Left or right wagging tail means different things among dogs
There is more to the dog wagging its tail than meets the eye,
scientists have found. The rightward wag and the leftward wag mean
different things to dogs. This happens because dogs, like humans, have
asymmetrically organized brains, with the left and right sides playing
different roles, thescientific study published in the journal Current
Biology on Thursday, suggests.
The Italian research team led by Giorgio Vallortigara of the Center for Mind/Brain Sciences of the University of Trento had earlier found that dogs wag to the right when they feel positive emotions (upon seeing their owners, for instance) and to the left when they feel negative emotions (upon seeing an unfriendly dog, for example). That biased tail-wagging behavior reflects what is happening in the dogs' brains. Left-brain activation produces a wag to the right, and right-brain activation produces a wag to the left.
But does that tail-wagging difference mean something to other dogs? Yes it does, the new study shows.
While monitoring their reactions, the researchers showed dogs videos of other dogs with either left- or right-asymmetric tail wagging. When dogs saw another dog wagging to the left, their heart rates picked up and they began to look anxious. When dogs saw another dog wagging to the right, they stayed perfectly relaxed.
"The direction of tail wagging does in fact matter, and it matters in a way that matches hemispheric activation," says Vallortigara.
A right wag means the left hemisphere of the brain is activated in the dog. That means it is experiencing some positive response. So, another dog observing it would feel a relaxed response. In contrast, a dog showing a left wag activated by the right hemisphere is feeling a negative or withdrawal response. To the observing dog, this would induce an anxious and targeting response as well as increased cardiac frequency.
Vallortigara doesn't think that the dogs are necessarily intending to communicate those emotions to other dogs. Rather, he says, the bias in tail wagging is likely the automatic byproduct of differential activation of the left versus the right side of the brain. But that's not to say that the bias in wagging and its response might not find practical uses; veterinarians and dog owners might do well to take note.
The Italian research team led by Giorgio Vallortigara of the Center for Mind/Brain Sciences of the University of Trento had earlier found that dogs wag to the right when they feel positive emotions (upon seeing their owners, for instance) and to the left when they feel negative emotions (upon seeing an unfriendly dog, for example). That biased tail-wagging behavior reflects what is happening in the dogs' brains. Left-brain activation produces a wag to the right, and right-brain activation produces a wag to the left.
But does that tail-wagging difference mean something to other dogs? Yes it does, the new study shows.
While monitoring their reactions, the researchers showed dogs videos of other dogs with either left- or right-asymmetric tail wagging. When dogs saw another dog wagging to the left, their heart rates picked up and they began to look anxious. When dogs saw another dog wagging to the right, they stayed perfectly relaxed.
"The direction of tail wagging does in fact matter, and it matters in a way that matches hemispheric activation," says Vallortigara.
A right wag means the left hemisphere of the brain is activated in the dog. That means it is experiencing some positive response. So, another dog observing it would feel a relaxed response. In contrast, a dog showing a left wag activated by the right hemisphere is feeling a negative or withdrawal response. To the observing dog, this would induce an anxious and targeting response as well as increased cardiac frequency.
Vallortigara doesn't think that the dogs are necessarily intending to communicate those emotions to other dogs. Rather, he says, the bias in tail wagging is likely the automatic byproduct of differential activation of the left versus the right side of the brain. But that's not to say that the bias in wagging and its response might not find practical uses; veterinarians and dog owners might do well to take note.
