Mental Floss
Mental Floss

BIG QUESTIONS

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High heels, though a staple of nearly every woman’s closet these days, aren’t exactly the most reasonably designed footwear. We wobble and slip and turn our ankles on every uneven stone, but refuse to trade them in for more sensible flats and sneakers. Wh

Caisey Robertson
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For humans, sudden gyrations of the head and neck—whether they’re from car accidents, rollercoaster rides, or chiropracty gone awry—can tear blood vessel linings in the neck, leading to clots that can cause stroke. Not so in owls, which can quickly rotate

Erin McCarthy
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Last month, the U.S. Army Corps of Engineers announced that if water in Lake Michigan drops below the level of the Chicago River, the River could reverse course and begin flowing backward to its source. Has an American river ever done an about-face like t

Matt Soniak
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Head shrinking is rumored to have occurred all over the world, but documented only among a few indigenous South American tribes living in Peru and Ecuador. How do you take a flesh-and-bone head and shrink it?

Matt Soniak
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Quack, in the sense of a medical impostor, is a shortening of the old Dutch quacksalver (spelled kwakzalver in the modern Dutch), which originally meant a person who cures with home remedies, and then came to mean one using false cures or knowledge.

Matt Soniak
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From your car, to your lawn mower, to your snow blower, to your chainsaw—the power of almost every engine you deal with is measured in terms of horsepower. None of these things seemingly have anything to do with horses, so where did that measurement come

Matt Soniak
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Humans have observed marine mammals stranding themselves on land since at least the first century CE, when the ancient Romans and Greeks recorded beaching incidents. Modern marine biologists are only able to determine the cause of a beaching about 50 perc

Matt Soniak

The smoke alarms in my apartment building are both ridiculously sensitive and ridiculously loud. They regularly go off even when there’s no smoke, and I often have to scramble up on top of a chair to reset them because a pot of boiling water is producing

Matt Soniak
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First off, popcorn isn’t just any old corn. It’s a cultivated strain of flint corn known as zea mays everta. Its kernel is also a whole grain—it consists of the bran (the hull or outer covering), the germ (the “embryo” that germinates into a plant), and t

Matt Soniak
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Fictional characters, and even real-life folks, often talk about animals and people—particularly snarling dogs and knife-wielding lunatics—being able to “smell fear” on people. No one ever seems to be able to describe just what fear smells like, though.

Matt Soniak
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Daven Hiskey runs the wildly popular interesting fact website Today I Found Out. To subscribe to his “Daily Knowledge” newsletter, click

Daven Hiskey
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Whether you’re buying them for your kids or yourself, you’ve surely noticed that Barbie dolls, action figures, and other toys often come packed in their own tiny Fort Knoxes, with layers upon layers of plastic, twist ties and tape all housed in an unbreak

Matt Soniak

Tis the season to be getting the cold and flu. But is it possible for the bacteria and viruses that infect us so easily to get sick themselves?In 1917, a microbiologist working at the Pasteur Institute in Paris discovered what he described as an invisible

Matt Soniak

Whether you end a letter or e-mail with it—or you recognize it from the end of each Gossip Girl episode—“Xoxo” is commonly known to refer to the phrase “Kisses and hugs.” But how did these two inconspicuous letters come to represent that well-known

Sean Hutchinson
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