Why do we lose teeth?

From wigglers to lost teeth traditions, we're looking at all things chompers. Chew on this!


Today we’re looking at a phenomenon that happens to all of us: losing our baby teeth and getting new ones! So how do our teeth grow in and what makes them fall out? Naturally, a group of wandering teeth helps us explain. We'll also find out why we have two sets of teeth in the first place. A chatty tooth travel agent will introduce us to all the different ways to send our baby teeth off in style and we'll play a game that will test your knowledge of animal teeth. Plus, the Moment of Um answers the question "Why do bees make a buzzing sound?"

What causes wildfires?

A fire can be super useful or cozy or even magical. But it can also be dangerous -- and in the case of wildfires, if they burn long and hot enough, they can destroy ecosystems and send lots of harmful smoke into the air. 


A fire can be super useful or cozy or even magical. But it can also be dangerous -- and in the case of wildfires, if they burn long and hot enough, they can destroy ecosystems and send lots of harmful smoke into the air. 

In this episode, we're going to find out why wildfires are getting bigger and why wildfire season is lasting longer now. We'll learn how the tribes who've lived in what is now called Northern California managed the forests and kept fire in check for thousands of years, and how those practices are being used today. 

We'll hear from a friendly house about how to stay safe from smoke inside and find out how firefighters work to contain fires once they've started. 

Plus, our Moment of Um answers the question: Is the name of a letter considered a word?

Million Bazillion answers your questions about money

Today we’re sharing an episode with you from our friends at Million Bazillion, the podcast that answers the questions kids have about money. They help dollars make more sense and they’re back for a whole new season! 


We’ve got an extra special episode for you today from our friends at Million Bazillion, the podcast from Marketplace that answers the questions kids have about money. They help dollars make more sense and they’re back for a whole new season!
 
Today, hosts Jed and Bridget answer a question from two curious listeners who want to know why we pay taxes. In answering the question, they come across the legendary Robin Hood, known for his hatred of taxes. Back in his day, tax-collecting sheriffs forced people to pay money to a king, who decided how those taxes were spent. These days our tax system works a bit differently. We get to vote for people who’ll spend that money on things we care about — like schools and libraries, health care for elderly people, police, parks, sewers and so on. With the help of a rambling troubadour and a tax policy expert, Jed and Bridget teach Robin Hood that the way tax dollars are spent today reflects what we prioritize as a society. Plus, we’ll ask random kids some not-so-random questions.
 
Million Bazillion is a collaboration between Brains On and Marketplace. It’s hosted by Jed Kim and Bridget Bodnar. You can listen to more episodes here, or subscribe at Apple Podcasts, Spotify, Google Podcasts, or wherever you get your podcasts.
 

Why do mosquitoes bite? Scratching that itch

Have you been itching to find out more about mosquitoes? Check out this buzz-riffic episode all about those pesky skeeters.


In this episode, we're tackling all the mosquito questions that have been bugging our listeners. Why do they bite? Why do the bites itch? Is scratching them a good idea? Why do some people seem to be more delicious to mosquitoes? How can we keep them away from us? And are mosquitoes good for the world? The Hoax Hunters make an appearance plus the Moment of Um answers the question, "What is a solar flare?"

Why do songs get stuck in our heads?

You know that feeling where you get a snippet of a song stuck in your head and it loops over and over? Those hard to shake songs are also known as earworms, and in this episode Molly has a particularly sticky one in her brain. We'll find out why some songs are catchier than others and, most importantly, scientifically-proven ways to get rid of them. 


You know that feeling where you get a snippet of a song stuck in your head and it loops over and over? Those hard to shake songs are also known as earworms, and in this episode Molly has a particularly sticky one in her brain.

We'll find out why some songs are catchier than others and, most importantly, scientifically-proven ways to get rid of them.

Plus, we'll hear a mystery sound and a Moment of Um that answers the question: "Do spiders have bones?"

