Can dogs tell when you're smiling?

Related questions

1. Can smiling make you feel happier?
2. When did Harvey Ball create the smiley face?
3. What is a real smile called?
4. Does smiling mean your happy?
5. Can you fake a genuine smile?
6. Are smiles contagious?
7. Does smiling give you wrinkles?
8. Why your smile is beautiful?
9. What it means to smile?
10. Is it bad to smile too much?

Tags

1. #knows
2. #elsewhere
3. #happy
4. #probably
5. #humans
6. #friendly
7. #faces
8. #friends
9. #indicates
10. #study
11. #smile
12. #signs
13. #smiles
14. #recognize
15. #distinguish
16. #tails
17. #strangers
18. #since
19. #smiling
20. #learn