Cortical evolution

The evolution of the cerebral cortex in the earliest mammals over 200 mya was dominated by olfactory cortex (see top figure: Molnar et al, 2015). We have been developing evidence starting with our study of the olfactory cortex (Haberly and Shepherd, 1973) that the functional principles of the olfactory cortex provided the basic organizational plan for the evolution of the neocortex, a concept for which there is increasing support (Krigstein and Connors, 1986; Rowe et al, 2010; Shepherd, 2010; Rowe and Shepherd, 2016; see bottom figure: Shepherd et al, 2017).