You might think that a dog’s wagging tail is a pretty simple communication device—a wag is a wag. It probably means the dog’s happy. But, according to new research, the wag is a much more complicated form of communication. It turns out that if a dog is wagging its tail in one direction more than another, he might be telling you something.
Marcello Siniscalchi of the University of Bari Aldo Moro in Italy and colleagues decided to look at asymmetry in dog wags. They noticed that sometimes, dogs wag more to the right, usually when seeing their owner or something else happy. They wag more to the left when they see something like a dominant or unfamiliar dog. So the wag itself could represent the emotional state of the dog doing the wagging.
Being a scientist, Sinischalchi decided to do a study based on this observation. In the journal Current Biology, he reports that other dogs can in fact distinguish a right-leaning tail wag from a left-leaning tail wag. Not only can dogs tell the difference, they understand what it means. Dogs who saw left-wagging tails showed more stress than dogs who saw right-wagging tails. The authors hypothesize that it has to do with dogs having a “right brain” and “left brain”—much like people do (although not everyone is convinced of this hypothesis).
We can say for sure that dogs are attuned to the direction of their fellow dogs wagging. And understanding how dogs communicate could help people, too. Every little clue into what your dog is thinking helps you understand him that much better.
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