Vaccines for kids and silver linings: Our second COVID summer

Adults around the world are getting vaccinated against the coronavirus, and now, in a handful of countries (including the U.S.) kids over 12 can get vaccinated too. 

We hear from a 13-year-old who participated in a clinical trial for a vaccine and get tips for how to navigate the world when only some people in your family are able to be vaccinated. Plus, Kara and Gilly share expert advice on how to handle big feelings as the world starts to open back up. 


Adults around the world are getting vaccinated against the coronavirus, and now, in a handful of countries (including the U.S.) kids over 12 can get vaccinated too.

We hear from a 13-year-old who participated in a clinical trial for a vaccine and get tips for how to navigate the world when only some people in your family are able to be vaccinated. Plus, Kara and Gilly share expert advice on how to handle big feelings as the world starts to open back up.

And a new Moment of Um answers the question: What are eye boogers?


How do the COVID vaccines work? // Brains On! Science Podcast For Kids

Do dogs know they're dogs?

Do dogs know that they are dogs?

We treat dogs like they're part of the family. But do they know they are a different species, or do they think they're just short, four-legged people?

In this episode, canine cognition researcher Alexandra Horowitz helps us puzzle out this question. We’ll also find out what happens (or doesn’t) when a dog looks in the mirror. Dogs are always dozing, and we’ll check in to see if they are dreaming too. And, we take a quick trip around the world in the language of barks. 

All that, plus a brand new Mystery Sound and moon-filled Moment of Um.


We treat dogs like they're part of the family. But do they know they are a different species, or do they think they're just short, four-legged people?

In this episode, canine cognition scientist Alexandra Horowitz helps us puzzle out this question. We’ll also find out what happens (or doesn’t) when a dog looks in the mirror. Dogs are always dozing, and we’ll check in to see if they are dreaming too. And, we take a quick trip around the world in the language of barks.

All that, plus a brand new Mystery Sound and moon-filled Moment of Um!



We often talk about our canine pals like they have the emotions and language of people but do dogs really understand they're dogs the way that we understand we're humans? In this episode, canine cognition researcher Alexandra Horowitz helps us puzzle out this question. We’ll also find out what happens (or doesn’t) when a dog looks in the mirror. Dogs are always dozing, and we’ll check in to see if they are dreaming too. And, we take a quick trip around the world in the language of barks. All that, plus a brand new Mystery Sound and moon-filled Moment of Um!

How do dogs "see" with their noses? - Alexandra Horowitz

Our 200th episode is SUN-sational!

For our 200th episode, we get an up close and personal look at the sun. 


There’s no better way to celebrate our 200th episode than with our own shining star: the sun! In this episode we speak with Dr. Nicola Fox, who leads a team of NASA scientists that sent a probe to collect data and zoom by the sun. We also hear some great listener suggestions on what new planet could be added to our solar system. We even get a chance to check in with The Sun and her weekly broadcast, That’s Hot.

Our 200th episode wouldn’t be complete without a visit from some of our favorite pals: Bob, Gungador, Harvey and Elevator! Of course there’s a new Mystery Sound too. And the Moment of Um comes just in time for mosquito season, because it answers the question: Why do we itch?

Thank you so much for helping us make 200 episodes! We could never have done it without your questions and encouragement, and we can’t wait to make 200 more!


How NASA's Parker Solar Probe Will Survive the Sun

How far can a cloud travel?

Can the same cloud you see travel halfway across the world?


We’ve all played the “what does that cloud look like” game. Maybe you saw a bunny… or an airplane… or a unicorn. What if that same cloud also be seen by someone in a far off continent? That’s what a listener in Minnesota wondered. He wanted to know if the same cloud he saw in a park near his house could also be seen in Africa.

We talk to Deanna Hence, one of our favorite weather experts, and she tells us about how clouds travel. We also dust off the Zoom Ray to learn about what is inside of a cloud. And have you ever noticed the similarities between cloud types, like cumulonimbus, and magic spells from Harry Potter? Well, we have, and we made a game out of it!

