Early desert settlement needed both water and stone

Researchers surveyed palaeolakes and archaeological landscapes in Arabia's Rub' al Khali, then modelled why Middle Palaeolithic and Middle Stone Age groups avoided the central basin even during wet periods. Despite abundant former freshwater lakes and more than 95% ground visibility, they found no stone-tool record indicating sustained occupation there. A spatial model validated against 301 sites in adjacent Oman and expanded across 363 documented Arabian sites showed that activity concentrated where water and knappable stone occurred together. Groups dispersed between these dual-resource islands and stalled when the gaps grew too large. The finding reframes early migration from simply following green corridors to balancing drinking water with raw material for technology. Archaeological absence cannot prove nobody ever visited, and preservation, survey intensity and dating resolution still limit the model.