Dogs display more jealous behavior (such as snapping) when their owner shows affection towards other canines as opposed to random objects.
The study, published in the July 23, 2014 in the open-access journal PLOS ONE, suggests dogs have the ability to feel the complex emotion of jealousy. Scientists usually look at jealousy as an emotion that requires complex cognition to experience. This finding suggests there may be a more basic form of jealousy that could exist in other species.
To make their findings researchers tested thirty-six dogs and videotaped them while their owners ignored them and interacted with either a realistic stuffed dog, jack-o-lantern, or book. The tests looked at whether or not the dogs' behavior indicated jealousy or simply negative feelings associated with the loss of attention. The dogs were monitored for behaviors such as "aggression, attention seeking, and/or interest in the owner or object."
The team found dogs exhibited significantly more jealous behavior when their owners showed affection to what they though was another dog than if they interacted with other objects. This means jealousy could exist in a primordial form that is also believed to exist in human infants. The finding suggests jealousy evolved to secure resources in both sexual relationships as well as other types of human bonds. This includes competing for parental resources such as "food, attention, care, and affection."
"Many people have assumed that jealousy is a social construction of human beings--or that it's an emotion specifically tied to sexual and romantic relationships. Our results challenge these ideas, showing that animals besides ourselves display strong distress whenever a rival usurps a loved one's affection," Christine Harris of UC San Diego said. Caroline Prouvost from UC San Diego was also a leader of the study.
