Body proportions in Late Pleistocene Europe and modern human origins

Body proportions covary with climate, apparently as the result of climatic selection. Ontogenetic research and migrant studies have demonstrated that body proportions are largely genetically controlled and are under low selective rates; thus studies of body form can provide evidence for evolutionarily short-term dispersals and/or gene flow. Following these observations, competing models of modern human origins yield different predictions concerning body proportion shifts in Late Pleistocene Europe. Replacement predicts that the earliest modern Europeans will possess “tropical” body proportions (assuming Africa is the center of origin), while Regional Continuity permits only minor shifts in body shape, due to climatic change and/or improved cultural buffering. This study tests these predictions via analyses of osteometric data reflective of trunk height and breadth, limb proportions and relative body mass for samples of Early Upper Paleolithic (EUP), Late Upper Paleolithic (LUP) and Mesolithic (MES) humans and 13 recent African and European populations. Results reveal a clear tendency for the EUP sample to cluster with recent Africans, while LUP and MES samples cluster with recent Europeans. These results refute the hypothesis of local continuity in Europe, and are consistent with an interpretation of elevated gene flow (and population dispersal?) from Africa, followed by subsequent climatic adaptation to colder conditions. These data do not, however, preclude the possibility of some (albeit small) contribution of genes from Neandertals to succeeding populations, as is postulated in Bräuer’s “Afro-European Sapiens” model.