Assessing positive emotional states in non-human primates is an emerging area of welfare science that goes beyond the absence of suffering to evaluate genuine wellbeing and flourishing.
The shift from focusing only on the absence of suffering to actively promoting positive welfare states represents a significant advance in primate welfare science. Primates living in social groups with compatible companions, adequate space, cognitive enrichment, and positive human interactions show behavioral signatures of positive emotional states. These include high rates of play, voluntary approach to caregivers, and exploration of novel objects. Institutions that actively promote positive welfare rather than simply minimizing obvious suffering achieve better outcomes for both animal welfare and scientific validity of their research.