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Mouth Main site, and others) contain many more bones of fish and airborne birds than do Last Interglacial MSA sites (Blombos Cave and Klasies River Mouth Main site). Only LSA sites contain “fish gorges”
(polished, toothpick size, double-pointed bone splinters), grooved stone net sinkers, and other implements that recall ethnographically recorded fishing and fowling gear. Archeological evidence thus reinforces the conclusion that only LSA people fished and fowled routinely. Greater LSA ability to catch fish and birds would surely have promoted larger LSA populations.
Second, in Present Interglacial LSA sites (Nelson Bay Cave, Byneskranskop Cave 1, and others), buffalo and wild pigs outnumber eland, roughly mirroring the abundance of buffalo and wild pigs in the historic environment. In contrast, in Last Interglacial MSA sites (Klasies River Mouth Main site and Blombos Cave), eland greatly outnumber buffalo and pigs, even though historic observations imply that eland were probably much rarer nearby. Eland continue to dominate in MSA layers that date from the early part of the Last Glaciation (Klasies River Mouth Main site and Die Kelders Cave 1), which increases the probability that eland dominance reflects MSA behavior and not some undetected environmental factor. Since eland are much less dangerous to hunt than buffalo and wild pigs, and since MSA sites lack firm evidence for projectile weapons, an MSA preference for eland may actually reflect MSA reluctance to attack species that were especially likely to injure hunters. LSA people almost certainly had projectile weapons, arguably including the bow and arrow from 20,000 years ago, and they could thus have stalked buffalo and wild pigs at significantly reduced personal risk. If this deduction is correct, and buffalo and pigs were more common than eland on the ground near both MSA and LSA sites, 07 Body before Behavior.r.qxd 1/29/02 5:06 PM Page 239
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LSA people would have obtained many more animals overall, even if their hunts were often unsuccessful. Again, a likely result would be larger LSA populations.
Third, the tortoises, shellfish, or both in MSA sites (Klasies River Mouth Main site, Blombos Cave, Die Kelders 1, Ysterfontein, Hoedjies Punt, Sea Harvest, and Boegoeberg 2) tend to be much larger than those in LSA sites (Nelson Bay Cave, Die Kelders Cave 1, Byneskranskop Cave 1, Kasteelberg A and B, Elands Bay Cave, and others) that were occupied under similar environmental conditions.
Since tortoises and shellfish can be collected with limited technology and minimal risk, the smaller average tortoise and shellfish size in LSA sites probably reflects more intensive LSA collection that understandably removed the largest individuals first. The most plausible explanation for more intensive collection is that LSA collectors were more numerous, in keeping with their ability to fish, fowl, and hunt more effectively.
Fourth, the ages of fur seals in LSA sites (Elands Bay Cave, Kasteelberg A and B, Die Kelders 1, Nelson Bay Cave, and others) suggest that the people timed their coastal visits to the August-to-October interval when 9- to 10-month-old seals could be harvested on the shore and when resources inland were probably at their poorest. The ages of MSA fur seals suggest that MSA people remained at the coast more or less throughout the year, even when resources were probably more abundant inland. This difference is the most weakly substantiated of the four listed here, since only the Klasies River Mouth Main site has provided a large enough MSA seal sample for numerical comparison to the LSA samples. If fresh MSA samples confirm a likely MSA/LSA contrast in seasonal mobility, a reasonable explanation is that MSA 07 Body before Behavior.r.qxd 1/29/02 5:06 PM Page 240
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people could not transport water effectively. So far, only LSA sites have provided secure evidence for water containers, in the form of ostrich eggshell canteens.
In sum, the South African sites suggest that LSA technological advances contributed directly to an enhanced ability to hunt and gather and that this in turn promoted larger human populations.
