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 ...
Kissing feels instinctive and intimate, yet scientists now argue it is a surprisingly recent and uneven addition to human behavior. Instead of a single romantic origin story, the evidence points to a ...
Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. “The meeting of ...