Do the Natives All Look Alike? Size and Shape Components of Anthropometric Differences Among Yanomama Indian Villages

Abstract

This study of anthropometric resemblance between men and women from the same and different villages shows the significance of the distinction between differences in size and differences of shape. Expecting that it might be possible in spite of size differences to detect similarity of shape between men and women from the same local population, I develop a partition of Mahalanobis' D2 into size and shape components and illustrate it with a geometric example. The partition is used with anthropometric data on men and women for 11 villages of the Yanomama Indians, and results are presented in an analysis of variance, modified to accommodate multidimensional observations. The analysis demonstrates that once gross size differences have been partitioned out, men and women from the same village are morphologically (i.e., in shape) more similar than men and women from different villages. It is inferred that this observation of within-group similarity for anthropometric data is a counterpart to the known genetic differentiation among Yanomama villages.