Wednesday, November 3, 2010

A Setback for Neanderthal Smarts? Not

My issue with this article is that I have no problem expanding the Chatelperronian to include dates from 21k to 49k and still associate it with Neanderthals.
We know that there weren't any Hss in France 49k ago....and we know that there were still neanderthals in southern Iberia 21k ago...and we know that neanderthals definitely mixed with Hss.
So late Chatelperronian in France doesn't really seem outlandish to me, and I'd be willing to bet that whoever made those lithics 21k ago had more than any modern person's share of neanderthal blood in them.


A Setback for Neandertal Smarts?
by Michael Balter on 18 October 2010, 3:00 PM | Permanent Link | 0
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Neandertals are looking sharp these days. Many researchers now credit
our evolutionary cousins, once regarded as brutish and dumb, with
"modern behavior," such as making sophisticated tools and fashioning
jewelry, a sign of symbolic expression. But new radiocarbon dating at
a site in France could mar this flattering view. The study concludes
that the archaeological layers at the site are so mixed up that
ornaments and tools once attributed to Neandertals could actually be
the work of modern humans, who lived in the same cave at a later date.


One prominent researcher even argues that this celebrated site, the
Grotte du Renne (literally "reindeer cave") at Arcy-sur-Cure in
central France, should now be eliminated from scientific
consideration. "This key site should be disqualified from the debate
over [Neandertal] symbolism," says Randall White, an archaeologist at
New York University. But João Zilhão, an archaeologist at the
University of Bristol in the United Kingdom who has often tussled with
White and other researchers over the evidence from the Grotte du
Renne, says that the new study "prove[s] the exact opposite of what
[its] authors claim."


The Grotte du Renne was excavated between 1949 and 1963 by the late
French prehistorian André Leroi-Gourhan, who found 15 levels of
hominid occupation ranging from about 45,000 to 28,000 years ago. This
period includes the overlapping occupation of Europe by Neandertals,
who show up about 130,000 years ago and disappear no later than 30,000
years ago, and modern humans, who arrived in Europe between 45,000 and
40,000 years ago and stayed for good.


Leroi-Gourhan attributed the artifacts in the lowest levels to
Neandertals and artifacts from higher levels to modern humans, based
largely on the types of tools they made. But the middle layers at the
site included bone tools, ivory ornaments, and other sophisticated
artifacts that Leroi-Gourhan attributed to a culture called the
Châtelperronian. Although Châtelperronian artifacts closely resemble
those made by modern humans, many researchers have attributed them to
Neandertals because they have sometimes been found with Neandertal
fossils. Indeed, at the Grotte du Renne, Leroi-Gourhan found about 30
Neandertal teeth in the Châtelperronian levels, which can be
distinguished from modern human teeth based on the size and shape of
their cusps and other features.


Most debates about the Châtelperronian—which begins about 40,000 years
ago—have revolved around whether Neandertals invented it or simply
copied the behavior of incoming modern humans. But recently, some
researchers have begun questioning whether Neandertals made the
Châtelperronian at all.


In the new study, published online today in the Proceedings of the
National Academy of Sciences, a team led by dating expert Thomas
Higham of the University of Oxford in the United Kingdom reports 31
new radiocarbon dates from the Grotte du Renne, using new filtration
methods to purify radiocarbon samples and remove contamination by
modern carbon sources, which has long plagued dating accuracy. The
dates, obtained on materials such as bone tools and ornaments made of
animal teeth, painted a disturbing picture: Whereas upper layers
attributed to modern humans clocked in at no older than 35,000 years,
artifacts from the Châtelperronian levels ranged from 21,000 years
ago, when Neandertals were long extinct, to 49,000 years ago, before
the Châtelperronian actually began. Indeed, Higham and his colleagues
found that at least one-third of the Châtelperronian dates were
outside the known time period of this culture.


The team concludes that the archaeological levels must have become
mixed over thousands of years and that younger artifacts made by
modern humans may have moved down into levels long thought to be
associated with Neandertals. "The evidence from the Grotte du Renne
ought to be viewed with extreme caution," the authors write.


The authors do not speculate on whether the layers became mixed
through natural sedimentation processes or excavation errors that
caused some artifacts to be assigned to the wrong occupation levels.


White says that the results should not be surprising, because Leroi-
Gourhan's excavations took place "at a time when excavation techniques
in general were rudimentary." He adds that only one other
Châtelperronian site has produced personal ornaments, in much smaller
numbers, meaning that claims that Neandertals were capable of such
symbolic expression rests heavily on the evidence at the Grotte du
Renne. But Zilhão counters that two-thirds of the dates are consistent
with Neandertals having made the Châtelperronian. The other, outlying
dates could be the result of contamination rather than mixing of
artifacts among layers, he says.


Yet Higham, who has been redating nearly 20 other Neandertal and
modern human sites in Europe, says that the Grotte du Renne is unique
in producing such wildly varying dates. "I think this is telling us
something," Higham says. "This site has some problems."

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