

Originally published on July 30, 2014 10:47 am


Many if not all dog owners are sure that their pets have feelings. And we've known for a while that animals exhibit behaviors that look like jealousy, guilt and shame. But it's hard to find out what animals are really feeling. And researchers say that understanding that could give us valuable insights into human emotions, too.



The dogs seemed less jealous of the jack-o'-lantern. But 40 percent acted aggressive when their owners started talking to the plastic pumpkins.

Psychologist Christine Harris, who led the study, says she's been studying jealousy for many years — but in humans. "The motivation that you have when you're jealous is to really break up the liaison between your loved one and your rival," she told Shots.

The fact that these dogs seemed like they were trying to draw their owners away from the stuffed animal indicates that they're feeling something very similar to human jealousy, Harris says.

"This is really a landmark study," says Marc Bekoff, an emeritus professor of evolutionary biology at the University of Colorado in Boulder, and author of Why Dogs Hump and Bees Get Depressed. "It opens the door to a lot more research on animal emotion."

Bekoff, who wasn't involved in the research, says that he's definitely seen what looks like jealousy in his work with not only dogs but also coyotes and wolves. But this study is one of the first controlled experiments that tries to show it.

Of course, the study still doesn't prove that dogs feel jealousy. "The problem is that [the researchers] didn't look at how dogs would react just to those objects," says Laurie Santos, director of the Canine Cognition Center at Yale University.


But this study does build on previous research that shows dogs react negatively when they're treated unfairly, she tells Shots. "This is a very new science. We are just developing new tools to better understand animal emotions."

In humans, jealousy can be a very complex emotion, Santos says. It can bring up a host of other emotions like anger and rejection. And when humans feel jealous, we start suspecting and speculating, she says. "We think, 'If my husband is talking to another woman, maybe he's cheating.' "

If we find out that dogs feel the same way, she says, "either jealousy is less complicated because animals show it, or animals are more complicated than we thought."

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