Friday, 20 July 2012

Redating of the Early Upper Paleolithic site of Riparo Mochi (Italy)

There are two possibilities on how the early Aurignacian entered Europe. According to one hypothesis, its bearers followed the Danube, which formed a natural corridor into the heartland of the continent which was, at the time, thickly forested. A different hypothesis is that the early Aurignacian entered Europe via the Mediterranean. Distinguishing between the two hypotheses depends on obtaining reliable chronological estimates for the Mediterranean and Central European Aurignacian

A recent dating of a site in the Swabian Jura suggested that the Aurignacian was earlier attested in Central Europe. But, another paper in the Journal of Human Evolution examines meticulously the sequence in the Moch rockshelter and finds that it is just as early.
Comparisons with dates for other Upper Palaeolithic contexts outside Italy suggest that the date of the Protoaurignacian of Mochi compares closely. In Fig. 9a the start boundaries for the earliest Aurignacian evidence at the sites of Geissenklösterle (Germany), Abri Pataud and Isturitz (France) are compared to the start boundary for unit G in Mochi. The first two sites were dated recently in Oxford with reliable methodologies (Higham et al., 2011; Higham et al., in press) while for Isturitz only a small number of dates exist for the earliest Upper Palaeolithic (Szmidt et al., 2010). This comparison reveals that the lowermost Aurignacian levels at Geissenklosterle (AHIII) and Isturitz (C4d) date to the same period as Mochi G, at around 42.7-41.5 ka cal BP (68.2%). The earliest Aurignacian of Abri Pataud dates slightly later to around 41e40 ka cal BP (68.2%), but the assemblage there has always been considered more evolved, so this is not surprising. No Mousterian dates are included in any of these calculations, therefore the start boundaries in the Bayesian models are not well constrained at their earliest end. What is interesting is that there appears to be a close similarity between the dates for the Protoaurignacian and Early Aurignacian sites in Germany on the Danube and on the Mediterranean coast. This might suggest a rapid dispersal of both variants of the Aurignacian across Europe at c. 44-42 ka cal BP.
It does appear that the Aurignacian was a continent-wide punctuational event in Europe which occurred in the middle to late 40 thousands ka cal BP.

Either there were two streams into Europe (Danubian and Mediterranean), or one stream that quickly inundated much of the continent. Given that the argument for the Danubian Corridor is partly related to the ease of access it provided, it is difficult to imagine how the people who followed it would quickly stray far from it all the way to Italy. Overall, it does appear that there were multiple streams into Europe, and perhaps new research in the Balkans, Eastern Europe, and West Asia, may help us trace the earlier predecssor of these streams before they followed their separate ways into Europe.

Journal of Human Evolution DOI:10.1016/j.jhevol.2011.11.009

A new chronostratigraphic framework for the Upper Palaeolithic of Riparo Mochi (Italy)

Katerina Douka et al.

The rockshelter of Mochi, on the Ligurian coast of Italy, is often used as a reference point in the formation of hypotheses concerning the arrival of the Aurigancian in Mediterranean Europe. Yet, the site is poorly known. Here, we describe the stratigraphic sequence based on new field observations and present 15 radiocarbon determinations from the Middle Palaeolithic (late Mousterian) and Early Upper Palaeolithic (Aurignacian and Gravettian) levels. The majority of dates were produced on humanly modified material, specifically marine shell beads, which comprise some of the oldest directly-dated personal ornaments in Europe. The radiocarbon results are incorporated into a Bayesian statistical model to build a new chronological framework for this key Palaeolithic site. A tentative correlation of the stratigraphy to palaeoclimatic records is also attempted.