The evolution of language

The emergence of language was a defining moment in the evolution of modern humans. It was an innovation that changed radically the character of human society. Here, we provide an approach to language evolution based on evolut ionary game theory. We explore the ways in which protolanguages can evolve in a nonlinguistic society and how specific signals can become associated w ith specific objects. We assume that early in the evolution of language, er rors in signaling and perception would be common. We model the probability of misunderstanding a signal and show that this limits the number of object s that can be described by a proto language. This "error limit" is not over come by employing more sounds but by combining a small set of more easily d istinguishable sounds into words. The process of "word formation" enables a language to encode an essentially unlimited number of objects. Next, we an alyze how words can be combined into sentences and specify the conditions f or the evolution of very simple grammatical rules. We argue that grammar or iginated as a simplified rule system that evolved by natural selection to r educe mistakes in communication. Our theory provides a systematic approach for thinking about the origin and evolution of human language.