Genetic evidence on origin and dispersal of human populations speaking languages of the Nostratic macrofamily.

Contemporary patterns of allele frequencies allow inferences on past evolutionary processes. L.L. CavalliSforza [(1988) Munibe 6, 129-137] and C. Renfrew [(1991) Cambridge Archaeol. J. 1, 3-23] proposed that neolithic farmers from the Near East propagated a group of related ancestral languages, from which three or four linguistic families developed. Here we show that genetic variation among Indo-European, Elamo-Dravidian, and Altaic speakers (grouped by some linguists in the Nostratic macrofamily) supports this hypothesis, whereas the evidence on Afro-Asiatic speakers is ambiguous. Gene-frequency clines within these linguistic families suggest that language diffusion was largely associated with population movements rather than with purely cultural transmission. Archeological, linguistic, and genetic evidence can be reconciled by envisaging a process of population growth and multidirectional dispersal from the Near East as the main factor shaping genetic and linguistic diversity in Eurasia and perhaps in North Africa.