Radiocarbon dating & Bayesian modelling from the Grotte du Renne & a Neanderthal origin for the Châtelperronian

Hublin et al (2012) have published a new series of AMS determinations from the site of the Grotte du Renne at Arcy-sur-Cure, one of the key sites in discussions regarding late Neanderthal behavior and adaptation. The site is well known as one of the very few Châtelperronian sites that appear to contain evidence for the range of ornaments and objects that are usually found in sites of the Proto- or Early Aurignacian in Europe, and therefore associated with anatomically modern humans. For this reason it is important that we have an idea of the chronology of the sequence here, so that we may compare it with other contexts where similar cultural horizons have been excavated.Higham et al (2010) published a series of 31 AMS dates from well-selected humanly-modified material from several layers of the site. They found variation in the results that they ascribed to taphonomic influences, which implied strongly that there was some degree of mixing of material within the site. They recommended that caution was therefore required in literally interpreting the archaeological evidence, especially the relationship between human remains and ornaments from the Châtelperronian levels. Caron et al (2011) and Zilhão et al (2011) criticised this, citing a range of archaeological and stratigraphic evidence which suggested the opposite; that the sequence remained largely intact save for some obvious examples where the excavators had identified some material from a different layer. Hublin et al\u27s (2012) new results have been taken to suggest that: a) the original Oxford series of determinations are largely variable due to low collagen preservation which exacerbates the contamination effect in the dated bones; b) that the selection of humanly-modified material resulted in a biased corpus of poorly preserved samples for dating; c) that the new determinations show no evidence for mixing in the site because the results are consistent with the stratigraphic divisions at the site. In this short paper we comment on these suggestions