If You Want to Know if Spot Loves You So, It’s in His Tail

If You Want to Know if Spot Loves You So, It’s in His Tail

By SANDRA BLAKESLEE



Center for Neurosci./Univ. Trieste

A Matter of Degree: Seeing its owner, the dog wagged harder to its right. Shown an unfamiliar dog, the bias was to the left.




Every dog lover knows how a pooch expresses its feelings.
Ears close to the head, tense posture, and tail straight out from the body means “don’t mess with me.” Ears perked up, wriggly body and vigorously wagging tail means “I am sooo happy to see you!”
But there is another, newly discovered, feature of dog body language that may surprise attentive pet owners and experts in canine behavior. When dogs feel fundamentally positive about something or someone, their tails wag more to the right side of their rumps. When they have negative feelings, their tail wagging is biased to the left.
A study describing the phenomenon, “Asymmetric tail-wagging responses by dogs to different emotive stimuli,” appeared in the March 20 issue of Current Biology. The authors are Giorgio Vallortigara, a neuroscientist at the University of Trieste in Italy, and two veterinarians, Angelo Quaranta and Marcello Siniscalchi, at the University of Bari, also in Italy.
“This is an intriguing observation,” said Richard J. Davidson, director of the Laboratory for Affective Neuroscience at the University of Wisconsin in Madison. It fits with a large body of research showing emotional asymmetry in the brain, he said.