The evolution of speech: vision, rhythm, cooperation.

Bibliographic Collection: 
Publication Type: Journal Article
Authors: Ghazanfar, Asif A; Takahashi, Daniel Y
Year of Publication: 2014
Journal: Trends Cogn Sci
Volume: 18
Issue: 10
Pagination: 543-53
Date Published: 2014 Oct
Publication Language: eng
ISSN: 1879-307X
Keywords: Animals, Biological Evolution, Cooperative Behavior, Facial expression, Humans, Interpersonal Relations, Pattern Recognition, Physiological, Periodicity, Speech, Vision, Ocular, Vocalization, Animal

A full account of human speech evolution must consider its multisensory, rhythmic, and cooperative characteristics. Humans, apes, and monkeys recognize the correspondence between vocalizations and their associated facial postures, and gain behavioral benefits from them. Some monkey vocalizations even have a speech-like acoustic rhythmicity but lack the concomitant rhythmic facial motion that speech exhibits. We review data showing that rhythmic facial expressions such as lip-smacking may have been linked to vocal output to produce an ancestral form of rhythmic audiovisual speech. Finally, we argue that human vocal cooperation (turn-taking) may have arisen through a combination of volubility and prosociality, and provide comparative evidence from one species to support this hypothesis.

DOI: 10.1016/j.tics.2014.06.004
Alternate Journal: Trends Cogn. Sci. (Regul. Ed.)