Current theories of Modern Human origins are divisible into two groups. There are those that promote regional continuity and hybridisation and those that advocate a recent African origin to all Moderns (Klein, 1999). In the first category is the strict Regional Continuity Model (Wolpoff, 1989) which proposes that ancestral populations of an archaic hominid dispersed from Africa across the Old World around 1.9 Myr and that the populations that settled in different parts of the world independently evolved into Moderns. For this to have happened, without the different populations becoming distinct species, the model predicts that there was regular gene flow between populations. Subsidiaries of the Regional Continuity Model have been advanced. Brauer (1992) proposed that there was a degree of regional continuity between populations but that there was a significant African genetic contribution to European and western Asian populations through hybridisation and assimilation. Smith (1992) proposed a similar model but reduced the importance of the African contribution with a smaller number of genes being assimilated by European and western Asian populations. The ‘intermediate’ models would seem to have some support from the genetic evidence (Templeton, 2002).

The late Pleistocene Out-of-Africa Model (Cann et al., 1987; Stringer & Andrews, 1988) is the parent of the rival group. It proposes that Moderns evolved in Africa between 130 and 200 kyr ago, spread out of Africa and replaced all other archaic human populations after 100 kyr ago.