Read Masters of the Planet Online
Authors: Ian Tattersall
At Dmanisi itself, pollen studies indicate that just prior to its first occupation by hominids, southern Georgia had enjoyed a warm, damp climate supporting a rich mixed habitat of forested and grassy areas. But by the time the hominids actually appeared there a cooling and drying trend had begun to set in, expanding the areas of grassland and transforming the humid forests into formations of much more arid and crackly aspect. This is an environment that would have presented the hominids with a lower abundance of plant foods than their ancestors had benefited from back in Africa; but there is also evidence at Dmanisi of an extensive mammal fauna, including large herds of herbivores that the hominids must have exploited in some wayâas bashed-in and cut-marked mammal bones confirm.
One new aspect of life that would have confronted the hominids arriving at Dmanisi is a pronounced seasonality in temperatures as well as in humidity; and this climatic variation would have deeply affected the resources available to them at different times of year. This was not an easy environmental transition to make, and it almost certainly could not have been managed by a typical primate species. This enhances our picture of the Dmanisi hominids as rugged, adaptable generalists, able to cope with rapidly fluctuating conditions. Evidently the key to early hominids' success in Eurasia, then as now, was the unusual flexibility of behavior that had also been the hallmark of their African ancestors.
A particular surprise offered by Dmanisi came with the discovery of the fourth hominid skull to be recovered there. Known as D3444, this skull had belonged to an aged individual, thought to have been male, who was missing all but one of his teeth. It is not unusual to find fossil skulls that have lost their teeth subsequent to the death of their owner; but in the case of D3444 most of the missing dental elements had vanished long before his demise. Nearly all of his empty tooth sockets had already shriveled away, in a process that would have taken several
years
.
Front view of the toothless hominid skull from Dmanisi (D3444/D3900), about 1.8 million years old. This aged individual, presumed to have been male, had lost all of his teeth but one well before he died. It is thought that his survival may have required extensive help from other individuals, suggesting a social milieu of considerable complexity. Photograph of cast by Jennifer Steffey.
Especially if he and his kin had subsisted on a largely meat-based diet, this old male would have had great difficulty chewing his food; and the Dmanisi team believes that he would probably have starved without extensive help from other members of his social group (although he might conceivably have pounded meat with one of those rock cores to make it softer). Still, the argument that this highly disadvantaged individual had benefited from the long-term compassion of his relatives is, all in all, a plausible one: occasionally a chimpanzee manages to survive for a long period without teeth, but chimps eat a much softer diet than is probable for the Dmanisi hominids.
D3444 is by far the earliest example we have of an ancient hominid who somehow contrived to survive over a lengthy period with a major handicap. Indeed, the next oldest examples of disadvantaged individuals (these ones with evidence of cranial and brain deformities) are as much
as
a million years younger. That the aged Dmanisi male was capable of at least partly compensating for his physical disability by presumably cultural means has vague but powerful implications for cognitive complexity. What's more, if the Dmanisi researchers are correct in their surmise, D3444 also furnishes us with the first putative instance of social concern in the hominid record. Evidence for human empathy of this kind only becomes abundant very much later in time; but, given the spotty nature of the earlier record, this is maybe hardly surprising. What's more, compassionate behaviors are clearly as deeply ingrained in the human psyche as their opposites are; and it is even possible that we may glimpse the deep roots of such expressions in the consolation chimpanzees often offer to wounded or oppressed groupmates. What the apes most conspicuously lack, however, is the technical capacity to implement assistance; and it seems entirely reasonable to conclude that the Dmanisi hominids had the cognitive reserves to express their fellow-feeling in the form of material support. At the point when hominids first entered Eurasia they were evidently already beings of empathy, as well as of considerable resource and complexity.
MEANWHILE, BACK AT THE RANCH . . .
While hominids were busy spreading into other regions of the Old World, taking long-established ways of doing business with them, those that stayed behind in the parent continent were not standing still, at least technologically. As in Eurasia, the old ways continuedâtechnologies have always overlapped in time, as they continue to do todayâbut at about 1.5 million years ago archaeologists in Africa (and recently in India, too) begin to pick up regular evidence of an entirely new concept in stone tool making. For a million years, and probably more, the key idea in making stone implements had been to produce a smallish flake with a usable sharp edge; and it hadn't really mattered what those flakes, or the cores they were chipped from, had looked like. There was no aesthetic behind them; no notion even of basic form. The tool-making concept was totally a functional one: get that cutting edge.
Quite soon after
Homo ergaster
had come on the scene, however, all this changed dramatically with the appearance of what is known as
“handaxes.”
These stone tools are the emblem of what is known as the “Acheulean” culture, so-named for the site in France at which it was first recognized. Those handaxes are pretty late, howeverâthey are dated to well under half a million years agoâand the earliest examples of this tool type are currently known from a site in Kenya dated to some 1.78 million years ago. At that remove in time, however, handaxes are rather crudely made and extremely rare. They did not become a routine feature at archaeological sites until several hundred thousand years later.