We also have a brand new Mystery Sound for your guessing pleasure (or torture) and a Moment of Um that answers the question: Why do pugs have such scrunchy faces?  

Totally Slothsome: All about sloths

Slow moving sloths and their perma-smiles have captured the heart and minds of people everywhere. Find out what makes this slowest moving mammal tick. 


There’s more to sloths than slowness. They’re great at saving energy, hanging upside down, and swimming! In this episode, Sloth Appreciation Society founder Lucy Cooke stops by to tell us all about these amazing animals. We also get into a sloth mystery: The Case of the Perilous Poop Journey. Luckily, there’s a sloth sleuth on the case. And sloths aren’t the only animals who aren’t in a hurry — a few others show off their slowest skills.

There’s also a Mystery Sound for you to guess, and a Moment of Um: Why do ostriches stick their heads in the ground?

How do computers store so much info in such a tiny space?

Microchips are in our phones and laptops. They’re in our cars and refrigerators. They’re in our watches and vacuum cleaners. They are everywhere, but where did they come from?


If you translate “Hello! How are you?” to binary code, it looks like this: 01001000 01100101 01101100 01101100 01101111 00100001 00100000 01001000 01101111 01110111 00100000 01100001 01110010 01100101 00100000 01111001 01101111 01110101 00111111

This episode takes a look at how computers can do so much with such tiny parts. But computers weren't always small -- so we take a look at where computers came from. We visit Ada Lovelace, whose love of math and weaving paved the way for modern-day computers. And we hear about the material that let computers shrink from the size of a room to something that fits in our pockets. There’s also a visit from a yak and a ram, but you’re just going to have to listen to find out why.

All that plus a new Mystery Sound and Moment of Um that answers the question: what is the flavor of root beer?

How does taste work? We react to our very first episode!

Wow, it’s been almost 10 years since we put out our first episode about eating. We’re revisiting the episode with some behind the scenes commentary.


 Brains On has a very special milestone coming up -- it’s almost our 200th episode! To celebrate, we're re-listening to our very first episode which was all about eating. We'll play the episode and chime in with commentary to give you some behind the scenes glimpses and backstories along the way. We’ll also hear an update from our very first co-host ever -- Ian Roberts, who is now a college student and an adult. Plus a brand new Moment of Um answers the question: Why do we have birthmarks?

Like bread and cheese? Thank fungus!

Picnics wouldn’t be picnics without fungus. Bread, cheese and salami all incorporate our fungal friends!


That fuzzy sandwich in your fridge? Yeah, don't eat that kind of fungus. But the mushrooms in your stir fry? Or the yeast in your bread? Or the rind on your brie? Or the miso in your soup? All of those delicious foods are possible thanks to fungus!

In this episode, we'll learn about how our ancestors first figured it out some mushrooms were safe to eat, we'll learn about the microbes that make cheese possible, and we'll meet some fungal chefs who are key to cooking up some of our favorite foods. Plus a brand new mystery sound and a Moment of Um that answers the question: "How does rubbing two sticks together make fire?"

Is mold alive? A look at fascinating fungus

Molds and fungi have been responsible for everything from medicines to that mystery that’s been in your fridge for too long. This episode looks at how the kingdom of fungus thrives.


Fungus deserves a party because it’s everywhere and super important to life on this planet. The kingdom of fungus includes mushrooms and molds, but also yeasts, like the kinds that help make bread. So today, we’re embracing the ick, we’re snuggling up to the slimy, we’re making friends with mold and mushrooms… It’s a full on Fung-o-Rama! We'll learn about a day in the life of mold, a fungus that turns ants into zombies, and how fungi will help us in the fight against climate change. All that, plus a brand new mystery sound and a Moment of Um that answers the question: "How does air fry?"

How Mushrooms Are Turned Into Bacon And Styrofoam | World Wide Waste

Is time travel possible?

