There are few forces on Earth as pure as a dog’s love for its owner. The domestication of wolves (which may have begun in this cave) transformed later generations of canine, turning them from aggressive predators into bundles of human-loving joy (apart from Prancer). Our four-legged friends now come in a rich variety of shapes and sizes, but regardless of breed or pedigree, they are united in their love for their humans. Often among human relationships love can lead to jealousy, and a new study published in the journal Psychological Science may have demonstrated the same is true of dogs.
While it’s not all that pleasant when you get a case of the Green-Eyed Monster, jealousy is thought to be a social behavior that preserves valuable social bonds by protecting them from interlopers. It’s easily observed and interpreted when working with humans (who, crucially, speak) but there’s been little research into the jealous behaviors of dogs, or if they even get jealous at all. If owners are to be believed, then there's plenty of anecdotal evidence (who doesn't want to think their dog is special), but little in the way of hard evidence beyond this betrayed beagle whose owner is stroking other dogs on Red Dead Redemption.
To find out, the study asked people to bring their dedicated doggos along to partake in an experiment which saw the dogs watch a video of their human interacting with two objects: a fleece cylinder or a fake dog. It was decided that pulling on the leash would be indicative of the dog’s jealousy, as a similar behavior is observed in jealous children.
“The single most consistent jealous behavior that we see in infants is an approach response as they try to disrupt their mother’s interaction with a rival,” said Amalia Bastos from The University of Auckland in the below video about the research. “So, we were interested to see if dogs would show this as well, pulling harder when they were faced with a jealousy-inducing situation.
The video showed the dogs' owners stroking the objects in different conditions to ascertain if the dogs responded to an inanimate object (the fleece cylinder) in the same way as a perceived rival (the fake pup). Not only did the dogs get more jealous when the owner was stroking the fake dog (a potential rival), they even got jealous when a screen was put up obscuring the view. In this condition, the fake dog was not in view but that the owner was stroking something that was still visible to the dog. Their jealousy, despite having the rival obscured from view, indicates that whatever they thought was going on behind that barrier was something they weren’t on board with.
By comparison, the dogs had little interest in the conditions where the owner was stroking the fleece cylinder even though the fake dog was still in the room. “The fake dog was present in the room in every condition because we wanted to make sure the dogs weren’t pulling due to fear, aggression or interest towards the fake dog,” continued Bastos. “We can safely exclude these alternative hypotheses because dogs pulled more strongly only in jealousy-inducing situations.”
The observations can’t be considered irrefutable evidence for the jealousy of dogs, owing to the fact we can’t (yet) carry out a debrief to confirm their motivations. They do however show that dogs exhibit some of the same signatures of jealous behavior that humans show, increasing the likelihood that our actions are fueled by similar motivations. “The more behavioral signatures we can see in common between humans and other animals,” said Bastos, “the more certain we can be that their minds work in similar ways to ours.”