iStock / Chloe Effron
iStock / Chloe Effron

Why Are Some Farts Noisy?

iStock / Chloe Effron
iStock / Chloe Effron

WHY? is our attempt to answer all the questions every little kid asks. Do you have a question? Send it to why@mentalfloss.com.

Farts can make a lot of different noises. Some farts are high and squeaky. Some explode like a machine gun. Some don’t make any noise at all. It all depends on how much gas you have in your intestines and on the muscles around the anus (the opening in your butt).

Farts happen when your body lets out gases. Some of that gas comes from air that you swallow as you are eating and breathing. Some of it is made as your body digests, or breaks down, food to turn it into energy. Millions of tiny organisms called bacteria living in your gut help with digestion too. As they do, different gases get released. Those gases move along through your large intestine until they reach its end, called the rectum. Then they come out as farts: some quiet, some loud enough to rattle the windows!

The sound of your farts is affected by how much gas has built up inside, and how fast it comes out. It also depends on how tight the sphincter (SFINK-ter) muscles are. They ring the anus and help keep it closed. All these things together cause vibrations as the gas pushes through. If the sphincter is relaxed, your fart will probably be on the quieter side—pffft! But if those muscles are tightened up (as they are when you are trying not to fart), you’re probably going to squeak, toot, rumble, or roar. 

To learn more about gut bacteria, farts, and sharing poop for health reasons, watch this video from MIT.


WHY
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Chloe Effron
Why Can Parrots Talk?
Chloe Effron
Chloe Effron

WHY? is our attempt to answer all the questions every little kid asks. Do you have a question? Send it to why@mentalfloss.com.

Did you know that birds are the only animals other than humans who can produce human language? Some species (SPEE-shees) or kinds of birds can copy sounds they hear in their environment, and even imitate a few words. Crows, mynah birds, ravens, and hummingbirds can all copy some of the sounds they hear. But the birds that are best at imitating human speech are parrots. They can learn to say hundreds of words, and they understand what some of the words mean. One amazing African Grey parrot named Einstein, who lives at the Knoxville Zoo in Tennessee, can say about 200 words. 

About half of the bird species sing. They learn these songs from other birds. They can do this because of a part of their brain called the "song system." Inside this song system is a part called the “inner core.” The inner core is essential (ee-SENT-chall) or really important to helping these birds learn how to make sounds. Parrots also have an extra part of the song system called an “outer shell.” Scientists think the outer shell helps parrots be really good at copying sounds. But they're not sure exactly how it works.  

Parrots are social animals, which means they want to fit in with the rest of their friends. In the wild, parrots usually make bird sounds because they are surrounded by other birds. But around humans, parrots often imitate human words because they see their owners as part of their new family, or “flock.” They copy human sounds to fit in with their human flock. But parrots are also really smart. African Grey parrots like Einstein are as smart as a 5-year-old human! With training, some parrots can learn the meanings of words, the names of their favorite foods, and even count up to eight.

To see and hear Einstein talk to her trainer and sing "Happy Birthday," watch this TED talk.  

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Chloe Effron
Why Are Girls' Voices Usually Higher Than Boys' Voices?
Chloe Effron
Chloe Effron

WHY? is our attempt to answer all the questions every little kid asks. Have a question? Send it to why@mentalfloss.com.

It’s all thanks to your vocal cords. These are muscles that stretch like rubber bands across your voice box, or larynx (LAIR-inks), which is located at the back of your throat. Whenever you say hello to a friend or answer a question in class, you’re using your vocal cords to speak. The size of your vocal cords is what determines your voice’s pitch, which is its level of highness or lowness.

When you speak, air pushes from your lungs through your vocal cords and out of your mouth. The air makes the vocal cords vibrate, or move back and forth really fast. Picture the strings on a guitar. The vocal cords' vibration makes sound, just like a strummed guitar does. And like guitar strings, smaller cords create a higher sound. Girls' vocal cords are usually shorter and thinner than most boys’, which is why their voices sound higher. This difference in pitch is even more noticeable in grown-up men and women.

When you get a little older, you'll experience something called puberty (PYOO-bur-tee). It's your first step towards being an adult. Boys' bodies start producing a lot of testosterone (tes-TOSS-tuh-rone). This is a hormone. It acts like a chemical messenger to different parts of the body. Testosterone tells the body to change in all sorts of ways, like making bigger muscles and growing hair in new places. It also makes a boy's vocal cords grow thicker and longer. That makes his voice sound deeper. Girls' bodies produce testosterone too, but not as much as boys' do. Their bodies also produce another hormone called estrogen (ESS-tro-jen). These hormones make girls' vocal cords get bigger during puberty, but they don't grow as big as boys'. So girls' voices sound higher.

Have you experimented with making your voice sound different? When you speak in a really low voice you’re contracting your vocal cords to make them thicker. When you talk in a really high voice you're stretching them to make them thin. Do you want to see what this looks like? Stretch a thick rubber band and pluck it. What does it sound like? Now stretch a thin rubber band. I bet it sounds different! 

For further reading on your voice and how it changes, visit Kids Health

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