Anyone whose family includes a member of the canine species does not need to see a study to know the answer to this question! All you have to do is pay a little too much attention to your neighbor’s dog, and your pooch makes it perfectly clear in her own inimitable way that such behavior is not acceptable. And she can have a number of ways of showing her disapproval. Perhaps she nudges you with her nose or whines at you whenever you pet another animal. She may try to get in between you and her rival. She may even become overly protective of her food or toys in the presence of this interloper!
Dr. Christine Harris, Professor of Psychology at the University of California, San Diego and Caroline Prouvost, a student, performed a study on 36 small-breed dogs. They videotaped the dogs individually in their own homes, while their owners ignored them and lavished attention on two objects. The first was an animatronic dog which could bark, whine and wag its tail. The second was a plastic Jack-o-Lantern. The dog owners also read aloud from a pop-up book that played tunes. When the people showed affection to the fake dogs, 78% of the time, their dog would push or touch them. 30% of the time, they would try to get between their owner and the toy dog. 25% of the time, they would actually snap at the animatronic dog.
However, there were much less of these behaviors when their owners spoke sweetly to the toy pumpkin. 42% of the dogs tried to push or touch their owners, 15% tried to come between them, and only 1% snapped at the Jack-o-Lantern. There were also less jealous behaviors when the person read from the book. It seems the behaviors were triggered by signs of social interaction, such as the toy dog “responding” to their owner, rather than their owner ignoring them for an inanimate object. 86% of the dogs tried to sniff the butt of the toy dog during the experiment, which implies they thought it was real.
This experiment seems to indicate that when a dog sees its owner interact in an affectionate way with another animal, or what they perceive as another animal, they engage in behaviors that try to draw the affection back to them. However, not all scientists are willing to call it jealousy in the way that humans experience the emotion of jealousy. One scientist thought a more plausible explanation for the dogs’ behaviors in the experiment was that the dogs were showing interest because their owner was interacting with another “social being,” and they wanted to be part of the fun – not necessarily feeling the emotion of jealousy.
Many scientists believe animals are only capable of feeling less complex emotions such as anger and fear. In the case of jealousy, one has to have the cognitive ability to pay attention to how another individual is being rewarded, and then be able to compare it with one’s own treatment or rewards.
Dr. Harris and Ms. Prouvost concluded from their study that perhaps the emotion of jealousy is a more primordial emotion than previously thought. Such emotional responses have been noted in very young babies, and now it seems, in the canine species too.