had a sufficiently consistent or distinctive shape to suggest any specific function, as do the obvious needles and spear-points left by the much later Cro-Magnons. Wear-marks on the tools show that they were variously used to cut meat, bone, hides, wood, and non-woody parts of plants, but any size or shape of tool seems to have been used to cut any of those things, and the tool names applied by archaeologists may be little more than arbitrary divisions of a continuum of stone forms.

Negative evidence is also significant here. Many advances in tools that appear after the Great Leap Forward were unknown to Homo erectus and early Homo sapiens. There were no bone tools, no ropes to make nets, and no fishhooks. All the early stone tools may have been held directly in the hand; they show no signs of being mounted on other materials for increased leverage, as we mount steel axe-blades on wooden handles.

What food did our early ancestors get with those crude tools, and how did they get it? At this point, anthropology textbooks usually insert a long chapter entitled something like 'Man the Hunter'. The point here is that baboons, chimps, and some other primates occasionally prey on small vertebrates, but recently surviving stone-age people (like Bushmen) did a lot of big-game hunting. So did Cro-Magnons, according to abundant archaeological evidence. There is no doubt that our early ancestors also ate some meat, as shown by marks of their stone tools on animal bones and by wear-marks on their stone tools caused by cutting meat. The real question is: how much big-game hunting did our early ancestors do? Did big-game hunting skills improve gradually over the past one-and-a-half million years, or was it only since the Great Leap Forward that they made a large contribution to our diet?

Anthropologists routinely reply that we have been successful big-game hunters for a long time. The supposed evidence comes mainly from three archaeological sites occupied around 500,000 years ago: a cave at Zhoukoudian near Beijing, containing bones and tools of Homo erectus ('Peking Man') and bones of many animals; and two non-cave (open-air) sites at Torralba and Ambrona in Spain, with stone tools and bones of elephants and other large animals. It is usually assumed that the people who left the tools killed the animals, brought their carcasses to the site, and ate them there, but all three sites also have bones and faecal remains of hyenas, which could equally well have been the hunters. The bones of the Spanish sites in particular look like they came from a collection of scavenged, water-washed, trampled carcasses such as one can find around African water-holes today, rather than from a human hunters' camp. Thus, while early humans ate some meat, we do not know how much meat they ate, nor whether they got the meat by hunting or scavenging. It is not until much later, around 100,000 years ago, that we have good evidence about human hunting skills, and it is clear that humans then were still very ineffective big-game hunters. Human hunters of 500,000 years ago and earlier must have been even more ineffective.

The mystique of Man the Hunter is now so rooted in us that it is hard to abandon our belief in its long-standing importance. Today, shooting a big animal is regarded as an ultimate expression of macho masculinity. Trapped in this mystique, male anthropologists like to stress the key role of big-game hunting in human evolution. Supposedly, big-game hunting was what induced proto-human males to cooperate with each other, develop language and big brains, join into bands, and share food. Even women were supposedly moulded by men's big-game hunting: women suppressed the external signs of monthly ovulation that are so conspicuous in chimps, so as not to drive men into a frenzy of sexual competition and thereby spoil men's cooperation at hunting. As an example of the purple prose spawned by this men's locker-room mentality, consider the following account of human evolution by Robert Ardrey in his book African Genesis: In some scrawny troop of beleagured not-yet-men on some scrawny forgotten plain a radian particle from an unknown source fractured a never-to-be-forgotten gene, and a primate carnivore was born. For better or worse, for tragedy or for triumph, for ultimate glory or ultimate damnation, intelligence made alliance with the way of the killer, and Cain with his sticks and his stones and his quickly running feet emerged on the high savannah. What pure fantasy!

Western male writers and anthropologists are not the only men with an exaggerated view of hunting. In New Guinea I have lived with real hunters, men who recently emerged from the Stone Age. Conversations at campfires go on for hours over each species of game animal, its habits, and how best to hunt it. To listen to my New Guinea friends, you would think that they eat fresh kangaroo for dinner every night and do little each day except hunt. In fact, when pressed for details, most New Guinea hunters admit that they have bagged only a few kangaroos in their whole life.

