What are the functions of a dogs tail?

You can tell a lot about what dogs are feeling just by watching their tails. As you may already know dogs use their tails for communicating. They express happiness, aggression, stress and many other emotions just by using their tail. By looking at the position and movement of their tail, you can often tell what dogs are thinking. When a dog wags their tail high and wags it back and forth, they are usually feeling pretty good. When they are interested in something, their tail is usually horizontal to the ground. A tucked tail indicates that the dog is frightened or submissive. When their tail goes from horizontal to upright and becomes rigid, they are feeling threatened or challenged. A tail that is low and wagging indicates that they are worried or insecure.

The tail plays another vital role in communicating. Every time your dog moves their tail, it acts like a fan and spreads their natural scent around their body. One of a dogs most important odours comes from their anal glands, two sacs under the tail that contain a smelly liquid that is as unique among dogs as fingerprints are to us. Every time a dog wags their tail, the muscles around the anus contract and press onto the glands, causing a release of their scent. A dominant dog that carries his tail high will release much more scent than a dog that holds their tail lower. Likewise, a frightened dog will hold their tail between their legs to keep others from sniffing them, and in that way they do not draw to much attention to themselves.

The tail is also important as a means of counterbalance when the dog is carrying out complicated movements such as leaping, walking along narrow structures or climbing. Dogs that run at great speeds tend to have thin tails that are very long in proportion to the rest of their body, and they use their tails as a counterbalance when making tight turns. Their tails may increase their agility and ability to turn quickly, so that they can keep up with their prey. Tail muscles are also important in stabilizing the vertebral column and supporting the action of the extensor muscles of their back, as well as those of the croup and buttocks.

Some dogs also use their tails as rudders when swimming. Dogs bred for swimming frequently have tails that are thick, strong and very flexible, which helps them to move easily through the water and make quick turns.

Some dogs also use their tails for insulation. Nordic and Arctic breeds  like Huskies have bushy or plumed tails with long dense fur. When lying down they may place their tail over their face to keep out the cold.