A Bayesian luminescence chronology for the Bawa Yawan Rock Shelter at the Central Zagros Mountains (Western Iran)

Abstract

Bawa Yawan Rock Shelter is one of the critical Palaeolithic sites discovered recently in the Central Zagros in Western Iran. The site exhibits a rich assemblage from the Middle Palaeolithic (Zagros Mousterian) to the Epipalaeolithic, and it discloses one Neanderthal canine tooth. The site stands out as one of the handfuls of Palaeolithic sites in the Central Zagros that contain human remains. Therefore, establishing a reliable chronology revealing the temporal period in which Neanderthals inhabited the region plays a significant role in our understanding of the human past in the region. We employed luminescence dating in combination with Bayesian modelling to improve the precision of the estimated ages. Our results indicate that the Middle Palaeolithic assemblages unearthed from geological layers GH3 to GH5 in the site fall in the [58–80] ka time frame (68% credible interval). More importantly, the Bayesian age for the layer containing the Neanderthal remains exhibited [65–71] ka (68%). This age contradicts the previous 14C-based chronology. We argue that it is likely that the 14C dates underestimate the timing of the Middle Palaeolithic industries at Bawa Yawan.Furthermore, our study reveals the first luminescence age for the Epipalaeolithic in the Central Zagros, which is dated to [13–15] ka (68%).