Out of Eden: The Peopling of the World

by Oppenheimer, Stephen

  The first thing to note, when thinking of possibilities for technology exchange, was that although Neanderthals and moderns coexisted in Europe for between 5,000 and 12,000 years (at some time between 28,000 and 40,000 years ago), all the evidence shows that for most of that time their territories hardly overlapped at all. As the moderns expanded rapidly from Eastern Europe, the Neanderthals, who were concentrated in the west, gradually retreated to their last strongholds – in Italy, then southern France, and finally Spain and Portugal. Careful computer analysis of sites and dates has recently shown that the areas of coexistence were limited to after 35,000 years ago, and to just the two last strongholds, in southern France and in the south-west tip of Spain (Figure 2.2). By that time it was perhaps too little, too late. The reasons for the Neanderthals’ retreat can still only be guessed at. Was it because of violent conflict, for instance, or more peaceful competition? The lack of territorial overlap for 10,000 years suggests a prolonged and probably unfriendly stalemate. However, more overlap might not have helped Neanderthals to change their tool-making methods. The new advances in technology were, after all, something that had taken moderns tens of thousands of years to develop. In the same way that Yali’s people could never get at the secrets of the Europeans’ luxury goods, the Neanderthals could never fully realize the potential of the newcomers’ revolutionary culture if they were not socially close to them. Maybe Neanderthals rarely got the opportunity to pick up the new technology. In spite of these problems, they actually picked up quite a few ‘modern’ habits, mainly during the periods and in the regions of overlap.11

  Hearths and burials

  Built hearths are claimed to be hallmarks of fully modern Upper Palaeolithic behaviour, but hearths as old as 50,000 years have been identified in Russia and Portugal, associated with Mousterian tools, suggesting that the practice was already present in the Middle Palaeolithic and was therefore being used even by Neanderthals. Perhaps one of the most controversial vindications of Neanderthal cultural potential concerns formal burials. Deliberate burial, especially with goods and tools which had been used during life, evocatively suggests at least a concern with what happens after death and perhaps a belief in an afterlife. Such a belief could even be regarded as the first evidence for a particular aspect of religious thought. This kind of philosophical speculation makes it important to identify whether a particular set of bones was deliberately buried and whether or not grave goods are really present.12

  Figure 2.2 Space-time estimates of Neanderthal–modern coexistence. The Neanderthals’ last refuges were in south-west France and Portugal.11

  Complete skeletons can indicate formal burial, but not always. The presence of complete human skeletons dating to times after 100,000 years ago, and particularly for Neanderthals between 40,000 and 60,000 years ago, could alternatively be the result of change in occupation of caves by hyenas and other carnivores. The degree to which grave goods such as flowers, stone circles, goats’ horns, and artefacts were ritually or religiously placed has also been disputed.13 Perhaps the most important evidence that this was just a locally shared cultural innovation is that early burials happened only among humans in West Eurasia, including the early moderns at Qafzeh in Israel (see Chapter 1). There is no evidence for the practice of burial among their contemporaries in Africa. In other words, burial, like many other aspects of Upper Palaeolithic technology, was a local invention in West Eurasia which spread to Neanderthals, who in turn preceded Modern Africans in burying their dead. This sequence undermines the biological determinism that ascribes particular cultural practices exclusively and progressively to particular human species.

  Why talk up Neanderthals at all?

  My reason for taking this apologist stance, fair-brokering the skills of Neanderthals with those of early humans, is not to try to prove they had exactly the same ‘genetically determined’ intellectual potential. There is no way one can claim this on current evidence. Neanderthals, as well as being large-brained, were anatomically different from moderns in other ways, so it would not be a surprise if there were some slight mental differences. No, my purpose is to suggest that the arguments that Neanderthals were culturally backward because they were duller, dumber, or more stupid than the invading moderns are based on a false belief that biological and cultural traits go very closely together. At the very least, as far as Europe is concerned this argument may have been overstated and may have gone further than is justified by the evidence.

  The European Upper Palaeolithic has been glorified as the ‘human revolution’, with dramatic cognitive advances such as abstract thought and speech. Often explicit in this scenario is the concept of a biological advance: the idea that a genetically determined change – a thought or speech gene – somehow brought about the Upper Palaeolithic revolution in Europe. Many of the most dramatic innovations of the modern newcomers were, however, just that: new inventions that had a clear regional and chronological beginning long after our species’ emergence. These late inventions gave the moderns a special local advantage. Neanderthals were outgunned and wrong-footed by the complex culture the newcomers had quite recently developed. By analogy, no anthropologist would dare say that Yali’s Neolithic people in New Guinea had less biological potential than Jared Diamond’s own metal-age people, but it is clear that, as a result of cultural isolation, they had not benefited from certain Western technical innovations of the past 2,000 years, such as guns and steel.

