New Caledonian crows keep 'valuable' hooked tools safer than basic non-hooked tools.
New Caledonian crows keep 'valuable' hooked tools safer than basic non-hooked tools.
复制标题
作者：
Klump BC;St Clair JJ;Rutz C
工具的临时存放和重复使用可以显着提高觅食效率。我们的一个研究群体中的新喀里多尼亚乌鸦使用两种类型的棒状工具——有钩的和无钩的——它们在原材料、制造成本和觅食性能方面有所不同。我们使用大量野生捕获、临时圈养的新喀里多尼亚乌鸦样本，通过实验研究了个体在有选择的情况下是否更喜欢一种工具类型，以及它们是否在连续使用期间更好地照顾自己喜欢的工具，将它们安全地存放在脚下或附近的洞里。与非钩状棒状工具相比，乌鸦更喜欢由绿花茎制成的带钩状棒状工具。重要的是，这种偏好也反映在随后的工具处理行为中，与来自落叶的非钩状棒状工具相比，受试者更经常保持钩状棒状工具的安全。这些结果表明，乌鸦“看重”带钩的棍状工具，与非钩状的棍状工具相比，这些工具的采购成本更高，使用效率更高。一系列对照治疗的结果表明，乌鸦会根据工具类型和原材料等多种因素改变其工具“保管”行为。据我们所知，我们的研究是第一个使用保管行为作为评估非人类动物如何评价不同工具类型的代理，为有效的跨分类比较建立了一个新的范式。
The temporary storage and re-use of tools can significantly enhance foraging efficiency. New Caledonian crows in one of our study populations use two types of stick tools – hooked and non-hooked – which differ in raw material, manufacture costs, and foraging performance. Using a large sample of wild-caught, temporarily captive New Caledonian crows, we investigated experimentally whether individuals prefer one tool type over the other when given a choice and whether they take better care of their preferred tools between successive episodes of use, safely storing them underfoot or in nearby holes. Crows strongly preferred hooked stick tools made from Desmanthus virgatus stems over non-hooked stick tools. Importantly, this preference was also reflected in subsequent tool-handling behaviour, with subjects keeping hooked stick tools safe more often than non-hooked stick tools sourced from leaf litter. These results suggest that crows ‘value’ hooked stick tools, which are both costlier to procure and more efficient to use, more than non-hooked stick tools. Results from a series of control treatments suggested that crows altered their tool ‘safekeeping’ behaviour in response to a combination of factors, including tool type and raw material. To our knowledge, our study is the first to use safekeeping behaviour as a proxy for assessing how non-human animals value different tool types, establishing a novel paradigm for productive cross-taxonomic comparisons.
DOI：
10.1111/bij.12757
发表时间：
2016-06
期刊：
Biological journal of the Linnean Society. Linnean Society of London
影响因子：
--
作者：
St Clair JJ;Klump BC;van der Wal JE;Sugasawa S;Rutz C
通讯作者：
Rutz C