Figure 2

Organization of high-level spatial classes in BSPO and some of their children. ‘Anatomical region’ (green fill), ‘anatomical gradient’ (pink fill), ‘anatomical axis’ (blue fill), ‘anatomical plane’ (purple fill), and ‘anatomical surface’ (yellow fill). Parent classes from CARO are shown with white fill. Subclass (is_a) relations are shown in black and spatial relations in orange.