A new study led by the University of Oxford has found evidence that kissing evolved in the common ancestor of humans and other large apes around 21 million years ago, and that Neanderthals likely engaged in kissing too. The findings have been published today in Evolution and Human Behavior . This is the first time anyone has taken a broad evolutionary lens to examine kissing. Our findings add to a growing body of work highlighting the remarkable diversity of sexual behaviours exhibited by our