Anthropometric variation and population structure of the island of Pag, Croatia

Human Biology, Apr 1994 by Smolej-Narancic, N, Chaventre, A, Rudan, P

SAMPLE AND METHODS

Measurements were taken by one member of the research team during field investigations in June 1986. Nine-hundred fifteen persons were examined (405 males and 510 females), age 19 to 84 years. The subjects were the inhabitants of four settlements from the northwestern part of the island (1, Lun; 2, Stara Novalja; 3, Novalja; 4, Kolan), six settlements from the southeastern part of the island (5, Pag; 6, Gorica; 7, Dinjiska; 8, Miskovici; 9, Vlasici; 10, Povljana), and three settlements from the northern part of the island (11, Kustici; 12, Zubovici; 13, Metajna) (see Figure 1). For the sake of simplicity, the northwestern part of the island will be referred to as the western part of the island and the southeastern part will be referred to as the eastern part. (Figure 1 omitted.)

The number of subjects in each settlement and their average age are shown in Table 1. Samples from four settlements are excluded from the analyses. These are samples from villages 6 (Gorica) and 8 (Miskovici), which have small population sizes, and samples from towns 3 (Novalja) and 5 (Pag), which are not equally representative of the total population (only 2% of the inhabitants were examined). In the remaining nine villages 16.5-35.3% of the total population was represented in the analyses. They comprised 361 males and 437 females. The age ranges and age distributions are similar in those nine samples. Because anthropometric measurements are influenced by age, it was necessary to estimate variation in the average age between the village samples. Variance analysis showed that only the female samples were significantly heterogeneous in mean age (p

The 24 body and 14 head variables listed in Table 2 were all taken according to the IBP recommended technique (Weiner and Lourie 1969) using standard anthropometric instruments (Sieber-Hagner, Switzerland).

Data processing was performed on a DATAMINI AT 386 (IBM PC-compatible) computer using SPSS/PC software (SPSS Inc. 1987) and additional new programs. Multivariate analyses of variance and discriminant analyses were carried out for the groups of body and head variables to examine the degree and the pattern of between-group phenotypic variation. To estimate the minimum degrees of genetic divergence in the island population using anthropometric data, the minimum F sub ST was derived following the analytical framework of Williams-Blangero and Blangero (1989). They have shown that, assuming additive genetic variation and an underlying polygenic model for quantitative traits, the minimum F sub ST based on phenotypic data is less than or equal to the genetic F sub ST. The minimum F sub ST was calculated according to where t is the number of traits, g is the number of groups, W sub i is the relative census size of the ith group, and C sub p(ii) is the phenotypic distance of the ith group from the population centroid. The C sub p(ii) are the diagonal elements of the standardized phenotypic codivergence matrix C sub p, obtained using phenotypic traits scaled by the inverse of the pooled within-group phenotypic covariance matrix.