Production and use of vocal communication and language: factors structuring variability

Our multispecific comparative approaches of non-human animals as well as our developmental approaches in particular in humans, contribute to the longstanding scientific debate on the dichotomy opposing human language to other mammals’, mainly primates’, vocalizations. This research axis focuses on individual, social and contextual factors structuring inter- and intra-individual variations of both production and use of vocal communication and language.

Intrinsic factors: vocal encoding of emitter’s characteristics

By applying acoustic analysis tools, we aim to evidence aspects of vocalizations used for an individual’s identity and its characteristics (age, sex, morphology, physiological status). The context of production and its emotional valence are also taken into account.

Extrinsic factors: social influence, vocal sharing and convergence in social networks

An individual’s degree of integration, relationships and interactions in a social network are important extrinsic factors that structure variation in both animal vocal communication and human language. Thus, variation is not randomly distributed in individual vocal repertoires. We aim to establish relationships between the function of a call and its variability.

Parents, as one of many social influences, are often their offspring’s primary models, in particular for their vocal development. Social factors structure variation in human language (social and geographical variation, dialects). We evaluate children's general language skills and acquisition of sociolinguistic variations in relation to factors such as a child’s age and sex, family socio-economic status, and parent-child interactions. We are also interested in the influence played by primate mothers in this context.

children's general language skills and acquisition of sociolinguistic variations

In addition, we take other social factors into account to explain similarities of acoustic features and convergence between vocal learners (dolphins) as well as non-vocal learners (non-human primates).

similarities of acoustic features and convergence

Our research challenges the idea that non-human primates’ vocal plasticity is limited. Social factors influencing humans’ acquisition of language variations extend beyond family to affinitive peers. Even during their preschool years, children’s sociolinguistic uses converge among classmates over time in relation to their social integration and interactions within their peer group.

children’s sociolinguistic uses: influence of their peer group

Emitters’ adjustments to the situational context of communication

Non-human primates' control over the acoustic structure of their vocalizations is expressed by short-term vocal convergence between partners or vocal accommodation in relation to context. We are interested in both human and non-human primate parents' adjustments to their offspring. We also study children’s adjustments of their sociolinguistic uses in relation to their partners’ identity within their family and peer networks.

Main features

  • Voices lower with age and size in various mammals. [FIG1]
  • Family socio-economic status influence on children’s early language development and the acquisition of sociolinguistic variations between 2 and 6 years old. [FIG2]
  • ”Vocal sharing” by free-ranging female Campbell’s monkeys. [FIG3]
  • Children’s sociolinguistic uses convergence within their peer group after a year of daily contacts at nursery school. [FIG4]
  • School-age children adjust their sociolinguistic uses, particularly concerning regional linguistic varieties, according to their interlocutor’s identity in their family and friend networks. [FIG5]