Recent research has transformed scientific understanding of fish cognition, establishing capabilities previously thought unique to mammals that have significant welfare implications.
The cognitive advances documented in fish research require updating our moral consideration of these animals. Fish that can recognize faces, learn from conspecifics, use tools, and show emotional states are not the simple reflex organisms once assumed. The welfare implications are profound: billions of fish are caught, farmed, and killed annually with essentially no welfare consideration. The gap between what science now tells us about fish inner lives and how we treat them in practice is one of the largest unaddressed welfare failures in history.