Language is a hallmark of modern humans: only humans have language. Yet, while no human society lacks a language, individual languages exhibit wide variety. In this, language differs greatly from bipedalism, the other hallmark of humans. Mark Aronoff, Stony Brook University, and Carol Padden, UC San Diego, explore the question of whether there is a relation between the variety among languages and genetic variation, concentrating on the emergence of sign languages in societies with a high incidence of deafness due to genetic traits. They show that the emergence of sign languages in such societies is also tied to a number of preexisting cultural factors. This type of interaction, where genetics and culture, both separately and together, provide the foundation for a particular type of language, has not previously received attention. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 24115]