Unfortunately, it is not yet possible to show that the hunting-gathering advance occurred abruptly in the earliest LSA, tentatively dated between 50,000 and 40,000 years ago, rather than more gradually afterwards. The issue will ultimately have to be addressed outside the coastal regions of South Africa, since these areas were largely abandoned between 60,000 and 30,000 years ago, probably because of the regional aridity to which we have already referred. Still, pending fresh research elsewhere, the South African evidence is certainly sufficient to argue that MSA animal remains, like MSA artifacts, imply less than fully modern behavior. If we accept that MSA people were anatomically modern or near-modern, then the artifacts and animal remains together suggest that modern anatomy lagged modern behavior by at least 50,000 years and that it was the evolution of modern behavior between 50,000 and 40,000 years ago that allowed anatomically modern people to spread from Africa.
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University of Stellenbosch, and, writing together, Sally McBrearty of the University of Connecticut and Alison Brooks of George Washington University. In their opinion, the real advance to modern behavior occurred with the appearance of the MSA. This conclusion eliminates the nagging need to explain why modern (LSA) behavior lagged behind modern (MSA) anatomy, since they would have arisen together, 250,000 to 200,000 years ago. It then fails, however, to confront the equally knotty problem of why the modern human diaspora to Eurasia lagged behind modern anatomy by 50,000 years or more.
The idea that MSA people were behaviorally modern is founded mainly on two observations. The first is that MSA and LSA people shared prominent evolved behaviors such as a sophisticated ability to produce and modify sharp stone flakes and blades, regular hunting of large mammals for food, an interest in collecting and modifying naturally occurring lumps of pigment (ocher), and the capacity to construct fireplaces routinely. The second is that MSA people sporadically exhibited some of the same advanced behaviors that LSA people usually did, including especially the manufacture of standardized, ground or polished bone artifacts.
We agree that MSA and LSA populations shared many evolved, uniquely human behaviors, such as the use of naturally occurring pigments and the routine construction of fireplaces. However, Mousterian populations in Europe also possessed these traits, and future research may show that later Acheulean people did too. In this case, Mousterians in Europe and MSA people in Africa could have inherited the behaviors from their last shared ancestor, and the key question is whether they lacked other behaviors that only LSA and Upper Paleolithic people shared with historic hunter-gatherers. If so, it is 07 Body before Behavior.r.qxd 1/29/02 5:06 PM Page 242
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certainly reasonable to conclude, as we have, that MSA and Mousterian people were behaviorally evolved in the direction of modern humans, but that they were still not fully modern.
The case that MSA people occasionally manufactured sophisticated bone artifacts depends primarily on findings at two localities: the Katanda riverside sites in the Democratic Republic of the Congo and Blombos Cave in South Africa. At Katanda, ESR dates on hippopotamus teeth and luminescence dates on covering sands bracket mammal and fish bones, non-diagnostic stone artifacts that could be either MSA or LSA, eight whole or partial barbed bone points (“harpoons”) (Figure 7.10), and four additional formal bone artifacts between 150,000 and 90,000 years ago. At Blombos Cave, luminescence dates on overlying sands indicate that numerous mammal bones and shells, occasional fish bones, classic MSA stone artifacts, two or three whole or fragmentary, symmetrical, polished bone points, and about twenty-five less formal bone artifacts accumulated before 70,000 years ago.
The Katanda and Blombos findings cannot be summarily dismissed, but they require additional substantiation before the MSA is radically reinterpreted. At Katanda, the most important issue that requires clarification is why the bone artifacts appear relatively fresh while the associated mammal bones are heavily abraded and rounded, as if they had been transported in a stream. The implication might be that the artifacts accumulated after the bones and that the age of the artifacts has been significantly overestimated. This possibility might be
FIGURE 7.10
Barbed bone points from Katanda, Democratic Republic of the Congo (redrawn after J. E.
Yellen 1998,
African Archaeological Review
15, p. 189).
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0
0
5 cm
2 in
Katanda
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checked by determining if the bone artifacts and animal bones differ in geochemical content or by direct radiocarbon dating of the artifacts.
Elsewhere in Africa, radiocarbon dates suggest that similar bone artifacts are mostly younger than 12,000 years.
