The media is reporting rather breathlessly a new find out of Arabia which seems to push much further back the presence of anatomically modern humans in this region (more accurately, the archaeology was so sparse that assessments of human habitation seem to have been made in a vacuum due to absence of evidence). Here is the major objection:
This idea is at odds with a proposal advanced by Richard Klein, a paleoanthropologist at Stanford University, that the emergence of some social or behavioral advantage — like the perfection of the faculty for language — was required for modern humans to overcome the surrounding human groups. Some kind of barrier had to be surmounted, it seems, or modern humans could have walked out of Africa 200,000 years ago.
Dr. Klein said that the Uerpmann team’s case for an earlier out-of-Africa expansion was “provocative, but in the absence of human remains, it’s not compelling.”
The stone tools of this era are all much alike, and it is hard to tell whether early modern humans or Neanderthals made them. At the sites of Skhul and Qafzeh in what is now Israel, early modern humans were present around 100,000 years ago and Neanderthals at 60,000 years, but archaeologists cannot distinguish their stone tools, Dr. Klein said.
A warmer and wetter climate around this time let modern humans get as far as Israel but apparently no farther, and the new findings from Jebel Faya could represent a second limited excursion. But in this case, it is Africa that is expanding, or at least the African ecological zone, and not modern humans, Dr. Klein said. “The key issue is whether this is an early out-of-Africa movement, but if so, it was far more limited than the modern human expansion to Eurasia roughly 45,000 years ago,” he said.

Image credit: Maathias Kabel
In The Dawn of Human Culture Richard Klein argued that modern humans as we understand them today, protean and highly cultural creatures, are a product of a biological change which reordered our cognitive faculties. Klein pinpoints this change to the “Great Leap Forward” ~50,000 years ago. But, there is a large gap in time between anatomically modern humans, who were resident in Africa nearly ~200,000 years ago, and behaviorally modern humans, who engage in the symbolic cultural production which we perceive to be the hallmarks of humanity. As against this particular model there have always been “gradualists,” who argue that there was no discontinuous biological change which resulted in the shift toward hyperactive cultural production. Stephen Oppenheimer makes the case for this in his book The Real Eve. Oppenheimer suggests that there was a gradual and cumulative cultural evolution. He argues that a proper analogy might be the rate of cultural change in the 20th century vs. than in the 17th century. Obviously we know that genetic evolution can not explain most of the difference in rate of change across the two eras, but looking at archaeological remains from the two periods would make clear their stark differences to a third party observer to the point where I can’t help but think a biological rationale would seem plausible without any other information.
I have no particular brief for either position in this post. I assume that both the biological and cultural models are too extreme now. The long term persistence of the Oldowan culture in much of the world implies to me that there may have been a biological chasm between hominin groups, and that the Oldowan “culture” was somehow biologically encoded. And yet I am not convinced that the gap between our Neandertal and neo-African ancestors was as great as Klein would have us believe. So now to the paper. First, let’s look at the abstract:
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