Scientists have shed more light on how the movements of a dog’s tail are linked to its mood.

Earlier research had revealed that happy dogs wag their tails more to the right (from the dog’s point of view), while nervous dogs have a left-dominated swish.

But now scientists say that fellow canines can spot and respond to these subtle tail differences.

The study is published in the journal Current Biology.

Prof Georgio Vallortigara, a neuroscientist from the University of Trento, said: ‘It is very well known in humans that the left and right side of the brain are differently involved in stimuli that invokes positive or negative emotions.

‘Here we attempted to look at it in other species.’

He added that just as in humans, for dogs the right side of the brain was responsible for left-handed movement and vice versa, and the two hemispheres played different roles in emotions.

Dogs on film

To find out more about how dogs react to the lop-sided tail wags of other dogs, the researchers monitored the animals as they watched films of other dogs.

They measured the pets’ heart rates and analysed their behaviour.

Prof Vallortigara said: ‘We presented dogs with movies of dogs – either a naturalistic version or a silhouette to […]