Kissing is older than humanity itself, according to Oxford researchers who traced the behavior back to a common ancestor of today's large apes that lived roughly 17 to 21.5 million years ago. Their analysis also concluded that Neanderthals likely kissed, and that they may have locked lips with early modern humans.
The team won the 2026 Ig Nobel Prize in biomechanics on Sept. 3 in Zurich, at the first Ig Nobel ceremony held outside the United States, for devising a precise definition of kissing that works across ants, birds, polar bears and humans, according to the Ig Nobel organizers. The work also bears on a less romantic question: kissing is one of the oldest ways humans share germs.
