Evolution of the Cerebral Cortex

The largest component of the mammalian cerebral cortex is the neocortex, which has several structural, morphological, and compositional differences that make it a derived mammalian trait. While basic features are shared across species, the mammalian neocortex across species is highly varied due to differences in cortical circuitry, such modular organization and local processing, as well as neuronal morphology and subtype distribution, which likely reflect cortical specializations necessary for behavioral adaptation to a given ecological niche. Such variation in cortical microstructure suggests that rather than large-scale changes in size, cognitively significant evolutionary shifts, such as those seen in human evolution, are likely due to subtle cortical modifications.