  Why do I defend Neanderthals? The answer is that bad-mouthing Neanderthals, regarding them as people who were like but unlike us, is symptomatic of a deep need among all human societies to exclude and even demonize other groups (see also Chapter 5). I suggest that the unproven dumbing of the Neanderthals is an example of the same cultural preconception that has, by a mistaken geographical logic, cast our own Anatomically Modern African ancestors in the same role, as ‘moderns manqués’. The very real problem for this Eurocentric standpoint is that today’s modern Africans are the direct descendants of those pre-Upper Palaeolithic peoples, and share with them more of their original genes than do any other people in the world. By denigrating their ancestors, by implication we denigrate them.

  The European Upper Palaeolithic: cultural or biological revolution? Clive Gamble is a world expert on the reconstruction of Palaeolithic human behaviour. In a very readable book, Timewalkers, he summarized conventional views and identified the period from 40,000 to 60,000 years ago as the crucial behavioural threshold between ancients and moderns. He describes the end of this timespan, 40,000 years ago, as the time after which the great acceleration took place, with the advent in Europe of art, bone tools, body ornament, open-site burials, storage pits, quarries, exchange of goods, and long-term occupation of harsh environments. He takes the threshold argument further, saying, ‘There is no doubt that after 35,000 BP [before the present] Upper Palaeolithic industries sweep the board, not only in Europe but across much of the Old World, with Australia forming a notable exception . . .’14 This Australian ‘exception’ clearly does not apply to rock art, since six pages later he mentions ‘the rock engravings from Karolta in South Australia, now directly dated to as much as 32,000 BP’. Such a date makes them almost as old as the Chauvet Cave art, and in fact does seem to extend his earlier point, at least partially, to include Australia.

  Others, such as Chicago palaeoanthropologist Richard Klein, take this cultural explosion a stage further and interpret it as a human biological epiphany. In a standard text, The Human Career, written in 1989, he states:

  it can be argued that the Upper Paleolithic signals the most fundamental change in human behavior that the archeological record may ever reveal . . . The strong correlation between Upper Paleolithic artifacts and modern human remains further suggests that it was the modern human physical type that made the Upper Paleolithic (and all subsequent cultural developments) possible. The question then arises whether there is a detectable link between the evolution of modern people and the development of those behavioral t
raits that mark the Upper Paleolithic.

  He then draws attention to the mainly Middle Palaeolithic tools of earlier modern humans, concluding:

  In sum, anatomical and behavioral modernity may have appeared simultaneously in Europe, but in both the Near East and Africa, anatomical modernity antedates behavioral modernity, at least as it is detectable in the archeological record. This observation is difficult to explain. Perhaps . . . the earliest anatomically modern humans of Africa and the Near East were not as modern as their skeletons suggest. Neurologically, they may have lacked the fully modern capacity for culture. This may have appeared only as recently as 40,000 to 50,000 years ago when it allowed [what were by] then fully modern humans to spread rapidly throughout the world.15

  In these explicit biological statements we have one dominant conventional out-of-Africa model that places the chronological and genetic threshold to our modernity (behavioural and neurological) at no more than 50,000 years ago, in West Eurasia and after the out-of-Africa dispersal. This model was conceived before 1989, at a time when it was believed that Australia was colonized only 40,000 years ago. In other words, Klein could interpret the evidence to allow for Australia – and hence also Asia – to have been colonized by Anatomically Modern Humans only after the start of the European Upper Palaeolithic. This made it possible for him to argue that these new ‘neurally enhanced’ moderns in Europe could have then moved on to colonize the rest of the non-African world. Klein published a second edition of his book in 1999, by which time he acknowledged, on the last couple of pages, the problem of possible earlier Australian (and Asian) colonization by 60,000 years ago, and the possibility of harpoon fishing in Africa between 90,000 and 155,000 years ago. In his conclusions he still, however, returns to the argument of a neurological evolutionary (i.e. genetically driven) revolution in Europe 40,000–60,000 years ago: ‘to me it suggests that the fully modern capacity for culture may have appeared only about this time [50,000 years ago]’.16

  Even before we consider the evidence, we can see that this argument implies a biologically deterministic approach to cultural evolution. It assumes that each cultural advance is determined or ‘allowed’ by a genetic change. As I mentioned in the Prologue, human (or other primate) culture is first invented, then learnt and added to from generation to generation. Each advance or skill does not come out of a new gene. Rather, new behaviours come first and the genetic modifications that best exploit those new behaviours come afterwards. In other words, the change of culture precedes the change of body – not the other way round. Furthermore, there are predictable geographical differences of culture. If a particular invention in one region led to other local inventions, the accelerated pace of innovation would give that region a head start. So regional differences in the rate of cultural progression should be expected, even within one human species.

  Did a European wisdom gene spread to everyone else?

