Experimental Studies on the Cultural Evolution of Language

Why are languages the way they are? The biases and constraints that explain why languages display the traits they do --instead of other possible ones-- include human cognition, social dynamics, communicative function, the structure of meanings, and the interactions between these. Cultural language evolution is concerned with explaining the causal pathways that link these biases and constraints with fundamental linguistic traits, such as combinatoriality, compositionality, conventionality and arbitrariness. The cultural evolution of language, or the emergence of a language from no language, begins when motivated signals are used in context by individuals who do not share a means of communication. Repeated interaction between interlocutors makes individual signals compressible through reduction or simplification and can entrench idiosyncratic patterns. Transmission to new learners results in the increasing compressibility at the level of the system through the introduction of categories and regular rules, and in the spread of conventional, arbitrary signals.