ABSTRACT P.I. Erik Trinkaus SBR- 9321339 The question of modern human origins remains the center of active debate. There are currently two opposing models for our emergence. The first, "Replacement," posits that modern humans arose first in a restricted region (most likely within sub-Saharan Africa) in the late Middle or early Late Pleistocene, and subsequently spread out of Africa, replacing existing archaic human populations elsewhere in the world. This model would deny the Neandertals significant (if any) genetic contribution to modern Eurasian populations. The second model, "Regional Continuity," proposes that gene flow among archaic human populations was sufficient to prevent speciation, with modern humans evolving gradually from a single diverse archaic human stock distributed throughout the Old World. This model identifies presumed regional features that persist across the archaic/modern human boundary, and the model affords the Neandertals full status as ancestors of modern Eurasians. Fossil evidence suggests late archaic sub-Saharan Africans were characterized by a tropically-adapted morphology, akin to moderns there. If the replacement model is correct, the first modern humans in cold-temperate regions should be characterized by these same features, different from those of European archaics, for example. The regional continuity model would argue that the ecogeographic patterning in body size and proportions found today dates back to the Middle Pleistocene spread of hominids to mid-latitudes. Through an examination of fossil post-cranial remains, the investigators will test these t wo hypotheses on changing body proportions over the last 50,000 years of human evolution. It also will result in the training of an excellent new professional. *** Panthrojfried9321339.abs ! ! ! D 6 6 ( Times New Roman Symbol & Arial ? ? ? " h es Eis E R | = Jonathan Friedlaender Jonathan Friedlaender
