... right before the Dark Power shows up and Bruce Campbell starts chainsawing everyone for no reason.

New Line Cinema
Well, OK, he may have had a legitimate reason.

But Sam Raimi certainly didn't invent the technique, and it's not limited to horror films. Here's a shot from The Lord of the Rings: The Two Towers, from right before Faramir tricks Frodo into betraying Gollum, which in turn leads to Gollum betraying the hobbitses right back (only better, because he does it with the assistance of a big-ass spider):

New Line Cinema
That's the moon. The big-ass spider comes later.

Obviously, a full moon isn't some supernatural portent of doom in the real world. Movies just use it to symbolize the fact that bad stuff is about to go down because ... well, just because.

But in Reality ...

Wait a minute, why are people so freaked out by the moon in the first place? We're talking about the most powerful natural source of light at night here -- you'd think the cultural standard would be to give the moon a nod and say, "Thanks, moon. You're all right in our book." And it's not just movies: Folklore has connected the full moon to almost everything confusing and scary throughout human history, from werewolves to gods to women's menstrual cycles. Even the word "lunacy" comes from the Latin word for "moon." Why is that?

Well, it all comes down to lions.

Jupiterimages/Photos.com/Getty Images
Kitty!

A bunch of scientists studying lion attacks in Africa discovered a weird correlation: In the days immediately following a full moon, attacks on humans spiked. They discovered that the most dangerous time for people to be out is "the active hours after sunset, particularly the day after the full moon."

Why? Because a full moon means more light, and more light means the lions' prey can see them coming and more easily avoid an attack. So the lions get really friggin' hungry when the moon is full. But after that, the moon starts to rise later, meaning more darkness in the early evening -- which is right about the time people are most likely to be cruising around, their supple butt cheeks quivering in the darkness like a pair of steaks all marinated up for a tasty lion barbecue.

Anup Shah/Photodisc/Getty Images
"No, no, girl, I'm telling you. You have to chase for a bit before you kill them. The adrenaline makes the meat so tender."

Much of the human timeline for the hundreds of thousands of years since we decided to quit dragging our knuckles on the ground has seen us living alongside nocturnal predators that wanted nothing more than to gnaw on our tastybits -- not just lions, but jaguars, tigers, leopards, big-ass spiders ... you name it. So when you look at it that way, it seems pretty reasonable that we would have developed a cultural fear of the full moon, considering that it historically meant your hunting/gathering party was about to become a re-enactment of The Ghost and the Darkness, minus the protection of a rifle or Val Kilmer's "Irish" accent.

This sometimes has the bonus effect of transforming attractive people into believable nerds, because how could anyone ever possibly love someone with less than perfect vision? That's crazy talk.

Disney/20th Century Fox/Columbia Pictures
"I wear glasses -- I'm not blind. I can see you giving me the finger."

It's common enough that the Doctor on Doctor Who has joked about how he uses his brainy-specs to make him look smarter, and it even bleeds over into real life a bit (ever heard of "fashion only" lenses?). Our best guess is that it has something to do with the fact that reading glasses are the most common type of glasses in America, and that -- even in a world where Fifty Shades of Grey exists -- the act of reading still maintains an aura of braininess.

But in Reality ...

Scientists have uncovered a link between wearing glasses and being smart, and it's not just about reading. In fact, they're not even sure why the correlation is there, but people with nearsightedness have, on average, both a higher education and a higher intelligence (which were measured in two different ways).

Jupiterimages/Comstock/Getty Images
"Are you sure, doctor? Let me see that chart, I wear glasses."

Even weirder is that the correlation is positive, and consistent: The worse your vision is, statistically speaking, the higher your intelligence, and the longer you spent in school.

The best guess scientists have is that this phenomenon is due to what they call "habitual visual exploration." People who, as infants, spend lots of time exploring the visual novelties of the world in their immediate vicinity (presumably because they can't see anything beyond their immediate vicinity) are simply more likely to grow up to be really freaking smart.

So in Erin Brockovich, Julia Roberts' character (whose name escapes us at the moment) demonstrates that she's immune to preventative security and, like, most of the law, because boobs. In Terminator 3, the Terminatrix inflates her boobs to Victoria's Secret proportions to get out of a parking ticket. The Sweetest Thing has Cameron Diaz cause a motorcycle crash via her bikini-clad ass, and (just to demonstrate that this isn't a recent development) the classic war movie The Longest Day opens with French Resistance fighters sneaking past Nazi soldiers using an attractive woman on a bike as a diversion.

20th Century Fox
"Heeeey fraulein, you wanna commit some atrocities?"

Anyway, everyone knows that this stuff is cranked up a notch for comedic purposes. In real life, it takes a little more than the mere suggestion of sex to make men completely lose their mental faculties.

But in Reality ...

