The phylogenetic foundations of discourse coherence: a pragmatic account of the evolution of language

In this paper we propose a pragmatic approach to the evolution of language based on analysis of a particular element of human communication: discourse coherence. We show that coherence is essential for effective communication. Through analysis of a collection of neuropsychological and neurolinguistic studies, we maintain that the proper functioning of executive processes responsible for planning and executing actions plays a key role in the construction of coherent discourses. Studies that tested the discursive and conversational abilities of bonobos have showed that apes are unable to construct a flow of discourse governed by coherence, and therefore, apes’ conversational interactions are quite different from those of humans. We then propose that the emergence of coherence in communication occurred after the split between great apes’ and humans’ lines of descendants and that this emergence might have been the result of a specific gradual development in the course of hominin evolution of the executive functions.