Dataset Information

Raw-material selectivity in hook-tool-crafting New Caledonian crows.

ABSTRACT: Animals that manufacture foraging tools face the challenge of identifying suitable raw materials among a multitude of options. New Caledonian crows exhibit strong population-specific material preferences for the manufacture of hooked stick tools, but it is unknown how they identify their favourite plants. We investigated experimentally whether crows pay attention to the stems of plants (from which the tools are made) and/or their leaves (which are usually discarded during manufacture but may enable rapid and reliable species identification at a distance). Subjects were highly selective in choice trials with multiple plant species. Two additional treatments with experimental leaf-stem combinations revealed that birds can identify their preferred plant species by its stems alone, and possibly also its leaves. These findings encourage future experiments that investigate whether New Caledonian crows attend to features of the stem that are required for the production of efficient hooked stick tools. Our study provides one of the most detailed assessments to date of how non-human animals identify raw materials for tool manufacture.

SUBMITTER: Klump BC

PROVIDER: S-EPMC6405461 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Raw-material selectivity in hook-tool-crafting New Caledonian crows.

Klump Barbara C BC Cantat Mathieu M Rutz Christian C

Biology letters 20190201 2

Animals that manufacture foraging tools face the challenge of identifying suitable raw materials among a multitude of options. New Caledonian crows exhibit strong population-specific material preferences for the manufacture of hooked stick tools, but it is unknown how they identify their favourite plants. We investigated experimentally whether crows pay attention to the stems of plants (from which the tools are made) and/or their leaves (which are usually discarded during manufacture but may ena ...[more]

PMID: 30958132

Similar Datasets

Project description:BackgroundUsing tools to act on non-food objects--for example, to make other tools--is considered to be a hallmark of human intelligence, and may have been a crucial step in our evolution. One form of this behaviour, 'sequential tool use', has been observed in a number of non-human primates and even in one bird, the New Caledonian crow (Corvus moneduloides). While sequential tool use has often been interpreted as evidence for advanced cognitive abilities, such as planning and analogical reasoning, the behaviour itself can be underpinned by a range of different cognitive mechanisms, which have never been explicitly examined. Here, we present experiments that not only demonstrate new tool-using capabilities in New Caledonian crows, but allow examination of the extent to which crows understand the physical interactions involved.Methodology/principal findingsIn two experiments, we tested seven captive New Caledonian crows in six tasks requiring the use of up to three different tools in a sequence to retrieve food. Our study incorporated several novel features: (i) we tested crows on a three-tool problem (subjects were required to use a tool to retrieve a second tool, then use the second tool to retrieve a third one, and finally use the third one to reach for food); (ii) we presented tasks of different complexity in random rather than progressive order; (iii) we included a number of control conditions to test whether tool retrieval was goal-directed; and (iv) we manipulated the subjects' pre-testing experience. Five subjects successfully used tools in a sequence (four from their first trial), and four subjects repeatedly solved the three-tool condition. Sequential tool use did not require, but was enhanced by, pre-training on each element in the sequence ('chaining'), an explanation that could not be ruled out in earlier studies. By analyzing tool choice, tool swapping and improvement over time, we show that successful subjects did not use a random probing strategy. However, we find no firm evidence to support previous claims that sequential tool use demonstrates analogical reasoning or human-like planning.Conclusions/significanceWhile the ability of subjects to use three tools in sequence reveals a competence beyond that observed in any other species, our study also emphasises the importance of parsimony in comparative cognitive science: seemingly intelligent behaviour can be achieved without the involvement of high-level mental faculties, and detailed analyses are necessary before accepting claims for complex cognitive abilities.

Dataset Information

Raw-material selectivity in hook-tool-crafting New Caledonian crows.

Publications

Raw-material selectivity in hook-tool-crafting New Caledonian crows.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets