Out of Eden: The Peopling of the World

by Oppenheimer, Stephen

  Other potential western influences on China and Southeast Asia at the LGM, which may have developed in parallel with the Siberian Upper Palaeolithic, are a flaked stone industry in the Tarim River basin on the southern margins of the Taklamakan Desert of Xinjiang province and a microblade industry on the Qinghai-Tibet Plateau (a microblade is a small prismatic parallel-sided flake struck from a prepared core).40

  Some western Upper Palaeolithic technical influences appeared in northern China and southern Inner Mongolia even before the ice age. Perhaps the earliest, between 35,000 and 50,000 years ago, have been uncovered near a loop of the middle Yellow River known as the Ordos Plateau. The famous Upper Cave near Beijing yielded sophisticated bone, shell, and stone artefacts from around the LGM, including an eyed needle and a complex necklace of bone, shell, and stone dated to around 18,000 years ago. Even more sophisticated Upper Palaeolithic cultures, featuring three-eyed needles and bone-and-antler tools, continued to develop after the LGM along the lower reaches of the Yellow River towards the coast.41 But much of the east coast of China which was most habitable during the LGM now lies under the sea, inaccessible to the archaeologist.

  Farther to the north and east, the Russian Far East, Japan, and Korea showed dramatic changes in technology at the time of the LGM. In the Russian Far East, the earliest carbon-dated Upper Palaeolithic macroblade site is what has become known as the Geographical Society Cave, on the Amur River. (Any blade longer than about 50 mm (2 inches) is classified as a macroblade.) Microblades first appear in this region around the LGM (19,350 years ago) but nearer the coast of the Sea of Japan, in Primorye.42

  Japan has one of the most detailed sequential records of events around the LGM anywhere in the world. Before 20,000 years ago, Japan shared the East Asian predominantly core tool and chopper-chopping tradition. Between 18,000 and 20,000 years ago this gave way to a rich new stone technology, reminiscent of the Western Upper Palaeolithic, with flakes and blades (the latter becoming more and more frequent with time) and a profusion of other derived products. Finally, from 12,000 to 14,000 years ago, microblades and bifacial points became common. Korea remains rather less intensively researched, although the same sequence of core tools giving way to flakes then blades around the time of the LGM has been found. In both of these sequences we see the period around the ice age as a time of expansion and technological change, with old East Asian traditions being swept away, presumably by an influx of skills and hunters coming in from the freezing Asian steppe to the west.43

  The regions around the Yangtzi River in southern China appear to have been shielded to a certain extent from the full impact of Western Upper Palaeolithic technology, but the preglacial, quartzite-based chopper-chopping industry was modified (although not replaced) at the LGM by new tools and materials. The new tools were smaller and more varied, including flakes, and were also fashioned from other materials such as chert, bone, and antler. As in the north, the coastal regions of southern China at the LGM now lie deep beneath the waves, hiding any possible evidence of LGM technical change on the seafront.44

  Southeast Asia: a gap in occupation, or just the effects of sea level?

  In contrast to the clear technological changes that took place around the LGM farther north, Southeast Asia has very little to show from around the climax of the last ice age. In fact, there are few remains of material culture of any description. Whether this dearth of evidence reflects a lack of people or an absence of evidence in the right places, it cannot be used to support the idea of immigration from the north. The masking effect of low sea levels during the LGM is nowhere so great as in Southeast Asia, where the present land above the water is but a meagre remnant of the former continent of Sundaland (see Figure 6.3). David Bulbeck has pointed out that the reason why there is so little evidence of occupation at the time of the LGM may be that people generally lived on land less than 100 metres (330 feet) above sea level. They thus simply followed the sea, moving down from the hinterland as the sea fell to occupy land which is now beneath the waves. When the sea rose again after the LGM they moved back inland, and this is the point where their cultures reappear in the modern archaeological record.45

  Whatever the reason, the result is an apparent gap of occupation in inland Indo-China and the Malay Peninsula from around the LGM until about 14,400 years ago, when inland caves were reoccupied by people making pebble and chopper-chopping tools. In some cases the old lithic traditions continued right through the Neolithic period until 2,000 to 3,000 years ago. Since these regions were clearly habitable during the LGM, it is more likely that their occupiers had simply moved back from lower altitudes as the sea level rose.46

