"I never smile if I can help it. Showing one's teeth is a submission signal in primates. When someone smiles at me, all I see is a chimpanzee begging for its life."
"[I]n countries like Germany, Switzerland, China, and Malaysia, smiling faces were rated as significantly more intelligent than non-smiling people.""But in Japan, India, Iran, South Korea, and... Russia, the smiling faces were considered significantly less intelligent.... In countries such as India, Argentina, and the Maldives, meanwhile, smiling was associated with dishonesty...."
At the link — to "Why Some Cultures Frown on Smiling/Finally, an explanation for Bitchy Resting Face Nation" in The Atlantic — there are some charts arraying the countries from one extreme to the other....