Why Do We Kiss? The Surprising Science Behind Making Out

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Why do people kiss? Science has a few theories as to why we lock lips.

Why Do We Kiss?

Why do we kiss? Picture it. You've finally landed a date with a person you've had a crush on for forever. It went great, you both enjoyed dinner and witty banter flowed easily.

You were a delight. Congratulations!

But now it's the end of the night, and they're dropping you off home. It's the perfect moment...

You proceed to lean forward, your eyes close, your breath hitches, your heart is pounding.

Finally, you put your mouth hole on their mouth hole -- where you stuff food on where they stuff food -- orifices cramming up against each other.

For some reason, it's incredibly romantic. So, why do we do it? Why do we kiss?


You are probably too caught up in the moment when it's happening, but have you ever thought about how weird kissing actually is?

Why, as humans, do we find putting our lips and tongues on another person's is romantic, and erotic?

Do Other Animals Kiss?

Where does this behavior come from? Do other animals kiss?

The simplest answer to "Why do we kiss" is that it feels good -- lips are packed with sensitive nerve endings.

But some scientists believe that there is more behind kissing, especially why we do it in the first place.


How Did Humans Learn To Kiss?

Experts suggest that kissing is a learned behavior, which may date back to when our ancestors mouth-fed their toothless infants.

I know, it's hard to believe that the one thing you wanted so desperately to do in the basement of your high school boyfriend's house all originated because some moms were baby-birding their spawn. It really takes the romance out of things.

Evidence that supports the learned behavior theory is that a number of cultures do not kiss romantically. In fact, less than half of the cultures kiss romantically.

Meanwhile, it is such a norm in our society that all of our movies end with the big smooch.

20th Century Fox

Kissing Is Instinctive Behavior.

While it is not common, other animals do kiss. Most notably, our animal relative the bonobo is a serious make out fiend. To put it into perspective, if these monkeys knew how to play spin the bottle they would do little else.

Bonobos are known to slip each other a little tongue to make up after a fight, to comfort each other, and, truly just like humans themselves, for no reason at all.


A Theory On Why We Kiss

The most widely accepted theory of kissing is that humans, especially women, are literally trying to "sniff" out a perfect mate.

When we get close enough to another person to lay some lovin' on 'em, we are able to instinctually smell their pheromones. For women, this is important.

Women are smelling if their chosen mate has different immune system proteins from her own, which will eventually make stronger, healthier children.

In fact, scientists may argue that someone a woman may consider a "bad kisser" simply just doesn't have the right smell. (Which is also what I tell myself whenever someone suggests I am a bad kisser. Not that this happens often. I swear.)

Women are also less likely than men to continue a relationship with a "bad kisser." This may be because, somewhere in our reptilian brains, we believe that mating with the wrong person will result in nine wasted months and a baby with a lower chance of survival.

There's still a lot to study in regards to homosexual kissing -- but heterosexuals, next time you find yourself in the throes of passion, try not to think: "Am I sticking my tongue inside this person's mouth because it feels good or am I just trying to feed them like a toothless infant?"

You're welcome!

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