Ask Dr. Universe: Dogs use their tails for balance, communication and more

Washington State University

Dr. Universe: Why do dogs have tails? – Bailey, 7, Ohio

Dear Bailey,

My best friend is a golden retriever. When I get home, she greets me with a goofy smile and a big wag of her fluffy tail.

I talked about why she has a tail with my friend Jillian Haines. She’s a veterinarian at Washington State University.

She told me dogs use their tails for lots of things. Tails help dogs balance while running, jumping or swimming. Tails help dogs communicate with each other and other animals. Some dogs in the Arctic–like sled dogs–use their tails to stay warm. They curl up and cover their noses with their fluffy tails.

When a dog is moving, its tail acts as a counterbalance. When you need to balance yourself, you probably stick out your arms. That’s what a dog’s tail does, too. If the dog starts tipping one way, it can stick its tail the other way to stay balanced.

“It is also used for making sharp turns,” Haines said. “Breeds like greyhounds that are fast runners, have a whip-shaped tail. They can use it to make a quick turn. It also balances them when they’re jumping.”

Some dogs are good swimmers. They use their tails for balance and steering in the water. It works like a boat’s rudder.

Tails are also important for communication.

“It’s how dogs talk to each other–and it’s part of how they talk to us,” Haines said. “Depending on how that tail is held, it can tell us the dog is feeling happy or excited. It can tell us the dog is scared. It can say they’re ready to play. Or it can say to stay away.”

Not all tail wags are the same. A happy dog usually holds its tail softly and wags it in a chill way. An angry dog might wag its tail, too. That dog might hold its tail high and stiff. It may wag its tail very fast.

The direction of the tail wag sends a message, too. Dogs usually wag their tails to the right when they see something they like–such as their human. They usually wag their tails to the left when they want to stay away from something–like another aggressive dog.

But some dogs are born without long tails. These include corgis, Boston terriers, bulldogs, and some Australian shepherds and spaniels.

“For those dogs, having a tail can make it harder for them to do their jobs or can be a source of injury,” Haines said. “A low-to-the-ground herding dog could get their tail stepped on by a cow. A tail can get stuck when squeezing through obstacles or tight areas.”

So, humans have bred some dogs to have a bobtail instead of a long tail. These dogs can still wag.

“That little wagging nubbin is just as cute and rewarding to see as a big fluffy tail,” Haines said.

Just don’t tell that to my bestie.

Sincerely,

Dr. Universe

Adults can help kids submit a question at askdruniverse.wsu.edu/ask.