Initial Upper Palaeolithic of the Iranian Plateau; Sorheh Rockshelter: A techno-typological perspective

The Iranian Plateau is a vast geological feature that connects western Asia (including the Caucasus) to the south (India) and east (including Central Asia). This Plateau consists of different biogeographical units, making it attractive to a high variety of fauna, flora and hominin taxa. This geographic location puts the Iranian Plateau at the centre of important evolutionary changes during the late Pleistocene. Sporadic Palaeolithic research in Iran confirms its high potential in answering important questions regarding late Pleistocene hominins and the diversity of culture. One of these questions is the transition from Middle to Upper Palaeolithic and the generation of new lithic techno-complexes and cultural units. The newly discovered site of Sorheh Rockshelter, located on the southern piedmonts of the Alborz Mountains at the northern Iranian Plateau, revealed a novel behavioural trait known as the Initial Upper Palaeolithic techno-complex. Sorheh Rockshelter, located at a high elevation of 1903 m asl., is one in a complex of 6 caves and rockshelters in the region. During two seasons of excavation in 2019 and 2022, numerous lithics and fauna have been recovered, indicating a single cultural occupation in a long chronological frame of ~50–35 ka cal. BP. Despite Sorheh Initial Upper Palaeolithic shares techno-typological features with known counterparts in the Levant, Eastern Europe and East Asia, it reveals strong local characteristics. These characteristics indicate diversity of hominin behaviours during the late Pleistocene. The temporal window exposed in Sorheh suggests that the Initial Upper Palaeolithic occupation in this site lasted a long time, hypothesising this part of the Iranian Plateau as a potential core area for this techno-complex. Meanwhile, regardless of this hypothesis, Sorheh fills the gap in the diffusion of the Initial Upper Palaeolithic towards Central and East Asia, uncovers the important role of this plateau in the cultural evolution of our lineage and its expansion.