Murphy is city manager Tony O’Rourke’s dog.  A more relaxed dog you may never see and it is fun to see him lounging around down at city hall.  He is always up to be petted and to wag his approval. But does he wag to the left or to the right?  A recent study reveals that a pup that is wagging his tail on the left side of his body is happier and friendlier than one wagging on the right.

Behavioral researchers from the University of Victoria in Canada, who published their report in the journal Laterality, found that when canines approached a mechanical black Labrador with a moveable tail, they were less wary when that appendage was leaning left. And the results were the same whether the pet's owner was present or not.

"It's ground breaking stuff," says animal psychologist Roger Mugford. "It you're going to present a signal to a dog, it is sensible to put it on your left hand side because that is where dogs tend to look." The researchers also believe that the practice of "docking" cutting the tails of some breeds like Doberman pinchers could disrupt the way the animals communicate with each other. Continues Mugford: "It's another example of the similarity between dogs and humans.

ohn Moore/Getty Images