Biological relationships among the Iroquois.

The intrusive cultural and linguistic position of Iroquoian-speaking peoples among Algonquian speakers of the lower Great Lakes region has sparked much debate concerning their cultural and biological origins. Previous physical anthropological studies, largely limited to typological or univariate osteometric analyses, have produced equivocal and contradictory results, offering little insight into the question of origins. This study addresses the question of Iroquois origins by examining biological relationships in the lower Great Lakes region using a multivariate analysis of anthropometric data. The study uses 12 body and head measurements taken on 843 individuals from 7 Iroquoian and 4 Algonquian groups. The data were examined using biodistances, canonical variate analysis, and a model of differential gene flow. The results indicate a possible biological distinction between Iroquoians and Algonquians, suggesting different biological origins. Gene flow in prehistoric and historical times may have mitigated much of this differentiation. The Onondaga most closely approximate the ancestral Iroquoian phenotype and are phenotypic outliers, probably because of reproductive isolation from the Algonquians. The Onondaga have unexpectedly high mean phenotypic variance with respect to distance from the phenotypic centroid, suggesting a greater than average degree of external gene flow. Because no viable source for external genes can be determined, however, the Onondaga's high mean variance may be better explained through patterns of nonrandom mating and reproductive isolation.