Handaxes are much larger tools than their predecessors, and involve an entirely new notion of what a tool was. To make a handaxe, a stone “core” (in later times, itself a large flake) was elaborately shaped by multiple blows to both sides into a flat, symmetrical teardrop form. They are typically about eight or nine inches long, but may occasionally be much larger. Sometimes these tools are quite pointed, in which case they are called “picks”; in other instances they may be truncated by a straight edge, and are known as “cleavers.” But the basic teardrop handaxe shape is quite uniform, and huge quantities of these implements were produced throughout the African continent and eventually beyond.
A “cleaver” (left) and a “handaxe” from St. Acheul, in France, from which the Acheulean industry was named. Photo by Willard Whitson.
The
handaxe proved to be an extremely durable form: it was produced with little conceptual change, although with some later refinements in manufacturing, for well over a million years. Indeed, this implement has earned the sobriquet of “Swiss Army Knife of the Paleolithic” for its evidently many uses. Studies of how handaxes became worn in the course of such uses have shown that they were employed for tasks as diverse as cutting tree branches, slicing meat, and scraping hides. And the stability of the handaxe's form indicates just how all-purpose these tools were, even as the habitats their makers occupied changed dramatically from moist to arid and back again, sometimes on incredibly short time scales.
Making Oldowan flakes had required a considerable sophistication in choosing the stone to be chipped: coarser-grained rock was less suitable for producing or holding that slicing edge. Volcanic glass, flints, and cherts, or even fine-grained lavas would do the trick, and these materials were assiduously chosen when possible. The earliest stone tool makers clearly knew good rock when they saw it, and as we've already seen they often carried it around for long distances in anticipation of needing it in places where none might be available. But the handaxe makers faced a yet more complicated situation than the Oldowans had. Not only did the rock have to be of the right
kind,
but the individual piece of rock had itself to be suitable, free of flaws that would foil the predictable flaking sequence needed to produce a shaped utensil. So not only did the toolmaker need to be able to “see” the finished form in the rock before flaking started, but he or she needed to ensure that the core itself was sufficiently homogeneous to support the complex sequence of actions necessary. Clearly, this has profound if unclear implications for Acheulean mental abilities.
I've already mentioned that one of the most insuperable problems we have in our efforts to understand the cognitive background of any radical innovation such as handaxe making, is that we modern humans find it virtually impossible to imagine any state of consciousness other than our own. Even with the greatest effort of will we simply cannot put ourselves in the cognitive place of our predecessors, because the cognitive systems of those early hominids were clearly not simply scaled-down versions of ours. So we can't get to where the early handaxe makers
were
by mentally ratcheting down our IQs a notch or three: and we will certainly be on the wrong track if we think that Acheulean tool makers were simply like us, but (because they had smaller brains) dumber. Indeed, if that had been the case they would almost certainly have had a very difficult time getting by. Doing business the way we do it demands the specific kind of smarts that we have; and our symbolic way of processing environmental stimuli seems to have been a remarkably recent acquisition. Without any doubt, the early handaxe makers' subjective experience of the world, and their way of dealing with information coming in from it, were
different
in some major qualitative way from ours.
Limited as our speculations have to be, however, the conclusion is inescapable that the invention of the handaxe must have representedâ or at least have reflectedâa cognitive leap of some kind relative to the bipedal apes that had made the first stone tools. Making uniform objects according to a set of rules, as the handaxe makers did, implies obeisance to a collective appreciation of what is good and appropriate, and it has sometimes been considered to mark the boundary between “protohuman” and “human” behaviors. But just what did the cognitive change implied here mean in terms of what was actually going on in the heads of the hominids concerned? What did it reflect in terms of the way they apprehended and responded to the world? Unfortunately, there is nothing in the material record to suggest any answers.
Uncertainty as to what was going on is exacerbated by several other factors. For one thing, the invention of the handaxe seems to have taken place after
Homo ergaster
appeared. This is actually not surprising because, as I remarked in chapter 6, the technological advances that provide our best clues to cognition at this stage must have been made
within
a hominid species, if for no better reason than there was nowhere else for them to occur. Clearly, the intellectual potential for envisioning that a specific, realizable teardrop form lay within a lump of stone must have been present in the physical brains of the handaxe makers
before
they started expressing it. Still, the identity of the inventors of this new technology remains a bit hazy, if only because of the probability that there is more than one distinct species among the spectrum of hominid fossils generally allocated to
Homo ergaster
(let alone to the all-embracing
Homo erectus
); and, if so, we have no idea of who was
doing
what. The current state of our knowledge merely allows us to be certain that a spirit of innovation was astir among early
Homo
in the African continent beginning well over 1.7 million years ago. And this is quite probably the most important thing to know, especially since there is no evidence that more than one hominid
grade
was involved in the process of technological advancement.