I still recall my first morning in the New Guinea highlands, when I set out with a group of a dozen men, armed with bows and arrows. As we passed a fallen tree, there was suddenly much excited shouting, men surrounded the tree, some spanned their bows, and others pressed forward into the brushpile. Convinced that an enraged boar or kangaroo was about to come out fighting, I looked for a tree that I could climb to a perch of safety. Then I heard triumphant shrieks, and out of the brushpile came two mighty hunters holding aloft their prey: two baby wrens, not quite able to fly, weighing about a third of an ounce each, and promptly plucked, roasted, and eaten. The rest of that day's catch consisted of a few frogs and many mushrooms.

Studies of most modern hunter-gatherers with far more effective weapons than early Homo sapiens show that most of a family's calories come from plant food gathered by women. Men catch rabbits and other small game never mentioned in the heroic campfire stories. Occasionally the men do bag a large animal, which does indeed contribute significantly to protein intake. But it is only in the Arctic, where little plant food is available, that big-game hunting becomes the dominant food source, and humans did not reach the Arctic until within the last few dozen millenia. Thus I would guess that big-game hunting contributed only modestly to our food intake until after we had evolved fully modern anatomy and behaviour. I doubt the usual view that hunting was the driving force behind our uniquely human brain and societies. For most of our history we were not mighty hunters but skilled chimps, using stone tools to acquire and prepare plant food and small animals. Occasionally, men did bag a large animal, and then retold the story of that rare event incessantly.

In the period just before the Great Leap Forward, at least three distinct human populations occupied different parts of the Old World. These were the last truly primitive humans, supplanted by fully modern people at the time of the Great Leap. Let's consider those among the last primitives whose anatomy is best known and who have become a metaphor for brutish subhumans: the Neanderthals.

Where and when did they live? Their geographic range extended from Western Europe, through southern European Russia and the Near East, to Uzbekhistan in Central Asia near the border of Afghanistan. (The name 'Neanderthal' comes from Germany's Neander Valley (valley = Thai in German), where one of the first skeletons was discovered.) The time of their origin is a matter of definition, since some old skulls have characteristics anticipating later full-blown Neanderthals. The earliest 'full-blown' examples date to around 130,000 years ago, and most specimens postdate 74,000 years ago. While their start is thus arbitrary, their end is abrupt: the last Neanderthals died around 40,000 years ago. During the time that Neanderthals flourished, Europe and Asia were in the grip of the last Ice Age. Neanderthals must have been a cold-adapted peoplebut only within limits. They got no further north than southern Britain, northern Germany, Kiev, and the Caspian Sea. The first penetration of Siberia and the Arctic was left to later, fully modern humans.

Neanderthals' head anatomy was so distinctive that, even if a Neanderthal dressed in a business suit or a designer dress were to walk down the streets of New York or London today, everybody else (all the homines sapientes) on the street would be staring in shock. Imagine converting a modern face to soft clay, gripping the middle of the face from the bridge of the nose to the jaws in a vice, pulling the whole mid-face forward, and letting it harden again. You will then have some idea of a Neanderthal's appearance. Their eyebrows rested on prominently-bulging bony ridges, and their nose and jaws and teeth protruded far forward. Their eyes lay in deep sockets, sunk behind the protruding nose and brow ridges. Their foreheads were low and sloping, unlike our high vertical modern foreheads, and their lower jaws sloped back without a chin. Despite these startlingly primitive features, Neanderthals' brain size was nearly ten per cent greater than ours! A dentist who examined a Neanderthal's teeth would have been in for a further shock. In adult Neanderthals, the incisors (front teeth) were worn down on the outer-facing surface, in a way found in no modern people. Evidently, this peculiar wear-pattern somehow resulted from a use of their teeth as tools, but what exactly was that function? As one possibility, they may have routinely used their teeth as a vice to grip objects, like my baby sons, who gripped their milk bottle in their teeth and ran around with their hands free. Alternatively, Neanderthals may have bitten hides with their teeth to make leather, or bitten wood to make wooden tools. While a Neanderthal in a business suit or dress would attract attention today, one in shorts or a bikini would have drawn gasps. Neanderthals were more heavily muscled, especially in their shoulders and neck, than all but the most avid modern bodybuilders. Their limb-bones, which took the force of those big muscles when they were contracting, had to be considerably thicker than ours to withstand the stress. Their arms and legs would have looked stubby to us, because the lower leg and forearm were relatively shorter than ours. Even their hands were much more powerful than ours; a Neanderthal's handshake would have been literally bone-crushing. While their average height was only around 5 feet 4 inches, their weight would have been at least 20 pounds more than that of a modern person of that height, and this excess was mostly in the form of lean muscle. One other possible anatomical difference is intriguing, though its reality as well as its interpretation are quite uncertain. A Neanderthal woman's birth canal may have been wider than a modern woman's, permitting her baby to grow inside her to a bigger size before birth. If so, a Neanderthal pregnancy might have lasted a year, instead of our nine months. Besides their bones, our other main source of information about Neanderthals is their stone tools. Like the earlier human tools, Neanderthal tools may have been simple hand-held stones not mounted on separate parts such as handles. The tools do not fall into distinct types with unique functions. There were no standardized bone tools, no bows and arrows. Some of the stone tools were undoubtedly used to make wooden tools, which rarely survive. One notable exception is a wooden thrusting spear 8 feet long, found in the ribs of a long-extinct species of elephant at an archaeological site in Germany. Despite that (lucky?) success, Neanderthals were probably not very good at big-game hunting, because Neanderthal numbers (to judge from the number of their sites) were much lower than those of later Cro-Magnons, and because (as I will explain later) even anatomically more modern people living in Africa at the same time as the Neanderthals were undistinguished as hunters.

