Language is a human cognitive specialization, and as such, is expected to be supported by human neurological specializations. The arcuate fasciculus is a white matter fiber tract that connects Wernicke's and Broca's language areas in the human brain, and also connects the homologues of Wernicke's and Broca's areas in non-human primate brains. Emory University professor James Rilling discusses the difference of arcuate fasciculus between human and non-human primate brains and how the specialization of speech has helped humans evolve. (#37381)