The Early Pleistocene human dispersals in the Circum-Mediterranean Basin and initial peopling of Europe: Single or multiple pathways?

Abstract

The issue of ancient human single or multiple dispersal pathways into Eurasia is theoretically significant for understanding adaptive processes involved in peopling vacant spaces and varied, unfamiliar ecosystems, but receives mostly marginal attention. The Western Asian staging-post remains most plausible, whereas an alternative peopling directly from the Maghreb across the Gibraltar Strait into Iberia and beyond, though problematic, is proposed repeatedly. The present review discusses these issues and findings requiring interpretation, with respect to chronology, fossil human and Palaeolithic evidence, and Early Pleistocene circumstances in the Circum-Mediterranean Basin and Europe.The spatiotemporal distribution of palaeoanthropological occurrences and Ethiopian fossil mammal expansions does not support the hypothesis of a single Early Pleistocene biogeographic event originating in Subsaharan Africa, spreading throughout Western Asia and Europe. On the other hand, this spatiotemporal distribution of ancient human evidence in Europe reveals an intriguing bimodal chronological pattern. Early Pleistocene occurrences in both Eastern Europe and Western Europe prove earlier than those in West-Central Europe and the Italian Peninsula, which are dateable to the Mid-Pleistocene.This Early Pleistocene distribution cluster of occurrences in Iberia and Atlantic Europe refutes implicitly a single linked human-Ethiopian mammal biogeographic event exclusively through Western Asia, while reviving the notion of ‘sweepstake’ dispersal directly across the Strait of Gibraltar, a scenario which, however, demands independent confirmation by reviewing past circumstances favourable for a crossing, as well as suggesting a series of multiple staging-posts. The observed bimodal spatiotemporal configuration becomes more compatible with another hypothesis namely, that Europe was peopled independently by converging population movements from both the Western Asian and Ibero-Moroccan staging posts during the Early Pleistocene, between ca. 1.85–1.40 Ma.