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Your Bones Are Electric (Sometimes)

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Electricity is all around us. It’s in the wires in our walls, and in the atmosphere. It’s in our phones, our cars, and, these days, our books. But it’s also hiding in a very unexpected place: our bones.

It’s called piezoelectricity, which translates to “electricity by pressing or squeezing.” Brothers Paul-Jacques and Pierre Curie—yes, that Pierre Curie—first coined the term to describe the electricity they saw in compressed quartz and tourmaline crystals.

Basically, piezoelectricity is a way of converting mechanical energy into electricity. Pressure disrupts the balance of an object’s electrical charges. One side of a crystal takes on a positive charge, and the other side becomes negative, which makes it a sort of microscopic battery.

This doesn’t work on everything (stop squeezing your cat, please), only certain crystals. But you’d be surprised how many things those crystals make up, and how useful they can be. 

Piezoelectricity is the force that allows voice recognition software to turn sound waves into signals your computer can use. It’s the reason quartz watches are so accurate, and the force that transforms the grooves on a vinyl LP into music we can hear. We can thank piezoelectricity for cigarette lighters, microphones, gas grills, ultrasound technology, and even potato guns. But its effects don’t stop with appliances; piezoelectricity has been found in all kinds of organic materials, from silk and wood to arteries, tendons, and bone. 

Yes, you have crystals in your bones. Our skeletons are made of both hard and soft tissue. The rigid parts that hold us up are composed of crystals of calcium phosphate, also known as bone salt.

Japanese scientists first found evidence of piezoelectricity in human bone in the late 1950s. In the nearly six decades since, their experiments have been replicated and their results validated. Our bones definitely can hold a charge—and that works to our advantage. 

As it turns out, bone responds pretty well to a little jolt of electricity. Electrical stimulation encourages bones to grow and heal, a fact that’s now being exploited by orthopedic surgeons. Our bones are living, changing objects, endowing the body electric with their odd little spark.

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Animals
Why Do Female Spotted Hyenas Give Birth Through Their Pseudo-Penises?
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YouTube

At the zoo, you can sometimes tell the difference between male and female animals by noting their physical size, their behavior, and yes, their nether regions. Hyenas, however, flip the script: Not only are lady spotted hyenas bigger and meaner than their male counterparts, ruling the pack with an iron paw, they also sport what appear to be penises—shaft, scrotum, and all.

"Appear" is the key word here: These 7-inch-long phalluses don't produce sperm, so they're technically really long clitorises in disguise. But why do female hyenas have them? And do they actually have to (gulp) give birth through them? Wouldn't that hurt … a lot?

The short answers to these questions are, respectively, "We don't know," "Yes," and "OW." Longer answers can be found in this MinuteEarth video, which provides the full lowdown on hyena sex. Don't say we didn't warn you.

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science
Are Sex, Drugs, and Rock 'n' Roll Really Linked? Researchers Investigate
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Around the world, sex, drugs, and rock 'n' roll are said to go hand-in-hand. But do they? As PsyPost reports, a pair of Pennsylvania psychologists recently dove into the empirical evidence tying the three together, asking college students to talk about their drug use, sex lives, and music preferences and talents to suss out whether people who play and enjoy rock music really do have more active sex lives and drug use.

Published in the journal Human Ethnology Bulletin, the study [PDF] of 467 students relied on self-reporting, which isn't typically the most reliable evidence—people are wont to exaggerate how often they've had sex, for instance—but the survey also asked them about their desires, posing questions like "If you could, how frequently would you have sex?" It also asked about how often the students drank and what drugs they had tried in their lifetimes. They also described their musical experience and what kind of music they listened to.

The results were mixed, but the researchers identified a relationship between liking faster, "harder" music and having more sex and doing more drugs. Acoustic indie rock aficionados weren't getting quite as wild as heavy metal fans. High-tempo-music lovers were more likely to have taken hallucinogenic drugs like LSD, for example, and tended to have had more sexual partners in the previous year than people who favored slower types of music. According to the study, previous research has found that attention-seeking people are more likely to enjoy "hard" music.

The study didn't have a diverse enough group either in age or in ethnicity to really begin to make sweeping generalizations about humans, especially since college students (the participants were between 18 and 25) tend to engage in more risky behaviors in general. But this could lay the groundwork for future research into the topic. Until then, it might be more accurate to change the phrase to "sex, drugs, and heavy metal."

[h/t PsyPost]

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