Dog owners were right all along. Our pups really do get jealous when we direct our affection elsewhere—but mostly when their rival for attention appears to threaten their social life.
Once thought to be too complex an emotion for nonhumans, jealousy in canines—and the “pay attention to me” behaviors that arise from it—probably evolved to protect important social bonds in the pack, according to a new paper.An older dog looks out the window at the new member of the household. Photograph by Laura Humes, National Geographic Your Shot
Study leader Christine Harris, a psychologist at the University of California at San Diego, was playing with her parents’ border collies when she got the idea to study jealousy in dogs. (Read “Animal Minds” in National Geographic magazine.)
“I noticed that when I was paying attention to two of them at the same time, petting them and talking to them, they weren’t content to share that attention,” she said.
“One would push the other’s head out from underneath my hand so that both hands were on him. The other did the same. They each wanted exclusive affection.”
Sniffing Out Rivals
Adapting a jealousy study used on 6-month-old human babies, Harris and colleague Caroline Prouvost set up experiments with 36 dogs in their homes. The team videotaped the dogs’ reactions while their owners ignored them and instead paid attention to a stuffed animal (a realistic-looking dog that whined, barked, and wagged its tail), a jack-o-lantern pail, and a pop-up book that they read aloud.
The resulting behaviors suggest the dogs assessed each “rival” and decided whether it warranted action. If it did, they did their best to break the bond that left them out, according to the new study published July 23 in the journal PLOS ONE.
More specifically, of the 36 dogs observed—a varied lot including a Boston terrier, Yorkshire terriers, chihuahuas, a pug, and mutts—78 percent would push or touch the owner when that person was petting and sweet-talking the fake dog; 42 percent were upset over attention toward the pumpkin pail, and just 22 percent were bothered when the book was the focus. (See National Geographic’s dog pictures.)
Also telling, nearly a third of the dogs tried to place their bodies between the owner and the stuffed dog, and 25 percent snapped at the toy. (Only one dog snapped at the pail and book.) And 86 percent of the dogs sniffed the stuffed animal’s rear end as they would a real dog. It appeared, the scientists say, that the dogs saw the doglike interloper as a true threat.
That was a bit of a surprise. “We weren’t sure we would get such behaviors over a stuffed animal,” since it lacked the animation and smells of a real dog, Harris said. (Watch video: “Reading a Dog’s Signals.”)
“I think their reactions would have been even stronger had the rival been real.” (Including real rival dogs in the experiment would have muddied the findings, as it would be difficult to control the situation and collect data evenly.)
“Our research suggests that when confronted with a rival for a loved one’s attention, dogs engage in behaviors aimed at regaining the rival’s affection and getting rid of the rival.
“These behaviors would seem to be motivated from a jealous emotional state”—though of course, she pointed out, the findings don’t speak to the subjective state of the dog’s mind.
Dogs: Just Like Us?
So do dogs go green with envy in the same way we do? Probably not.
“Humans and dogs are different in a number of ways,” Harris said. “For example, I would doubt that the dog ruminates on the transgression after the fact, whereas humans do. Humans also ask themselves all kinds of questions about the meaning of an infidelity (am I boring? unlovable?) and about the relationship (will this be the end of my relationship?). These types of thoughts are obviously going to impact the experience and feelings of jealousy.”
Instead, what she imagines is shared across both species “is the urge to stop the interaction, to engage in behaviors that reestablish the loved one’s attention. The appraisal that a loved one is interacting with a rival seems sufficient to motivate this state.” (Take National Geographic’s dog quiz.)
The findings “are another step in dispelling myths about what dogs supposedly cannot do,” said Marc Bekoff, a fellow at the Animal Behavior Society and an expert in dog behavior.
There are compelling reasons based on solid evolutionary theory that even complex emotions like envy and guilt aren’t exclusive to human beings, said Bekoff, who wasn’t involved in the study.
“And there is no reason to assume that what animals experience is any less real or deep for them than our emotions are for us.”
It’s perhaps not surprising that in the study of human infants this dog study emulated, the babies, like the dogs, were much more likely to exhibit jealous behaviors when their mothers were attending to a realistic doll than when reading a book—a nonsocial activity.
More Green-Eyed Monsters?
Not only does the study show more broadly that jealousy is not a human construct, it also suggests the emotion does not have to be based on sexual rivalry—which is the way people often think about it.
Instead, it may have its roots in the need to secure resources in all kinds of valued social relationships, be they sexual, parental, sibling, or just friendly. (See “Q&A: What Can Dog Brains Tell Us About Humans?“)
Dogs seem like the perfect species in which to look for something like envy: They are cognitively sophisticated, form bonds with humans and with each other, and will try to manipulate the way we give them attention (as the collies did). But what about other animals?
The official studies still need to be done, but Bekoff said to expect a lot more evidence showing how sophisticated the emotional lives of nonhuman creatures can be.
“We need to keep the door open on the cognitive and moral capacities of other animals.”
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