Context-sensitive adjustment of pointing in great apes

Abstract

The present research was non-invasive and strictly adhered to the legal requirements of Germany. The methods were carried out in accordance with the relevant guidelines and regulations. Animal husbandry and research complied with the European Association of Zoos and Aquaria (EAZA) Minimum Standards for the Accommodation and Care of Animals in Zoos and Aquaria and the World Association of Zoos and Aquariums (WAZA) Ethical Guidelines for the Conduct of Research on Animals by Zoos and Aquarium.

Inferential Communication: Bridging the Gap Between Intentional and Ostensive Communication in Non-human Primates

“…For example, great apes successfully differentiated between the same action from a human experimenter, producing more begging and impatience behaviors when the experimenter's action could be interpreted as "unwilling" to provide food versus "unable" to provide food (Call et al, 2004). From the production side, apes were able to modify the shape and location of their pointing behavior when their options were arranged such that a simple forward point would be ambiguous, suggesting that they recognized the need to disambiguate their pointing for the experimenter's successful comprehension and that they were able to apply that understanding to their actual gestures (Tauzin et al, 2020). Furthermore, great apes will monitor the success of a relatively ambiguous signal (e.g., begging), and elaborate with different, additional gestures (e.g., pointing at the desired option), if the desired outcome is not achieved (Leavens et al, 2005).…”

“…Conversely, if contextual cues are ambiguous, would signals become more specific? There exists some experimental evidence that apes use pointing variations to disambiguate between two food items when the higher-value food was placed behind a lower value food and subjects were asked to select their preferred food, via pointing (Tauzin et al, 2020). A similar paradigm could investigate whether apes use modified pointing gestures to disambiguate between choices where the context is identical, but their knowledge of the recipients' past experiences or preferences is varied.…”

Fifteen ways of looking at a pointing gesture

“…A counterpoint to these claims, as Leavens (2012) notes, is that apes trained to use a natural human language do point declaratively and with the index finger (see Gardner & Gardner, 1969;Lyn, Greenfield, Savage-Rumbaugh, Gillespie-Lynch, & Hopkins, 2011). Recent results also suggest that captive chimps use pointing as flexible signal, raising their arms higher to point to further targets (Gonseth, Kawakami, Ichino, & Tomonaga, 2017;Roberts, Vick, Roberts, & Menzel, 2014)-much as humans do (e.g., Mesh, 2017)-and adapting their gestures 44 in other ways to fit the communicative context (Tauzin, Bohn, Gergely, & Call, 2020). In short, apes do point-flexibly and even declaratively-provided sufficient human scaffolding and interaction, but pointing can hardly be said to be a natural proclivity.…”

Being ostensive (reply to commentaries on ‘Expression unleashed’)

“…Further experimental protocols, suitable for comparisons across species, would be hugely informative, and would complement existing studies on the production side showing that chimpanzee pointing behavior can be dependent on what is or is not in the common ground (e.g. Bohn et al, 2015;Tauzin et al, 2020).…”