The Science -and Silliness - of Kissing

A kiss is a lovely trick designed by nature to stop speech when words become superfluous. - Ingrid Bergman

Think about it. If a spaceship full of aliens landed on earth to observe human behavior, how on earth would we explain the act of kissing?  One person touches another person with their lips.  Not, of course, lips to lips alone.  Lips to cheek, lips to neck, lips to – well, just about any other body part can be considered.  Imagine the polite but nevertheless obvious squirming with embarrassment that could be involved on either or both sides of the species divide: especially if they landed on Valentine's Day.

Kissing is a means of getting two people so close together that they can't see anything wrong with each other. – Rene Yasenek
An immediate question might be what is the act for?  The reply could constitute the making of a list that even the most list-seeking list seeker on the internet might find overlong.  Tongue nevertheless in cheek, most people would associate kissing with love and sexual desire and the aliens would probably accept this as part of our self-evidently bizarre mating habits.  When this basic question is elaborated upon, however, to include greeting, respect, sympathy, luck giving, affection and, most puzzlingly, false empathy then who would blame our visitors from outer space from turning tail and leaving this planet in a huff?

I am in favor of preserving the French habit of kissing ladies' hands - after all, one must start somewhere. - Sacha Guitry
The origins of the word are old enough – the Old English language gifted the world the word kiss from their own – ‘cyssan’.  Origins of the word aside, the reason for this most simple yet complex act to exist is still perplexing philematologists (those who study kissing).  They cannot decide whether or not kissing is a learned behavior or if it is instinctive. 

A kiss is something you cannot give without taking and cannot take without giving - Author Unknown
Many believe that it is related to grooming and this can be seen between different species on the planet.  Due to the willingness of people to anthropomorphize animals and gleefully spread photos of these occurrences on the internet (guilty as charged) then it is easy to fall in to this potential trap.  It is just as likely that kissing evolved from mothers chewing food for their infants and then passing it from mouth to mouth. So, perhaps the act of kissing does not have a sexual origin at all.

I wasn't kissing her, I was whispering in her mouth. – Chico Marx
Kissing proper involves the body doing quite a lot of work.  Thirty four of the face’s muscles are used in the act as well as a whole host of the body’s postural muscles.  The most important of these is your sphincter muscle - we kid you not.  Your posture may have just changed when you read the last sentence but allow yourself a second or two to relax your sphincter a little.  The body has over forty sphincter muscles and the orbicularis oris muscle (known to friends as the kissing muscle), consists of lots of fibers around the hole that is your mouth all of which have varying directions.  If you play a brass instrument you orbicularis oris will be particularly well developed.

Kiss me and you will see how important I am. – Sylvia Plath
Let’s add, for good measure, the tongue.  When used in the act, kissing becomes French Kissing, or to use the more basic UK slang available to us, it becomes a damn good snog.  This is where the tongue of one or both participants enters the mouth of the other.  (The aliens are now, of course, way past Jupiter, leaving us to ramble on our own).  While we might not like to be seen to encourage teenagers in this act, many evolutionary biologists believe that there is a real function here. 

The first kiss I had was the most disgusting thing in my life. The girl injected about a pound of saliva, into my mouth, and when I walked away I had to spit it all out. – Leonardo DiCaprio
The object of the exercise – as much as prolonged and intense sucking face needs an excuse other than the obvious – is to check out the potential partner’s immune system through the saliva.  It could also be used to avoid breeding with a relative.  Quite how this is done by the body on an instinctive level remains a mystery but many people have been put off further bodily exploration and penetration by a French kiss with another for reasons upon which they cannot quite put their finger.  No need, it seems when the tongue has done it for you.

Kiss and make up - but too much makeup has ruined many a kiss. - Mae West
Of course the kiss is not always a prelude to getting ‘down on it’.  Kisses are mostly used to express affection between people - quite often to say hello or goodbye.  More often than not the lips will just about touch the cheek of the recipient and sometimes no contact at all will be made.  The emergence of the air kiss, a pretense of the act, accompanied by ‘mwah’ as an exhortation (with or without exclamation marks depending on the relationship) could perhaps be an evolution of the act.  Or, it could simply be an expression of desire – the desire to keep one’s (overdone) makeup intact.

People who throw kisses are hopelessly lazy. – Bob Hope
The most likely root of the air kiss is the blown or thrown kiss, which is often done to audiences but can be done between just two people where the physical distance between the two prohibits the act itself.  Sexuality can be removed from the act altogether when the act of kissing is used to display sympathy or reconciliation with others.  It can also be used to offer luck or to celebrate success without any sexual intent whatsoever.  Same sex kissing between men who are heterosexual is quite common in many countries. 

I married the first man I ever kissed.  When I tell this to my children they just about throw up. - Barbara Bush
The kiss is like an iceberg.  This article could be seen as the top ten percent peeking above the water.  With so much more left to say – and with the aliens just having pushed the warp drive button as they pass by Pluto (saddest of ex-planets) – perhaps you might feel the urge to go and do some practical research. Happy kissing!

Kuriositas would like to thank Juan Felipe Rubio (Flickr User Sicoactiva) for making the wonderful photo collages available under Creative Commons.