If you say 'Neanderthal' to friends and ask for their first association, you will probably get back the answer 'caveman'. While most excavated Neanderthal remains do come from caves, that is surely an artifact of preservation-, since open-air sites would be eroded much more quickly. Among my hundreds of campsites in New Guinea, one was in a cave, and that is the only site where future archaeologists are likely to find my pile of discarded tin cans intact. So archaeologists will also be deceived into considering me a caveman. Neanderthals must have constructed some type of shelter against the cold climate in which they lived, but those shelters must have been crude. All that remains are a few piles of stones and a pesthole, compared to the elaborate remains of houses built by the later Cro-Magnons.

The list of other quintessentially modern human things that Neanderthals lacked is a long one. They left no unequivocal art objects. They must have worn some clothing in their cold environment, but it had to be crude, as they lacked needles and other evidence of sewing. They evidently lacked boats, as no Neanderthal remains are known from Mediterranean islands nor even from North Africa, just eight miles across the Straits of Gibraltar from Neanderthal-populated Spain. There was no longdistance overland trade: Neanderthal tools are made of stones available within a few miles of the site.

Today we take cultural differences among people inhabiting different areas for granted. Every human population alive today has its characteristic house-style, implements, and art. If you were shown chopsticks, a Guinness beer bottle, and a blowgun and asked to associate one object each with China, Ireland, and Borneo, you would have no trouble giving the right answers. No such cultural variation is apparent for Neanderthals, whose tools look much the same whether they come from France or Russia.

We also take cultural progress with time for granted. The wares from a Roman villa, medieval castle, and 1990 New York apartment differ obviously. In the year 2000 my sons will look with astonishment at the slide rule I used for calculations throughout the 1950s: 'Daddy, are you really that old? But Neanderthal tools from 100,000 and 40,000 years ago look essentially the same. In short, Neanderthal tools had no variation in either time or space to suggest that most human of characteristics, innovation. As one archaeologist put it, Neanderthals had 'beautiful tools stupidly made'. Despite Neanderthals' big brains, something was still missing. Grandparenting, and what we consider old age, must also have been rare among Neanderthals. Their skeletons make clear that adults might live to their thirties or early forties, but not beyond forty-five. If we lacked writing and if none of us lived past forty-five, just think how the ability of our society to accumulate and transmit information would suffer. I have had to mention all these subhuman qualities of Neanderthals, but there are three respects in which we can relate to their humanity. First, virtually all well-preserved Neanderthal caves have small areas of ash and charcoal indicating a simple fireplace. Hence, although Peking Man may have already used fire hundreds of thousands of years earlier, Neanderthals were the first people to leave undisputed evidence of the regular use of fire. Neanderthals may also have been the first people who regularly buried their dead, but that is disputed, and whether it would imply religion is a matter of pure speculation. Finally, they regularly took care of their sick and aged. Most skeletons of older Neanderthals show signs of severe impairment, such as withered arms, healed but incapacitating broken bones, tooth loss, and severe osteoarthritis. Only care by young Neanderthals could have enabled such older Neanderthals to stay alive to the point of such incapacitation. After my long litany of what Neanderthals lacked, we have finally found something that lets us feel a spark of kindred spirit in these strange creatures of the last Ice Agenearly human in form, and yet not really human in spirit.

