Assignment
of fossil teeth from Fuyan Cave to Homo sapiens is ‘unequivocal’
Ever since genetic evidence
emerged to support the ‘recent Out of Africa’ model of modern human origins,
the orthodox view is that until around 60,000 years ago modern humans were
confined to Africa and a short range extension into Southwest Asia. The latter
is thought to have been brought to an end as colder, more arid climatic
conditions set in around 90,000 years ago. The model has been challenged by
archaeological evidence suggesting that modern humans were established on the
Arabian Peninsula 125,000 years ago and had reached India 77,000 years ago.
What has up until now been
lacking is unequivocal fossil evidence significantly earlier than around 45,000
years old. Controversial evidence had previously been reported from two sites
in southern China. An age of up to 139,000 years old has been claimed for the
Liujiang Skull, discovered in 1958, but the exact geological position of the
find was not documented and the skull could actually be as little as 30,000
years old. A lower jawbone and two molar teeth from Zhirendong (‘Homo sapiens cave’) in Guizhou Province
have been securely dated to 106,000 years old, but it is not certain that these
remains belonged to a modern human.
However, the discovery has now
been reported of 47 teeth at the newly-excavated site of Fuyan Cave in Daoxian,
Hunan Province. Uranium series dating of associated stalagmite fragments gave a
minimum age of 80,000 years old for the teeth and faunal dating gave a maximum
age of 120,000 years old. The teeth were compared with those of Late
Pleistocene humans from Europe, Asia and Africa and were found to fall
consistently within the Homo sapiens size
range. They are generally smaller than other Late Pleistocene samples from Asia
and Africa, and are closer to European Late Pleistocene samples and the teeth
of present-day people. They resemble the latter far more closely than they do
the teeth of Neanderthals or Homo erectus.
The announcement adds a
radical new dimension to the history of modern human dispersals in Eurasia.
Reference:
Liu, W. et al., The earliest unequivocally modern
humans in southern China. Nature 526, 696-699 (2015).
No comments:
Post a Comment