  The interesting question is who these cave-dwelling, pebble-tool-using people were. It is generally thought that they were the ancestors of the nomadic Negrito forest hunter-gatherers who still occupy the same regions today. Archaeologist Zuraina Majid argues further that the post-glacial technology of the Lenggong Valley in Malaysia was really a continuation of traditions that locally go right back to the valley site of Kota Tampan, now tentatively dated to 74,000 years ago (see also Chapter 4). There is some genetic evidence that the ancestors of the Aboriginal Malays could have been living on the Indo-Chinese coastline as well over the same period. Again, the sea would have covered their traces.47

  The picture of changes around the LGM is only slightly more revealing in Island Southeast Asia, where a flake-and-blade technology lasted to within the last 2,000 years. There are clues that there was an expansion into Island Southeast Asia during the ice age, as implied by the first evidence of colonization of the Philippines from 17,000 years ago. American archaeologist Wilhelm Solheim, doyen of Southeast Asian prehistory, sees the flake-and-blade tradition as a late Pleistocene intrusion to Island Southeast Asia from South China rather than as being home-grown.48

  Perhaps the only star find that could signal an intrusion of really smart new technology, as it were from another planet, is in eastern Sabah on the shores of the extinct Lake Tingkayu. Beautifully, bifacially worked lanceolate chert knives have been found here with a date inferred to be between 18,000 and 28,000 years ago. (‘Lanceolate’ means shaped like the head of a lance or leaf.) The latter date would suggest an arrival before rather than after the LGM. In Peter Bellwood’s words, these knives are ‘unique in the whole of Southeast Asia, except for one apparent lanceolate found . . . in a tin mine in Kedah in Peninsular Malaysia.’ If the Tingkayu knives from Borneo really were an introduced style, Bellwood’s comment may be a clue to a route taken by the technology from China, since he also mentions the two other preglacial sites on the same peninsula, but on the Thai side: Moh Khiew and Lang Rongrien. At each site there is some evidence for similar bifacial technology, but overlain by the ‘cruder’ Hoabinhian tools.49

  Bellwood also finds technical echoes of the Tingkayu lanceolate points in Northeast Asia – specifically in the Diuktai of northeastern Siberia (since 18,000 years ago) and several regions of Japan from the same time.50 Although Bellwood feels that the Tingkayu culture is an independent local event, the cultural echoes he describes would be just the same as those suggested by the genetic model I have put forward. In other words, the dispersal of the hunter-gatherers from the Central Asia steppe around the time of the LGM took high-grade grassland hunting technology east and south-east to regions of China and Sundaland with expanding temperate grasslands. Curiously, the other technical link made with the Diuktai technology is with the New World – the subject of the next chapter, and the last leg of our journey with the first people to arrive at the farthest corners of the globe.

  The extraordinary regional specificity of the paternal and maternal gene trees persisting today has made it possible to trace ancient migrations. It shows us that, as they were filling up the Old World, once people got to where they were going they tended to stay put and, at least until the last five hundred years, were mostly able to repel newcomers. What disturbed this conservatism the most was the LGM. In the northern hemisphere, vast
areas of the Old and New Worlds were rendered uninhabitable by ice, glacial lakes, and polar desert. For the formerly highly successful hunter-gatherers of the North Eurasian steppe there were few choices, and these, as usual, were determined by geography and climate. In the peninsula of Europe, locked in by sea, mountain, and desert, the only chance of survival was to be found in refuges in the more southerly temperate zones bordering the Mediterranean and Black Seas. After the LGM, the refugees re-expanded in number and territory, mostly back to where they had come from.

