This book explores how language is acquired via enculturation. It combines research and perspectives from anthropology, sociology, applied linguistics, developmental psychology and neurobiology to argue for a theory of language acquisition via enculturation. The first part of the book examines the practices by which we are enculturated. Indeed, members of a society are socialized into their culture, and more specifically to use language through language via processes that include eavesdropping, observation, participation, imitation, and language socialization. However, ethnographic accounts also overwhelmingly show that children become enculturated in large part on their own initiative. Thus, the second part of the book argues for a motivation to attune to, seek out, and become like others - or an Interactional Instinct, which facilitates enculturation and the biology that subserves it. The final chapters explore more of our biological readiness and the neurological structures and systems that may have evolved to respond to the input provided by society to facilitate the learning of cultural practices and traditions by its youth. The picture that emerges indicates that biology is nature and culture is nurture, but there is no nurture without nature, and it is nurture that provides for the phylogenetic development of our biological nature. The ontogenesis of language behavior, i.e. its acquisition, cannot occur without its evolved biology or without its evolved cultural practices for socialization.

The Interactional Instinct explores the evolution of language from the theoretical view that language could have emerged without a biologically instantiated Universal Grammar. In the first part of the book, the authors speculate that a hominid group with a lexicon of about 600 words could combine these items to make larger meanings. Combinations that are successfully produced, comprehended, and learned become part of the language. Any combination that is incompatible with human mental capacities is abandoned. The authors argue for the emergence of language structure through interaction constrained by human psychology and physiology.
In the second part of the book, the authors argue that language acquisition is based on an "interactional instinct" that emotionally entrains the infant on caregivers. This relationship provides children with a motivational and attentional mechanism that ensures their acquisition of language. In adult second language acquisition, the interactional instinct is no longer operating, but in some individuals with sufficient aptitude and motivation, successful second-language acquisition can be achieved.
The Interactional Instinct presents a theory of language based on linguistic, evolutionary, and biological evidence indicating that language is a culturally inherited artifact that requires no a priori hard wiring of linguistic knowledge.

The Interactional Instinct explores the evolution of language from the theoretical view that language could have emerged without a biologically instantiated Universal Grammar. In the first part of the book, the authors speculate that a hominid group with a lexicon of about 600 words could combine these items to make larger meanings. Combinations that are successfully produced, comprehended, and learned become part of the language. Any combination that is incompatible with human mental capacities is abandoned. The authors argue for the emergence of language structure through interaction constrained by human psychology and physiology.
In the second part of the book, the authors argue that language acquisition is based on an "interactional instinct" that emotionally entrains the infant on caregivers. This relationship provides children with a motivational and attentional mechanism that ensures their acquisition of language. In adult second language acquisition, the interactional instinct is no longer operating, but in some individuals with sufficient aptitude and motivation, successful second-language acquisition can be achieved.
The Interactional Instinct presents a theory of language based on linguistic, evolutionary, and biological evidence indicating that language is a culturally inherited artifact that requires no a priori hard wiring of linguistic knowledge.