Points of comparison : what indicating gestures tell us about the origins of signs in San Juan Quiahije Chatino sign language

New languages emerge under rare conditions, when deaf children who cannot access the vocal-auditory language(s) used around them invent visual-manual communication systems of their own. Such homesign or family sign systems have simple structures but nevertheless show the hallmarks of language, including a stable lexicon of signs composed of meaningful, recombinable elements. Prior research has found that many of these elements are invented by signers, though some are adapted from the gestural input received from hearing interlocutors. The current project returns to this claim, examining the influence of gestures on the structure of two emerging family sign languages used in a rural, indigenous community in Oaxaca, Mexico. It focuses on foundational, visually accessible ‘indicating gestures’ such as pointing that direct the addressees attention to a region in physical space. Three linked studies were performed to investigate whether indicating gestures have internal structure that is accessible to deaf signers, and whether such structure is incorporated into their emerging languages. In the first, the spontaneous, speech-linked indicating gestures of hearing people were examined for internal structure. They were found to comprise three recombinable elements that, through systematic modulations in form, convey information about the direction and distance of targets. A second study looked for a relationship between the form of indicating gestures and the features of the speech that accompanies them. No such relationship was found, suggesting that the meaningful modulation of the gesture features occurs independently from speech. The final study compared the forms and meanings of two deaf signers’ indicating gestures with those of the hearing participants. Signers were found to use the direction and elbow height features, but not the handshape features, from the conventional indicating system. These findings reveal that indicating gestures, often described as holistic, non-composite signals, in fact exhibit an internal structure that can be incorporated into an emerging signed language. Interestingly, they also reveal that not all features of gestures—even ones that exhibit clear patterning—will be adopted by signers, perhaps because gesture features must be both systematically patterned and visually iconic for signers to interpret them as meaningful.