Assessing Earliest Human Settlement of Eurasia: Late Pliocene Dispersions from Africa
Turner, Alan, Antiquity
The timetable of human dispersions remains a matter of major interest, whether the focus of attention centres on earliest colonization of Europe or on the wider pattern of appearance in Eurasia (Turner 1992; Huang et al. 1995; Wood & Turner 1995; Beardsley 1996; Larick & Ciochon 1996). The question of earliest European occupation remains a particularly vexed one, with exchanges of opinion over so-called long and short chronologies continuing to appear with some frequency in recent years (Bonifay & Vandermeersch 1991; Roebroeks & van Kolfschoten 1994; 1995a; 1995b; Carbonell et al. 1995; Dennell & Roebroeks 1996; Roebroeks & van Kolfschoten 1998).
While the archaeological and skeletal evidence considered in a clearly established chronological framework must remain the primary basis for discussion, it is equally apparent that the larger context of human dispersion deserves consideration. Dennell & Roebroeks (1996: 539) acknowledge this point in one of the most useful recent discussions of the problem of early dispersions but do so really only in passing. As they emphasize, all of the opposing views on European settlement accept that any human occupation prior to perhaps 500,000 years is likely to have been less intensive and more intermittent. I have previously suggested that this pattern may have largely resulted from changes in the structure and composition of the large carnivore guild as a determinant of resource availability (Turner 1992). Whatever the accuracy of that argument, it is evident that human dispersions are only one facet of the evolution of the terrestrial mammal fauna of the Plio-Pleistocene (Azzaroli et a]. 1988; Turner 1995a; Turner & Wood 1993a; 1993b). Moreover, the earliest agreed traces of human presence in Eurasia, currently somewhere around the 1.5-million-year point (Roebroeks & van Kolfschoten 1998), are unlikely to record the earliest appearance of humans outside Africa; we must consider at least the past 2 million years as a possible time frame. The discussion of earliest human movements should therefore take place in the wider setting of latest Pliocene and Pleistocene evidence for actual and potential biotic contact and movement between Africa and Eurasia, based on an understanding of mammalian palaeontology, plate tectonics, palaeoclimatic reconstruction and evolutionary theory as it applies to the origin and subsequent history of species. We may then approach the matter of human dispersion by posing a series of questions, as done by Dennell & Roebroeks (1996: 540) but with a slightly larger perspective. Thus we may ask what hominin(2) species are we dealing with and what were their technological capabilities? What is the likely timetable of movements and what were the constraints and obstacles operating at various time? When were other taxa moving? Are there identifiable periods when dispersion is unlikely to have been possible? How likely is human emigration from Africa around or even prior to the Pliocene-Pleistocene boundary as required by any longer chronology for European occupation, however intermittent it may initially have been?
Earliest occurrences and dispersions of the genus Homo
Humans have reached their present distribution through a process of dispersion that originated some two to three million years ago in Africa, but the number and timing of extra~African dispersion events has long been unclear and contentious (Bordes & Thibault 1977; Dennell 1983; Turner 1984; Bonifay & Van dermeers ch 1991; Roebroeks & van Kolfschoten 1995a). Some of the recent claims for an early appearance outside Africa now suggest that a Late Pliocene - Earliest Pleistocene movement be seriously considered (Swisher et al. 1994; Vekua & Gabunia 1992; Gabunia & Vekua 1995; Huang et al. 1995).
Under the Recognition Concept of species, new taxa originate in allopatry and remain within their preferred habitats until fresh conditions provoke a fresh pattern of range fragmentation (Turner & Paterson 1991). …