  In Central and North Asia, formerly covered in grassland and roamed by huge herds of large herbivores, the increasing cold and desiccation forced the Upper Palaeolithic hunter-gathers off the high steppe in several directions to warmer and more temperate regions. These would have included the Ukraine to the west, China to the south and east, and Japan, Korea, and north-east Siberia. As always, the great rivers of Asia could have played a role as highways, but this time the traffic was downstream. The archaeological evidence for this migration of Upper Palaeolithic steppe hunting cultures towards the Pacific coast at the LGM, is best seen in Japan, but is echoed elsewhere. In South and Southeast Asia huge areas of continental shelf opened up for colonization as the sea level fell. How much of the population expansion in Sundaland (greater Southeast Asia during the LGM) resulted from local people, and how much from refugees from farther north, is not clear, but the genetic and dental evidence suggests mostly the former. The drop in sea level also opened a new continent, ‘Beringia’, to the north-east. This provided a land-bridge to the Americas, where our story reaches its final chapter.

  7

  THE PEOPLING OF THE AMERICAS

  THAT THE AMERICAN INDIANS came across the Bering Strait from Asia has been a natural solution to an obvious shared ancestry. As Thomas Jefferson noted in 1784, ‘the resemblance between the Indians of America and the Eastern inhabitants of Asia, would induce us to conjecture, that the former are the descendants of the latter, or the latter of the former . . .’. This even-handed but ambiguous idea had already been given direction 200 years earlier by the Jesuit scientist and traveller José de Acosta, who had suggested that the Asians had come to America 2,000 years before the Spanish. There has not, until recently, been any serious rival to this view.1

  With the exception of the colonization of Polynesia, it is likely that the entry into the Americas was the last of the great expansions of humankind into unexplored territory. With the great recent technical advances in the study of prehistory, intense local interest, and the enormous resources of the world’s richest nation, we might well expect the story of the peopling of the Americas to be wrapped up. We might expect to know approximately when the first entry occurred, how many subsequent migrations there were, who they were, and where they came from, and how and when. We might even expect to have a clue about what sort of languages they spoke.

  Discord in academia

  Nothing could be further from reality. Scientists cannot agree about dates of first entry, having offered estimates ranging from 11,500 to 50,000 years ago. They cannot agree on how many migrations there were, some suggesting one, others many. They cannot even agree on how many Native American language families there have been during historic times, let alone how many entered America. Much of the problem lies in the nature of the evidence and with entrenched, polar academic opinions which have made rational agreement impossible. But, as we shall see, American observers of American prehistorians are becoming increasingly bemused by the very free-enterprise approach to influencing scientific decision-making.2

  Formal scientific method should allow for, even insist upon, the uncertainty of theories. Crudely speaking, a theory (or ‘model’) sets out to provide a logical explanation of something not previously understood, in the best way allowed by the observations. We have to accept that some observations may be inaccurate or even misleading, and that more and better observations may allow a new and better theory to be constructed. Observations which call the new theory into question may well turn up, in which case it will give way to another new theory. The hope is that, sooner rather than later, we can get as close as we can to some ideal reality or truth. It is misleading to assume that we can ever get to that absolute truth. Above all, we should always be open to the possibility of being wrong.

  The reality of academe is rarely like this. Bright young academics make their names with a new theory or some work that breaks the mould, and then spend the rest of their professional lives consolidating and defending their position from attack. Their students, their financial sponsors, and, of course, the public expect much more certainty than is available. This all encourages inflexibility. The gap between reality and credibility has always been filled with that thick, all-purpose glue of society – authority. Senior academics in each field have authority invested in their positions and defend both like high priests. When their authority is threatened by outsiders they perceive their positions to be under threat too, and they close ranks, form alliances, and chase off the pretenders. It is irrelevant whether the threat – some new interpretation which runs counter to a cherished, established view – actually gets closer to the Holy Grail of truth, or merely gives another angle on an opaque subject: the big guns still come out.

  When two ‘authorities’ turn on each other, then we have civil war. The academic ground shakes as the great grey elephants thunder and charge. Neutral and objective colleagues are coerced to take sides, and juniors are advised to beware. Obviously there is a reverse side to such anti-establishment views of academe. Society abounds with adventurers who like to make capital from the unwary masses by exploiting their fascination with mystery. Some writers make large amounts of money, to the disgust of the archaeological establishment, questioning what they choose to label ‘dogma’, for instance whether humans invented their own ancient cultures, rather than the more exciting possibilities of Martian influence. Who could argue that accredited experts should not be there to defend our weak and ignorant minds from such charlatans? The problem of course is for the observer to know who is defending what in each situation.

