Secondary emotions in non-primate species? Behavioural reports and subjective claims by animal owners

A defining characteristic of primary emotions is that they occur in wide variety of species. Secondary emotions are thought to be restricted to humans and other primates. We report evidence from two studies investigating claims of primary and secondary emotions in non-primate species. Study 1. We surveyed 907 owners about emotions that they had observed in their animal. Participants reported primary emotions more frequently than secondary emotions and self-conscious emotions more frequently than self-conscious evaluative emotions. Jealousy was reported at very high levels (81% of dogs and 79% of horses), which was surprising as jealousy is generally defined as a secondary emotion. Study 2. Forty dog owners were interviewed about the contexts and behaviours that led them to claim their animal was jealous. There was coherence and consistency in the behavioural descriptions of jealousy. We claim that such reports provide evidence for the existence of secondary emotions in non-primate species as predicted by theorists such as Buck (1999).