Evolution of the brain and phylogenetic development of African Bovidae

Abstract

Evidence drawn from the study of 270 brains of 54 species and subspecies of African Bovidae makes it possible to base phylogenetic relationships on the similarities in the pattern of the cerebral sulci. Comparison of individual sulci of the cerebral cortex show that, despite individual variation, most genera can be characterized by distinctive patterns. A classification of the genera based on these patterns, after standardization, shows that they fall into seven discrete groups which, as a whole, agree with authorities such as Allen (1954) and Ansell (1971), who divide the family into 11 subfamilies. The surface area of the neocortex in the several genera is calculated revealing different levels of evolution in the subfamilies. This does not suffice as the only bases of comparison as the possibility of differences in the number of nerve cells remains. The neocortex development appears to be related to the social organization, feeding habits and the extent of similarity between the sexes.