What sign language creation teaches us about language.

How do languages emerge? What are the necessary ingredients and circumstances that permit new languages to form? Various researchers within the disciplines of primatology, anthropology, psychology, and linguistics have offered different answers to this question depending on their perspective. Language acquisition, language evolution, primate communication, and the study of spoken varieties of pidgin and creoles address these issues, but in this article we describe a relatively new and important area that contributes to our understanding of language creation and emergence. Three types of communication systems that use the hands and body to communicate will be the focus of this article: gesture, homesign systems, and sign languages. The focus of this article is to explain why mapping the path from gesture to homesign to sign language has become an important research topic for understanding language emergence, not only for the field of sign languages, but also for language in general. WIREs Cogn Sci 2013, 4:201-211. doi: 10.1002/wcs.1212 For further resources related to this article, please visit the WIREs website.