  There are several inescapable logical assumptions in Klein’s argument that fully ‘neurally modern’ humans appeared only after 40,000–50,000 years ago. First there is the explicit implication that early African moderns were biologically less than modern – in other words, they did not have the neurological capacity to develop modern behaviours. This strange conclusion would inevitably apply to those moderns left in Africa, and also to the first moderns migrating into Asia and on to Australia, since it is now generally accepted that these colonizations took place quite some time before 50,000 years ago (the earliest possible time for which the Upper Palaeolithic can be identified in the Eastern Mediterranean). What do these hypothetical conclusions mean? They would mean first that the direct ancestors of today’s Africans living between 50,000 and 130,000 years ago were biologically incapable of developing or using Upper Palaeolithic behaviour and technology. They would not be able to paint, carve, trade, organize, and so forth. Many say that they could not speak – or, if they could, that their speech was ‘primitive’. With such disadvantages, presumably they could not, given the opportunity, drive cars or fly planes; compose and play soul, spirituals, reggae, classical music, and jazz; or become doctors, financiers, and geneticists. The mitochondrial DNA and Y-chromosome trees imply that today’s Africans are descended mainly from lines present before 50,000 years ago and not from lines outside Africa. So, why can today’s African descendants do all these things their ancestors were supposedly genetically incapable of?

  There is a further logical problem. If Europeans were the first biologically modern humans and were isolated comparative latecomers, what about the rest of the world? How did they catch up? All living modern humans are fully ‘Anatomically Modern’, and we can trace back our genetic trail to a small ancestral group that started branching in Africa around 190,000 years ago. At no point after that did the total modern population number less than a thousand,17 so we have to imagine that one group inevitably led, by expansion and branching, to many groups.

  The first nucleus of moderns thus expanded, split, and spread early, some branches never to meet again until recent times. This effect of ‘no-return’ separation was never so final as when the one and only successful out-of-Africa group crossed the Red Sea and headed for India and Australia. If, as many evolutionists believe, there was some late genetic change in Europe that made us behaviourally modern as opposed to behaviourally ‘archaic’, this mutation (or mutations) must have occurred at a particular time in individual Europeans after 45,000 years ago – and, obviously, outside Africa.

  A new mutation would have been passed on to all descendant populations that received the mutated gene, but would not have been shared by ‘cousins’ and their descendants. The only exception to this would be if the mutated gene was subsequently shared as a result of cross-marriage. The chance of such cross-marriage would diminish sharply as groups separated and spread around the world. So if there really was, say, a ‘painting mutation’ or a ‘speech mutation’, only those descended from the individual who developed that mutation should inherit the skill. So, if the ‘behaviourally fully modern’ cluster of mutations initially evolved locally in Europeans 40,000–50,000 years ago, then the rest of the colonized world – the Asians, Africans, and Australians – would not be able to paint, carve, speak, make blades, or place a bet on a horse. Nor would their modern descendants. This is clearly absurd, for they can do all those things.

  By this argument, the only way that the original modern colonies of Asians, Africans, and Australians could come up to speed with a European Upper Palaeolithic culture that resulted from a genetic mutation would be if they received infusions of all those new ‘culture genes’. The only biological way of infusing genes, or gene flow, is by migration and intermarriage. But it would not be enough just to have a few foreign cousins. To change all the descendants’ capabilities, the old hypothetical ‘cultural genes’ would have to be completely replaced by the ‘new’. Curiously, this massive gene flow is just the same argument that the discredited multiregionalists use to explain how modern human populations evolved separately in different parts of the world from local Homo erectus variants, yet ended up looking more like one another than the local erectus types. The main problem with the gene-flow levelling theory is that the geography of the mtDNA and Y-chromosome trees shows no evidence of such large-scale inter-regional mixing

  Let’s take a cultural example. For Australians to have been producing rock art 32,000 years ago (which, apparently, they did), at the same time as it first appeared in Europe, would have required an instantaneous and massive gene flow round the globe from Europe to biologically ‘enable’ them to get to that level. It is a ludicrous idea, which can easily be tested. We can see from the genetic record that although modern Australians share with Europeans the two out-of-Africa M and N ancestors from over 80,000 years ago, they preserve their own M and N types. There is no evidence that they are descended from Europeans. Nor was there any significant gene flow from Europe to Australia during the rest of the Palaeolithic.18

  Lack of genetic mixing
after out-of-Africa is the general rule

  The genetic evidence from the male-line and female-line markers, the Y chromosome and mtDNA, in fact shows the opposite of massive gene flow. One of the most important messages of the Y-chromosome and mtDNA stories is that, after the initial modern human dispersals out of Africa, each Old World and Antipodean region became settled, and little if any further inter-regional gene flow happened until the build-up to the last great glaciation 20,000 years ago. Both genetic marker systems show clear regional and intercontinental divisions.

  Cultural diffusion (a sort of seepage or spread of culture not requiring much people movement) during the Palaeolithic is a more likely method of long-distance cultural transmission and one which does not necessarily require gene flow. However, could it really have been possible for 32,000-year-old Australian rock art to be derived from that of Europe at the same time? The culture would have to have been passed halfway around the world in an impossibly short space of time.

  The simplest answer, which does away with this paradox and similar ones, is that the African ancestors of all non-Africans came out of Africa painting, talking, singing, and dancing – and fully modern! There is thus much biological as well as logical evidence against a genetic evolutionary event leading on to fully modern humans 40,000 years ago in the Levant, Europe, or anywhere else outside Africa. This leads us on to examine the direct archaeological evidence and anthropological arguments for the simpler model, namely that the first Anatomically Modern Africans were already fully modern in their intellectual potential.