BY: MARIYA GUZOVA

If you’ve ever thought about it for longer than a second, then you’ll probably agree that kissing is pretty weird, perhaps even gross. Pressing your open mouth into another person’s open mouth and exchanging saliva and germs seem like a pretty odd way to express affection or sexual attraction. And yet here we are.

In the attempt to redeem ourselves after making out with scores of questionable strangers at hazy parties, we may want to explore the scientific reasoning behind kissing.

Research published in the American Anthropologist rejects the claim that kissing is a universal human behaviour. Out of the 168 cultures studied, only 46 percent practice romantic-sexual kissing. While this is somewhat misleading in that 46 percent of cultures still make up 90 percent of the world’s population, it does suggest that kissing is not an animal, instinctual behavior but rather a learned, social one.

The research also found that the frequency of kisses correlated with the level of complexity within a society. In other words, the more socially complex a culture, the more smooches.

There is evidence to suggest, however, that kissing is, in fact, an instinctual response, much like other forms of affection such as hugging, which has been scientifically proven to release trust hormones like oxytocin between humans who aren’t blood related.

The origin of kissing is linked to physical intimacy demonstrated by animals like chimps and bonobos. Most chimp kisses happen between males as a form of reconciliation. Bonobos even practice French kissing, although they are also known to have huge orgies and have sex every time they meet a new bonobo. Another possible origin comes in the form of a mother passing chewed food from her mouth to her baby’s mouth. While these origins aren’t exactly Nicholas Sparks novels, they do provide an explanation for how humans started kissing.

The most accepted theory for kissing, however, has to do with humans’ terrible sense of smell. Animals, including humans, release chemicals called pheromones, which transmit information about a person’s biological makeup. Most animals can detect these pheromones without being tongue deep in each other, but no such luck for us humans and our lousy noses.

The origin of kissing is linked to physical intimacy demonstrated by animals like chimps and bonobos. Most chimp kisses happen between males as a form of reconciliation.

Kissing allows humans to get close enough to smell each other’s pheromones, which are found in high concentrations in the sebum around the nose and mouth. Sebum is the science-y name for oily skin. People tend to prefer the pheromones of people whose immune systems differ from their own. This is because the genetic combination of these immune systems would be beneficial for their potential offspring.

Additionally, research suggests that people’s breath and saliva carry information about a person’s general health, and for females, whether or not they are ovulating. Kissing also induces the same hormonal response in the brain as hugging, promoting trust and emotional connectivity. In fact, studies have found that many sex workers refuse to kiss their clients as a technique for establishing emotional distance, demonstrating the intrinsic connection kissing has to romance and partnership.

Essentially, kissing acts as an evolutionary screening tool for finding your optimal baby daddy/mama.

So next time you find yourself regretfully reminiscing on last night’s adventures, remember that you were only performing your evolutionary duty for the greater well-being of the human species.

Image sourcing: istock.com,  Life Daily,  Baklol