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Back before we had adequate fossil evidence, the answer seemed to be yes. Many scientists saw these Goliaths as our sensual alter-egos, doomed to fail in the face of intellect and compassion. Increasingly, however, finds began to indicate that Neanderthals were more like us than we once thought. Though their tools were in some cases less sophisticated than those of the Cro-Magnons, the contemporaries of Neanderthals that went on to become modern humans, their craftsmanship represents foresight and ingenuity that has never been displayed in any nonhuman species of animal. They used fire, wore clothing, and probably had a spoken language. Most significantly, they valued human life. Not only did they bury their dead, but some Neanderthals lived for years with injuries that would have killed them sooner if they hadnāt received help from others. How human, then, were they? Some look into the Neanderthal face and see something more familiar than alien. For them, the sloping forehead and protruding brow represent simple ethnic variation. The sunken eyes hold the wisdom of an unexplored human culture. To others, Neanderthals were our ancestral black sheep, victims of their own evolutionary shortcomings. To air out the issues of this debate (which extends to the spelling of Neandert[h]al), we invited four experts to discuss Neanderthal identity. Who were Neanderthals in comparison to modern humans, and why did they disappear 35,000 years ago while their Cro-Magnon neighbors were able to survive? Each scientist proves that there is more than one way to read the evidence. Dr. Erik Trinkaus Washington University, St. Louis Thereās no question that Neanderthals, like all late Pleistocene humans, were related to modern humans. As humans started spreading across the Old World some 1.5 million years ago, they became regionally differentiated. Part of that is a result of different environmental factors acting on them and part is what geneticists call isolation by distance: Groups within a species separated by distance will develop genetic variations for purely random reasons. The Neanderthals are the western Eurasian group of this dispersal and differentiation. At that time, there were also humans living in Asia, towards Australia, in Indonesia, as well as in Africa. You can call each group a separate species, you can call each of them a subspecies. Itās irrelevant. The point is, Neanderthals are just one regional group of late-archaic humans that were evolving in their own way in their own part of the world.
But though we know the basic intellectual capabilities of Neanderthals should have been essentially the same as our own, we also know from their artifacts that they had not elaborated their cultural system to the extent that Cro-Magnons had. And so many aspects that we associate with intelligence were probably underdeveloped among the Neanderthals. The reason for this lies in cultural evolution. Technological development is cumulative over long periods of time; after all, they didnāt have computers 5,000 years ago. As we go back in time, cultural systems as a whole become simpler and simpler, and the Neanderthal cultural system happened to be simple. We can also deduce from the fossils that, to make up for their underdeveloped cultural systems, which were not sufficiently advanced for them to stay warm or get food on a daily basis, Neanderthals adapted physically. They obviously had to maintain their extremely strong builds, otherwise they would have eventually lost muscle tone and mass. Lesions on Neanderthal arm bones and skulls also indicate that, like rodeo riders, Neanderthals had a lot of contact with large animals and needed strength regularly. But despite Neanderthal adaptations, their biology was replaced by that of modern humans. Itās possible some Neanderthal groups contributed to some modern human populations and eventually became genetically absorbed in central and eastern Europe. Weāre talking humans across the landscape who occasionally came into contact with other human beings. Theyāre going to exchange mates. But it was geographically variable. In areas such as western Europe, they may have gone extinct without issue. We have little evidence that they died out because of competition. Most of these groups were fairly thin across the landscape. They would have been competing much more with other animals than with each other. Their slow technology may have been a disadvantage to them, but their other adaptations allowed them to survive for over 100,000 years. So itās difficult to say why they disappeared. [For the record, Dr. Trinkaus prefers Neandertal spelled without the h.] Dr. Michael Walker Murcia University, Spain I think that there are two ways of looking at the issue of our relationship to the Neanderthals, and I have a foot in both camps. People trained primarily in biology tend to dehumanize Neanderthals. They emphasize the differences between us and them, and they use a Darwinist view of speciation to say that, basically, Neanderthals were a different species because they acted and looked differently from us. As a biologist, I can understand that. On the other hand, I also share the archaeologistās viewpoint, which emphasizes the many similarities between us and Neanderthals. I have some sympathy with those who argue from their fossils that Neanderthals behaved differently and had different selective pressures than Cro-Magnons. But as an archaeologist, I think thereās a major problem that has to be addressed: Middle Palaeolithic ÷or Mousterian÷toolkits are by no means specific. Most prehistorians once thought that Neanderthals developed stone-flake tools. We now know that proto-modern humans used stone-flake tools 120,000 years ago in Israel, much as did European Neanderthals 40,000 years ago. Put bluntly, if we find particular kinds of stone tools, weāre unsure just what kind of forerunner made them unless we find its skeleton with them. I think one only has to look at the toolkits from about 100,000 years ago at sites like Skhul and Qafzeh in Israel to see that Cro-Magnon toolkits were essentially the same as those of Neanderthals. What this indicates to me is that Neanderthals and Cro-Magnons behaviorally were quite similar. Of course, this makes it rather hard for me to accept that Neanderthal anatomical and morphological features are somehow related to a behavioral pattern that differed from that of all ancestral forms of Homo sapiens in the second half of the middle Pleistocene, from about 300,000 to 100,000 years ago. If their behavior and selective pressures were so different, why were their toolkits essentially the same? And if behavior dictates body shape, then Cro-Magnons÷given their smaller brains÷should have been sturdier by far than the larger-brained Neanderthals. But they werenāt. Such issues make me a little suspicious of arguments that like to put Neanderthals in a separate species level from us based solely on morphology. We donāt see gorillas and chimpanzees using the same tools.
