The multiregional and single origin hypotheses of the evolution of modern man: a reconciliation.

A current debate opposes two theories of the origin of modern man. One view is that modern Homo sapiens emerged from Africa relatively recently, most probably within the last two or three hundred thousand years (Wilson & Cann, 1992, Sci. Am. 266(4), 22-27). The opposing view is that modern man has resulted from parallel evolution in different regions, producing convergent modernization of local populations over the last million years or so--the multiregional model (Frayer et al., 1993, Am. Anthrop. 95, 14-50). Proponents of both views believe that their interpretations are irreconcilable. The object of the present paper is to describe a genetic mechanism--mitochondrial exclusion--which offers a basis for a model of human evolution that is compatible with the evidence adduced for both contemporary views. The model proposes a mechanism by which complete replacement of archaic mitochondrial DNA may have occurred in a population produced by recent admixture of archaic and modern types of man.