Author Vallortigara and his team have done serious research on this subject, selecting many dog types, mixed and pure breeds. See the study and results below:
For the most recent study, Vallortigara and his team used videos of a dog or dog silhouette wagging its tail mostly to one side or the other, or not wagging at all. The only thing moving in the wagging videos was the tail.
The video was shown to 43 dogs, including mixed breeds, Rottweilers, Beagles, Boxers, Border Collies, and German Shepherds, who were equipped with heart rate monitors. When the video dog wagged primarily to its left, indicating a negative response, the dogs in the study tended to have faster heartbeats than when the video dog wagged to the right or not at all. The dogs’ response also suggested a higher degree of stress.
Left-brain activity in dogs resulting in tail wagging to the right means they are having a positive response that invites another dog to approach. Right-brain activation suggests a negative withdrawal response.
The conclusion of the study is that dogs who see another canine wagging his tail to the left feel anxiety and have a raised heart rate. At the opposite, if they see another dog wag to the right they are far more relaxed and happy.
For more information on this interesting study go to Healthy Pets. Next time you are out and about with Rover or Spot check out how he reacts when seeing another dog approach. His tail may tell you if there is anything to fear!