Did Neanderthals belong to the same species as we do? That depends on whether we could and would have mated and reared a child with a Neanderthal man or woman, given the opportunity.

Science-fiction novels love to imagine the scenario. You may remember the blurb on many a back cover:

A team of explorers stumbles on a steep-walled valley in the centre of deepest Africa, a valley that time forgot. Here they find a tribe of incredibly primitive people, living in ways that our stone-age ancestors discarded thousands of years ago. Do they belong to the same species as we do? There's only one way to find out, but who among the intrepid explorers can bring himself [male explorers, of course] to make the test?

At this point one of the bone-chewing cavewomen suddenly is described as beautiful and sexy in a primitively erotic way, so that modern novel readers will find the brave explorer's dilemma believable: does he or doesn't he have sex with her?

Believe it or not, something like that experiment actually took place. As we shall now see, it happened repeatedly around 40,000 years ago, at the time of the Great Leap Forward.

I mentioned that the Neanderthals of Europe and Western Asia were just one of at least three human populations occupying different parts of the Old World around 100,000 years ago. A few fossils from Eastern Asia suffice to show that people there differed from Neanderthals as well as from us moderns, but too few bones have been found to describe these Asians in more detail. The best characterized contemporaries of the Neanderthals are those from Africa, some of whom were virtually modern in their skull anatomy. Does this mean that, 100,000 years ago in Africa, we have at last arrived at the watershed of human cultural development?

Surprisingly, the answer is still 'no'. The stone tools of these modern-looking Africans were very similar to those of the decidedly unmodern-looking Neanderthals, hence we refer to them as

'Middle Stone Age Africans'. They still lacked standardized bone tools, bows and arrows, nets, fishhooks, art, and cultural variation in tools from place to place.

Despite their almost modern bodies, these Africans were still missing that vital something necessary to endow them with full humanity. Once again, we face the paradox that almost modern bones, and presumably almost modern genes, are not enough by themselves to produce modern behaviour.

Some South African caves occupied around 100,000 years ago provide usfor the first time in human evolutionwith detailed information about what people actually were eating. Our confidence stems from the fact that the African caves are full of stone tools, animal bones with cut-marks from stone tools, and human bones, but few or no bones of carnivores like hyenas. Thus, it is clear that people, not hyenas, brought the bones to the caves. Among the bones are many of seals and penguins, as well as shellfish such as limpets. Hence Middle Stone Age Africans are the first people for whom there is even a hint that they exploited the seashore. However, the caves contain very few remains offish or flying seabirds, undoubtedly because people still lacked the fishhooks and nets needed to catch fish and birds. The mammal bones from the caves include those of quite a few medium-sized species, among which those of eland, an antelope, predominate by far. Eland bones in the caves represent eland of all ages, as if people had somehow managed to capture a whole herd and kill every individual. At first, the relative abundance of eland among hunters' prey is surprising, since the caves' environment 100,000 years ago was much as it is today and since eland is now one of the least common large animals in the area. The secret to the hunters' success with eland probably lay in the fact that eland are rather tame, not dangerous, and easy to drive in herds. This suggests that hunters occasionally managed to drive a whole herd over a cliff, explaining why the distribution of eland age groups among the cave kills is like that in a living herd. In contrast, remains of more dangerous prey such as Cape buffalo, pigs, elephants, and rhinos yield a very different picture. Buffalo bones in the caves are mainly of very young or very old individuals, while pigs, elephants, and rhinos are virtually unrepresented.

Middle Stone Age Africans can be considered big-game hunters, but only barely. They either avoided dangerous species entirely or confined themselves to old, weak animals or babies. Those choices reflect sound prudence on the hunters' part, since their weapons were still spears, for thrusting, rather than bows and arrows. Along with drinking a strychnine cocktail, poking an adult rhinoceros or Cape buffalo with a spear ranks as one of the most effective means of suicide that I know. Nor could the hunters have succeeded often at driving eland herds over a cliff, since elands were not exterminated but continued to coexist with hunters. As with earlier peoples and modern stone-age hunters, I suspect that plants and small game made up most of the diets of these not-so-great Middle Stone Age hunters. They were definitely more effective than chimpanzees, but not up to the skill of modern Bushmen and Pygmies. Thus, the scene that the human world presented from around 100,000 to somewhat before 50,000 years ago was this. Northern Europe, Siberia, Australia, the oceanic islands, and the whole New World were still empty of people. In Europe and Western Asia lived the Neanderthals; in Africa, people increasingly like us moderns in their anatomy; and in Eastern Asia, people unlike either the Neanderthals or Africans but known from only a few bones. All three of these populations were, at least initially, still primitive in their tools, behaviour, and limited innovativeness. The stage was set for the Great Leap Forward. Which among these three contemporary populations would take that leap?

