The macroevolution of brain size and cortical association areas in primates

Brain evolution has been studied by macroevolutionary analysis and comparisons among model species. Integrating these two approaches would benefit from studying phenotypes amenable to a combined evolutionary, developmental, genetic/genomic, functional, and biomedical perspective. Here we discuss the size of the brain and cortical association areas and note that the pattern that best describes their evolution involves bursts of change along particular lineages, which ‘propel’ entire clades onto different evolutionary trajectories. Such bursts provide unique opportunities to analyze the evolutionary processes that shape neurodevelopment, promising a deeper understanding of the evolutionary molecular basis of human brain development and brain disorders.