Contrasting findings made it unclear what cognitive processes New Caledonian crows use to procure suitable tools to solve tool tasks. Most previous studies suggested that their tool procurement is achieved by either trial and error or a simple heuristic. The latter provides a fast and cognitively efficient method for stable, routinized behaviour based on past experience with little or no deliberate decision-making. However, early papers by Chappell and Kacelnik reported that two New Caledonian crows procured tools after closely assessing the tool characteristics required for the task, thus using deliberate decision-making, or a ‘customized strategy’. Here, I tested eight New Caledonian crows to determine their default behaviour in basic tool procurement tasks as a check on whether or not they use customized strategies. I used two rigorous experiments closely based on Chappell and Kacelnik’s experiments. The crows did not use a customized strategy in either experiment, but their behaviour was clearly consistent with tool procurement predominantly guided by a familiarity heuristic. I discuss potential methodological issues that may have led to different conclusions in Chappell and Kacelnik’s studies. Heuristic-guided, routinized behaviour in tool procurement has potential implications for understanding how standardization occurs in the early evolution of complex tool manufacture, both in New Caledonian crows and early humans.

相反的结果使得人们不清楚新喀里多尼亚乌鸦使用什么认知过程来购买合适的工具来解决工具任务。以前的大多数研究表明，他们的工具采购是通过反复试验或简单的启发式方法来实现的。后者基于过去的经验，很少或没有经过深思熟虑的决策，为稳定，常规化的行为提供了一种快速而有效的认知方法。但是，Chappell和Kacelnik的早期论文报道说，两只新喀里多尼亚乌鸦在仔细评估任务所需的工具特征后购买了工具，因此使用了故意的决策或“定制策略”。在这里，我测试了八只新喀里多尼亚乌鸦，以确定它们在基本工具采购任务中的默认行为，以检查它们是否使用定制策略。我根据Chappell和Kacelnik的实验紧密地使用了两个严格的实验。在任何一个实验中，乌鸦都没有使用定制的策略，但是它们的行为显然与以熟悉度启发法为主导的工具采购相一致。我讨论了可能导致Chappell和Kacelnik的研究得出不同结论的潜在方法论问题。刀具采购中的启发式，常规化行为对于理解在新喀里多尼亚乌鸦和早期人类中复杂刀具制造的早期发展中标准化如何发生具有潜在的影响。我讨论了可能导致Chappell和Kacelnik的研究得出不同结论的潜在方法论问题。刀具采购中的启发式，常规化行为对于理解在新喀里多尼亚乌鸦和早期人类中复杂刀具制造的早期发展中标准化如何发生具有潜在的影响。我讨论了可能导致Chappell和Kacelnik的研究得出不同结论的潜在方法论问题。刀具采购中的启发式，常规化行为对于理解在新喀里多尼亚乌鸦和早期人类中复杂刀具制造的早期发展中标准化如何发生具有潜在的影响。