Mather’s call to consider cephalopods’ consciousness “on their own terms” raises the question of the extent to which cephalopods can be considered a homogenous group. While coloeoid cephalopods share traits that strongly distinguish them from other molluscs and invertebrates, they show vast ecological and morphological diversity, with implications for the design of empirical investigations of consciousness. Extending Mather’s argument, we apply Birch et al.’s (2020) five-dimensional model to compare octopus, cuttlefish, squid, and nautilus. This comparison shows that even within a graded rather than categorical framework, putative consciousness profiles depend on which taxa are included in discussions of “cephalopod consciousness.” The resulting uncertainty highlights that choosing a taxonomic level for discussing animal consciousness remains a central conceptual challenge.

Who is conscious and how do we know? Complexity in behavior and cognition is certainly a clue that cannot be ignored in identifying this trait, and as Mather’s target article shows, it is hard not to imagine consciousness arising in cephalopods. But how complex is complex? An alternative may be gleaned from the fact that all living things rely on negative feedback to navigate their worlds, and this requires all sentient beings knowing what is to be stabilized in reflection to themselves. If so, consciousness is a universal trait.

Mather presents comprehensive evidence of cephalopod cognitive ability and of a high level of awareness. The importance of taking account of the biological functioning and adaptations to the living environment is emphasised. An argument is presented that it is better to limit the use of the word conscious to ‘not unconscious’ and to use awareness in relation to the various levels of cognitive functioning.

Jennifer Mather has nicely summarized what is known about consciousness in shallow water octopods as well as what is known about shallow water squids and cuttlefish. However, once she gets below SCUBA depths, she misses out on most of cephalopod diversity. I have attempted to add this aspect and perhaps some evolutionary biology to this target article.

Jennifer Mather has provided a comprehensive and fascinating overview of the various cognitive accomplishments of cephalopods and their sensory, behavioral, and neurophysiological attributes. The advances in our understanding of a clade that has been separated from vertebrate evolution by well over half a billion years is a testament to advances in both methodology and the questions we now feel free to address. Mather embeds her review in the issue of consciousness, which is certainly a perennial issue in mental evolution, going back to Romanes and earlier. I argue that the term “consciousness” has such a checkered history and is used in such diverse ways even today that, despite current popular enthusiasm, it is scientifically misleading.

Oldfield & Bonano (2024) point out not only the scarcity of research on fish welfare but also significant taxonomic bias in broader research on these species. This bias extends to the management practices of aquaria and zoos, where the focus is on higher vertebrates. More resources need to be allocated to research to address this disparity. We also need to develop welfare constructs that recognize the inherent differences between aquatic and terrestrial species, taking into account the unique ecological contexts and behavioral patterns of fishes.

Oldfield & Bonano (2024) identify significant gaps in scientific knowledge about certain animal taxa, such as reptiles, amphibians, invertebrates, and fish. Despite some efforts, published literature remains limited, forcing decision-makers to rely more on experiential knowledge than scientific evidence. AZA-accredited zoos and aquariums are uniquely positioned to bridge these gaps and advance animal welfare science by fostering collaboration, building partnerships, and promoting multi-disciplinary approaches to welfare assessments.

Carolyn Ristau offers a stellar investigative biography of Donald Redfield Griffin and his influence on the science and philosophy of animal minds. This commentary focuses on his aim to study animal minds through an ethological lens—that is, by examining the evolved, adaptive functions of mental capacities and consciousness in natural environments, rather than confining research to controlled laboratory settings. I argue that, far from being romantic, this approach can be firmly grounded in modern life history theory.

Because cephalopods are so different from the vertebrate lineage, their possible consciousness must be assessed on the basis of their heritage and abilities. Cephalopods have evolved in water, a denser medium than air, and their perception is adapted to it. They have inherited the molluscan mantle cavity and hydrostatic muscle type, which has led to a more distributed motor control system despite a centralized brain, and have evolved a completely novel skin display system. Using these abilities, octopuses can form concepts, plan for the future, generate a cognitive map, and self-monitor for apparent pain and manipulate communication. Most cephalopods use the skin display system fairly automatically to deceive potential predators, although cuttlefish and squid also communicate with conspecifics. They do not appear to have the social sophistication to form a Theory of Mind when using it, but some squid can divorce the skin output from its motivational background sufficiently to produce two separately motivated displays in different directions at the same time. Thus, the cephalopods do appear to be moving towards consciousness, but on their own terms rather than our vertebrate terms.

Donald Griffin’s work revolutionized cognitive ethology and continues to challenge human exceptionalism by emphasizing rigorous, unbiased inquiry. His legacy calls for a deeper recognition of humanity’s place within the broader animal community, urging interdisciplinary approaches that bridge science, ethics, and cultural traditions to foster a more inclusive understanding of life.