The problem is, of course, that Neanderthals died out while Cro-Magnons went on to become modern humans. Is this divergence so great that there was no genetic continuity? Iām inclined to think that there was some interbreeding. This takes us back to the main point at issue, which is that those more biological anthropologists who believe in Darwinism as a matter of faith think that anything that isnāt precisely modern had to be a different species and therefore non-human by definition. Many of us, on the other hand, think the evidence points to a gradual, cumulative change from animal to human. But then we have a problem, which is how to explain the Neanderthal -modern divergence 35,000 years ago. So weāre not off the hook either! n For more information, see www.um.es/antropofisica or contact Michael Walker at mwalker@um.es. The Natural History Museum, London Neanderthals were certainly advanced humans. They walked upright and had large brains like modern humans. But I actually regard them as being a different species: Homo neanderthalensis. If we define Homo sapiens by what we find in people today, we can include Cro-Magnons quite easily. We also share many characteristics with Neanderthals, but they developed specializations that took them off the line of evolution that was leading to us. If you have a Neanderthal skull in front of you and know what youāre looking for, you could never, ever confuse it with a modern skull. Neanderthals show us that there is more than one way to be human.
What this may indicate is that there was a mental difference between Neanderthals and Cro-Magnons. Of course, weāre on tricky ground here because we havenāt got preserved brains, and even if we had them, we couldnāt really judge the quality. But I think that by the time we get to the last 40,000 years, modern humans seem to be technologically superior to Neanderthals. When we go back to 100,000 years ago and beyond, there is much less evidence of a distinction. The stone tools are fundamentally similar. But I see a widening gap. By the time we get to 40,000 years ago, itās quite a wide gap, and I think itās partly based in the brain. Neanderthal brains were as big and in some cases bigger than those of modern humans, but modern humans may have had some superiorities in areas such as planning. And language may be part of the story, too. Though Neanderthals likely talked to each other, perhaps they didnāt have the kind of language complexity that enables sophisticated ideas, such as the detailed notions of past, present, and future. What Neanderthals did they did well, but they were limited. These limitations may have put Neanderthals at a disadvantage, causing them to eventually fade away. Some argue that they interbred with Cro-Magnons, gradually becoming genetically absorbed. I think that the two groups were similar enough so that they probably could have interbred, but I donāt see evidence in the fossil record that this was normal behavior. I think that more likely, Neanderthals were outcompeted by the Cro-Magnons. Neanderthals survived in ice-age Europe a long time, but then, for the first time, they had to face a competing species that was more adaptable than they were. I donāt think it was a big superiority; if it was big, the transition would have been rapid. But the fact is, it took at least 10,000 years for the Cro-Magnons to take over. They probably had only slightly better rates of reproductive success, but enough so that they eventually survived at the expense of the Neanderthals. One of the central questions regarding Neanderthal behavior and their ability to compete with other prehistoric foragers is whether they had the ability to use language. Terry Deacon, a Boston University anthropologist, demonstrated that a brain with 1,000 cubic centimeters is large enough to be aligned like the modern human brain. With 1,300 to 1,600 cc brains on average, Neanderthals must have had the mental capability to speak. A Neanderthal hyoid bone discovered in Kebara cave, Mt. Carmel, Israel, indicates that Neanderthals also had the physical capability to speak. Although some archaeologists have argued that symbolic behavior, such as making art objects or body decorations, is the only proof for the use of modern language, we donāt always find this to be the case. Cro-Magnons in western Europe produced art during the Upper Palaeolithic, but Upper Palaeolithic Cro-Magnons in the Near East and southern Africa produced hardly any art at all. The absence or presence of art in Neanderthal sites, therefore, does not indicate whether Neanderthals spoke or thought like Cro-Magnons.
