If at first you don't succeed… Studies of ontogeny shed light on the cognitive demands of habitual tool use

Abstract

Many species use tools, but the mechanisms underpinning the behaviour differ between species and even among individuals within species, depending on the variants performed. When considering tool use ‘as adaptation’, an important first step is to understand the contribution made by fixed phenotypes as compared to flexible mechanisms, for instance learning. Social learning of tool use is sometimes inferred based on variation between populations of the same species but this approach is questionable. Specifically, alternative explanations cannot be ruled out because population differences are also driven by genetic and/or environmental factors. To better understand the mechanisms underlying routine but non-universal (i.e. habitual) tool use, we suggest focusing on the ontogeny of tool use and individual variation within populations. For example, if tool-using competence emerges late during ontogeny and improves with practice or varies with exposure to social cues, then a role for learning can be inferred. Experimental studies help identify the cognitive and developmental mechanisms used when tools are used to solve problems. The mechanisms underlying the route to tool-use acquisition have important consequences for our understanding of the accumulation in technological skill complexity over the life course of an individual, across generations and over evolutionary time.

Tool use by aquatic animals

“…Like archerfish, sea otters also improve their tool use performance with experience [91]. In fact, sea otters appear to learn to use tools primarily through vertical social transmission, with pups adopting the same techniques, tools and diet as their mothers [91][92][93].…”

“…In Florida Bay, only bottlenose dolphins that use shallow sand banks engage in mud-ring feeding [40], and in Shark Bay, many dolphins that inhabit the same channels as spongers do not sponge forage [4]. Those dolphins that do adopt sponging learn the behaviour from their mothers and then almost exclusively forage using sponge tools throughout their lives, showing extensive lifetime learning with a peak in efficiency at mid-adulthood [74,93,94]. However, not all dolphins born to spongers adopt the behaviour even though both sexes are philopatric [95].…”

“…On land, when tool use requires learning, it is often associated with social tolerance, prolonged development and relatively larger brain size or elaborated cognition within taxa ( [85,93,98,99] although see Haslam [100]), but because of the scarcity of data in aquatic habitats, systematic phylogenetic comparisons are not yet possible (but see [70]). However, generally more cognitively complex tool use is characterized by tool manufacture [101], tool composites [102], tool re-use [102], cultural transmission [103] and cumulative technologies [86].…”

The development of tool manufacture in humans: what helps young children make innovative tools?

“…However, the process of making tools-particularly novel toolsremains somewhat mysterious in both humans and non-humans. For example, while we know that some non-human animals can manufacture tools [3,[5][6][7][8][9][10], the cognitive capabilities required to support this behaviour and the way in which it develops [11][12][13][14][15] are unclear. Even in humans, we know remarkably little about how tool making develops.…”

Perspectives on object manipulation and action grammar for percussive actions in primates

“…Efficient coping strategies to deal with errors appeared later in their lives, which suggests that these may be gradually acquired after long-term interaction with the objects and the achievement of an efficient level of skill [16,44]. Future studies are needed in order to accumulate more observational and developmental data, as not so many cases of wedgestone use have been reported in chimpanzees, and the actual process of making wedges has not been reported elsewhere.…”