ABSTRACT
Figure 3.1 shows on the same scale the brains of a series of mammals with three primates. The progressive increase in the cerebrum is the dominant feature, but the cerebellum increases in parallel, though to a lesser extent. Many other important components of the brain are indicated in the lateral view of the brain and upper spinal cord in Figure 3.2, and in a sagittal section of the brain (Figure 3.3). These figures are adequate for understanding the evolutionary significance of the wide range of primate brains studied initially by Stephan and Andy (1969), and later with a series of papers by Stephan and associates culminating in the recent review (Stephan et al., 1987).
