Beyond arrows on a map: The dynamics of Homo sapiens dispersal and occupation of Arabia during Marine Isotope Stage 5

Arabia occupies a crucial central position between Africa and Eurasia. The northward expansion of the monsoonal rain-belt and the formation of grasslands during Marine Isotope Stage (MIS) 5 provided favourable conditions for Homo sapiens to occupy and traverse now arid areas of Arabia. While "Green Arabia" may have been a crucial stepping-stone on the way to H. sapiens global settlement, the occupation of Arabia is an important area of study in itself and could offer vital perspectives on human-environment interactions. In particular, Green Arabia can offer a unique insight into processes of human dispersal, occupation and extirpation in an environmentally fluctuating landscape. Here we synthesise archaeological, palaeoclimate and ethnographic data to develop a holistic model for the occupation of Green Arabia and offer targets for future research. We suggest that, on broad timescales, the resource availability and carrying capacity of Green Arabia facilitated rapid population expansion and occupation across Arabia. On human time-scales, dispersal was probably a slow process due to the requirements of metapopulation structures, likely consisting of many "micro-dispersals" spanning numerous generations. Transitions to more arid conditions were probably echoed by local hominin extirpations, dispersals into surrounding regions and retraction to resource-retaining core areas.