When did kissing originate? Scholars make educated guess

(NewsNation) — Researchers have made an educated guess about when kissing began, dating the practice at somewhere between 17 million and 21.5 million years ago.
But by kissing, scientists don’t mean the type of lip-locking that humans engage in, often to show affection. Rather, they zeroed in on “non-agonistic interaction involving directed, intraspecific, oral-oral contact with some movement of the lips/mouthparts and no food transfer.”
Researchers studied data about modern primates that are known to kiss, including chimpanzees and