togog: Subproject P5c

The ontogeny of gestural communication in non-human great apes

Researchers: Christel Schneider, and Katja Liebal



To document the acquisition of gestures across species (bonobos, chimpanzees, gorillas, and orangutans).

Different mechanisms that presumably play a role in the acquisition of gestures in great apes have been proposed; these range from genetic determination, ontogenetic ritualisation to forms of social learning, such as imitation. However, there are almost no longitudinal studies investigating the use of gestures in young apes apart from a few case studies. Thus, the aim of this subproject is to shed light on the mechanisms of gesture acquisition in all non-human great ape species over the period from 0 – 20 months. Data on 25 individuals (including bono­bos, chimpanzees, gorillas, and orangutans) have been collected, resulting in a data corpus of more than 500 hours of weekly and biweekly observations. To develop individual profiles of gesture use, 20 minutes per month and per individual have been analyzed so far. The data show that gesture use increases with age, with visual gestures appearing at a very early stage; this finding contradicts Tomasello and Camaioni’s (1997) view that visual gestures require more complex cognitive skills and therefore only emerge later in ontogeny. To be able to conduct a statistical analysis and to compare gesture use across individuals, ages and contexts, more data are currently being coded, resulting in a larger data set and a better picture of what is going on in apes' gestural communication during the first years of life.