First evidence of a primate other than humans using vocal feedback to shift from cries to adult communication
Small monkeys with white tufts of ear hair and long, striped tails may reveal some surprising new insights into how human infants learn to make speech sounds.
During the first two months of life, common marmoset monkeys (Callithrix jacchus) transform their initial cries into whistlelike calls known as “phees,” at least in part by imitating their parents’ well-timed calls, says a team led by psychologist Asif Ghazanfar of Princeton University. This is the first evidence of a nonhuman primate using vocal feedback early in life to learn how to produce mature communication sounds, the researchers report in the Aug. 14 Science.
Vocal learning plays out in marmosets much as it does in humans and songbirds, the researchers propose. In each, certain early vocal sounds gradually get modified into mature sounds via physical