Humboldt Research Group
Comparative Gestural Signalling
This independet research group is funded by a Sofja-Kovalevskaja Price of the Humboldt Foundation, which has been awarded to Simone Pika in November 2010.
“As a feature of life on earth, language is one of science’s great remaining mysteries” (Knight, Studdert-Kennedy & Hurford 2000:1).
From early childhood on, human children produce a rich array of sounds, a manifestation of their potent urge to engage in communicative activities, obtain objects, and affect the thinking and behaviour of other people. Speech consists of over 100 acoustically unique phones, commonly combined into rapid sequences, which serve as the main carriers of meaning. These two characteristics — a rich acoustic portfolio and the predisposition to combine basic units into more complex acoustic strings — appear to be unique to the human species, and call for an evolutionary investigation.
A powerful tool to problems of language evolution is provided by the comparative approach, which uses empirical data from living species to draw detailed inferences about extinct ancestors.
So far, the majority of studies related to language origins have focused mainly on vocal abilities of other animal species. However, in addition to the acoustic modality, human language encompasses other means of communication: gestures, specifically movements of the limbs, or head and body postures
Children undergo a gestural phase before they use their first spoken words and use gestural pointing, giving and showing to signal the desire for a specific item and/or joint attention to a specific object.
Concerning comparative studies to gestural abilities, recent research has shown that like human children, apes
• use their gestures as intentional strategies to influence the behaviour of others (e.g. Pika, Liebal, Call & Tomasello 2005);
• utilize their gestures in dyadic and triadic interactions (e.g. Pika 2008a, 2008b) and,
• acquire the majority of gestures via individual learning, although social learning may play a role in the acquisition of some gestures (e.g. Pika, Liebal, Call & Tomasello 2005; Pika 2008a).
However, the majority of studies comparing gestural abilities between human and non-human primates have focused principally on gestural skills of western cultures and non-human primates in captivity. In addition, Boesch (2007) has questioned the validity of the methods used in comparative studies of apes and humans on two counts. First, within-species variability has not been taken into account. Secondly, methodological designs have differed systematically between species. In response, Tomasello and Call (2008) have emphasized that it is not always possible or indeed desirable either to use identical methods across species (e.g. children are motivated in experiments to pursue small toys, while chimpanzees are not).
In order to go beyond this intriguing debate, the CGS group aims to offer a substantially new approach to gestural origins by combining an anthropologically informed comparison of several different human cultures with a taxonomically informed comparison of several closely related species. Because there is reason to believe that the same mechanisms may be also important for other species living in comparably complex social settings (e.g. fission-fusion societies), possibly occurring through a process of convergent evolution, the project also aims to enable the first systematic cross-taxa comparison of gestural skills.