The ethnographic evidence shows that three of the four subgroups studied belong to the same gamic unity, with the fourth subgroup belonging to another gamic network. On the other hand, the intergroup approach detected a level of variation significantly greater among females than among males.
Individual mean per locus heterozygosities were not different between the sexes, and the analysis of genetic heterogeneity showed similar gene frequencies for males and females in all villages. The results were only partly concordant with the expected. We investigated the within-group and between-group genetic variability among males and females from 4 villages of an uxorilocal Amazonian tribe, the Urubu-Ka'apor, on the basis of 20 polymorphic loci. Despite a recent attempt to interpret this phenomenon in terms of population genetics (Konigsberg 1988), the main assumption has never been tested in situations in which the real residential practice of an indigenous population is known and in which genetic rather than phenotypic data are available.
These studies, which focus on the sexual distribution of skeletal traits, assume that the degree of intragroup or intergroup biologic diversity is higher in one sex with regard to unilocality (uxori- or virilocality). In prehistoric contexts, therefore, an intergroup genetic approach can provide more reliable grounds for sociocultural inferences.The analysis of biologic variation in prehistoric human populations separately by sex has been used as a tool to recover post-marital residential rules. Such results suggest that the intergroup analysis is more sensitive to the genetic effects of differential migration rates between the sexes. Within-sex differences in intergroup analysis turned out to be more evident yet, when those 3 villages were investigated separately, the female FST (0.0609) proved to be significantly higher than the male FST (0.0218). The ethnographic evidence shows that three of the four subgroups studied belong to the same gamie unity, with the fourth subgroup belonging to another gamie network.
The analysis of biologic variation in prehistoric human populations separately by sex has been used as a tool to recover post-marital residential rules.