The soft‐bodied cephalopods including octopus, cuttlefish, and squid are broadly considered to be the most cognitively advanced group of invertebrates. Previous research has demonstrated that these large‐brained molluscs possess a suite of cognitive attributes that are comparable to those found in some vertebrates, including highly developed perception, learning, and memory abilities. Cephalopods are also renowned for performing sophisticated feats of flexible behaviour, which have led to claims of complex cognition such as causal reasoning, future planning, and mental attribution. Hypotheses to explain why complex cognition might have emerged in cephalopods suggest that a combination of predation, foraging, and competitive pressures are likely to have driven cognitive complexity in this group of animals. Currently, it is difficult to gauge the extent to which cephalopod behaviours are underpinned by complex cognition because many of the recent claims are largely based on anecdotal evidence. In this review, we provide a general overview of cephalopod cognition with a particular focus on the cognitive attributes that are thought to be prerequisites for more complex cognitive abilities. We then discuss different types of behavioural flexibility exhibited by cephalopods and, using examples from other taxa, highlight that behavioural flexibility could be explained by putatively simpler mechanisms. Consequently, behavioural flexibility should not be used as evidence of complex cognition. Fortunately, the field of comparative cognition centres on designing methods to pinpoint the underlying mechanisms that drive behaviours. To illustrate the utility of the methods developed in comparative cognition research, we provide a series of experimental designs aimed at distinguishing between complex cognition and simpler alternative explanations. Finally, we discuss the advantages of using cephalopods to develop a more comprehensive reconstruction of cognitive evolution.

中文翻译：

---

头足类动物有多聪明？比较认知的教训

包括章鱼、墨鱼和鱿鱼在内的软体头足类动物被广泛认为是认知能力最高的无脊椎动物群体。先前的研究表明，这些大脑软体动物具有一套与某些脊椎动物相似的认知属性，包括高度发达的感知、学习和记忆能力。头足类动物也以灵活行为的复杂技艺而闻名，这导致人们声称具有复杂的认知能力，例如因果推理、未来规划和心理归因。解释为什么头足类动物会出现复杂认知的假设表明，捕食、觅食和竞争压力的结合可能推动了这组动物的认知复杂性。目前，很难衡量头足类动物的行为在多大程度上受到复杂认知的支持，因为最近的许多说法主要基于轶事证据。在这篇综述中，我们提供了头足类认知的一般概述，特别关注被认为是更复杂认知能力的先决条件的认知属性。然后，我们讨论头足类动物表现出的不同类型的行为灵活性，并使用来自其他分类群的例子，强调行为灵活性可以通过假定更简单的机制来解释。因此，行为灵活性不应被用作复杂认知的证据。幸运的是，比较认知领域的重点是设计方法以查明驱动行为的潜在机制。为了说明在比较认知研究中开发的方法的实用性，我们提供了一系列旨在区分复杂认知和更简单的替代解释的实验设计。最后，我们讨论了使用头足类动物开发更全面的认知进化重建的优势。