Detailed analysis of South Iberian Solutrean

A new study has been published that reviews all the data on the Southern Iberian Solutrean, which (excepted probably Asturias) is a distinct autonomous facies relative to Franco-Cantabrian Solutrean.

João Cascalheira & Nuno Bicho, On the Chronological Structure of the Solutrean in Southern Iberia. PLoS ONE 2015. Open access → LINK [doi:10.1371/journal.pone.0137308]

Abstract

The Solutrean techno-complex has gained particular significance over time for representing a clear demographic and techno-typological deviation from the developments occurred during the course of the Upper Paleolithic in Western Europe. Some of Solutrean’s most relevant features are the diversity and techno-typological characteristics of the lithic armatures. These have been recurrently used as pivotal elements in numerous Solutrean-related debates, including the chronological organization of the techno-complex across Iberia and Southwestern France. In Southern Iberia, patterns of presence and/or absence of specific point types in stratified sequences tend to validate the classical ordering of the techno-complex into Lower, Middle and Upper phases, although some evidence, namely radiocarbon determinations, have not always been corroborative. Here we present the first comprehensive analysis of the currently available radiocarbon data for the Solutrean in Southern Iberia. We use a Bayesian statistical approach from 13 stratified sequences to compare the duration, and the start and end moments of each classic Solutrean phase across sites. We conclude that, based on the current data, the traditional organization of the Solutrean cannot be unquestionably confirmed for Southern Iberia, calling into doubt the status of the classically-defined type-fossils as precise temporal markers.

Mallaetes, but not nearby Parpalló, is confirmed as one of the oldest sites of the Southern Iberian Solutrean, but has to share the honor with Nerja and La Boja. In general this would support the old idea of rapid expansion from Southern France (Dordogne is slightly older for this culture than the oldest Iberian sites) along the Eastern Mediterranean coast, mimicking what happened before with Aurignacian and Gravettian and what would happen later with Magdalenian and Epipaleolithic cultures of Magdalenian derivation. 

The ulterior evolution is rather fast and does not fit too well the French chronology: Middle Solutrean is short-lasting (mostly affecting Central Portugal) and almost overlaps with Upper Solutrean (oldest in Southern Portugal) and Gravetto-Solutrean (oldest in El Bajoncillo, an inland site not involved in the previous phases). 

All the new phases do impact the core site of Mallaetes, which seems to be well connected.

Fig 5. Time slices for Southern Iberia between 26 and 20 ka cal BP showing the distribution of modelled ages of the classical Solutrean phases.

The size of the dots represents increasing and decreasing levels of the 95.4% probability ranges determined from the duration (date range) of each phase, as calculated by individual Bayesian site models (see Appendix A in S1 File). Dots with two colors indicate overlapping date range probabilities for two or more phases found at the same site.

The authors underline that:

Two clear tendencies can be outlined related to the distribution patterns of the Lower Solutrean and Solutreo-Gravettian type assemblages. In fact, these two components seem to be restricted to the Mediterranean region and totally absent from the Atlantic facade.

They conclude that:

... the main impacts of our analysis on the current knowledge of the LGM adaptations in Southern Iberia can be summarized as follow:

1. The call into doubt of the status of the traditionally-defined type-fossils as precise temporal markers for each Solutrean phase in Southern Iberia;
2. The confirmation of the presence of tanged “Parpalló-type” points at a much earlier time (c. 25 ka cal BP) than previously thought;
3. The potential contemporaneity at a very early moment (c. 25 ka cal BP) of the so-called Middle and Upper Solutrean/Solutreo-Gravettian phases (and thus should preferably be called facies)
4. The likely organization, from a broad chrono-cultural point of view, of the adaptive systems surrounding the LGM event in just two discrete contiguous entities, known as the Proto-Solutrean and the Solutrean.

Some further context (my elaboration)

The Iberian Solutrean (roughly coincident with the Last Glacial Maximum) was the most populous period of the Upper Paleolithic in that province, at least according to the research of Bocquet-Appel. 

It was maybe even more important for North Africa (Iberomaurusian culture), something not discussed in this study but that I am conscious interests many readers, as well as myself. For this reason I checked for a good reference on oldest calibrated dates for Taforalt's Iberomaurusian (alias Oranian) and found this 2013 study that states that it is as old as at least 21,160 Cal BP. 

That would correspond with the fifth map (22-21 Ka cal BP), in which we see an increase of the closest site to North Africa: Gorham's Cave. It would be indeed interesting if someone compared the specifics of Upper Solutrean and that cave with Taforalt, which is by all accounts the oldest Iberomaurusian site. 

The Iberomaurusian genesis, the first known Upper Paleolithic of NW Africa, surely carried a still very apparent Iberian-like genetic signature to across the strait, notably mtDNA haplogroups H1, H3, H4 and H7, and also maybe V. The H subclades were claimed to have an unmistakable Iberian origin by Cherni 2008, while the distribution of the H subhaplogroups in the region was researched by Enafaa & Cabrera 2009. Comparison with Álvarez-Iglesias 2009 suggests that H7 should rather be French than Iberian by origin however, as it is rare in the peninsula. It could still be a Solutrean founder effect anyhow. 

Another possible founder effect of this Paleolithic trans-Mediterranean connection might be mtDNA U6. This lineage has a most likely origin in Northern Morocco but also has a lot of basal diversity across the strait in Iberia. However it could also represent a, so far archaeologically invisible, Aurignacoid migration via NE Africa with re-expansion to Iberia (and also in North Africa) in this period maybe. This could also explain its apparent connection with Y-DNA E1b-M81, which seems very old in NW Africa and is distributed in a similar way to U6 in the Iberian Peninsula and Europe in general.