A case study in the emergence of recursive phrase structure

Phrase structures combine words, phrases, and both, into phrases. Human languages exhibit phrase structure, though it is unclear why, and this issue can be approached from various directions. The aim of this study is to explore the origins of phrase structure from an evolutionary point of view.
We build further on analytical arguments where we proposed concrete selectionist criteria and showed that phrase structure could be motivated by the need to avoid combinatorial search in parsing and semantic ambiguity in interpretation, while always keeping communicative accuracy. We introduce an operational minimal model of communication (a specific language game), together with a language acquisition device, to explain how phrase structure can be achieved and acquired at the individual and collective level.
Surprisingly, the grammars evolved by this operational model also exhibit recursion.