In the Western world, Valentine’s Day expressions of affection are closely linked to mouth-to-mouth kisses. I remember feeling envious years ago when a colleague found a card in his pigeon-hole ...

Breakthroughs, discoveries, and DIY tips sent six days a week. Terms of Service and Privacy Policy. Humans are born with instincts for crying and smiling, but not for ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. “The meeting of ...

Humans have been kissing for a long time, according to an article published in the journal Science on Thursday. Researchers studied cuneiform texts from ancient Mesopotamia in an effort to unlock the ...