When did kissing romantically evolve? We asked the public to see what they think.
There is wide debate over when humans began kissing romantically. Ancient texts hint that sexual kissing was practised in ancient Mesopotamia and Egypt at least 4500 years ago, but because such kissing has been documented in only about 46 per cent of human cultures, some argue it is a cultural phenomenon that emerged relatively recently in human history.
However, there are hints that Neanderthals exchanged oral bacteria with Homo sapiens, and chimpanzees, bonobos and orangutans have all been observed kissing. So it is possible that the behaviour goes back far further than historical texts reveal.
