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

Abstract

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.

Introduction

Nubian Levallois technology was initially suggested to represent a technological component found within different local lithic industries confined geographically to the Nile Valley and Nubia (Guichard and Guichard, 1965, Marks, 1968a, Van Peer, 1992). These industries were later integrated into a single techno-complex defined as the Nubian Complex (Van Peer, 1998, Van Peer, 2001, Van Peer and Vermeersch, 2000). In Africa discoveries of Nubian cores have been reported from Kenya (Tryon et al., 2012), Ethiopia (e.g., Wendorf and Schild, 1974, Kurashina, 1978), and the Libyan Desert (Foley et al., 2013). The discovery of Nubian cores in surface collected assemblages from Arabia (See Table 1 for a list of assemblages with Nubian cores and Fig. 1 for a map of with their location) led to the revival of the discussion as to their cultural significance (Rose et al., 2011, Crassard and Hilbert, 2013, Usik et al., 2013), using Nubian Levallois technology as a “type fossil” for the dispersal of Homo sapiens out of Africa and into Arabia (Van Peer and Vermeersch, 2007, Usik et al., 2013) or vice versa (Rose et al., 2011, Marks and Rose, 2014). Dated sites with a Nubian component are few (Table 2), including only one dated occurrence in Arabia with Nubian technology – Aybut Al Auwal in Oman dated to a minimum of ∼107 ka (Rose et al., 2011). Other sites in Arabia were assigned to MIS 5 based on paleoclimatic inferences (Crassard et al., 2013, Usik et al., 2013). The same is true for the Nile Valley Nubian assemblages. Excluding Taramsa 1 and Sodmein cave, dated to 68–78 ka and 118 ka respectively, all other sites were assigned a chronological framework based on geographical and paleoclimatic considerations (Mercier et al., 1999, Van Peer, 1998, Vermeersch and Van Peer, 2002, Chiotti et al., 2009, Van Peer et al., 2010: 224, 229; Scerri et al., 2014a).

To date, only sporadic occurrences of Nubian cores have been recorded from Levantine Middle Paleolithic (MP) assemblages (Munday, 1976a, Vermeersch, 2001). The finding of Nubian core technology in the previously unpublished H2 surface collection (N = 686) from the Negev highlands (Fig. 1), and the recognition of Nubian cores in other published MP surface collections from Har Oded (HO) and North Mitzpe Ramon (NMR), situated in the same area (Boutié and Rosen, 1989), rekindles interest in the southern Levant within the context of discussing Late Pleistocene modern human dispersals across vast geographical areas (i.e. northeastern Africa, eastern Africa, the Nile Valley and adjacent deserts, the Levant and Arabia). In addition, several researchers have proposed that the Nubian technology should be viewed as an antecedent for the transitional industry at Boker Tachtit Level 1 (Van Peer, 2004, Belfer-Cohen and Goring-Morris, 2007, Belfer-Cohen and Goring-Morris, 2009, Van Peer et al., 2010: 241–242; Rose and Marks, 2014). In this context, finding Nubian technology in MP assemblages from the central Negev highlands may suggest the presence of a local antecedent for the Boker Tachtit assemblages.

Three common explanations are used to explain the existence of technological similarities in assemblage compositions across the landscape: convergence, dispersal and diffusion (Will et al., 2015, Groucutt et al., 2015). As lithic assemblages are comprised of one or multiple technological traits, identifying the permutations of distinct technological trait sets within assemblages may assist in recognizing past human interactions, diffusion of knowledge and possibly dispersals.

Adapting to a changing environment propagates the search for technological solutions, and such factors may therefore result in convergence, manifesting the same set of solutions even if they emerge from different, unrelated conditions (Shennan, 2000). Convergence has also been suggested for the existence of technological similarities across geographical and temporal discontinuities (Wang et al., 2012, Adler et al., 2014, Will et al., 2015). Another explanation ties convergence to small effective population sizes, geographically restricted social networks, or high extinction rates (Hopkinson et al., 2013).

The term “dispersal” refers to the movement of groups across the landscape with no preferred direction, in search for resources. The term “demic diffusion” in the sense of Ammerman and Cavalli-Sforza (1984) is used to describe the spread of populations and their associated cultural behaviors, in this case lithic technology, into and across areas previously uninhabited by the dispersing groups. Should this area be inhabited by other groups, the process of demic diffusion can lead to displacement, replacement or intermixing with a pre-existing population. Demic diffusions were suggested as the cause of changes in material culture during the European colonization by modern humans and the appearance of agriculture during the Neolithic (Ammerman and Cavalli-Sforza, 1984, Fort, 2012). Finally, “cultural diffusion” consists of the transfer of ideas and knowledge. This process of transmission can occur along several trajectories, the two main ones being “vertical” transmission, which occurs within the social group usually from parent to offspring, and “horizontal” transmission, often originating from outside the social group (Guglielmino et al., 1995, Shennan, 2000). While vertical transmission adds to the stability of cultural traits along time (Guglielmino et al., 1995), horizontal transmission is the main driver of the diffusion of innovations and new technologies (Shennan, 2000, Henrich, 2001, Fort, 2012). In the context of this article, we refer to situations where dispersals of human groups do not result in the total replacement of one culture by another as “diffusion with modifications”. In such cases, dispersals result in cultural diffusion of technological traits and ideas which are then integrated into the locally-used technology.

A special variant of the Levallois “tortoise” cores in the Egyptian Nile Valley was first described by Seligman (1921), although the name Nubian was given to these cores by Guichard and Guichard (1965) who defined two types of Nubian cores. These initial definitions have since been refined and expanded by many researchers, at times widening it by adding intermediate types (Chiotti et al., 2009, Crassard and Thiébaut, 2011, Rose et al., 2011, Usik et al., 2013). Although the terminology that defines the Nubian core technology alludes to shape (i.e., typology), it encapsulates a number of technological processes that must be carried out to obtain the shape, which distinguishes it from other Levallois reduction sequences. For the Nubian technology to be used as a marker for hominin movements, its definition must rest on a set of technological criteria that can be associated with a repeatedly-occurring set of technological traits, referred to here as a “lithic technological package”. In the case of the Nubian cores, current evidence suggests that their geographic distribution does not extend into the northern Levant or Europe, which indicates that their presence is not merely a by-product of Levallois production (see below). Thus when repeatedly associated with a technological package, even low frequencies of Nubian cores may justify their use as markers for hominin movements and interactions.

This paper discusses the technological characteristics of Nubian flaking technology at site H2 and other Negev highland sites in the southern Levant. From this specific case study we go on to argue that the existence of extensive technological variability amongst MP populations in the southern Levant during MIS 5 may be linked to events of population dispersals, as predicted by the range expansion model of modern human dispersals along ecological corridors (Lahr and Foley, 1994, Lahr and Foley, 1998, Foley and Lahr, 1997, Foley et al., 2013). We then discuss the relevance of Nubian technology as a means to track hominin dispersals and technological diffusion through inter-group contacts.