Figure 7 Three models of human evolution during the Pleistocene. The candelabra model proposes that the transition from H. erectus to H. sapiens occurred independently in different parts of the World. The African replacement model proposes that populations of H. erectus and archaic H. sapiens became extinct in Asia and Europe and were replaced by anatomically modern humans immigrating from Africa. The multiregional model proposes regional continuity and local selection pressures in different parts of the world, but with gene flow (indicated by the dashes connecting the vertical lines that represent different regional populations) due to occasional migrations between populations.

diverged from the lineage of African apes and humans about 13 Myr B.P.

H. erectus spread out of Africa shortly after its emergence from Homo habilis. Fossil remains of H. erectus are known from Indonesia (Java), China, and the Middle East, as well as Africa (Gibbons, 1994). H. erectus fossils from Java have been dated 1.81 ± 0.01 and 1.66 ± 0.04 Myr B.P. (Swisher et al., 1994). There are three models concerning the geographic origin of modern humans: candelabra, African replacement, and multiregional (Figure 7).

The candelabra model was proposed by Carleton S. Coon (1962), who argued that ''Homo erectus evolved into Homo sapiens not once but five times, as each subspecies, living in its own territory, passed a critical threshold from a more brutal to a more sapient state." Moreover, the threshold was crossed at different times, the Caucasoid race becoming sapiens first, whereas the Congoloids reached the sapiens condition some 200,000 years later. Coon's proposal was effectively criticized by several authors who pointed out the impossibility that the same species would



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