How Long was the Mesolithic–Neolithic Overlap in Western Scotland? Evidence from the 4th Millennium <scp>bc</scp> on the Isle of Islay and the Evaluation of Three Scenarios for Mesolithic–Neolithic Interaction

Ancient DNA studies have identified western Scotland as the only known region in Britain where inter-breeding occurred between early 4th millennium bc Neolithic migrants and indigenous Mesolithic population. By drawing on excavations at sites Isle of Islay, I identify a period population overlap suggest three scenarios for Mesolithic–Neolithic interaction: swift succession, dual population, biocultural merger. These are evaluated against archaeological evidence from Islay elsewhere Scotland, with reference to patterns interaction continental Europe. A cautious preference is expressed merger, occurring mid-4th mid-3rd millennia , that could be termed ‘Neomesolithic’.