Who hasn’t dreamed of going to the past or taking a peek into the future? This episode takes a look at the ins and outs of time travel. 


Will we ever get to rewind time, or fast forward through it? Sanden stops by to tell us all about how time works. He also has a couple ideas about how we might make time travel a reality! But one tricky thing about time travel is that it’s full of paradoxes — so we look into those, too. And science fiction expert Lisa Yaszek swings by to tell us just how long humans have been thinking about time travel (hint: a really long time).Listen closely for the mystery sound, and the moment of um: how do clothes get dirty even though you can’t see it?

Mystery Sound Extravaganza 2021

How many Mystery Sounds can you guess? How many can you handle?!?


What's that you hear? That's right, It's an episode of nothing but mystery sounds! Are your ears up to the challenge? Plus, we'll hear an answer to the question: "How do squirrels find their nuts after they bury them?"
If you'd like to submit a mystery sound, you can share it with us here: brainson.org/contact
And you can support the show at brainson.org/fans
You can also buy our book, complete with Mystery Photos, at brainson.org/shop or at your favorite local bookstore

Why are smartphones so hard to put down?

Screens are everywhere these days! We’re taking a look at why smartphones are so addictive, and how our devices affect us. Our co-hosts took on a bold challenge for this episode: they went a week without phones or tablets. We’ll hear how their experiment went, then Sanden will fill us in on the brain chemical that trains us to love our screens.


Screens are everywhere these days! We’re taking a look at why smartphones are so addictive, and how our devices affect us.

Our co-hosts took on a bold challenge for this episode: they went a week without phones or tablets. We’ll hear how their experiment went, then Sanden will fill us in on the brain chemical that trains us to love our screens. We'll also learn why the predictability of messages and alerts on smartphones makes them extra hard to put down.

Plus, we’ll get a few tips from Catherine Price, the author of How to Break Up With Your Phone.

And! A new moment of Um: why are bruises blue, and how do we get them?

Screens are everywhere these days! We’re taking a look at why smartphones are so addictive, and how our devices affect us. Our co-hosts took on a bold challenge for this episode: they went a week without phones or tablets. We’ll hear how their experiment went, then Sanden will fill us in on the brain chemical that trains us to love our screens. We'll also learn why the predictability of messages and alerts on smartphones makes them extra hard to put down. Plus, we’ll get a few tips from Catherine Price, the author of How to Break Up With Your Phone. Price has more resources for screen time habits at https://phonebreakup.com/. And! A new moment of Um: why are bruises blue, and how do we get them? This episode is sponsored by "The Last Kids on Earth" by Max Brallier, available wherever books are sold, and Quip (getquip.com/brainson). You can support the show at brainson.org/donate

What did dinosaurs sound like?

New discoveries and technologies are getting us closer than ever to recreating dinosaur sounds and figuring out how they might have moved.


Did dinosaurs roar? Or meow? And how do we know? Paleontologist Julia Clarke stops by to talk about sounds T. Rex might’ve made. We know a bit more about other dino sounds, and dinosaur expert Riley Black fills us in on those. Plus, a game about dinosaur names, and a look at how dinos moved with paleontologist Jingmai O’Connor. 
Stick around for the mystery sound, and a Moment of Um that answers this head-scratcher: How does hair dye work?

Dino Edition: How do we know what dinosaurs looked like?

With new fossils and new technology, our understanding of what dinosaurs looked like is evolving. This episode tracks those changes to show a more complete dino picture.


20 years ago, we pictured dinosaurs as green, scaly animals. But times have changed! Now, we know some dinosaurs had feathers. And who knows — maybe some even had stripes.
This episode looks at how we figure out what color dinosaurs might’ve been. We talk to Jingmai O’Connor, who studies fossil reptiles, about finding color pigment in fossils. And paleoartist Emily Willoughby talks to a “museum” about how her dino-depictions have changed over the years. 
Our co-host, Elyana, also brought us this important question: If dinosaurs evolved from birds and birds don’t fart, did dinosaurs fart? Wha-wha-what!?! Look no further than this episode for an extensive investigation.
Remember to keep your ears open for the brand new Mystery Sound. And break out your kilns, because today’s Moment of Um answers this question: How do you make clay for pottery?
There’s so much dino-tastic information that we decided to make a second dinosaur episode. So if you haven’t had enough (and who has?), make sure to check out next week’s show about what dinosaurs might have sounded like.

