Doubt cast on Tam Pa Ling age

For reference, see the post on the original article:

• Tam Pa Ling: modern humans in Southeast Asia at 63-46ka

From a criticism of the original paper:

Hence, contrary to the authors' assertion that TPL1 has a “minimum secured age of 46 ka and a maximum age of ∼63 ka”, the published stratigraphy, if correct, indicates that the TPL1 specimen is no older than 46 ka. TPL1’s status as “the earliest well-dated modern human fossil east of the Jordan Valley” also appears weak compared with the Liujiang specimen dated to ∼153 ka (3), the Callao Cave fossil in the Philippines dated to 67 ka (4), and, above all, the ∼100 ka modern fossil from Zhirendong (5), discovered only 484 km northeast of Tam Pa Ling in Southern China.

Irreconcilable differences between stratigraphy and direct dating cast doubts upon the status of Tam Pa Ling fossil 

Alain Pierret et al.

Link

... and from a reply to the criticism by the authors:

They question the validity of the dating because of an apparent “reverse stratigraphy” (Fig. 1), whereby “older” dates are located higher in the section [i.e., 51.4 (14C) at 2.1 m] and “younger” dates are at the bottom of the section [i.e., 48 ka (optically stimulated luminescence [OSL]) and >49.2 ka (14C) at 4.3 m] (2). This criticism ignores the presented SEs (table 2 and table S1 in ref. 1), which make the results statistically equivalent (Table 1). More importantly, they ignore that the radiocarbon results are well beyond the accepted radiocarbon barrier of ∼40 ka (3), indicating that the charcoal has a minimum age of ∼40 ka. Bearing in mind these problems, we have conservatively estimated the burial age to be ∼46 ka according to the luminescence dating of the sediments. As the luminescence results are stratigraphically consistent, we perceive no irreconcilable differences between the stratigraphy and dating. 

... 

Finally, we interpret TPL1 as the earliest human fossil that is both well-dated and fully modern in morphology. Zhirendong demonstrates a mixture of archaic and modern traits, making it significant but not fully modern in appearance (4). Similarly, the metatarsal from Callao Cave is only diagnostic to the genus Homo given that it falls within “the morphological and size ranges of Homo habilis and H. floresiensis” (ref. 5, p. 123). Although the modernity of the Liujiang fossil is not questioned, it has no direct date and no secure stratigraphic provenance. It has been variably dated to ca. 20 ka, ca. 67 ka, 111 to 139 ka, and >153 ka (6), and this uncertain stratigraphic context has prevented many scholars from accepting any of the dates currently attributed to it (6).

Reply to Pierret et al.: Stratigraphic and dating consistency reinforces the status of Tam Pa Ling fossil 

Fabrice Demeter et al.

Link

Tam Pa Ling: modern humans in Southeast Asia at 63-46ka

I have become convinced that the roots of the Eurasian dispersal occurred at around 70 thousand years ago, from an earlier population of modern humans that had left Africa for the Levant and Arabia before 100 thousand years. So, the discovery of a new anatomically modern human from Southeast Asia that is directly dated to 63ka and can be no younger than 46ka is a welcome addition to the record.

The Tam Pa Ling skull would be of similar age to the Liujiang skull from China if the latter's 68ka age is accepted. So, now the case is much more secure for the presence of modern humans in the Far East in the interval between the 70ka Event, and the post-50ka symbolic revolution associated with the MP/UP transition. If we add to the equation the presence of an UP European-like skull at Qafzeh in Israel at ~100ka, and of the Nubian Complex in South Arabia at ~106ka,  it is becoming increasingly difficult to accept ideas about either a 60ka coastal migration, or a late Out-of-Africa migration associated with the Upper Paleolithic that somehow replaced the people who lived all over Eurasia.

From the press release:

"It's a particularly old modern human fossil and it's also a particularly old modern human for that region," said University of Illinois anthropologist Laura Shackelford, who led the study with anthropologist Fabrice Demeter, of the National Museum of Natural History in Paris. "There are other modern human fossils in China or in Island Southeast Asia that may be around the same age but they either are not well dated or they do not show definitively modern human features. This skull is very well dated and shows very conclusive modern human features," she said. 

No other artifacts have yet been found with the skull, suggesting that the cave was not a dwelling or burial site, Shackelford said. It is more likely that the person died outside and the body washed into the cave sometime later, she said. 

The find reveals that early modern human migrants did not simply follow the coast and go south to the islands of Southeast Asia and Australia, as some researchers have suggested, but that they also traveled north into very different types of terrain, Shackelford said.

UPDATE (Aug 27): Coverage in Hominid Hunting.

PNAS doi: 10.1073/pnas.1208104109

Anatomically modern human in Southeast Asia (Laos) by 46 ka

Fabrice Demeter et al.

Uncertainties surround the timing of modern human emergence and occupation in East and Southeast Asia. Although genetic and archeological data indicate a rapid migration out of Africa and into Southeast Asia by at least 60 ka, mainland Southeast Asia is notable for its absence of fossil evidence for early modern human occupation. Here we report on a modern human cranium from Tam Pa Ling, Laos, which was recovered from a secure stratigraphic context. Radiocarbon and luminescence dating of the surrounding sediments provide a minimum age of 51–46 ka, and direct U-dating of the bone indicates a maximum age of ~63 ka. The cranium has a derived modern human morphology in features of the frontal, occipital, maxillae, and dentition. It is also differentiated from western Eurasian archaic humans in aspects of its temporal, occipital, and dental morphology. In the context of an increasingly documented archaic–modern morphological mosaic among the earliest modern humans in western Eurasia, Tam Pa Ling establishes a definitively modern population in Southeast Asia at ~50 ka cal BP. As such, it provides the earliest skeletal evidence for fully modern humans in mainland Southeast Asia.

Link

Genetic structure in China

After my experiment on Spain, I decided to carry out a similar experiment in China, for which there is a large number of regional/ethnic sub-populations.15 clusters were inferred with 22 MDS dimensions.

The Uygur are the clear outlier population, doubtlessly due to their substantial Caucasoid admixture and geographical position in Central Asia, a region that was traditionally at the outskirts of Chinese civilization. Other Altaic speakers (both Mongolic and Tungusic) are also divergent, as are the Dai/Lahu people from the China/Thailand/Laos area.

Interestingly, the Tujia people from Central China seem to be the ones most like the Han overall, with Hmongic Miaozu/She more like the southern Han.