Why do dogs wag their tails? © Getty Images

Why do dogs wag their tails?

This iconic canine behaviour allow dogs to express their mood.

Asked by: Joe Goodman, via email


Dogs ‘talk’ with their tails. The position of the tail can tell us a lot about how a dog is feeling; hung low suggests fear and submission, whereas held high is a sign of dominance and arousal.

A wagging tail often conveys happiness and excitement but neuroscientists at the University of Trento in Italy have found that the speed and direction of wag is important in ascertaining if the dog is either negatively (slow and to the left) or positively (fast and to the right) stimulated.


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