Genetics, Linguistics, and Prehistoric Migrations: An Analysis of California Indian Mitochondrial DNA Lineages

The advent of mitochondrial DNA analysis makes possible the study of past migrations among California Indians through the study of genetic similarities and differences. Four scenarios of language change correlate with observable genetic patterns: (1) initial colonization followed by gradual changes due to isolation; (2) population replacement; (3) elite dominance; and (4) intermarriage between adjacent groups. A total of 126 mtDNA samples were provided by contemporary California Indian descendants whose maternal lineages were traced back to original eighteenth and nineteenth century sociolinguistic groups using mission records and other ethnohistoric sources. In particular, those groups belonging to three language families (Chumashan, Uto-Aztecan, and Yokutsan) encompassed enough samples to make meaningful comparisons. The four predominant mtDNA haplogroups found among American Indians (A, B, C, and D) were distributed differently among populations belonging to these language families in California. Examination of the distribution of particular haplotypes within each haplogroup further elucidated the separate population histories of these three language families. The expansions of Yokutsan and Uto-Aztecan groups into their respective homelands are evident in the structure of genetic relationships within haplogroup diagrams. The ancient presence of Chumashan peoples in the Santa Barbara Channel region can be inferred from the presence of a number of haplotypes arrayed along a chain-like branch derived from the founding haplotype within Haplogroup A. A distinctive Haplogroup D sequence, represented by four Chumash lineages, belongs to a rare subgroup, occurring primarily among groups scattered along the Pacific coast of North and South America. This distribution is consistent with the hypothesis that an early coastal expansion occurred during the initial peopling of the Americas