Prepared Core Research Articles

“Diffusion with modifications”: Nubian assemblages in the central Negev highlands of Israel and their implications for Middle Paleolithic inter-regional interactions

Nubian Levallois cores, now known from sites in eastern Africa, the Nile Valley and Arabia, have been used as a material culture marker for Upper Pleistocene dispersals of hominins out of Africa. The Levantine corridor, being the only land route connecting Africa to Eurasia, has been viewed as a possible dispersal route. We report here on lithic assemblages from the Negev highlands of Israel that contain both Levallois centripetal and Nubian-type cores. Wetter conditions over the Sahara and Negev deserts during MIS 6a–5e provided a generally continuous environmental corridor into the Levant that enabled the dispersal of hominin groups bearing the Nubian variant of prepared core technologies. The Negev assemblages draw renewed attention to the place of the Levant as one of the dispersal routes out of Africa during the Late Pleistocene and could suggest that processes of human dispersals and cultural diffusion resulted in the spread of Nubian technology across eastern Africa, the western Sahara and the Nile Valley, the southern Levant and Arabia.

Late Occupation of the High‐Elevation Northern Tibetan Plateau Based on Cosmogenic, Luminescence, and Radiocarbon Ages

10Be‐26Al cosmogenic surface exposure, optically stimulated luminescence, and radiocarbon dates from the site of Xidatan 2 (∼4300 m above sea level [asl] in the Kunlun Pass, northern Tibetan Plateau) suggest the site was intermittently and briefly occupied approximately 9200–6400 yr B.P. This age is substantially younger than expected given the late Upper Paleolithic character of the lithic assemblage, which is dominated by microlithic and unique discoidal prepared core technologies. Comparisons between Xidatan 2 and known surface lithic assemblages in the Kekexili and Chang Tang regions of the central high Plateau show not only that the latter are technologically similar to Xidatan 2, but also that they are demonstrably connected to Xidatan 2 through utilization of the same stone raw materials, which includes a chemically distinctive obsidian. Contrary to most accounts of Tibetan Plateau colonization, our results suggest that the earliest substantial occupations on the interior Tibetan Plateau above 4000 m asl may date to the Pleistocene/Holocene transition.

A comparative 3D geometric morphometric analysis of Victoria West cores: implications for the origins of Levallois technology

The ‘Victoria West’ is a Lower Paleolithic industry from South Africa, which includes prepared cores and has previously been noted to bear strong morphological resemblances with later Middle Paleolithic prepared core technologies (i.e. Levallois cores). Indeed, from the earliest commentaries on the Victoria West, it has frequently been thought of as a ‘large Levallois’ variant. The hypothesis that VW cores are accurately characterised as ‘large Levallois’ is tested here using a comparative 3D geometric morphometric (GM) methodology. GM methods are powerful statistical tools for shape analysis that offer many advantages over traditional means of shape quantification and comparison. The use of landmarks to capture shape variation allows for the preservation of the full geometry, as well as enabling the more precise description of shape versus size. Moreover, biological studies have shown that the use of landmarks allows for a flexible approach to comparing specific aspects of overall morphology. Here, we employ GM to analyse differences in core surface morphology in a range of Lower and Middle Palaeolithic artefacts, including Victoria West examples (total n = 639 artefacts). In comparison with cores from non-handaxe Mode 1, Acheulean handaxes, and Levallois cores, the Victoria West share shape affinities with both Acheulean handaxes and Levallois cores. However, when compared directly with a group of large Middle Palaeolithic Levallois cores from Baker's Hole (UK), the Victoria West were found to more closely resemble handaxes, while the Baker's Hole set are simply isometrically-scaled Levallois cores. These analyses show that, despite broad technological and qualitative morphological similarities with Levallois cores, Victoria West cores are morphologically more similar to Lower Palaeolithic artefact forms, such as handaxes, and are in some respects distinct from Middle Palaeolithic Levallois cores. In line with other recent analyses, our results support suggestions that the Victoria West technique is an extension of longstanding Acheulean traditions for the preparation of biface blanks, but with its own distinct characteristics.

Are Victoria West cores “proto-Levallois”? A phylogenetic assessment

Cores from South Africa assigned to the “Victoria West” industry have long been purported as a “proto-Levallois” core form, and thus regarded as ancestral to the Levallois prepared core technologies of the Middle Paleolithic and African Middle Stone Age. Similarities in form between Victoria West cores, in terms of surface morphology and the removal of large flakes from a prepared surface, led to hypothesized schemes of technological evolution from Victoria West cores through to fully developed Levallois cores. However, the phylogenetic basis of this Victoria West “proto-Levallois” hypothesis, and the assumptions of phylogenetic homology upon which it rests, have never been tested formally. In recent years, archaeologists have begun to use phylogenetic methods drawn from biology to test hypotheses of technological and cultural evolution. Here, the phylogenetic assumptions of the Victoria West “proto-Levallois” hypothesis are tested directly using a cladistic (maximum parsimony) protocol. The cladistic analyses indicate that Victoria West cores are not the basal sister taxon of a Levallois clade, as predicted by the proto-Levallois hypothesis. Moreover, character analyses demonstrate that several characters relating to core surfaces and flake scar morphology are not phylogenetically homologous, but result from convergent technological evolution within the Acheulean techno-complex. Post hoc analyses further determine that these results are not confounded by choice of outgroup or raw material factors. The results were also shown to be robust on the basis of the ensemble retention index statistic, bootstrap analyses, and permutation tests. Hence, it is concluded that Victoria West cores do not represent a “proto-Levallois” core form, and that the term “para-Levallois” should more correctly be applied on phylogenetic grounds. It is further argued that even in cases where different technologies are found to share phylogenetically homologous features, use of the term “proto” is questionable on theoretical grounds.

An Acheulean Factory Site with Prepared Core Technology near Taung, South Africa

An Acheulean Factory Site with Prepared Core Technology near Taung, South Africa

Raw Material Quality and Prepared Core Technologies in Northeast Asia

The design and assembly of lithic toolkits is mediated by a number of factors including the abundance and quality of raw materials available. In general, low raw material abundance and high raw material quality are thought to lead to formal tool designs, whereas high raw material abundance and low raw material quality lead to informal designs. Low raw material quality is seen as the overriding factor producing informal tool designs, even where low raw material abundance would favour formal designs. In North China, the predominance of simple flake and core technologies, based on relatively poor quality raw materials, and the near absence of sophisticated prepared core technologies seems to corroborate the importance of raw material quality in toolkit design. Recent studies of a late Pleistocene lithic assemblage from the Lower Grotto at Tsagaan Agui cave, Mongolia, suggest however that raw material quality is not an absolute constraint on the development of sophisticated core reduction strategies. Levallois-like and other prepared core forms based on large flake blanks are conspicuous in the Lower Grotto assemblage, despite the poor quality of raw material available at the site. Contrary to expectations, these core forms appear to have developed directly in response to poor raw material quality. The implication is that raw material quality alone cannot explain the apparent technological simplicity of the North Chinese Middle and Upper Paleolithic.