Jealousy is not just a human condition according to researchers, as it appears in our faithful canine companians as well.
Scientists in California found that canines succumbed to the green eyed monster when their owners showed affection to a stuffed dog in tests.
Some experts have argued that jealousy requires complex cognition and is unique to people.
But the authors say their work shows it may also come in a more basic form.
These findings probably won’t be a major surprise to anyone who’s ever owned a dog, but the team say this is the first experimental test of jealous behaviours in man’s best friend.
Human jealousy is a complicated emotion, requiring a “social triangle” and usually arising when an interloper threatens an important relationship.
The scientists studied 36 dogs in their homes and video recorded their actions when their owners displayed affection to a realistic-looking stuffed canine.
Over three quarters of the dogs were likely to push or touch the owner when they interacted with the decoy.
The envious mutts were more than three times as likely to do this for interactions with the stuffed dog compared to when their owners gave their attention to other objects including a book.
Around a third tried to get between the owner and the faux fido, while a quarter of the put-upon pooches snapped at the dummy dog.
“Our study suggests not only that dogs do engage in what appear to be jealous behaviours but also that they were seeking to break up the connection between the owner and a seeming rival,” said Prof Christine Harris from University of California in San Diego.