Abstract
The most prevalent version of the environmental hypothesis, by Sherman, would predict a sex difference in spatial performance in Scotland but not in Ghana. With regard to the particular task used, i.e., 3D (3-dimensional) mental rotation, the same prediction would arise on the basis of Serpell''s specific experience hypothesis. Subjects were 40 boys and 40 girls in Ghana and Scotland, equated for years of education. A sex difference of the same magnitude was shown in both cultures, thereby throwing doubt on purely environmental interpretations. The findings also clearly argue against a genetic hypothesis put forward by Jensen.