Neocortex size predicts group size in carnivores and some insectivores

Neocortex size has been shown to correlate with group size in primates. Data for carnivores and insectivores are used to test the generality of this relationship. The data suggest that carnivores lie on the same grade as the primates, hut that insectivores lie on a separate grade to the left of these two orders. Among the insectivores, there appears to be a distinction between the 'advanced' genera (which show a relationship between group size and neocortex size) and the 'basal' genera (which do not).