Mantis shrimp and other crustaceans are showing increasingly complex behaviors that challenge assumptions about invertebrate sentience and complicate fisheries welfare ethics.
Crustacean sentience research has advanced rapidly, with studies demonstrating learned avoidance of harmful stimuli, trade-off behavior between safety and food that suggests pain as a cost, and physiological responses to injury similar to vertebrate pain systems. Mantis shrimp cognitive complexity adds to the evidence base. These findings are influencing legislation in multiple countries and should inform fishing and aquaculture practices that routinely involve live boiling and other potentially painful procedures.