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why do dogs wag their tails


Why do dogs wag their tails?

The reasons behind the wiggles

Dogs’ wagging tails are synonymous with happiness and excitement, but the behavior can also represent a range of emotions like worry and aggression. Veterinarian and pet health advocate Dr. Aliya McCullough explains all the ways dogs communicate with their tails.

Why do dogs wag their tails when they’re happy?

It’s not fully understood why dogs wag their tail, but it’s believed the body language evolved from balance and swimming. Now, a wagging tail is a clear indicator of a dog’s mood and intention. 

Do dogs wag their tail on purpose?

01: Happiness 

The speed of a tail wag can be very telling. Often, the faster the wag, the more excited the dog. A relaxed, fluid wag is commonly a sign of a happy pup. If their tail is held high as it wiggles, that’s most likely a welcoming, happy sign. 

Dogs whose entire bodies wag with their tail are often overjoyed to see you. These pups show their excitement in one big booty shake. When you spot this body language bounding towards you, we encourage you to take part in the dancing. 

02: Worry

A low wag can signal nervousness or concern — for example, a slow and low tail wagging is often seen when a dog meets a person or animal for the first time. If only the tip of the tail is raised or wagging, be more cautious. This type of tail wag means the pup may want to interact but on more controlled terms. It’s a stiff, rigid tail that often communicates worry or hostility.

Most importantly, there’s no set tail-wagging speed that determines if a dog is happy or angry — you need to use other non-verbal cues to interpret mood correctly.

03: Aggression

A tucked tail between a dog’s legs can reveal fear, apprehension or even aggression in certain situations. Stop interacting with a dog and slowly move away if you spot this type of behavior. 

Why do dogs wag their tail in their sleep?

Tail wagging can happen when your dog isn’t fully aware of it, like when they’re sleeping. Dogs usually wag their tails while sleeping because they are in a state of deep relaxation. 

Do dogs wag their tail alone?

Dogs wag their tail even if their favorite people aren’t around. If anything excites, aggravates or scares them (including sounds of other animals or people), there’s a strong chance their tail is wagging. 

Can dogs be happy without wagging their tails?

If a dog suddenly stops wagging their tail, it could be a sign that they’re feeling threatened. It’s important to respond to this behavior cautiously. 

We hope your pup never worries or feels aggressive, but if they experience those moods through tail wags, you’ll know exactly how to respond. And, when they do a full-body wiggle around you, you can feel good knowing they’re excited. 

The Dig, Fetch Pet Insurance's expert-backed editorial, answers all of the questions you forget to ask your vet or are too embarrassed to ask at the dog park. We help make sure you and your best friend have more good days, but we’re there on bad days, too.

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