Why do we make out?

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The kiss has been etched into our culture through movies and media as one of the ultimate romantic gestures. So, for many of us, it’s thought as something universally human. However, researchers from the Kinsey Institute at Indiana University say they have evidence showing the contrary — not everyone does it, and for good reasons.

The paper, published in the journal American Anthropologist, asks a simple question: “Is the Romantic-Sexual Kiss a Near Human Universal?” The group looked at 168 different cultures to understand where kissing occurs, and where it does not.

They were surprised to find that only 46 percent of cultures engage in romantic kissing. Not only did a majority not engage in the act, but also some even found it uncomfortable or disgusting.

Justin Garcia, an assistant professor of gender studies, conveyed his surprise at the results in a press release:

“We hypothesized that some cultures would either not engage in romantic/sexual kissing, or find it to be a strange display of intimacy, but we were surprised to find that it was a majority of cultures that fell into this category. This is a real reminder of how Western ethnocentrism can bias the way we think about human behavior.”

So, where didn’t people tend to lock-lips? The researchers found no evidence of “kissing cultures” in Central America, Sub-Saharan African, New Guinean, or Amazonian foragers or horticulturalists.

However, human kissing seems to be a way to assess the “chemistry” between two people, he said, or may even offer an opportunity to examine a potential partner’s “health via taste and smell, and in some ways to assess compatibility with each other.”

Garcia said:

“There is likely a biological underpinning to kissing, as it can often involve exchange of pheromones and saliva, and also pathogens , which might be particularly dangerous in societies without oral hygiene, where kissing may lead to spread of respiratory or other illness. But this is only in societies that have come to see the erotic kiss as part of their larger romantic and sexual repertoires.”

The researchers did note a link to how the social complexity of a culture related to where kissing was present, but as to how a culture makes the shift to the kiss remains uncertain.