Research into fish cognition has revealed capacities for learning, memory, and potentially social intelligence that have direct implications for how their welfare should be evaluated and protected.
Fish cognition research has progressively expanded the range of capacities documented in fish species, making simpler dismissals of fish intelligence increasingly untenable. The welfare implications of cognitive sophistication are direct: more cognitively complex animals can suffer more ways, are more affected by environmental impoverishment, and deserve greater moral consideration. The cumulative evidence from cognition research — learning, memory, social intelligence, possible self-awareness — strengthens the already-substantial welfare case from pain science.