|Pinnacle Point Caves (PPC) in relation to Klasies River Mouth (KRM) cave and Blombos Cave (BBC), three of the best known southern African localities with modern human accoutrements as early as 70 ka to 100+ ka.|
|Three representations of the stratification at Pinnacle Point PP5-6. Source: Brown et al. 2012|
For example, does one conclude that the real age of this stratigraphic column ranges from 53 ka to 78 ka? How about 53 ka to 69 ka? Or 60 ka to 69 ka? Moreover, with such variance from what one should expect of the age succession in a sedimentary column that has maintained temporal integrity, how do we know that any of these estimates are accurate? All this points to, in my barely savvy opinion, serious difficulty with the technique, most likely due to the intractable problem inherent in the primary assumption of the technique. And, if the very latest results of the best of the best practitioners yields such shaky outcomes, what does it say about all of the other South African site chronologies? Here, then, lies the very real possibility that the OSL technique is single-handedly creating a false picture of modern human origins throughout the southern region.
|Stratigraphic profile of La Quina, the type site of the Quina Mousterian. All of the objects illustrated are éboulis, clasts of all sizes and shapes, which have spalled off the bedrock and been incorporated along with the archaeological materials.|
In making this comparison between éboulis analysis and the OSL dates from southern Africa, I don't mean to suggest that the two techniques are equal. Rather, I make the comparison because, in the past, an error-prone technique was used to provide the chronological framework for an entire sub-continent. That's the direct comparison to be made. The southern African cave sites are universally dated using OSL or other equally shaky [to my mind] techniques.
|The crux of the southern African OSL dates. In relation to the earliest evidence of modern human behaviour everywhere outside of Africa, and the speed at which Eurasia was 'colonized', the southern African dates stand out like a sore thumb.|
Take, for example, the overwhelming evidence for the almost instantaneous spread of behaviorally modern humans to the furthest reaches of Asia, which happened about 45 ka. Australia was colonized at this time. So were some of the the furthest reaches of Europe--England, for example, at 44 ka. The best explanation for the absence of modern human archaeological assemblages prior to this time is that there simply were no modern humans outside of Africa prior to that time. The question thus becomes, if humans could expand the length and breadth of Asia in an eye-blink of geological time, why didn't it happen earlier, when modern human behaviour is claimed to have had its start 70 ka to 90 ka ago in southern Africa?
To explain the apparent lag between the emergence of modern human behaviour in southern Africa and that which inhered everywhere else in the world post 45 ka, the various archaeological teams must invoke untested, and indeed untestable hypotheses as to the reason for those moderns staying put for anywhere between 164 ka and [taking the youngest date from PP5-6] 53 ka. One hypothesis has that population bottlenecks occurred due to environmental circumstances [as yet unrecorded], after which cultural achievements of the modern populations were stultified, only to reappear some 30,000 years later, at which time the archaeology records the rapid spread of modern humans throughout what's been called the Old World.
In July of this year we saw a report from Border Cave of a modern human archaeological assemblage that dates to about 44 ka, a result in accord with the beginning of modern human behaviour in Eurasia. But, because they found no earlier deposits, the authors find it necessary to replay the tape of the 'early' teams, that the Border Cave moderns must represent the hypothesized re-fluorescence of modern humans preparatory to world domination. Once again. I think such intellectual reaching is unnecessary, at best, and obfuscatory at worst. I do not mean to suggest that the obfuscation is deliberate. The archaeologists who rely on OSL age estimates have nothing else to go on. Or, at least, they have no reason to think that their information is in error. After all, the best of the best are working at Pinnacle Point. Who could doubt their veracity? Who would, much less?
|Modern human artifacts from Border Cave at 44 ka. Touted to be the earliest evidence for the same culture that existed ethnographically in the vicinity of Border Cave. [Take that with an anthropological grain of sand.] Source: D'Errico et al. 2012.|
I supposes one could suggest that there were natural barriers to their spread out of southern Africa. But, there are no natural barriers to movement in coastal Africa, nor would there have been when the sea levels were depressed during the glacial stages of the Pleistocene. If they could process pigments and decorate ochre, make beads, and arrows, they were equally capable of making boats to cross the broad reaches of Africa's rivers where they meet the sea. After all, the colonizers of Australia crossed at least 90 km of open ocean at around 45 ka. Surely the precocious moderns in south Africa at 70 ka to 90 ka could have done the same. So, the big question is why did they stay put in southern Africa? Huh? Riddle me that, Batman. Apparently the Wall Street Journal has a suggestion.
So, you see, reason alone tells me that there's much wrong about the early dates from southern Africa. And my instinct tells me that the OSL dates must be wrong. As I've said to you before, will some kindly physicist not come forward to examine the mathematical filmflammery that accompanies OSL age estimates, and thereby save me from this empirical purgatory??? The flimflammery in question.
Please??? I'm beggin' ya.
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