Modern Human Ancestry at the Peripheries: A Test of the Replacement Theory

Abstract

The replacement theory of modern human origins stipulates that populations outside of Africa were replaced by a new African species of modern humans. Here we test the replacement theory in two peripheral areas far from Africa by examining the ancestry of early modern Australians and Central Europeans. Analysis of pairwise differences was used to determine if dual ancestry in local archaic populations and earlier modern populations from the Levant and/or Africa could be rejected. The data imply that both have a dual ancestry. The diversity of recent humans cannot result exclusively from a single Late Pleistocene dispersal.

On the reliability of recent tests of the Out of Africa hypothesis for modern human origins

“…We also show that there are significant problems with the character state datasets employed in the studies. Lastly, we highlight evidence that the main method used in the studies (pairwise difference analysis) is not reliable when applied to the type of data employed by Hawks et al (2000) and Wolpoff et al (2001). In view of the foregoing, we contend that Hawks et al 's (2000) and Wolpoff et al's (2001) claim to have disproved the Out of Africa hypothesis cannot be sustained.…”

“…In this paper we critique two recent studies that have been claimed to disprove the Out of Africa hypothesis for modern human origins (Hawks et al, 2000;Wolpoff et al, 2001). We show that the test prediction employed by Hawks et al (2000) and Wolpff et al (2001) is not relevant to many versions of the Out of Africa hypothesis, and that the key specimens they used are problematic in terms of morphological representativeness.…”

“…Here we argue that recent claims that the Out of Africa hypothesis for modern human origins (also called the Recent African Origin hypothesis, African Replacement hypothesis, or simply the Replacement hypothesis) has been disproved (Hawks et al, 2000;Wolpoff et al, 2001) are invalid because the foregoing conditions were not satisfied. The prediction tested by Hawks et al (2000) and Wolpoff et al (2001) is incorrectly formulated, the data they employ are flawed, and there are substantial problems with the main method they use, pairwise difference analysis, which is a phenetic clustering technique that groups taxa on the basis of the number of differences the taxa exhibit. Thus, their claim to have disproved the Out of Africa hypothesis for modern human origins is without foundation.…”

Neanderthal taxonomy reconsidered: Implications of 3D primate models of intra- and interspecific differences

“…E ver since Neanderthals were first discovered in the 19th century, their specific status and contribution to modern human evolution have been debated. The current controversy centers around two contrasting models for modern human evolution (1,2): the single-origin theory, which frequently views modern humans as a new species arising relatively recently in Africa and replacing indigenous archaic populations around the world; and the regional-continuity model, in which archaic populations contributed to the evolution of modern peoples in each geographic area. Directly tied to these two models is the status of Neanderthals as a distinct species or as a subspecies of Homo sapiens at least partially ancestral to modern Europeans.…”

Untitled

“…Consequently it is a source of considerable disagreement and there may in fact be no one best way of coding continuously variable data." cies (e.g., Wolpoff et al 2001), or two subspecies (Wolpoff 2009), or two species that share a very recent common ancestor (e.g., Rak et al 2002). The recent work on sequencing the Neandertal genome (Green et al 2010) documents some Neandertal-modern human gene flow, yet researchers cannot agree on whether (or where) to draw the species boundaries (Gibbons 2011).…”