Spatial ecological gradients and non-equilibrium niche construction dynamics in the Levantine Middle-Upper Palaeolithic transition

Abstract

This article revisits the Middle-Upper Palaeolithic (MP-UP) transition in the Levant (ca. 50–40 kiloanni calibrated before present, hereafter ka), explored here as a key case of spatially and temporally multiscalar niche construction and biocultural adaptation in recent human evolution. New chronometric and palaeogenomic data provide an opportunity to reconsider what actually changed in the MP-UP transition, not only in terms of Neanderthal-anatomically modern human (AMH) population turnover and biological adaptation, but also culturally transmitted technologies and cultural institutions that mediated interrelated changes in mobility and social-network connectivity. High-resolution satellite data on environmental variability, simulation studies of hunter-gatherer demographic fluctuations, and cross-cultural data on hunter-gatherer population density and social organization are evaluated to model baseline constraints and possibilities for long-term biocultural adaptation and niche construction in the region, across the Middle and Late Pleistocene more broadly (ca. 780–12 ka). This exploration adds theoretical support to a view of the MP-UP transition as evolutionary, rather than revolutionary, offering new avenues of inquiry about how shorter-term, local behavioural responses were affected by and—in turn—had ripple effects on geographically more widespread, longer-term trends involving intergenerational demographic dynamics, centennial or millennial-scale population turnovers, and major long-term technological shifts.