Among Arabian sands: Defining the Palaeolithic of southern Arabia

Until present, the Palaeolithic period in southern Arabia has been more or less terra incognita. Within the last decade, evolutionary scientists have begun to recognize the key role this region must have played in the origin of modern humans. Recent discoveries in the field of genetics underscore the significance of the Peninsula as a conduit for early human migration to and from Africa.; The hypothesis proposed in this dissertation---the Arabian Corridor Migration Model---synthesizes these new genetic data with the Arabian palaeoenvironmental record. It is proposed that one or more hunter-gatherer groups expanded into southern Arabia in the late Middle and/or Upper Pleistocene (400--20 kya) from East Africa, during phases when favorable climatic conditions transformed the arid interior into an ameliorated savanna. These wet periods may have caused a genetic bottleneck release that fueled demographic movements throughout the tropical belt (e.g., East Africa and the Indian subcontinent), as well as the Levant. Conversely, dry periods would have triggered large-scale desiccation throughout the Arabian Peninsula and wiped out pre-existing hominid populations---called tabula rasa events. Because of these tabula rasa events, the possibility of autochthonous development throughout the Pleistocene of Arabia can be discounted, thereby avoiding Galton's Problem of migration versus diffusion.; The Arabian Corridor Migration Model is tested using archaeological data collected during the Central Oman Pleistocene Research (COPR) 2002 and 2004 fieldwork campaigns. Based on these data recovered by COPR, three new lithic industries, sensu latu, are described: the Sibakhan, the Nejd Leptolithic, and the Khasfian. While the latter two are dominated by a core reduction strategy that primarily produced blades, the Khasfian is almost exclusively characterized by the faconnage manufacture of bifacial foliates. Placing these industries within a broad regional context, their techno-typological elements suggest affinities with all three surrounding refugia (i.e. Levant, East Africa, and India) at different times, and support the model of modern human expansion into Arabia during the Upper Pleistocene. The directionality of this expansion remains questionable, however, and two possibilities seem equally plausible based on the archaeological evidence: an eastward movement from East Africa into Arabia, and/or a westward dispersal from the Indian subcontinent.