Yawning has perplexed scientists and researchers for decades. But humans aren’t the only species subject to yawning. Dogs (and rats and parakeets) have also been known to unwillingly open their mouths, inhaling in a gesture of exhaustion. But why do dogs yawn and what does yawning really mean in dogs? Is it truly about tiredness, sending oxygen to the brain … or is it something more complex?

“Dogs, just like people, will yawn when they are tired,” explains Sara Ochoa, DVM, of DogLab. But is that really all there is to the phenomenon of dog yawning?

Why do dogs yawn when they’re tired?

Why do dogs yawn when they’re tired? As Dr. Ochoa explains, dogs yawn when they are tired the same way that humans do. According to WebMD, yawning stretches the jaw, therefore increasing blood flow in the neck, face and head. The intake of breath is deeper than “normal” breathing, which causes a downward flow of the spinal fluid and blood from the brain. The cooler air that is inhaled during yawning enters the mouth, cooling the spinal fluid and blood.

Scientists speculate that the reasoning for this seemingly involuntary intake of cool air might be to cool down blood in the brain that’s too hot. Those fluids trickle down, bringing cooler blood from the lungs to the extremities. So, more than yawning being about exhaustion, it might very well may be about body temperature. Of course, yawning is also a part of fatigue.

“[In dogs], this is them stretching their facial muscles and trying to keep themselves awake,” Dr. Ochoa says.

Why do dogs yawn when they don’t like something?

It’s a less common question … but why do dogs yawn when they’re not pleased? Dog yawning happens often during training or traveling or sometimes even on a walk.

According to Dr. Ochoa, it’s no coincidence. Dogs tend to yawn when they’re less-than-thrilled about what you’re asking of them.

“This is them showing that they do not like something. They may be more stressed [in a particular situation],” Dr. Ochoa adds.

As you can imagine, that often makes for a lot of yawning during training class.

“If a dog is yawning in training class, he is either tired or bored,” Dr. Ochoa says. “It can be a good sign or a bad sign.”

Why else do dogs yawn?

Other reasons dogs can yawn might be stress or anxiety. In situations like traveling or even in obedience class, dogs might experience levels of stress or anxiousness. Another situation in which dogs commonly yawn? At the vet.

“Your dog may be stressed or nervous. We will see dogs who come into the veterinary office for exams that will yawn,” Dr. Ochoa explains.

How do you figure out the answer to, “Why do dogs yawn?”

Of course, differentiating which yawn is which is the hard part.

“If your dog is tired, that is the goal of the training class,” Dr. Ochoa says. “You know that your dog may not want to do any more training. If your dog is bored at training, you may need to change your training to something more difficult.”

Alternatively, a tired dog might indicate a dog that listens more readily than a highly-energized one. (They say to bring your pup to the dog park before training class for a reason, right?!)

How can pet parents stop dog yawning?

Yawning in dogs is as much an enigma as it is in humans. While yawning is common in most vertebraed species, we can’t be entirely sure of why either we or animals yawn. There are indications, of course — exhaustion, a need for cooler blood and fluid in the brain, not liking something or boredom — but until more is known about yawning in all species, we pretty much have to take it as it comes.

For both humans and dogs, that means an inability to stop yawns.

“Yawning cannot be stopped or prevented just like in people,” Dr. Ochoa concludes. “If you are tired, you cannot help but yawn.”

Same goes for Fido!

Thumbnail: Photography © Przemysław Iciak | iStock / Getty Images Plus.

About the author

Stephanie Osmanski is a freelance writer and social media consultant who specializes in health and wellness content. Her words have appeared in Seventeen, Whole Dog Journal, Parents Magazine and more. She is currently pursuing an MFA in Creative Writing at Stony Brook Southampton and writing a memoir. She lives in New York with her Pomsky, Koda, who is an emotional support animal training to be a certified therapy dog.

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