The human arcuate fasciculus (AF) is a dorsal pathway crucial for language ability. Although chimpanzees have an AF homologue, whether monkeys have one too is controversial. Diffusion MRI data from humans, chimpanzees and macaques showed that, like chimpanzees, macaques have a homologous, bilateral connection from the auditory cortex to the inferior frontal cortex, in both hemispheres. These findings support the hypothesis that language arose through the evolution of primate auditory pathways.
Balezeau, F. et al. Primate auditory prototype in the evolution of the arcuate fasciculus. Nat. Neurosci. 23, 611–614 (2020)