What's in the COVID vaccine?

There’s a lot of talk about the COVID vaccines, but what are they actually made of. Let’s take a peek!


In this episode, we're using our zoom ray to zoom way in and answer your questions about the COVID vaccine. What's in the COVID vaccine? How does it work? And how do they make it? We'll also look at how our fight against the new coronavirus has had a huge impact on another virus: influenza. And, we'll head to a stadium to learn what 95% effective means for a vaccine. (Warning: There are seagulls overhead!)

Plus, we'll have a brand new mystery sound and a Moment of Um that answers the question: what do scientists eat in Antarctica?

What's behind the waves and tides?

Brains On: Waves, wind, tides and moon

How does the moon control the tides? Where do waves come from? And what’s it like to live in a tide pool?


This is an encore of an episode that was originally published Aug. 30, 2016.

Sir Isaac Newton drops by and drops knowledge. He helps explain why the tides ebb and flow. Then, an oceanographer/surfer tells us where waves come from and how they get there shape - cowabunga! Plus we hear about what it's like for marine life that move to a new neighborhood once or twice a day. Sometimes it's underwater, sometimes it's not. Don't forget to hang ten with this episode's Mystery Sound.
 
Now is the time to vote for debate topics. Check out BrainsOn.org to choose a topic for Sanden and Marc to debate this fall. Everyone wins!

Why do we have crushes?

Butterflies in your stomach, blushing, that giddy feeling… why do crushes do these things to us and what can it teach us?


When you've got a crush on someone, it can feel a bit overwhelming. All of a sudden, you might have butterflies in your stomach! And maybe you find yourself acting differently than you normally would. Why does our brain do this to us anyway? In this episode, we'll answer a slew of your crush-related questions: Why do we get crushes? Why do they make you feel so many feelings? How do you decide who you have a crush on? Plus, how do you navigate all the tricky parts of crushes -- like your crush finding out you like them?

We tackle all these questions. Stick around for a Moment of Um that answers: "What would happened if it rained oobleck?"

Let's go bananas!

All your banana questions answered. How close is human DNA to a banana’s? Why do bananas change color? Where did that slipping on a banana peel joke come from? 


HARVEY, our omnipresent virtual voice assistant, gets a software update that makes him go bananas for bananas. And if we talk about anything except bananas, he turns the microphones off! We talk to geneticist Dr. Janina Jeff about how much DNA we share with a banana, find out why bananas make other fruits ripen, how bananas grow, and where that slipping on a banana peel joke came from. Speaking of jokes, we'll hear a bunch of banana jokes from listeners too! Plus: The Moment of Um answers the question: "Why are peaches fuzzy?"

You can hear more from Dr. Jeff on her podcast In Those Genes.

Slipping on a banana peel - 3 versions of the classic joke

A very super shot: All about coronavirus vaccines

People have started getting vaccinated. Here’s why that’s a good thing and why you should too.


In December, people started getting vaccinated against COVID-19. This is a huge scientific accomplishment and important step in making it safe for us to hang out in person again. So how did scientists develop this vaccine so fast? And how did they test it to make sure it's safe? And how do these mRNA vaccines work? We have answers to all your questions, plus New York Times science journalist Apoorva Mandavilli explains what scientists have found out about how long immunity lasts to this new coronavirus. And Kara and Gilly are back with a cow-side chat about herd immunity. Plus: A new mystery sound and a Moment of Um that answers the question, "What would happen if the moon fell down onto earth?"

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