A very interesting paper by Liu, W. et al. in Nature The earliest unequivocally modern humans in southern China http://dx.doi.org/10.1038/nature15696 (2015) reports having found modern human teeth in Southern China that are at least 80,000 years old, and up to 120,000 years old. This is clearly at odds with other papers that suggest a much later "Out Of Africa" event.
The Abstract reads:
"The hominin record from southern Asia for the early Late Pleistocene epoch is scarce. Well-dated and well-preserved fossils older than ~45,000 years that can be unequivocally attributed to Homo sapiens are lacking. Here we present evidence from the newly excavated Fuyan Cave in Daoxian (southern China). This site has provided 47 human teeth dated to more than 80,000 years old, and with an inferred maximum age of 120,000 years. The morphological and metric assessment of this sample supports its unequivocal assignment to H. sapiens. The Daoxian sample is more derived than any other anatomically modern humans, resembling middle-to-late Late Pleistocene specimens and even contemporary humans. Our study shows that fully modern morphologies were present in southern China 30,000–70,000 years earlier than in the Levant and Europe. Our data fill a chronological and geographical gap that is relevant for understanding when H. sapiens first appeared in southern Asia. The Daoxian teeth also support the hypothesis that during the same period, southern China was inhabited by more derived populations than central and northern China. This evidence is important for the study of dispersal routes of modern humans. Finally, our results are relevant to exploring the reasons for the relatively late entry of H. sapiens into Europe. Some studies have investigated how the competition with H. sapiens may have caused Neanderthals’ extinction (see ref. 8 and references therein). Notably, although fully modern humans were already present in southern China at least as early as ~80,000 years ago, there is no evidence that they entered Europe before ~45,000 years ago. This could indicate that H. neanderthalensis was indeed an additional ecological barrier for modern humans, who could only enter Europe when the demise of Neanderthals had already started."
In the article (by some odd miracle I was granted Online access to the article by the nature.com content sharing initiative) it mentions that: "This evidence could support different origins and/or dispersal routes for modern humans across Asia". And indeed it does. Here we have humans in China 80 to 120 kya while they failed to reach Europe until 35 to 75 kya. The authors attribute this to the fact that: "... the possibility that H. Neanderthalensis was for a long time and additional barrier for modern human's expansion...".
An article by E. Callaway also in Nature includes this interesting comment: "Although Hublin says there is a good case that the Daoxian teeth are older than 80,000 years, he notes that several of the teeth have visible cavities, a feature uncommon in human teeth older than 50,000 years. “It could be that early modern humans had a peculiar diet in tropical Asia,” he says. “But I am pretty sure that this observation will raise some eyebrows." Martinon-Torres says her team plans to look more closely at the cavities and the diet of the Daoxian humans by examining patterns of tooth wear."
Dental cavities are much older than mankind. Cavities have been found in a distant relative, the Paranthropus robustus, that lived in Africa 2 million years ago. However the bacteria that causes tooth decay seems to have become more prevalent among humans after the invention of agriculture. Perhaps because it provided more carbohydrates in the diet, a good source of sugars for the tooth-decay bacteria. Nevertheless, a diet with plenty of fruit in subtropical China could also cause cavities.
The idea of an ancient dispersal out of Africa and admixture in Asia with even more archaic migrants is not new and has recently received support (see: Early modern human dispersal from Africa: genomic evidence for multiple waves of migration (2015), Francesca Tassi, Silvia Ghirotto, Massimo Mezzavilla, Sibelle Torres Vilaça, Lisa De Santi, Guido Barbujani. doi: http://dx.doi.org/10.1101/022889). However others have contended that dispersal took place only recently (See: Levantine cranium from Manot Cave (Israel) foreshadows the first European modern humans (2015), Israel Hershkovitz, et al., Nature 520, 216–219 (09 April 2015) doi:10.1038/nature14134) some 60 to 40 thousand years (kyr) before present (BP) as demonstrated by the former oldest remains of modern H. sapiens outside of Africa at Manot Cave (Western Galilee, Israel) dated to 54.7 +/- 5.5 kyr BP.
There has been another paper by Wu Liu et al., (2010). (Human remains from Zhirendong, South China, and modern human emergence in East Asia, PNAS 19201–19206, doi: 10.1073/pnas.1014386107) which clearly states that: "...The Zhiren Cave human remains, securely dated to at least 100 kya (early MIS 5), therefore represent the oldest evidence of derived modern human morphology in East Asia....The age and morphology of the Zhiren Cave human remains support a modern human emergence scenario for East Asia involving dispersal with assimilation or populational continuity with gene flow. It also places the Late Pleistocene Asian emergence of modern humans in a pre-Upper Paleolithic context and raises issues concerning the long-term Late Pleistocene coexistence of late archaic and early modern humans across Eurasia."
So, how did these modern humans reach China 80 to 120 Kya? Did they leave Africa even earlier? Did they originate outside of Africa?
Apparently the old peopling wave some 130 kya proposed by Hugo Reyes-Centeno, Silvia Ghirotto, Florent Détroit, Dominique Grimaud-Hervé, Guido Barbujani, and Katerina Harvati ( Genomic and cranial phenotype data support multiple modern human dispersals from Africa and a southern route into Asia. PNAS, April 21, 2014 DOI: 10.1073/pnas.1323666111) is a fact. The South Asian route could explain an early modern H. sapiens in south China.
But there was admixing with other archaic people in Asia, the Denisovans are one of those groups, and did mix into the ancestors of Melanesians.
An early 130 kya wave of humans may have also headed north and then west, into America, reaching the New World 100,000 years earlier than what is now currently accepte...
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2015 by Austin Whittall ©
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