Evolving artificial sign languages in the lab: from improvised gesture to systematic sign

Abstract

Recent work on emerging sign languages provides evidence for how key properties of linguistic systems are created. Here we use laboratory experiments to investigate the contribution of two specific mechanisms– interaction and transmission–to the emergence of a manual communication system in silent gesturers. We show that the combined effects of these mechanisms, rather than either alone, lead to a gradual increase of regularity, systematic structure and communicative efficiency. The gestures initially produced by participants are unsystematic and resemble pantomime, but come to develop key language-like properties similar to those documented in newly emerging sign systems.