Eastern Suburbs Dog Training Club

According to a report on the ABC Science website (29/03/2007), dogs wag their tails to the left or right depending on how they’re feeling, Italian researchers say. Tails wag to the right when dogs are happy and see something they want to approach and to the left when they are frightened and confronted with something they want to run away from, say the researchers.

Professor Giorgio Vallortigara of the University of Trieste and team describe these “striking asymmetries in the control of tail movements” as another example of how the right and left halves of the brain control different emotions.

The researchers tested 30 pet dogs, 15 males and 15 females with an age range of one to six years. They placed the dogs in a large rectangular wooden box covered with black plastic to prevent them from seeing out.

Vallortigara and colleagues filmed each dog’s response to four different visual stimuli: the dog’s owner, an unknown person, a dominant, unfamiliar dog and a cat.

“When faced with their owner, dogs exhibited a striking right-sided bias in the amplitudes of tail wagging,” the researchers write. Tails kept wagging to the right when dogs were shown an unfamiliar person and the cat.

The human stranger elicited less wagging than the owner, and the cat the least wagging of all. But when shown a large, unfamiliar and intimidating four-year-old male Belgian shepherd malinois, also kept in a cage, the tails leaned consistently leftwards. Dogs also wagged their tails to the left when they were on their own, suggesting that they like company.

However, it is unlikely that people can benefit from this discovery when approaching a dog. Dogs tend to move about constantly, making the right-left bias often so sub-tle it can only be spotted with video analysis.

Extract from ABC Science website (29/03/2007): abc.net.au/science/articles/2007/03/29/1884414.htm