title: Early development of turn-taking with parents shapes vocal acoustics in infant marmoset monkeys.
abstract: In humans, vocal turn-taking is a ubiquitous form of social interaction. It is a communication system that exhibits the properties of a dynamical system: two individuals become coupled to each other via acoustic exchanges and mutually affect each other. Human turn-taking develops during the first year of life. We investigated the development of vocal turn-taking in infant marmoset monkeys, a New World species whose adult vocal behaviour exhibits the same universal features of human turn-taking. We find that marmoset infants undergo the same trajectory of change for vocal turn-taking as humans, and do so during the same life-history stage. Our data show that turn-taking by marmoset infants depends on the development of self-monitoring, and that contingent parental calls elicit more mature-sounding calls from infants. As in humans, there was no evidence that parental feedback affects the rate of turn-taking maturation. We conclude that vocal turn-taking by marmoset monkeys and humans is an instance of convergent evolution, possibly as a result of pressures on both species to adopt a cooperative breeding strategy and increase volubility.
authors.affiliation: Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA Department of Psychology, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Daniel Y
authors.initials: DY
authors.lastname: Takahashi
authors.affiliation: Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA Department of Psychology, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Alicia R
authors.initials: AR
authors.lastname: Fenley
authors.affiliation: Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA Department of Psychology, Princeton University, Princeton, NJ 08544, USA Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA asifg@princeton.edu.
authors.forename: Asif A
authors.initials: AA
authors.lastname: Ghazanfar
mesh_terms: D000818:Animals; D002144:Callithrix / Q000502:physiology* / Q000523:psychology; D005260:Female; D008297:Male; D016487:Parenting; D014828:Vocalization, Animal
keywords: communicative pragmatics; language evolution; mother–infant; primate vocal development; speech evolution; vocal learning