This work follows the direction set by Sewall Wright in applying path analysis, and other multivariate statistical techniques, to the study of anthropometric variation. Data on anthropometric variation of six Solomon Island populations is analyzed using statistical models which can distinguish between within-group and between-group genetic variation. The correlation structure of 27 anthropometric measurements is examined by cluster analysis and principal components analysis. The six populations show a common pattern (in both males and females) which echoes earlier studies. The correlation matrix of measurements is then partitioned into genetic and environmental components and the genetic correlation matrix is examined, once again by cluster analysis and principal components analysis. There is a fairly close agreement between the genetic correlation structure and the phenotypic correlation structure. The environmental correlation matrix is not examined further because it is very poorly estimated. The partitioning of phenotypic correlations into genetic and environmental components is based on a multivariate generalization of a path model for the heritability of a continuous trait proposed by C. C. Li. The parameters estimated in the single trait model include additive genetic heritability, common home environment, and genetic correlation between spouses. In order to fit this model observations are required on parent-offspring, spouse-spouse, and sib-sib correlations. Heritability values for the Solomons are markedly lower than those reported elsewhere. However, when total heritability (ignoring subpopulation structure) is estimated for the six Solomons populations, the values are higher and form a more familiar pattern. The striking differences between the two kinds of heritability in the Solomon Islands emphasizes the danger of using total heritability estimates obtained from several subpopulations or a national sample. The between-group component of heritability for each measurement is compared to the within-group heritability and to levels of between-group phenotypic variation. The results demonstrate that high within-group heritability for a given trait does not imply that between-group variation in that trait is genetic in origin.
| Identifer | oai:union.ndltd.org:ADTP/274404 |
| Date | January 1983 |
| Creators | Black, Stephen James |
| Publisher | ResearchSpace@Auckland |
| Source Sets | Australiasian Digital Theses Program |
| Language | English |
| Detected Language | English |
| Source | http://wwwlib.umi.com/dissertations/fullcit/8323923 |
| Rights | Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated., http://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm, Copyright: The author |
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