A late Middle Pleistocene Middle Stone Age sequence identified at Wadi Lazalim in southern Tunisia

Abstract

The late Middle Pleistocene, starting at around 300 ka, witnessed large-scale biological and cultural dynamics in hominin evolution across Africa including the onset of the Middle Stone Age that is closely associated with the evolution of our species-Homo sapiens. However, archaeological and geochronological data of its earliest appearance are scarce. Here we report on the late Middle Pleistocene sequence of Wadi Lazalim, in the Sahara of Southern Tunisia, which has yielded evidence for human occupations bracketed between ca. 300-130 ka. Wadi Lazalim contributes valuable information on the spread of early MSA technocomplexes across North Africa, that likely were an expression of large-scale diffusion processes.

Figure 1

Geographic and stratigraphic setting of the MSA sites at Wadi Lazalim (maps created using QGIS 3.20.2 https://qgis.org/it/site/). a: localization and main geographic features of the research area (base maps: left, made with Natural Earth; right, made with SRTM 1 ArcSec); b: satellite view of the area encompassing the excavated sites (Google Earth); c: view of Wadi Lazalim from the heights north of site 16/15 looking eastwards; d: drawing of the excavated stratigraphic sections at Site 16/29 (South profile), Site 16/15 (South profile) and Site 15/1 (East profile) with indication of results from the IRSL dating (description of the sedimentary units in Supplementary Information); numbers and letters to the left of each section indicate layer names.

Figure 2

Archaeological materials discussed in the text. a, Site 16/15: 1, Levallois core (Layer I); 2, Levallois flake (Layer J); 3, convergent scraper (Layer I); 4–5, bifacial knives (layer H); 6, core-axe (layer H). b, Site 15/1: 7, blade core (Layer 7); 8, Levallois point core (layer 4a); 9, Levallois point (layer 4b); 10, side-scraper (Layer 4b); 11, end-scraper (Layer 5); 12, tanged tool (layer 5); 13, backed piece (layer 4b); 14, backed piece (layer 4a). c, Site 16/29: 15, notch on a Levallois flake (Layer 6); 16, discoid flake (Layer 6); 17–18, flakes from bifacial reduction (Layer 3 and 4 respectively); 19, tanged tool (layer 7); 20, beck (Layer 4); 21, point (outside excavated trench, same sedimentary sequence).

Figure 3

Map of Middle Pleistocene MSA contexts with chronometric estimates in North Africa (WL stands for Wadi Lazalim, the sites here discussed): 1, Bizmoune; 2, Jebel Irhoud; 3, Benzù; 4, Ifri n’Ammar; 5, Haua Fteah; 6, Taramsa 1; 7, Kharga; 8, Dakhla; 9, Bir Tarfawi; 10, Bir Sahara; 11, Sai 8-B-11; 12, EDAR 135; 13, Al Jamrab. Marine Isotopic Stage (MIS) of earliest estimated occupation is also indicated for each site (map created using QGIS 3.20.2 https://qgis.org/it/site/; base map made with Natural Earth).