Biological costs of a small stature for homo sapiens females: New perspectives on stature sexual dimorphism

Abstract

The idea that sexual selection can oppose natural selection in favouring costly traits is a Darwinian idea that has been much explored by evolutionary biology within the last 50 years. Sexual dichromatism in birds and sexual dimorphism of body size in mammals represent well known examples of this theoretical issue. In the few theorisations on stature sexual dimorphism (SSD) in the human species, the absence of questioning on costs is unsettling. Considering the reproductive advantage of a big size for mammalian females in general and the obstetrical costs of a small stature for human females in particular, this article explores critically ancient and recent hypotheses advanced for explaining SSD in the human lineage. The reason proposed to the impenetrable lack of theoretical coherence pinpointed here is an epistemic obstacle at the heart of the scientifi c models looking at humans: gendered cultural norms and practices are not seen as potential selective forces that could oppose natural selection and thus favour costly morphological traits in our species.