Invertebrate animals are frequently lumped into a single category and denied welfare protections despite their considerable cognitive, behavioral, and evolutionary diversity. Some ethical and policy inroads have been made for cephalopod molluscs and crustaceans, but the vast majority of arthropods, including the insects, remain excluded from moral consideration. We argue that this exclusion is unwarranted given the existing evidence. Anachronistic readings of evolution, which view invertebrates as lower in the scala naturae, continue to influence public policy and common morality. The assumption that small brains are unlikely to support cognition or sentience likewise persists, despite growing evidence that arthropods have converged on cognitive functions comparable to those found in vertebrates. The exclusion of invertebrates is also motivated by cognitive-affective biases that covertly influence moral judgment, as well as a flawed balancing of scientific uncertainty against moral risk. All these factors shape moral attitudes toward basal vertebrates too, but they are particularly acute in the arthropod context. Moral consistency dictates that the same standards of evidence and risk management that justify policy protections for vertebrates also support extending moral consideration to certain invertebrates. Moving beyond a vertebrate-centered conception of welfare can also clarify foundational moral concepts in their own right.

Author Biography

Irina Mikhalevich, Assistant Professor of Philosophy, Rochester Institute of Technology, specializes in conceptual and methodological problems in comparative cognition science and their implications for the treatment of nonhuman animals. Website

Russell Powell, Associate Professor of Philosophy, Boston University, specializes in philosophical problems in evolutionary biology and bioethics. Website





Article Thread

Mikhalevich, Irina and Powell, Russell (2020) Minds without spines: Evolutionarily inclusive animal ethics. Animal Sentience 29(1)

Levy, Neil (2020) It might not matter very much whether insects are conscious. Animal Sentience 29(2)

Figdor, Carrie (2020) Relationship between cognition and moral status needs overhaul. Animal Sentience 29(3)

Browning, Heather and Veit, Walter (2020) Improving invertebrate welfare. Animal Sentience 29(4)

Vonk, Jennifer (2020) No room for speciesism in welfare considerations. Animal Sentience 29(5)

Cammaerts, Marie-Claire (2020) Invertebrates should be given ethical consideration. Animal Sentience 29(6)

Soryl, Asher (2020) Invertebrate welfare in the wild. Animal Sentience 29(7)

Monsó, Susana and Osuna-Mascaró, Antonio J. (2020) Problems with basing insect ethics on individuals’ welfare. Animal Sentience 29(8)

Balcombe, Jonathan (2020) Intuition and the invertebrate dogma. Animal Sentience 29(9)

Elwood, Robert W. (2020) Do arthropods respond to noxious stimuli purely by reflex?. Animal Sentience 29(10)

Zentall, Thomas R. (2020) Cognition, movement and morality. Animal Sentience 29(11)

Lockwood, Jeffrey A. (2020) Virtue ethics and the likelihood of invertebrate suffering. Animal Sentience 29(12)

Veit, Walter and Huebner, Bryce (2020) Drawing the boundaries of animal sentience. Animal Sentience 29(13)

Mallatt, Jon and Feinberg, Todd E. (2020) Sentience in evolutionary context. Animal Sentience 29(14)

DeGrazia, David (2020) On the possibility of invertebrate sentience. Animal Sentience 29(15)

Woodruff, Michael L. (2020) Whether invertebrates are sentient matters to bioethics and science policy. Animal Sentience 29(16)

Baracchi, David and Baciadonna, Luigi (2020) Insect sentience and the rise of a new inclusive ethics. Animal Sentience 29(18)

Marino, Lori (2020) Sentience in all organisms with centralized nervous systems. Animal Sentience 29(19)

Lee, Andrew Y. (2020) Does sentience come in degrees?. Animal Sentience 29(20)

Howard, Scarlett R. and Symonds, Matthew R.E. (2020) Ethical considerations for invertebrates. Animal Sentience 29(21)

Marzluff, John M. (2020) Bridging the empathy gap for invertebrates. Animal Sentience 29(22)

Dietrich, Eric and Fox Hall, Tara (2020) Moral treatment for all. Animal Sentience 29(23)

Key, Brian and Brown, Deborah (2020) Minds, morality and midgies. Animal Sentience 29(24)

Brown, Culum, Prof. (2020) Convergent evolution of sentience?. Animal Sentience 29(25)

Chapouthier, Georges (2020) Invertebrate cognition, sentience and biology. Animal Sentience 29(26)

Broom, Donald M (2020) Brain complexity, sentience and welfare. Animal Sentience 29(27)

Birch, Jonathan (2020) Zones of precaution. Animal Sentience 29(28)

Fitzpatrick, Simon (2020) Avoiding anthropocentrism in evolutionarily inclusive ethics. Animal Sentience 29(29)

Forber, Patrick and Jones, Robert C (2020) Spineless and sentient: a challenge for moral comparison. Animal Sentience 29(30)

Cartmill, Matt (2020) Do beetles have experiences? How can we tell?. Animal Sentience 29(31)

Delon, Nicolas; Cook, Peter; Bauer, Gordon; and Harley, Heidi (2020) Consider the agent in the arthropod. Animal Sentience 29(32)

Clarke, Steve (2020) When some animals are more equal than others. Animal Sentience 29(33)

Gibbons, Matilda and Sarlak, Sajedeh (2020) Inhibition of pain or response to injury in invertebrates and vertebrates. Animal Sentience 29(34)

Powell, Russell and Mikhalevich, Irina (2020) Affective sentience and moral protection. Animal Sentience 29(35)