Animal welfare
The field of moral and practical concern with how humans treat other sentient creatures, encompassing everything from factory farming and laboratory testing to wildlife conservation and companion-animal care. The modern movement traces its philosophical lineage to Jeremy Bentham's nineteenth-century observation that the relevant question about animals is not whether they can reason but whether they can suffer, and was given its contemporary utilitarian formulation by Peter Singer in Animal Liberation (1975). A persistent puzzle in the field is the gap between people's sympathies and their habits: charismatic megafauna like whales, elephants, and great apes attract intense protective feeling, while the vastly larger suffering imposed on farmed pigs, chickens, and fish receives comparatively little attention. More recent strands — including effective altruism's focus on shrimp and insect welfare — push the boundary further, arguing that moral weight should track sentience and scale rather than cultural salience.