This study used some of the data from the BBC Internet study to assess the universality of sex related spatial competencies, as these are described in the terms of Silverman and Eals’ (1992) hunter-gatherer theory of human spatial sex differences. As predicted, men scored significantly higher than women on a test of three-dimensional mental rotations in all seven ethnic groups and 40 countries used. Close to prediction, women scored significantly higher than men on a test of object location memory in all seven ethnic groups and 35 of the 40 countries. The data were discussed in terms of their implications for research approaches in this area and a paradigm for future studies was proposed, based on the interaction of innate and environmental factors in the ontogenetic development of spatial sex differences.