Pragmatic Inference in Non-Human Great Ape Communication
For research in the evolution of language one question of interest is the extent to which human communicative abilities are shared by our nearest cousins, the non-human great apes. Abilities that are shared with apes can reasonably be supposed to have been present in our last common ancestor (LCA). Abilities that are uniquely human indicate evolutionary changes in the human lineage that occurred since the split from our LCA.
For human communication a very fundamental ability is acting with and attributing communicative intent. This is the domain of pragmatics. It has been hypothesised to play a foundational role in human language development. A central question, then, is whether non-human great apes act with and attribute communicative intent. Since they seem to be relatively poor at pointing comprehension, it has often been claimed that they do not (Tomasello 2006, 2008; Scott-Phillips 2014, 2015). This is thought to be why humans alone acquire language.
In this talk I revisit the question of great ape pointing. Following a brief recap of the empirical data I argue that great apes are better at pointing comprehension than has often been supposed. I additionally argue that the data are better explained by the hypothesis that great apes do understand communicative intent, but are limited in their pragmatic interpretation abilities and also both relatively inattentive to human gestures and often unmotivated to respond to them. Further, I present a theoretical framework within which attributing an understanding of communicative intent to great apes becomes unproblematic. Thus I claim that the comprehension of communicative intent is a point of continuity between our species.
I finish by considering a different adaptation that may have pushed humans down the path towards language. In contrast to great apes, and under selection pressure for cooperative living, we may have undergone selection to look to our peers to learn about the world. In turn this made us more receptive to our peers’ use of intentionally produced gestures in problem solving contexts, and led us to treat them as potentially valuable sources of information about the world. I then apply this hypothesis to the explanation of explaining the differing success of human children and chimpanzees in Stag Hunt tasks. I finish by considering whether the superior social attention of humans is evidence of an adaptation, or potentially something that could have been learned in ontogeny, on the back of human cultural practices.