The Technical Brain

In this chapter I discuss the data for tool use having driven increases in brain size. Because humans habitually make and use tools and because hominid brain size appears to have increased around the time that we see tools in the fossil record, tool use has been suggested to be key to increasing brain size. As an increasing number of animals are being shown to use tools, and sometimes to make them, there is an opportunity to use the comparative method to examine whether tool making really has led to brain size increases. I discuss issues with attributes of tasks used to test physical cognition and propose that nest building is a plausible model behaviour with which to look at all aspects of physical cognition, including its neural bases. I conclude that the data are far too few to give much support to the Technical Brain Hypothesis.

Primate tool use and the socio-ecology of thinging: how non-humans think through tools

While ecological psychology and embodied approaches to cognition have gained traction within the literature on non-human primate tool use, a fear of making assumptions on behalf of animal minds means that their application has been conservative, often retaining the methodological individualism of the cognitivist approach. As a result, primate models for technical and cognitive evolution, rooted in the teleological functionalism of the Neo-Darwinist approach, reduce tool use to the unit of the individual, conflating technology with technique and physical cognition with problem-solving computations of energetic efficiency. This article attempts, through the application of material engagement theory, to explore non-human primate technology as a non-individualistic phenomenon in which technique is co-constructed through the ontogenetic development of skill within a dynamic system of structured action affordances and material interactions which constitute an emergent, species-specific mode of technical cognition.

Claims and statistical inference in animal physical cognition research.

Twenty years after Povinelli’s “Folk Physics for Apes”, this paper assesses how researchers have made claims about animal physical cognition, and the statistical inferences that have been used to support them. These data are relevant in light of the current replicability issues facing science. We surveyed 116 published experiments from 63 papers on physical cognition, which included data from 43 different species of animals. Across these experiments most sample sizes were small, with often fewer than 10 animals being tested. However, in contrast to related psychological disciplines, we found that only 62% of our sample of physical cognition research made positive claims. This suggests that animal physical cognition does not have a strong publication bias towards positive results. Furthermore, we found evidence that researchers are making many true statistical inferences at the individual level, i.e. whether individual animals pass certain tests of physical cognition or not. In contrast, the strength of evidence of statistical effects at the group level was weaker and consistent with many effect sizes being overestimated. Overall, our analysis provides a cautiously optimistic analysis of reliability and bias in animal physical cognition research, however it is nevertheless likely that a non-negligible proportion of results will be difficult to replicate.

Evidence of tool use in a seabird

Documenting novel cases of tool use in wild animals can inform our understanding of the evolutionary drivers of the behavior’s emergence in the natural world. We describe a previously unknown tool-use behavior for wild birds, so far only documented in the wild in primates and elephants. We observed 2 Atlantic puffins at their breeding colonies, one in Wales and the other in Iceland (the latter captured on camera), spontaneously using a small wooden stick to scratch their bodies. The importance of these observations is 3-fold. First, while to date only a single form of body-care-related tool use has been recorded in wild birds (anting), our finding shows that the wild avian tool-use repertoire is wider than previously thought and extends to contexts other than food extraction. Second, we expand the taxonomic breadth of tool use to include another group of birds, seabirds, and a different suborder (Lari). Third, our independent observations span a distance of more than 1,700 km, suggesting that occasional tool use may be widespread in this group, and that seabirds’ physical cognition may have been underestimated.