Maybe, but maybe not!
We humans tend to get warm and fuzzy feelings when we see dogs “smile.”
It’s true that some dogs’ mouths open in a cute smile when they are relaxed and happy. But a dog with his mouth open could alternatively be panting from pain, stress, or fear.
Can we tell the difference?
The following pairs of photos show my dogs stressed (left column) and relaxed (right column). The dogs have their mouths open in all the photos.
The usual disclaimers apply. When you run across someone’s still photo with no context, you can’t fairly make assumptions. It might have been taken during the millisecond in which a dog changed his expression. It could be misleading for a dozen other reasons. Videos are better, but we still miss context and may lack knowledge about the particular dog. But in this case I can vouch for the emotional states of my dogs, and I believe they are accurately represented by the photos with recognizable indicators.
Mind the Mouth
What all these photos have in common is a common “tell” regarding the dog’s emotional state. Look at the corners of the dogs’ mouths, also known as the commissures. In all cases, they are drawn back and stretched tight in the “stress” photos. In most of those photos you can also see the muscles bunched up in that area.
The photos have other indicators of the dogs’ emotional states as well. For instance, three of the stress photos have what is called a “spatulate” tongue, also usually connected with stress. The dogs’ eyes are markedly different between the stressed and relaxed photos as well.
I hope these comparison photos can help some folks figure out their own dogs’ facial expressions, and maybe overcome our wiring–which is very difficult–to assume that an open mouth means a happy dog. Please share this blog post wherever it might be useful. The photos may also be used for educational purposes if credit is given. I’d appreciate it if you would drop me a line through the sidebar contact telling me about the use.
You can see labeled versions of the “Clara stressed” photos (and many more) in my post Dog Facial Expressions: Stress. You also might be interested in my Dog Body Language Posts and Videos page.
Many thanks to Julie Hecht at Dog Spies for giving me the idea for this post.
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I love following your blog! This post was particularly wonderful, great to have the side-by-side comparison. Really helps to see the difference.
Thank you very much, Robyn!
Being a Texan and all, I wonder how heat stress affects this kind of body language? For example, when my dogs are panting heavily from the heat, it seems to produce the kind of facial tension and commissure retraction usually associated with stress. Is that just physiological or is the dog psychologically stressed due to the uncomfortable heat? I also tend to see facial tension and spatulate tongue in situations where I would characterize my dogs more as aroused than stressed, such as when entering a new place or after running hard. But maybe I’m muddling those terms? Would one expect to see a few but not many stress signals in a demanding situation such as in a crowded public place and conclude that the dog is somewhat stressed, but not distressed? I’m confused as to where to draw some of these lines. I try be a good steward of my dogs’ behavior and remove them from situations in which they are uncomfortable, but especially with my nervous dog I see more subtle signs like this in just about every environment, which is discouraging. Hope that makes sense, sorry to ramble, and love the blog!
Amelia, these are all great questions. And the answers are, I don’t know, I don’t know…. You make great points, though. I think there is a ton of nuance in all this. I felt confident in posting these photos because I knew the situations and also, there were many other signs besides the commissures in each photo.
But I know also that I have seen my dogs with their commissures pulled pretty far back when they were very hot. I don’t think I’ve seen spatulate tongue in any situation except stress though. (But see below.) Hope some others chime in.
I have a picture that illustrates exactly what you are talking about with a combination of heat and arousal, and perhaps stress from the heat. This is Summer after having run around after an animal in the back yard in the heat. She is very predatory and she was very aroused. But it’s over, and she’s panting. She may just be so hot that her mouth is open that far. But I imagine those arousal hormones are still washing all around. She looks kind of wild eyed, too.
I don’t always know where to draw the lines, but I agree that not all stress is bad or to be completely avoided. There’s also the distinction between distress and eustress, but even those terms I haven’t seen consistently defined.
I’m glad you enjoyed the blog. This is the kind of thing that can prompt more questions than it answers, can’t it?
Hi Eileen –
Excellent topic! I appreciate any encouragement to look at our dogs and understand what they are telling us through their facial expressions and body language.
Strangely, the first thing I noticed in the pictures you provided were not the subtle differences in the mouth that you pointed out but the set of the ears and eyes in the comparison. In the case of the “stressed” dogs, ears were set back in what I call an “apprehensive” posture. The eyes have a similar “apprehensive” look as they seem to me to be slightly wider open and ready to scan for any possible problem.
I also appreciate your caveat about analysing photos. You can accurately point out what is happening in these photos because they are your dogs and you knew the circumstances in which they were taken. Like you, I am very reluctant to try to assess a dog from a single still photo without any additional context.
Valuable blog. Thanks for posting!
Thanks, Eric. You are right on about the ears and eyes. Actually my favorite comparison in all those photos is Summer’s eyes. As you noted as a general observation, hers are wider open in the “stress” photo, so much so that their shape is different. Round vs more oval. Her other photo has to me that hard-to-describe quality of “soft” eyes.
Thanks for the comment!
Reblogged this on and commented:
A topic on our minds, we recently came upon this Great article about signs of stress in your dog. It’s true, some dog’s are not “smiling” or “happy” when their owners post photos of them with tongues out, teeth bare (etc.) If anything, your dog is probably wondering what in the heck are you doing?! Like some humans, not all dogs are…photogenic. I know I am not, whenever someone pulls out a camera, I personally…RUN.
Don’t forget to check out – Dog Facial Expressions: Stress – posted by the same author. This Article will also give you some good pointers for signs of stress in your dog, like whale eyes or panting.
Open mouth does not mean happy or safe.
Needs to be said over and over. Not sure where that myth came from, but hearing too many people repeating it.
Great post, and one that tugs at my heart quite a bit. We actually nicknamed our first dog Isis “Smiley Bird” because she had such a great smile. She’s my avatar, actually. Looking back, I realize that some of those smiles may have been stress. Like when I dressed her up in a Snow White costume, and thought she looked so happy, for example…
Awww, she’s cute. I hope you don’t feel too badly. It’s a rare person who hasn’t made this mistake. I’m sure I still make it at times. Thanks for posting, and telling about Isis.