We report a search for group differences in color experience between mate and female subjects, focusing on the relative prominence of the axes of color space. Dissimilarity data were collected in the form of triadic (odd-one-out) judgments, made with the caps of the D-15 color deficiency test, with lighting conditions controlled. Multidimensional scaling reduced these judgments to a small number of dimensional-weight parameters, describing each subject's sensitivity to color axes, i.e., how much each axis contributes to the inter-color dissimilarities perceived by each subject. Normal trichromatic subjects in two age bands were examined, teenagers and university students, and in both cases males placed significantly less weight on a 'red-green' axis, and more on 'lightness'. We consider the implications and possible explanations. (C) 2004 Wiley Periodicals, Inc.