The evidence for an abrupt rise is clearest in France and Spain, in the Late Ice Age around 40,000 years ago. Where there had previously been Neanderthals, anatomically fully modern people (often known as Cro-Magnons, from the French site where their bones were first identified) now appear. Had one of those gentlemen or ladies strolled down the Champs Elysees in modern attire, he or she would not have stood out from the Parisian crowds in any way. As dramatic to archaeologists as the Cro-Magnons' skeletons are their tools, which are far more diverse in form and obvious in function than any in the earlier archaeological record. The tools suggest that modern anatomy had at last been joined by modern innovative behaviour. Many of the tools continued to be of stone, but they were now made from thin blades struck off a larger stone, thereby yielding ten times more cutting edge from a given quantity of raw stone than previously obtainable. Standardized bone and antler tools appeared for the first time. So did unequivocal compound tools of several parts tied or glued together, such as spear points set in shafts or axe-heads fitted on to wooden handles. Tools fall into many distinct categories whose function is often obvious, such as needles, awls, mortars and pestles, fishhooks, net-sinkers, and rope. The rope (used in nets or snares) accounts for the frequent bones of foxes, weasels, and rabbits at Cro-Magnon sites, while the rope, fishhooks, and net-sinkers explain the bones offish and flying birds at contemporary South African sites.

Sophisticated weapons for safely killing dangerous large animals at a distance now appearweapons such as barbed harpoons, darts, spear-throwers, and bows and arrows. South African caves occupied by people now yield bones of such vicious prey as adult Cape buffalo and pigs, while European caves were full of bones of bison, elk, reindeer, horse, and ibex. Even today, hunters armed with high-powered telescopic rifles find it hard to bag some of these species, which must have required highly skilled communal hunting methods based on detailed knowledge of each species' behaviour.

Several types of evidence testify to the effectiveness of Late Ice Age people as big-game hunters. Their sites are much more numerous than those of earlier Neanderthals or Middle Stone Age Africans, implying more success at obtaining food. Numerous species of big animals that had survived many previous ice ages became extinct towards the end of the last Ice Age, suggesting that they were exterminated by human hunters' new skills. These likely victims include the mammoths of North America (Chapter Eighteen), Europe's woolly rhino and giant deer, southern Africa's giant buffalo and giant Cape horse, and Australia's giant kangaroos (Chapter Nineteen). Thus, the most brilliant moment of our rise already contained the seeds of what may yet prove a cause of our fall.

Improved technology now allowed humans to occupy new environments, as well as to multiply in previously occupied areas of Eurasia and Africa. Australia was first reached by humans around 50,000 years ago, implying watercraft capable of crossing stretches of water as much as sixty miles wide between eastern Indonesia and Australia. The occupation of northern Russia and Siberia by at least 20,000 years ago depended on many advances: tailored clothing, whose existence is reflected in eyed needles, cave paintings of parkas, and grave ornaments marking outlines of shirts and trousers; warm furs, indicated by fox and wolf skeletons minus the paws (removed in skinning and found in a separate pile); elaborate houses (marked by pestholes, pavements, and walls of mammoth bones), with elaborate fireplaces; and stone lamps to hold animal fat and light the long Arctic nights. The occupation of Siberia and Alaska in turn led to the occupation of North America and South America around 11,000 years ago (Chapter Eighteen). Whereas Neanderthals obtained their raw materials within a few miles of home, Cro-Magnons and their contemporaries throughout Europe practised long-distance trade, not only for raw materials for tools but also for 'useless' ornaments. Tools of high-quality stone such as obsidian, jasper, and flint are found hundreds of miles from where those stones were quarried. Baltic amber reached southeastern Europe, while Mediterranean shells were carried to inland parts of France, Spain, and the Ukraine. I saw very similar patterns in modern stone-age New Guinea, where cowry shells prized as decorations were traded up to the highlands from the coast, bird-of-paradise plumes were traded back down to the coast, and obsidian for stone axes was traded out from a few highly valued quarries.


TWO THE GREAT LEAP FORWARD | The rise and fall of the third chimpanzee | WORLD CONQUEST