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

Abstract

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. 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.

Book Review

“…They stress sexual dimorphism in the Mladec samples and thus analyzed them separately, finding the retention of Neandertal morphology only in male crania. While the debate over the Mladec crania has already been reported (Wolpoff et al, 2001) and criticized (Bräuer et al, 2004), their conclusion keeps in line with the regional continuity theory of human evolution. By contrast, the morphometric study of the neurocranium by Weber et al indicates that the geometries of the Mladec neurocrania are well fitted to those of AMHS (anatomically modern Homo sapiens), while the occipital morphology exhibits a wide range of overlap between archaic and modern specimens and thus fails to assign confident taxonomic positions.…”

A critique of the chronometric evidence for hominid fossils: I. Africa and the Near East 500–50ka

“…However, debate continues (Cann, 2002;Templeton, 2002;Thorne and Wolpoff, 2003;Bräuer et al, 2004), with the details of both models contested, though there is more extensive debate within the out-of-Africa school (e.g., McBrearty and Brooks, 2000). Within these debates, some dates on fossils are widely accepted (e.g., dates of ca.…”

Recovering the geographic origin of early modern humans by realistic and spatially explicit simulations

“…This view is also supported by the overall larger extent of genetic diversity (Excoffier 2002;Tishkoff and Williams 2002) and lower levels of linkage disequilibrium (e.g., Tishkoff et al 1996;Gabriel et al 2002) in Africa, as well as the persistence in Africa of most ancestral forms of nuclear genes (Takahata et al 2001;Satta and Takahata 2004). This RAO model is challenged by the persistence of morphological characters from Homo erectus to modern humans on different continents (Wolpoff 1989;Wolpoff et al 2000; but see Brauer et al 2004), by the old ancestry of several nuclear genes , or the inference of pre-H. sapiens range expansions from current patterns of molecular diversity (e.g., Templeton 2002). While the RAO model or one of its extensions seems the most likely (Excoffier 2002), it has not been formally tested against competing models.…”