While two strangers might serendipitously find themselves chemically compatible, more often the best kisses grow out of an emotional connection and ambience, Kirshenbaum says. “So much of a great kiss ...

Kissing is so common many of us don’t think there’s more to it than meets the lips. Kissing is a universal language — a cross-cultural phenomenon, a sign of love, affection and kindness. But it could ...

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