Understanding which animals can suffer is the foundation of animal welfare ethics. Sentience research is advancing rapidly, with implications for which species deserve moral consideration and what kinds of protection they need.
The question of which animals are sentient has direct welfare implications: sentient animals can suffer and their suffering matters morally. Sentience research informs both law (which species are protected) and practice (which farming or research methods require welfare standards). The precautionary principle — that we should protect species whose sentience is uncertain rather than wait for certainty before acting — is gaining ground in policy. The Sentience Institute advocates for a wide moral circle, recognising that historical expansions of moral concern have consistently been vindicated. For welfare practitioners, keeping up with sentience research means remaining open to updating which species and contexts require welfare consideration even as current knowledge evolves.