Videos of grunting, cooing show macaques could make key vowel, consonant sounds
Macaque monkeys would be quite talkative if only their brains cooperated with their airways, a new study suggests.
These primates possess the vocal equipment to speak much as people do, say evolutionary biologist and cognitive scientist W. Tecumseh Fitch of the University of Vienna and colleagues. But macaques lack brains capable of transforming that vocal potential into human talk. As a result, the monkeys communicate with grunts, coos and other similar sounds, the scientists conclude December 9 in Science Advances.
“Macaques have a speech-ready vocal tract but lack a speech-ready brain to control it,” Fitch says.
His team took X-ray videos of an adult macaque’s vocal tract while the animal cooed, grunted, made threatening sounds, smacked its lips, yawned and ate various foods. Measures of shifting shapes during these vocalizations allowed the researchers to estimate what