  The Clovis-first orthodoxy

  What has all this to do with the peopling of the Americas? The answer is, much. The most contentious issue in American archaeology is the so-called Clovis orthodoxy or Clovis-first theory. The history of this orthodoxy goes back perhaps to the end of the nineteenth century, before which time it was a heresy. In the 1890s, William Henry Holmes of the Smithsonian Institution’s Bureau of American Ethnology and Thomas Chamberlin of the United States Geological Survey chased off many dubious claims for Pleistocene (ice-age) occupation of the New World. The mantle of authority for this gatekeeper role was passed in the 1920s to the physical anthropologist Ales Hrdlicka, also of the Smithsonian. Long after, in 1995, Hrdlicka was singled out by American author Vine Deloria in his book Red Earth, White Lies as a heavy-handed zealous defender of the academic status quo who quashed research proposals designed to explore alternative theories.3

  In 1926, Jesse Higgins of the Colorado Museum of Natural History found a pointed stone artefact at a site near Folsom, New Mexico, which also yielded the skeleton of an extinct bison. Hrdlicka refused to accept this as evidence of Pleistocene human occupation since no archaeologist had checked the association with the bones before the point was removed. Another stone point was found in 1927. It was left on site, examined, photographed, and verified by outside experts. Higgins found more and larger points, with the same fluting (fluting is where flakes have been struck from the base, presumably to facilitate hafting), first in 1932 in Colorado, in association with mammoth skeletons, then five years later, again with mammoth bones at Clovis, New Mexico. These larger points, now known as Clovis points, lay beneath representatives of the other type, now known as Folsom points, which were associated with bison skeletons.4

  Thus was it ‘proved’, by the criteria of the time, that humans had entered the New World before 10,000 years ago. The old theory, of a more recent colonizatio
n, was overturned, and ‘the rest is history’ as far as many American archaeologists are concerned. But all was not quite as it should be in a nicely rounded drama. In the cycle of theories, this was the ‘good guy’ phase: authoritative dogma overturned by careful observation and persistence after frustration and denigration. In due course, the wheel would turn.

  Subsequently, Clovis points were turned up throughout the continental United States. The conviction grew among American archaeologists that these stone tools were the signature of the first human colonization of the Americas. After all, surely these first explorers were expert Upper Palaeolithic big-game hunters who had followed the mammoth trail across Beringia from Asia in the waning years of the last glaciation?

  In 1964, American geochronologist C. Vance Haynes collected and linked together the dates of various Clovis-point sites using the new technology of carbon dating. These dates bracketed the earliest Clovis points to 11,000–11,500 years ago, and none was more than 12,000 years old. This latter age was significant for geologists, since they believed this was after the time when a corridor opened up between the two great melting ice sheets of North America and allowed passage from Alaska through Canada to the rest of the Americas (about 12,000–13,000 years ago). These two ice sheets, the Laurentide lying over Hudson Bay to the east and the Cordilleran covering the Rockies to the west, were so large that, on the evidence available in the 1960s, they seemed to span the continent.5 (Figure 7.1.)

  The Clovis-first theory had now matured into a complete and established orthodoxy. The argument went that humans could not have come into America before the Clovis points made their appearance because the way through was blocked by ice. All the Clovis dates pointed to a beginning that coincided with the opening of a vast corridor through the ice running from north-west to south-east from 13,000 years ago. Before this corridor opened, went the argument, no-one could have traversed the ice-sheets. Never mind that, even when it was open, the ice corridor was several thousand kilometres of barren Arctic desert and a lake requiring many packed lunches to traverse – this was the grand theory into which all elements could be fitted. The architects of the theory now became its high priests, and the theory was ripe for the next phase in the cycle of attack and defence of the new status quo. That attack and the fierce defence have now lasted over thirty years.