Similarly, technological differences between Neanderthal and Cro-Magnon sites should not be attributed to intellectual differences between the two groups. Take the speed of communication. Horse-drawn carts were invented around 2,000 b.c. So, between 40,000 and 4,000 years ago, the rate of communication stayed the same. From 4,000 years ago to the invention of the train about 200 years ago, the speed of communication was the same. Now, do you think that Newton, Aristotle, or Moses was less intelligent than we are? Technological progress has nothing to do with intelligence. It has something to do with social structure and the economy.
Instead of assuming Cro-Magnons had physical and mental advantages over Neanderthals, why donāt we see the Cro-Magnons as an invading population? Archaeological finds indicate that Neolithic farmers moved into Europe, eventually driving Mesolithic hunter-gatherers to extinction. We have plenty of examples for such events throughout history. Perhaps Cro-Magnons did not treat Neanderthals any better than some of the Europeans treated the Native Americans.
In sum, I donāt see the Neanderthals as being less capable than the Cro-Magnons. They simply lost their land in the conflict with the incoming Cro-Magnon groups. On the other hand, one should ask what special capacities Cro-Magnons possessed that made them successful. I feel that the answer lies in their methods or means of communication, their technical abilities to secure the survival of newborns and the elders in the group, and probably their hunting techniques. The Neanderthals were the losers because the incoming Cro-Magnons were technically and socially better equipped. |
To better understand where evolution led in Neanderthals, we look for clues in their anatomy. We can use fossil evidence to better understand, among other things, Neanderthal intelligence. This is difficult to do, of course, because we donāt even know what intelligence is in the modern world. But what we can talk about is whether their basic neurological capabilities÷symbolism and complex processing÷are similar to our own. By looking at the fossils, we see that their genetically determined mental ability must have been similar, if not identical, to that of early modern humans. The reason for that is, first of all, their brain-size to body-size scale is the same as in modern humans. The second reason is that we know brains are energetically quite expensive. It is selectively very disadvantageous to have a large brain unless youāre using it. The third point is that the basic wiring of the human brain resembles that of non-human primates, like apes or chimps. The biggest difference is that the human brain demonstrates a tremendous elaboration of systems that are already present in the chimp brain. The point is, if any human is going to develop a brain as large as the Neanderthals had, it is very unlikely that he or she would evolve something very different from what modern humans have.
To better understand our relationship to Neanderthals, I think that we have to go right back to the beginning, back into the Pliocene 4 or 5 million years ago. From the moment our first forebears split off from the common ancestor with the chimps and the gorillas, it seems to me that instead of being dominated by the environment, hominids have at least become capable of holding their own against it. Over, say, the past 2.5 million years, weāve finally found ways to careen over the whole of the globe, from islands to wetlands to the high Andes. This is something the gorillas and chimps just canāt do. Thereās one line of thought that says this was a very recent phenomenon of the past 50,000 years related to increases in expression and communication possible only once the Neanderthals disappeared and got out of the way. And thereās another line, which I would tend to share, that argues that it was not so much an exponential curve that suddenly went around a right-angled bend and took off up to outer space, but it was a slow progression from about 2.5 million years ago. Now, if you take that line, then not only Neanderthals, but even Homo erectus are in some ways human rather than animal. All of these groups were becoming human.
Before the divergence, there was a common ancestral species that lived about 400,000 years ago in Africa and probably in the Middle East. When that common species eventually split, its African branch went on to become us and its European branch went on to become Neanderthals. To adapt to the colder conditions, Neanderthals developed specializations in their physiology: their bodies, for example, were very wide, very thick-set, very powerful, and very muscular. These adaptations also indicate that they were using their bodies more intensely and over a greater period of the day than we do. While Cro-Magnon brains were making the switch to becoming good at problem solving and finding short cuts, Neanderthals still had the predominance of brawn over brain. They were probably hunting at close quarters while modern humans were developing more efficient spears.