Lip-Smacking Primate Hints at Speech Evolution
Most primates make rudimentary calls that consist of one or two syllables. But the geladaâ€”native only to the grasslands of the Ethiopian plateauâ€”displays â€œrapid fluctuations in pitch and volumeâ€ akin to human speech.
The similarity has researchersâ€™ tongues wagging.
â€œOur finding provides support for the lip-smacking origins of [human] speech, because it shows that this evolutionary pathway is at least plausible,â€ study leader Thore Bergman, of the University of Michigan in Ann Arbor, said in a statement.
Lip-smacking is unlike other primate calls in that the rhythm corresponds to the opening and closing of parts of the mouthâ€”which in turn, well, smacks of human speech, according to the study authors.