Wagging Tails are a form of Communication for Dogs
For decades, the saying that a dog is a man's best friend has thrived. Dog owners love and care for their four-legged animals as if they were their own child. Since dogs are extremely important in people's lives, several researchers have set out to study this animal. In a new study, Italian researchers observed dog behavior through the tail. They reported that the direction of a wagging tail is a form of communication.
"The direction of tail wagging does in fact matter," Giorgio Vallortigara, a professor of neuroscience at the University of Trento, and director of the university's Center for Mind/Brain Sciences, wrote. "That is amazing, I think."
For this study, Vallortigara and colleagues Marcello Siniscalchi, Rita Lusito and Angelo Quaranta, who are all from the University of Bari Aldo Moro's Department of Veterinary Medicine, analyzed the behavior of 43 dogs from varying breeds. The dogs were presented with projected images of a dog with a wagging tail. The researchers noted three trends. First, when the dog's tail wagged to the right, the majority of the dogs watching appeared to be relaxed. Second, when the dog's tail wagged to the left, however, the dogs became more anxious, which was measured via heart rate. Lastly, when the tail was not wagging, the dogs were just slightly less relaxed than the very first situation.
The researchers believe that the dogs' reactions to the direction and movement of another dog's tail indicate brain hemispheres that are very similar to humans. The team explained that when the tail wagged to the right, the dogs' left hemisphere was activated. This hemisphere has been tied to positive responses and social approachability. When the tail went to the left, the right hemisphere was activated and this section of the brain has been tied to negative responses, anxiety and flight from danger.
This is not the first study to look into the significance of a dog's wagging tail that the research team has done. In 2011, the team had published a paper stating that when dogs greeted familiar humans, they tended to wag their tails vigorously to the right. When the dogs greeted dominant dogs that were unfamiliar, their tails tended to wag to the left.
"It seems that one interpretation of these findings is that dogs might use tail-wagging direction as an indicator of the state of the other animal ... and somehow match that state [emotional transfer] or use it as a signal of impending danger in the environment," the authors wrote.
The study was published in Current Biology.