Overview
J1-ZS851 is a downstream element of the Arabian-rooted J1-L147.1 expansion and reflects demographic processes tied to desert-steppe pastoralism in northern Arabia. Its early formation corresponds to the late Neolithic and early Bronze Age, during which communities relied on highly mobile herding strategies based on wadis, wells and seasonal migration circuits that linked the Hejaz, northern Arabia and western Mesopotamia. During the Bronze and Iron Ages, ZS851-bearing populations participated in the rise of North Arabian tribal confederations. The downstream phylogenetic structure reveals multiple founder effects related to regional clan formation in the Hejaz, Najd and the southern Levant. Some downstream branches appear in early Islamic contexts, marking participation in later tribal expansions spreading into Iraq and the Gulf region.