Cephalopods have the most complex nervous systems of any invertebrate and are increasingly recognised as welfare-relevant animals.
Cephalopods sit at the frontier of invertebrate welfare science. The evidence for complex cognition — play, problem-solving, curiosity, and apparent emotional states — is significantly stronger for octopuses than for almost any other invertebrate. The EU recognised this in extending research animal protection to cephalopods in 2010. The emerging question of octopus farming is particularly acute: animals with strong individual territory needs, complex sensory worlds, and apparent capacity for boredom and distress are very poorly suited to aquaculture conditions.