Another thing these songs have in common is that they possess what Mullensiefen calls a "circular quality." Basically, they repeat themselves a lot. So if you come up with a simple, repetitive melody (adding raspy, high-chest vocals doesn't hurt), someone, somewhere will get laid to your work. Meanwhile, despite having been rated as "better than sex" by Spotify users, Mullensiefen claims that "Bohemian Rhapsody" is one of the worst songs ever for actually doing it, because it has too many sudden changes and sections that demand your attention. Plus, it's a real mood killer when both participants start yelling "Galileo!" at the top of their lungs.

Our dickish brains also seem to like songs that "have notes with longer durations but smaller pitch intervals," making them easier to sing. If a song takes no effort to sing in real life, it also takes no effort for some tiny part of your brain to repeat over and over like the guy who's had a few too many at the karaoke bar and thinks he's Billy Idol. And you can probably guess that you're likely to catch an earworm if you listen to a song all the time, but that's not all. They are also more likely to happen when you're "tired, stressed, or idle," which is naturally the ideal time for "It's A Small World After All" to start looping in your head like a skipping record player.

Thankfully, there are things you can do to get rid of an earworm that don't involve a screwdriver in your ear. Doing something related to language, like talking with someone or vainly attempting a crossword puzzle, can take up the brain resources that are used to power your head's eternal song loop function. Alternately, you could dive in and listen to the entire song a couple of times. Since you almost always have only a snippet of a song stuck in your head, listening to the whole thing helps put the earworm to rest like a vengeful ghost. At least, until some asshole says the words "We Built This City" and you-- oh, whoops. Sorry again.

Might as well give in.

But why does some music make us flip the fuck out? Because when a song brings out the animal in us, it really is bringing out the animal in us. According to researchers at UCLA, "music that shares aural characteristics with the vocalizations of distressed animals captures human attention and is uniquely arousing," and not only to perverts with animal fetishes, as you might think. You consciously know that you're listening to some dudes playing instruments on a stage, but a primal part of your brain is going, "That right there is some animal dying." It's not that hard to make the leap. The high-pitched squeal of a Jimi Hendrix guitar solo does sound a lot like a jungle cat being attacked by a pack of wild snare drums.

Which probably happened at Woodstock '99.

And what happens when an animal hears another animal in distress? They freak out. Their adrenaline spikes, and they have to choose whether to stay and fight or run like hell. Music can elicit a similar reaction in concert-goers ... but since we can't escape (the tickets were $67, dammit) or climb the stage and eat the singer, we instead reroute that energy into colliding our body with someone else's like we're trying to discover the Higgs Boson. So if the next time you go to a concert, you feel the inexplicable urge to throw feces at the stage, now you know why.

And now, for the exact opposite of this entry ...

Yes, oddly enough, tamarin monkeys find the sounds of "Of Wolf And Man" by Metallica relaxing, according to a study by the University of Wisconsin. Scientists collected 14 tamarins together and played them four songs: "Adagio For Strings" by Samuel Barber, an unnamed piano piece by Nine Inch Nails (likely this one), part of "The Grudge" by Tool, and the aforementioned Metallica ditty. They wanted to compare how the monkeys reacted to our music, as opposed to some songs specially made to remind them of animal calls. It turned out that the only human music that got a reaction was Metallica -- but instead of making them bash their heads and do devil hand signs, they calmed down.

You see, monkeys have different uses for screaming than we do. Tamarins in particular have certain cries that essentially mean, "HEY, YOU GUYS! OVER HERE! I'M RELAXED!"

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While other cries spread agitation, these ones spread calm. So when these monkeys hear music that resembles monkeys screaming in a certain way (like James Hetfield's soothing voice), they chill out. This could lead to a breakthrough in "animal husbandry guidelines," which is a more delicate way of saying "helping animals fuck." We wish Metallica all the luck in the world in their new career as the Marvin Gayes of the animal world.

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There's a clear, quantifiable difference in the music made before and after the British Invasion, meaning that everyone who says "the Beatles are overrated" is objectively full of shit. Then again, musical revolutions aren't necessarily all positive. The second one was in 1983, when music got more technology-focused and people like Eurythmics were using synthesizers to do everything, including hold interviews and answer fan mail. And the last one was the rise of rap and hip-hop in 1991, with acts like LL Cool J and Public Enemy bringing the biggest change yet. Because rap is spoken, the pop charts were suddenly filled with songs without harmonies. (They made up for it by dramatically increasing the number of instances of "motherfucker" compared to Mr. Acker Bilk, though.)

On the other hand, the study also determined which movements were the least revolutionary. Punk, for example, failed to make much of a splash in mainstream music in the '70s, while glam metal had the opposite effect -- for a while in the late '80s, everything sounded exactly the same. (Which is to say, like butts.)

If you look up the sheet music for this online, it's just poop emojis.