Most of us have seen this happen and yet we do not understand why it happens.
Some people think its submissive behavior. Others think they have mimicked human bahavior.
I remember the first dog I ever saw that did it, and her name was Zelda! She was a mutt of total unknown parentage. We found her in the parking lot behind the grooming shop one morning when we came in. She might have been 8 weeks old and she already SMILED! We had no luck at all in placing her because of her smiling. People thought she was being mean. We had her for 8 years and she smiled until the day she died.
My next smiler was an Austrailian Shepard name Lacey. She smiled all the time. In fact, she smiled so much that the scottie she lived with learned how to smile as well.
Truth be told I have NO Idea why they do it. I just think its precious!
In many cases, like Princess, the yorkie in the picture above, they will do it on command. Whenever you say her name, she smiles. If you say SMILE, she smiles. If someone new comes in the shop and speaks to her she smiles. Her dads say she smiles for several minutes every day when they come home from work.
Most dogs that smile do it when they are happy. My dog Scrappy, whom I have yet to catch doing it on camera, will even do it at bedtime, as if he is saying PLEASE MOM don't make me go up!
Scrappy, his brother Alley Oop and their mom Maxie all smile!
I have also seen dogs in the same household as a smiler learn to smile.
SO, while some people think that dogs can't smile for real and if they do there is something lurking behind it, I don't think so.
I think they can. I think it's cute, learned behavior that because the dog gets positive attention from doing it, they continue doing it.
So don't be afraid when dogs smile. Smile back! Bet they think you are being goofy as well when you do!