Can dogs feel jealousy?
Do our four-legged friends feel jealousy? Scientists are searching for answers and finding more evidence that dogs have more complex emotions than previously thought.
A quiet growl, a vigorous nudge with the muzzle – and the dog suddenly pushes itself between its owner and the strange four-legged friend being petted. Or between its owner and an acquaintance engaged in a lively conversation. Such scenes are likely familiar to many dog owners. As soon as attention is directed toward another dog or person, your four-legged friend pushes itself to the forefront, as if to say: "Pay attention to me! You're my human!"
But is jealousy actually behind such behavior? Can dogs experience this emotion in a way comparable to that of humans? Or are we interpreting human emotions into our pets, thus over-humanizing them?
A spectrum of emotions
Observed behaviors were often attributed to simple instincts or learned reactions rather than complex emotional states. For a long time, it was assumed that dogs lacked complex cognitive abilities—especially those necessary for emotions like jealousy. However, significant advances in recent animal cognition research are refuting such views and opening up a more nuanced understanding of the inner emotional lives of our four-legged friends.
Jealousy: A purely human emotion?
Today, it's clear that dogs experience a wide range of emotions that profoundly influence their behavior and well-being. These include joy, fear, anger, anxiety, love, stress, security, and insecurity. Joy is often expressed through tail wagging and playful barking, while emotions like fear and anxiety can manifest as excessive panting, avoidance behavior, or aggression.
What dogs want to tell us with their looks
A recent study from the University of Auckland in 2021 also shows that dogs don't just react to visible rivals: The four-legged friends also show typical jealousy reactions when they merely suspect their owner is petting another dog – even if they can't see the scene. This suggests that dogs not only react to immediate visual stimuli but can also mentally represent jealousy-inducing situations. This ability was previously attributed primarily to human children.
Children and Dogs: A Developmental Analogy
In fact, researchers often compare dog emotional development to human development to understand dogs' emotional range. The consensus is that a dog's mind is roughly equivalent to that of a human child between 2 and 2.5 years old in terms of most mental abilities, including emotions. This means that dogs possess all basic emotions such as joy and love, fear, anger, and disgust.
However, this comparison also has limitations: More complex social emotions such as guilt, pride, and shame, which typically emerge later in human development (after the age of three for shame and pride, and even later for guilt), are generally not attributed to dogs. Behaviors often interpreted as guilt (for example, cowering after a "mishap") are more accurately understood as fear of punishment due to past experiences. While the analogy to a 2- to 2.5-year-old child helps understand basic emotions in dogs, denying certain complex emotions to four-legged friends is equally crucial.
Dog behavior: jealousy or resource protection?
Most scientists, therefore, assume that dogs do display behaviors reminiscent of jealous humans in some situations. However, scientists refer to a "primordial" form of jealousy in dogs rather than attributing the cognitively complex human emotion to them. This "core" form of jealousy can be triggered by relatively simple perceptions in dogs, for example, when dogs notice that their owner's attention has been captured by a potential rival.
From an evolutionary perspective, jealousy's negatively charged emotion can offer advantages, such as protecting social bonds or resources. Assuming that this function of jealousy is universal provides a theoretical basis for the possibility that jealousy also occurs in other social species, such as dogs, for whom strong social bonds with humans or their conspecifics were and still are crucial for their well-being and survival.
Nevertheless, even with the current research, it is impossible to prove whether dogs actually experience jealousy like humans. Although scientists can observe behaviors and draw valid conclusions based on biochemical processes, direct access to dogs' emotions is impossible. The focus, therefore, shifts to whether the observed behaviors in dogs are clear signs of jealousy and whether they meet its functional definition.
This means that even if dogs don't "feel" jealousy exactly like we humans do, their behavioral reactions still serve the same adaptive purpose, which is, in turn, scientifically objectively measurable. And that our four-legged friends feel emotions like anger or insecurity. Thanks to new research, we're gradually getting a better idea of what's going on in our dogs' minds. And this will help us better understand our four-legged friends in the future.