 Bar-On (2013) distinguishes between Gricean and Post-Gricean approaches to the evolution of language. The former requires an attribution of Gricean speaker meaning to our languageless ancestors which in turn seems to assume intentional actions govern by rationality (‘nonnatural meaning’). This task is as fraught as explaining the evolution of language itself. She thus proposes the latter, specifically a Post-Gricean (Orrigi and Sperber 2000) approach which takes expressive communication (found widely in non-human animal species) as a basis for the emergence of linguistic meaning between signalers and receivers. She states: