[Population structure of the forest Nentsi: demographic characteristics, marriage structure, migration and an analysis of mixing].

This report is a third one in a series of works devoted to the genetic structure (biodemographic studies) of the Forest Nentsy. The main parameters of the population studied were as follows: the total number in seven subpopulations amounting to 1734 persons, the sex ratio 0.93, percentage of children in the group of 0 to 15 years old--39,1%, reproductive and effective sizes--29,5% and 22,0%, respectively, the mean number and variance of offspring per mating, when reproduction is completed being 2,7 (5,2). It has been shown that kin and territorial subdivision of the population contributes to the formation of conjugal pairs and migration pattern. Within-kin matings make 0,041, whereas, according to the panmixia hypothesis, this value would be 0,243. The average index of isolation for particular subpopulation is 62,7%. An exchange of migrants occurs between adjacent groups. Migration stream to the different subpopulations varies in volume and ethnic composition. Analysis of the admixture based on the pedigree isoname method has shown that the proportion of the Forest Nentsy gene contribution to their own population is 74,4%. Data on subpopulation size, patterns of matings, migration and admixture may serve as a basis to account for intrapopulation heterogeneity.