Primate communication: Meaning from strings of calls

How did human language evolve from earlier forms of primate communication? One key transition has been increased motor control during vocalisation, which enables humans to generate and imitate complex vocal patterns. Although humans are unique in this way, evolutionary inventions are usually modifications of earlier adaptations. The purpose of this chapter thus is to survey the recent primate literature for evidence of vocal control. To this end, we are interested in two qualities, acoustic variants of basic call types and call sequences. We find evidence for both in different species of primates, suggesting a direct transition from primate vocal behaviour to human speech. Future research will have to focus on the mechanisms of motor control of the speech-relevant articulators, particularly the larynx, velum, tongue, and lips.