The great promise of comparative neuroscience is to understand why brains differ by investigating the
relations between variations in the organization of different brains, their evolutionary history, and their
current ecological niche. For this approach to be successful, the organization of different brains needs to
be quantifiable. Here, we present an approach to formally comparing the connectivity of different cortical
areas across different brains. We exploit the fact that cortical regions can be characterized by the unique
pattern of connectivity, the so-called connectivity fingerprint. By comparing connectivity fingerprints
between cortical areas in the human and non-human primate brain we can identify between-species
homologs, but also illustrate that is driving differences between species. We illustrate the approach
by comparing the organization of the frontal cortex between humans and macaques, showing general
similarities combined with some differences in the lateral frontal pole.