Laughter is so important to humans that we learn how to do it shortly after we figure out how to crap ourselves. Within weeks of birth, babies are laughing, even though they don't yet have the cognitive development to understand why something is funny. By the time they're 4, children are laughing about 15 times an hour.

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Usually at fart jokes. Thank goodness we've moved on.

So kids will laugh at pretty much anything, but what about producing humor themselves? In a landmark study, one researcher found that women make the same number of jokes as men -- when they're children. But around age 6, something changes; the number of jokes girls make decreases, and it never evens out again. That's because, around the time girls start school, society gives them a joking lobotomy, so to speak. Think back to elementary school. You probably had a class clown, and it was almost certainly a boy. Boys are allowed to be loud and funny and play practical jokes and be annoying little shits, and girls are encouraged to act like little ladies. And ladies sit quietly and decidedly do not draw attention to themselves through loud jokes or pranks.

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She just put the cat in there.

Which sucks, because it's just about that age that kids start to practice and understand wordplay and more advanced humor. So adult male comedians have literally been training for comedy their entire lives, while female comedians have been fighting an uphill battle since they were children just to express themselves through humor. It would be like if we as a society told girls that math was a "boy subject." Sure, some girls would grow up to be brilliant engineers, but in general the field would be dominated by-

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You know what, that is a bad example.

When a woman laughs at a joke, the reward center of her brain lights up like crazy. The reward center is the part of your brain that makes you feel good when you eat chocolate or have sex or key your ex's car. So making a woman laugh results in a hugely pleasurable experience for her, which can lead to an even more pleasurable experience for you both (and nine months later to her least pleasurable experience ever. Use a condom).

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"Wait, you're still laughing about my joke, right?"

This means that for tens of thousands of years being funny was an evolutionary benefit, and possibly a necessity, for men. Women were more likely to be interested in funny guys, so being funny meant your "pull my finger" joke could keep muddying up the gene pool for generations to come.

On the other hand, women don't use jokes to show guys they're interested; they use laughter. In other words, a woman will laugh at something she didn't find funny if she liked the guy who said it, but a guy won't necessarily reciprocate the giggles, even if he's totally into the girl with the killer knock-knock jokes.

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"'Inoperable.' Ha! That's a good one, Dr. McCutiepants."

This could be because men don't experience the same neurological reward response when they laugh at a woman's joke. Sure, they enjoy it on some level, but there isn't a biological impulse to make babies with the funny lady. In fact, it might even be the opposite, since studies show that guys don't want a funny partner. A poll of hundreds of men found that, while men want someone who has a sense of humor (so she will laugh at his jokes), most men aren't interested in bedding the next Tina Fey. Why? According to the expert: "When forced to choose between humor production and humor appreciation in potential partners, women valued humor production, whereas men valued receptivity to their own humor." Yikes, guys! The more we learn about men and their evolutionarily driven sense of humor, the more you start to sound like dicks.

So the next time you hear a man complain that women aren't funny, remind him that it's because men are pretty self-centered and egotistical in the humor department. Or don't, and cross him off your friend list for making the comment in the first place.

The fact that so many men choose being funny over being with someone who's funny is part of a wider point on jokes and gender roles. In a way, humor is a type of power. Making quips about someone, even in a nice way, is exerting a kind of control over them. And since power is something we associate with men, humor is therefore seen as more of a masculine than a feminine quality. People accept that the natural order of things is men making jokes and women laughing at them. When it's the opposite, we feel like something is wrong, even if we can't put our finger on what.

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"Yup, she's on the sauce again."

One example of this is in the business world. Humor can not only be beneficial in work situations, but also help you get a job in the first place. But there is a big difference in how people react to female bosses making a joke and male bosses making a joke. One study found that only 20 percent of jokes made by female bosses in boardroom situations elicited laughter, while a full 90 percent of jokes by male bosses did. And if you've ever heard your male boss tell a joke, you know this isn't down to the fact that most CEOs should have gone into standup comedy. Again, it comes back to a power dynamic. Laughter is a social cue that lets others around us know we got the joke and shows respect to the person who made it. Laughing when a man in a position of power makes a terrible joke is a sign acknowledging that power, but societal biases already make us slightly uncomfortable when women are in charge.

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"Hey, did they make sure to soundproof that glass ceiling?"

Add to that the fact that women making jokes instead of laughing at them seems backward to us, and it ends in silence. It doesn't actually mean that the joke wasn't funny, but the reaction reinforces to both the joker and the listener that women should avoid the whole humor thing altogether. This results in female bosses making fewer jokes, and suddenly an unfair reaction created by society becomes a self-fulfilling prophecy.

And it gets weirder -- when the participants were asked which gender they thought wrote a caption, the funnier ones were almost always assumed to be by men and the less funny ones by women. This might be expected, considering their stated bias. Even when told the name and gender of the person who wrote each caption, within a short time the participants started misattributing the funny ones to men. In other words, even when they knew that women had written some of the funniest captions, the bias that men are funnier was so ingrained that it made them misremember who had written what.

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"His joke about having his first period was so true."

All this is leading up to the obvious point: Society thinks joke writing requires a penis. (They obviously don't understand how typing works.) So if you are a funny lady, there can be a benefit in hiding that fact. There are women on this very website who write under male pseudonyms or only use their first initial. When I had my first article accepted here in 2009, I went down to the telegraph office (it was a long time ago, you see) and had a long conversation with some lady friends about whether I should put my real name in the byline. JWF (Joking While Female) not only can be an uphill battle, it can be dangerous.

In the end, I went with my real name, because I felt that if I wasn't part of the solution, I was part of the problem. Plus, Cracked wouldn't let me write under the name Dick P. Ballington the Turd.

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Esq.

Kathy wrote a very funny book, and you can buy it here and here.

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