September 24, 2004

Taller populations are not more sexually dimorphic in stature

Previously it was thought that taller populations tended to have a greater degree of sexual dimorphism in stature, i.e., that male-female differences in stature were more pronounced in them. A new paper finds that there exists a strong phylogenetic signal in human stature; in other words, human stature variations correspond to some degree with our knowledge of the evolutionary history of modern human populations and the population "splits" which have given rise to modern groups. Moreover, the re-analysis of data from 124 human populations disproves the idea that taller populations are more sexually dimorphic in stature.

Journal of Human Evolution (Article in Press)

Human size evolution: no evolutionary allometric relationship between male and female stature

Anders Gustafsson et al.

In many animal groups, sexual size dimorphism tends to be more pronounced in species with large body size. Similarly, in a previous cross-cultural analysis, male and female stature in humans were shown to be positively allometrically related, indicating a similar relationship where populations with larger stature were more dimorphic. In this study, we re-examine the hypothesis of an allometric relationship between the sexes using phylogenetic methodology. First, however, we tested whether there exist phylogenetic signals in male and female stature. Data on mean stature from 124 human populations was gathered from the literature. A phylogenetic test showed that male and female stature were significantly associated with phylogeny. These results indicate that comparative methods that to some degree incorporate genetic relatedness between populations are crucial when analyzing human size evolution in a cross-cultural context. Further, neither non-phylogenetic nor phylogenetic analyses revealed any allometric relationship between male and female stature. Thus, we found no support for the idea that sexual dimorphism increases with increasing stature in humans.


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