At Blombos Cave, there is the problem that the polished bone points came from a part of the deposit where radiocarbon dates indicate that MSA and much younger LSA deposits were mixed. In chemical composition, the bone points resemble MSA bones more closely than LSA bones, but bone preservation varies across the surface at Blombos Cave, and the MSA bones for comparison came from the same admixed deposits as the polished points. These deposits also produced fish bones in quantities that are otherwise known only in LSA layers.
In contrast, in parts of the Blombos excavation where admixture can be ruled out, the MSA layers contain many fewer fish bones, and these come mainly from large individuals that could represent occasional beach wash-ups.
If the sophisticated Katanda and Blombos bone artifacts are accepted at face value, archeologists must then explain why the advanced behavior they represent remained isolated for tens of thousands of years before becoming commonplace in other LSA locations.
This is an especially difficult question to answer, if, as seems likely, such bone artifacts conferred an adaptive advantage, because they were used for purposes that stone tools could not perform or could not perform as well. In this light, it is hard to understand, for example, why the MSA occupants of Blombos Cave would have produced polished or ground bone points when their nearby MSA contemporaries at Die Kelders Cave 1, Boomplaas Cave, Klasies River Mouth, and other sites did not. The contrast is unlikely to reflect differences in sample size, 07 Body before Behavior.r.qxd 1/29/02 5:06 PM Page 245
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because the other sites have provided many more MSA animal bones than Blombos Cave, while LSA bone assemblages that are smaller than the Blombos assemblage often contain many more formal bone artifacts. They also contain bone manufacturing waste and incompletely formed intermediate pieces (preforms) that Blombos Cave lacks. The answer may be that the Blombos MSA polished points actually derive from overlying LSA layers.
The Blombos case raises the point that there will always be some evidence for LSA/Upper Paleolithic behavior in MSA/Mousterian contexts, if only because even the most careful excavations may fail to detect occasional LSA/Upper Paleolithic intrusions into MSA/
Mousterian layers. Archeologists must then decide whether sporadic exceptions, ordinarily involving a small number of pieces, truly contradict a widespread pattern. Until the exceptions are repeatedly replicated to form a pattern of their own, it is surely fair to argue no.
For the moment then, we stand behind our view that the LSA/Upper Paleolithic represents a qualitative advance over the MSA/Mousterian, and that this advance explains why LSA/Upper Paleolithic people became so much more successful.
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years ago and that it underlay the subsequent expansion of modern Africans to Eurasia. The answer of course depends partly on whom you ask, but as we see it, there is only one set of developing observations 07 Body before Behavior.r.qxd 1/29/02 5:06 PM Page 246
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that could seriously challenge our position. These come from what may seem to be a particularly unexpected quarter—the island continent of Australia, and they concern the time when the first Australians arrived.
To begin with, we should emphasize that despite its geographic isolation, Australia has often played a central role in discussions of modern human origins. This is mainly because anthropologists like Milford Wolpoff of the University of Michigan and Alan Thorne of the Australian National University have repeatedly argued for an evolutionary link between ancient Indonesian
Homo erectus
and the historic Australian aborigines, based on perceived similarities in skull form.
Genetic analyses now show, however, that the perceived similarities do not imply such a link, since after a decade of intensive analysis, no population in eastern Asia or anywhere else outside of Africa has been shown to possess a gene that cannot be traced to a recent African ancestor. The implication is that all living humans shared such an ancestor and that
Homo erectus
and other non-modern Eurasian populations contributed few if any genes to living humans.
A survey of the Y-chromosome published in
Science
magazine in May 2001 is particularly telling. The authors examined Y-chromosomes from 12,127 men representing 163 historic Asian populations, including Australian aborigines, and they showed that Y-chromosome variability can be traced to a single type “which originated in Africa about 35,000 to 89,000 years ago.” They go on to say that “the data do not support even a minimal
in situ
hominid contribution in the origin of anatomically modern humans in East Asia.” One of the oldest known Australian human fossils—the Mungo 3 skeleton—did possess a kind of mitochondrial DNA (mtDNA) that is unknown anywhere today, but it is only barely outside the living human range. We previously stressed 07 Body before Behavior.r.qxd 1/29/02 5:06 PM Page 247
