On the Trobriand Islands, off the east coast of Papua New Guinea, lovers kiss by sitting face to face and nibbling at each other's eyelashes, 'which I think to many of us today doesn't sound like the height of romance but for them that did the trick', says Kirshenbaum. 'There's the Malay kiss that Darwin described, where women would squat down on the ground and men would kind of hang over them and take a quick sniff of each other вЂ“ take a sample of their partnerвЂ™s scent.' Those cultures that do not kiss lip on lip find other ways to be intimate, says author Sheril Kirshenbaum. 'But I think the key to the human universal of kissing, or the absence of it, is that people's sensuality can be met in many ways other than just kissing,' says Jankowiak. In the video below BBC Reel explores some of the other theories for the origins of kissing, which include one suggestion that clothes might have been an important driving factor. This is something that is seen in our closest ancestors вЂ“ chimpanzees вЂ“ as well as other great apes. The mothers of our ancient ancestors might have pre-chewed our food for us in our early years, and transferred it directly into our mouths. There is also a suggestion that mothers and their children bond over lip-on-lip kissing because of something called ' premastication food transfer'. In one case, it might be that we associate lip touching with breastfeeding, and that reflex is innate in everyone. Two theories for why humans have a need to kiss stem from the idea that as babies we have an innate liking for lip touching.

William Jankowiak, a professor of anthropology at the University of Nevada Las Vegas, found that only 46% use lip-to-lip kissing in a romantic sense, excluding things like parent-child kissing or greetings. Less than half of all societies kiss with their lips, according to a study of 168 cultures from around the world.

A kissing face for facebook