No. No, it totally doesn't. In a study of men's decision-making capabilities, scientists found that men made more short-term-focused decisions when in the presence of sexy stimuli. And "sexy stimuli" can apparently refer to almost anything in any way related to a woman: If a man so much as handles a bra -- even one not currently surrounding any lady parts -- he will lose a little bit of his ability to consider the consequences of his decisions.

Wikipedia
Have you ever noticed that there's never a Victoria's Secret next to a nuclear missile silo? Now you know why.

But what's truly amazing is how broad the effects are: After scientists showed them a sexy video or allowed them to fondle some (clean, hopefully) lingerie, men were more likely to make heat-of-the-moment decisions about impulse purchases, financial gambles, even what to have for dessert. All because they were reminded what women are shaped like.

You'd probably expect the suggestion of sex to cause a man to crave instant gratification in a, you know, sex-type way, but this study seems to indicate that a man's brain only comes equipped with a single instant-gratification meter -- and even the vaguest hint of sex pegs that motherfucker, negatively impacting his decisions across the board. So just remember that the next time you find yourself staring down a parking ticket or a roving pack of Nazis, ladies.

Stockbyte/Stockbyte/Getty Images
"You were doing 70 in a school zone driving the governor's stolen convertible and your license is an expired KFC coupon. Now I'm gonna let you go with a warning ..."

As tacitly noted by Futurama, musicals are the only narrative form in which you can get away with having characters straight up tell you their emotions. In Les Miserables, for example, after watching Fantine suffer pretty much every degradation a person can suffer, she looks right at the camera and sings the classic ballad "Everything Is Shitty (And Can I Please Just Go Home Now?)." Who knew a movie called "The Miserable People" would be so goddamn depressing?

But it's when they throw additional characters into the mix that it gets more complicated than that, and it's actually pretty clever: When the creators want the characters to fight, they show them singing opposing melodies that don't seem to fit together, and when they want the characters to agree, they show them singing together.

Stockbyte/Stockbyte/Getty Images
Duets: Music's pick-up artist.

OK, so it seems pretty trite when you explain it like that. And it's also very silly -- The Simpsons' famous "monorail" episode mocked this when the fast-talking salesman sells the town on an expensive scam just by getting everyone to sing about it:

If getting onto the same mental wavelength as others were really as simple as firing up a catchy little ditty together, all of the world's problems could be solved with one global hippie chorus of "Kumbaya."

But in Reality ...

We've already told you about how singing with other people makes you empathize with them, but a different study pointed out that when you play a musical duet with someone, your brain waves synchronize with each other. It doesn't even matter if you're playing the same parts of the song: You can be hitting completely different notes at different times, but as long as you're grooving to the same jam (as the kids say), your brain waves will be almost identical.

Stockbyte/Stockbyte/Getty Images
"Maybe it's just the Journey we're singing, but why wouldn't people watch a show based on someone's Twitter feed?"

But perhaps the most interesting part is the difference between a leader and a follower: The person who sets the rhythm of the song has a stronger "internal synchronization" that's actually present before they even start playing. What this means is that when two people play music together, the person leading the song is unknowingly molding the other person's brain waves to match their own.

Which suddenly makes that scene from Annie where an orphan convinces FDR's cabinet to support the New Deal by making them all sing "Tomorrow" with her seem fraught with sober realism.

Columbia Pictures
But perhaps less so when Cartman sings Asia.

But that's just due to a lack of technology -- it's not an actual prediction. As we recently pointed out, aliens evolving on a different planet would have an entirely different set of circumstances to develop in and adapt to -- they would look less like humanoids and more like, say, pink clouds of gas that communicate with various forms of farting.

But in Reality ...

We don't want to completely shatter the hopes of those of you who were longing for the day when you could bang a green alien chick like Captain Kirk did. So we'll admit that, yes, there are some theories out there that when we run into aliens, they'll look a lot like us.

George Doyle/Stockbyte/Getty Images
"Shopkeep! ALL the condoms!"

For instance, here's a scientist from Cambridge Friggin' University saying that, despite the idea that evolution provides limitless opportunities, the "survival of the fittest" rule is actually pretty restrictive about, for example, how many arms you can grow and still be adept at that whole "survival" thing. He goes so far as to insist that if or when we meet aliens, they'll have eyes and walk on two legs and even share all of our shittiest personality traits, like violence and a tendency to exploit others' resources. After all, we developed all of those things for a reason.

Or you have this scientist, who's found evidence that, he claims, indicates that human life may have been sparked by amino acids found in the cores of meteorites that crashed into the Earth. He argues that those same amino acids, which contain the building blocks of all life, may have crashed on other planets as well, like interstellar artificial insemination or ... the ending of Battlestar Galactica, we guess. So everyone would be starting from the same building blocks, which means life on the next inhabited planet may possibly be made up of green, busty alien girls. They might also be giant slug monsters. It could go either way.

Stockbyte/Stockbyte/Getty Images
"Meh, I've gotten laid on worse odds."

J.F. Sargent is a workshop moderator for Cracked. He has a silly little blog and a really great Twitter.

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