The question of invertebrate sentience is among the most contested in animal welfare science. Recent evidence has shifted expert opinion and policy in important ways.
The expansion of sentience recognition to invertebrates is one of the most significant shifts in animal welfare science and policy of recent decades. If even insects have some form of morally relevant experience, the scale of potential suffering in agriculture, pest control, and environmental degradation increases by orders of magnitude. Policy has begun to catch up to the science in the UK and EU, but most of the world has not yet incorporated invertebrate welfare into legal frameworks. This is a rapidly evolving area where evidence should drive policy.