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

Abstract

We know that even young children are proficient tool users, but until recently, little was known about how they make tools. Here, we will explore the concepts underlying tool making, and the kinds of information and putative cognitive abilities required for children to manufacture novel tools. We will review the evidence for novel tool manufacture from the comparative literature and present a growing body of data from children suggesting that innovation of the solution to a problem by making a tool is a much more challenging task than previously thought. Children's difficulty with these kinds of tasks does not seem to be explained by perseveration with unmodified tools, difficulty with switching to alternative strategies, task pragmatics or issues with permission. Rather, making novel tools (without having seen an example of the required tool within the context of the task) appears to be hard, because it is an example of an ‘ill-structured problem’. In this type of ill-structured problem, the starting conditions and end goal are known, but the transformations and/or actions required to get from one to the other are not specified. We will discuss the implications of these findings for understanding the development of problem-solving in humans and other animals.

The effects of environment and ownership on children's innovation of tools and tool material selection

“…This finding has been found to be consistent cross-culturally, both in WEIRD (Western, Educated, Industrialized, Rich and Democratic) societies and with a remote tribe of South African Bushman, and has been replicated with more simple tasks [13,14,16,18].…”

“…The foundation of tool use is the ability to create and invent tools, which evidently performed a vital role in human evolution [6,12,13]. Studying children, whose capabilities are still developing, allows insights into the psychological processes supporting tool-making and the age at which specific tool-making skills develop [14].…”

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

“…Such re-use of tools may facilitate learning of how to use these tools and what kind of tool features may be required for the task, especially when visual feedback is minimal [27,44,101,102]. Indeed, individuals master tool use, often if not always, before mastering tool manufacture [9,42,44,72,103]. Laboratory work supports the social enhancement of objects used as tools: for example, young New Caledonian crows and capuchins showed a preference for handling objects or tools that had been manipulated by demonstrator individuals [8,104].…”

“…High-fidelity action copying may provide human children with an alternative and quick route to obtain a material culture [111,112]. In fact, human children are rarely successful at making functional tools without a demonstrator until they are age 7 or older [72]. Although captive studies on apes do suggest that apes are capable of using both sources of information, results are mixed (see [113] for a review) and it is hard to know from observational studies what aspect of the action is attended to and affects learning, that is action imitation or observational learning of object affordances.…”

“…The errors described in the previous section may indicate an inability to inhibit such actions. Work in the laboratory shows that inhibiting so-called 'pre-potent' responses can indeed be a significant hurdle to problem solving in immature humans and mature primates (but see [72]). For example, chimpanzees performance on trap problems reveals that using a tool to rake-in the reward is easier for them than using a tool to push it away, in which they are less successful (see [73] for a review).…”