Do Dogs Experience Jealousy?
By Rachele Baker, DVM – Do dogs experience jealousy? Based on personal experience, I would say that the answer to this question is “yes.” I have witnessed it many times. For example, when I sit down and my cat starts rubbing up against my legs hoping to get petted, in less than five seconds my dog is pushing herself between my legs to get petted and using her nose to try to push the cat away from me.
But do dogs experience jealousy in the same way that humans do? That is an interesting question which was addressed in a study performed at the University of California in San Diego by Christine Harris and Caroline Prouvost. The results of their study were published in PLOS ONE.
When I read the study in PLOS ONE, I learned that jealousy is usually considered to be a “complex” emotion rather than a “basic” emotion. “Basic” emotions such as anger or fear occur automatically without much evaluation or cognitive processing. “Complex” emotions require the cognitive ability to understand and evaluate situations.
It has been commonly assumed that jealousy is a complex emotion requiring the cognitive ability to recognize that a potential rival may threaten an important relationship such as when a woman or man suspects that their partner is cheating on them. In this study, the researchers proposed that there may be an innate form of jealousy existing from birth that is provoked by a sense of threat to a valued relationship that does not require complex cognitive abilities or the ability to assess the potential rival’s threat to a relationship.
Studies in human infants have shown that infants experience an innate form of jealousy. A study performed at Texas Tech University found that six-month-old infants displayed negative facial expressions when their mothers interacted with lifelike dolls. In another study, eight-month-old infants attempted to distract their mothers when their mothers interacted with another child.
Harris and Prouvost speculated that it is possible that jealousy originated as a response to competition between siblings that are inherently rivals for their parents’ resources such as food and care. Interestingly, sibling rivalry is seen in species other than humans. For example, in a number of bird species, an older chick may kill its younger siblings if it is not receiving enough food to maintain its body weight.
The Study To Determine If Dogs Experience Jealousy
The study to determine if dogs experience jealousy at the University of California in San Diego was modeled after human infant studies of jealousy. Thirty-six dogs were individually videotaped while their owners interacted with three different objects: a stuffed toy dog which barked and wagged its tail, a jack-o-lantern pail, and a children’s musical pop-up book.
Observing the dogs’ behavior when their owners petted and talked sweetly to a stuffed toy dog and then did the same with a jack-o-lantern pail enabled the researchers to determine whether the dogs would display jealous behaviors only when their owners showed affection toward another animal or whether the dogs would display jealous behaviors when their owners displayed affection toward an object of any kind.
Observing the dogs’ behaviors when their owners read a children’s book out loud allowed the researchers to determine whether the dogs’ reactions were simply due to the loss of their owners’ attention or if their reactions were due to a sense of threat to a valued relationship.
In order to determine if the dogs in the study perceived the stuffed toy dog as a real dog, the researchers noted whether the dogs sniffed the rear end of the stuffed toy dog. It was noted that the vast majority of the dogs in the study, eighty-six percent, sniffed the anal region of the stuffed toy dog.
For purposes of the study to determine if dogs experience jealousy, the dogs’ owners were instructed to interact with the stuffed toy dog as if they were playing with a real dog and to completely ignore their dog for the duration of the interaction. The stuffed toy dog barked, whined, and wagged its tail when a button on the top of its head was pressed.
For the second part of the study, the dogs’ owners were instructed to interact in the same manner with a jack-o-lantern pail and to act like they were playing with a real dog when interacting with the jack-o-lantern pail.
For the third part of the study, the dogs’ owners were instructed to read aloud a children’s musical pop-up book.
Twenty-five percent of the dogs snapped at the stuffed toy dog when their owners were interacting with it but only one dog snapped at the jack-o-lantern pail and book when his owner was interacting with those objects. Dogs were significantly more likely to push or touch their owners and the stuffed toy dog when their owners interacted with the stuffed toy dog than when their owners interacted with the jack-o-lantern pail or book. Dogs tried to get between their owners and the stuffed toy dog more frequently than between their owners and either the jack-o-lantern pail or the book. Whining occurred significantly more when the dogs’ owners were interacting with the stuffed toy dog than when the owners were reading a book out loud.
In human infant studies, signs of jealousy included increased attention toward the mother when she was interacting with what appeared to be another infant. The researchers in the dog study observed similar behaviors in the dogs when their owners were displaying affection toward the stuffed toy dog or the jack-o-lantern pail.
The results of this study suggest that an innate form of jealousy is experienced by dogs when their owner’s attention is directed towards a potential rival. In the face of a potential threat to their relationship with their owner, a large proportion of dogs will attempt to regain their owner’s attention and block or remove the potential rival.