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 us—for the first time in human evolution—with 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 appear—weapons 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.