Overview
J1-ZS1558 is a downstream member of the Arabian-rooted J1-L147.1 cluster and originated among early pastoralist groups inhabiting northern Arabia during the late Neolithic and early Bronze Age. These communities depended on desert-steppe ecological systems built around wells, ephemeral streams and rotational grazing cycles, forming mobility pathways that later became the demographic backbone of early North Arabian tribal formation. Throughout the Bronze and Iron Age periods, ZS1558-bearing populations were active participants in regional tribal expansions stretching across the Hejaz, Najd and western Mesopotamia. Distinct founder effects in its downstream structure indicate stable clan-based population growth. Early Islamic expansions further spread several derivative branches into Iraq and the Gulf region, where additional microclades subsequently developed.