A research has dated more precisely the Neanderthal human remains of the cave of El Sidrón, whereas previous studies had yielded less accurate results. The application of a pre-treatment to reduce the amount of contamination by modern carbon has managed to reduce the margin of error from 40,000 years to only 3,200.
The research team of the University of Oviedo that studies the cave of El Sidrón, one of the Neanderthal archeological sites with a large amount of bone remains and stone tools, has conducted a new research that proves that the cave was inhabited 49,000 years ago. Thanks to the development of new analytical procedures, the scientists, coordinated by Professor Marco de la Rasilla, have managed to narrow down the age of these Asturian Neanderthal populations, according to the publication by the SINC agency.
The age of the remains of El Sidrón may be important information to determine when the transition from Neanderthals to Sapiens was made in Europe. "Some previous datings, which ventured an age of only 10,000 years, are abhorrent and cannot be considered viable anymore. They would be highly controversial in the discussion on when the Homo Neanderthalensis became extinct", claims Marco de la Rasilla.
In order to adjust the age of these Neanderthals, De La Rasilla and his team have compared previous results of the French Laboratory of Climate and Environmental Sciences (LSCE), with new data obtained by the Oxford Radiocarbon Accelerator Unit (ORAU). The datings offered by both laboratories permit researchers to verify that the Neanderthals of the Asturian cave lived 49,000 years ago.
Contamination "rejuvenates" the samples
"The previous dating of 10,000 for this episode was due to a contamination problem", De La Rasilla explains. The method most commonly used for dating in archeology is Carbon-14, which measures the age of the carbon present in an object. If the sample is contaminated by modern carbon, it may look younger that what it actually is.
The results of the French Laboratory of Climate and Environmental Sciences (LSCE), with new data obtained by the Oxford Radiocarbon Accelerator Unit (ORAU) confirm that Neanderthals lived 49,000 years ago
The new Carbon-14 dating in the ORAU laboratory of Oxford was preceded by a highly-sophisticated treatment of ultrafiltering used to reduce contamination as much as possible. The result revealed that the age of the remains fell between 45,200 and 51,600 years. The identification of the Neanderthal population in El Sidrón 49,000 years ago stems from the weighted average of this information and what the French lab had previously obtained by treating the samples with another pre-treatment with ninhydrin to remove any possible contamination. "The fact that two different laboratories, employing different methods, have reached similar results only reinforces this dating", De La Rasilla concludes.
Bibliography:
R. E. Wood, T. F. G. Higham, T. de Torres, N. Tisnerat-Laborde, H. Valladas, J. E. Ortiz, C. Lalueza-Fox, S. Sánchez-Moral, J. C. Cañaveras, A. Rosas, D. Santamaría, M. De La Rasilla. 2013. "A new date for the Neanderthals from El Sidrón cave (Asturias, northern Spain)". Archaeometry, 55, 1, pp.148-158. DOI: 10.1111/j.1475-4754.2012.00671.x
T. de Torres, J. E. Ortiz, R. Grün, S. Eggins, H. Valladas, N. Mercier, N. Tisnérat-Laborde, R. Julià, V. Soler, E. Martínez, S. Sánchez-Moral, J. C. Cañaveras, J. Lario, E. Badal, A. Rosas, D. Santamaría, M. de la Rasilla, J. Fortea. 2010. "Dating of the hominid (Homo Neanderthalensis) remains accumulation from El Sidrón cave (Borines, Asturias, North Spain): an example of multi-methodological approach to the dating of Upper Pleistocene sites". Archaeometry, 52, 4, pp. 680-705. DOI: 10.1111/j.1475-4754.2009.00671.x