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Happy tail wag, happy dog?
Happy tail wag means a happy dog, right? But is it really that simple or is your dog’s tail wag more complicated than that?
Today we are looking into how dogs communicate with their tails and what underlying emotion a tail wag might display.
As a dog owner you have properly seen your dog using his/her tail in different ways to communicate with you. The happy wag or spin you see when you get home after a long workday to the more insecure frightened tail between the legs telling you that your dog is feeling insecure or frightened about something. The high wag tells you that a dog is confident and happy, while a low wag tells you that a dog is insecure. The lower the tail, the more frightened the dog is (Read more about fear in dogs here).
The science behind the tail wag
Recently scientists have figured out that a tail wag can also display a dog’s most inner feelings. It all comes down to lateralization. A dog’s brain, like a human’s, is divided into a left and a right hemisphere. The left hemisphere of the brain has control of the more positive emotions while the right hemisphere takes charge of the more negative frightening emotions. Just like in humans, the nerves cross on the way from the muscles to the brain, so that the left hemisphere controls the right side of the body and the right hemisphere controls the left side of the body.
Scientist found that the symmetry in which a dog wags his/her tail differs slightly when comparing the right and left side.
This was studied further, and a study have now shown that when dogs greet their owners their tail is more turned to the right, hence the left hemisphere is splurging out happy emotions. This was in contrast to when the dogs were introduced to a stranger, where it was observed that their wag went more towards the left hence an activation of the right hemisphere in control of the more negative emotions (Read more about a dog’s emotions here).
A dog’s wag can change instantly if the situation changes which was seen when the dogs saw their owners from a distance and first wagged a little insecure to the left but once they recognized their owner their wag quickly changed to the right (Read more about the dog-human relation here).
But it is not only for humans that dogs differ their tail wag symmetry. They also use it to communicate with other dogs. This was found in a study where dogs were shown video clips of other dogs wagging either more to the left or more to the right. In the dogs observing, a higher pulse and increased insecure behaviour was seen when they watched dogs wagging more towards the left.
These studies show us the importance of learning to read our dogs body language and how the slightest changes in their body language can tell you how they feel. Furthermore, it also proves that just because a dog wags his/her tail it does not mean that (s)he is happy, it can also be a sign of insecurity and many other meanings science still haven’t figured out. With this knowledge you can help your dog by understanding how (s)he feels in different situations and protect them from uncomfortable scary situations in the future.
Want to know more about dog body language then check out our Dog Body Language Library
Sources:
Quaranta, A. et al. 2007. Asymmetric tail-wagging responses by dogs to different emotive stimuli. Current Biology 17, R199-R201
Siniscali, M. et al. 2013. Seeing left- or right-asymmetric tail wagging produces different emotional responses in dogs. Current Biology 23, 2279-2282
