unrelated, species. he believed that this “comparative approach” would reveal both general principles of the nervous system, and offer insights into which nervous system properties (anatomical, physiological, and chemical) were relevant to observed differences in species-specific traits, as well as which specific traits were relevant to observed differences in nervous systems. his resulting discoveries helped explain various properties of nervous systems. in one influential review he wrote, “comparative neuroscience is likely to reach insights so novel as to constitute revolutions in understanding the structure, functions, ontogeny, and evolution of nervous systems. […] without due consideration of the neural and behavioral correlates of differences between higher taxa and between closely related families, species, sexes, and stages, we cannot expect to understand nervous systems or ourselves”.