How quirk of primate evolution gave humans the voice apes lack

Simplification of larynx let humans have excellent pitch control with long and stable speech sounds

Scientists have identified evolutionary modifications in the voice box distinguishing people from other primates that may underpin a capability indispensable to humankind: speaking.

Researchers said on Thursday that an examination of the voice box, or larynx, in 43 species of primates showed that humans differ from apes and monkeys in lacking an anatomical structure called a vocal membrane: small, ribbon-like extensions of the vocal cords.