Dogs Can Act Jealous, Study

Like humans, dogs also express jealousy when their owners spend more time with other dogs, a new study reveals.

For several years, there have been debates among emotion researchers whether jealousy requires a complex cognition. A few scientists even argue that jealousy is a social construct not present in all human cultures. But, psychology professor Christine Harris and former honors student Caroline Prouvost at the University of California claim that dogs can act jealous too.

The new study is the first experimental test of jealous behavior in dogs. The findings also state that there might be other forms of jealousy present among other species. The researchers noticed that a dog displays jealous behavior when its owner shows affection to another dog.

Their jealous behavior included snapping and pushing their owner or rival. The jealous behavior was displayed more if the owner showered affection on a new object as well as when the owner's attention was diverted by reading a book.

"Our study suggests not only that dogs do engage in what appear to be jealous behaviors but also that they were seeking to break up the connection between the owner and a seeming rival," Harris said. "We can't really speak to the dogs' subjective experiences, of course, but it looks as though they were motivated to protect an important social relationship."

Since no experiments have ever been conducted on dog jealousy, the current study researchers used a test that is done with six months old human babies.

The experiment included 36 dogs, whose behavior was video-taped at their homes when their owners ignored them in favor of a stuffed, animated dog or a jack-o-lantern pail. In both the settings, the owners were told to treat the novel object as though they were real and pet them and talk to them sweetly.

In the third setting, the owners were asked to read aloud a pop-up book that played melodies. The videos were then rated by two independent raters for a range of aggressive, disruptive and attention-seeking behavior.

They noticed that the dogs were two times more vulnerable to push or touch their owners when a faux dog was in place than when he was attending to the pail i.e. 78 percent versus 42 percent. The same behavior was displayed by 22 percent of the dogs when the owners were reading a book.

Does this mean that the dogs perceived the stuffed animals as real? According to the researchers, the aggression displayed by the dogs indicated that they did. This is supported by the evidence that 86 percent of the dogs sniffed the toy dog's rear during the experiment.

The researchers highlight that it is extremely crucial to understand jealousy as it is an emotion with far-reaching psychological and social consequences.

"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," Harris said. "Our results challenge these ideas, showing that animals besides ourselves display strong distress whenever a rival usurps a loved one's affection."

The finding was documented in the journal PLOS One.