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Ask Dr. Universe

Dr. Universe: Why do we need to eat and drink? -Victoria, 7, MN

Just like a car needs gas to run, food is the body’s fuel. Food gives us energy, or the power to do work. It helps us run, jump, think, and do all kinds of things. That’s what I found out from my friend Alice Ma, a dietician at Washington State University. When you take a bite of food it goes down your throat, or esophagus, and down into your stomach. In the stomach and small intestine, things like bile, acid, and enzymes help digest, or break down your food so your body can absorb the parts it needs. Read More ...

Dr. Universe: What are bees’ wings made of? -Natalia, 13, Kennewick, WA

Dear Natalia, Bee wings may be small, but they are really strong. I learned all about bee wings from my friend Melanie Kirby, a honey bee researcher at Washington State University. Kirby said you can think about bee wings as if they were a kite. If you make a kite out of thin tissue, it might rip. But if you make it out of a strong plastic film it will be stronger. Bee wings are made of a material called chitin (KITE-IN) and it’s a lot like keratin, the material that makes up your fingernails. Chitin is what makes up the wings on each side of the bee’s body. Read More ...

Dear Dr. Universe: I am wondering if birds can smell because I have chickens and have seen their nostrils! –Lila, 9, Philadelphia, PA

Birds have nostrils, or nares, on their beaks that can help them smell all kinds of things. That’s what I found out from my friend Dave Oleyar, a scientist with HawkWatch who recently taught a course on ornithology at Washington State University. He said that when an animal breathes air, they can also breathe in different scents or combinations of molecules. The nose has receptors that pick up on scents and send information to the brain, including a part called an olfactory bulb. It’s all part of the olfactory system. You have an olfactory system, too. This system can help animals navigate the world through a sense of smell. Read More ...

Dr. Universe: Why do some birds cheep loudly while other birds cheep quietly? -Traver, 4, Indiana 

That’s a great observation. Birds make all kinds of sounds and for lots of different reasons. When I got your question, I called up my friend Jessica Tir, a graduate student at Washington State University who studies songbirds. She said one of the main reasons a bird will make a loud sound is to attract a mate. When the birds find each other, they can make a nest for their eggs and wait for babies to hatch. Read More ...

Dr. Universe: What gives leaves their shapes? Please reply back. Thanks a ton! -Pronoy, 9, San Jose, CA, USA

We can find all kinds of leaves on our planet. Just think of tiny pine needles, fern fronds, ivy vines, or a big banana leaf. My friend Eric Roalson is a professor at Washington State University who is very curious about plants. He said there are a few things that give leaves their shapes. The shape of a leaf can depend on the family history of a plant, the group it belongs to, and the environment where it grows up. Read More ...

Dr. Universe: Here is my question. How is paper made? I asked this question because there are different kinds of paper and I'm curious about how it is made. Sincerely, Sonakshi, 9, Michigan

We can make paper in lots of different ways. It often starts with trees. In fact, one of the first kinds of paper we know about was made in China using rags, plants, and bark from mulberry trees. These kinds of materials are made up of parts called fibers. Fibers are what help give plants strength to stand up. Humans who eat plants like lettuce or celery have actually eaten some of these fibers. A lot of the clothes we wear come from plant fibers, too. Plant fibers are called cellulose. Humans aren’t able to digest these fibers because they are really hard to break down. But strong fibers are great for making paper. Read More ...

Dr. Universe: Why does soap get bubbly? Samuel, 9, East Peoria, IL

When you wash your hands with soap and water, a few different things happen to make bubbles. Just like you, water and soap are made up of parts called molecules. Water molecules really like to stick together. If you’ve ever jumped in a puddle or a pool, you may have even observed how water splashes in the shape of little drops. As water sticks together, it likes to form spheres. Read More ...

How are vaccines made? - Sibagh, 7, New York City, NY

It might seem strange, but a small piece of something dangerous can protect you against something much more dangerous. This idea has been around for a long time—and it works. To learn more, I talked to Guy Palmer at Washington State University. As a scientist who studies infectious disease, Palmer likes learning about how to protect both human and animal health. Vaccines are one way to accomplish this. Read More ...

What is a tornado made of? - Alice, 6, Ames, Iowa

Dear Alice,

Have you ever felt a warm wind blow by you, followed by a cold gust of air? You can’t see it, but you can sense it on your skin. Invisible to you, winds mix together.

Usually, these winds are harmless. But under the right conditions, they can also be the main ingredients for a tornado.

To learn more, I chatted with Jon Contezac, Craig Oswald, and Joe Zagrodnik, a team of Washington State University scientists who are very curious about the weather.

To make a tornado, they explained, you need two big things: rising air and rotating air.

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Dr. Universe: Why do we have spines? - Jessie, 10, Covina, Calif.

Dear Jessie,

Your spine is more than just a long line of bones. It’s the secret to jumping for joy, the base for all your best dance moves. Every time you run, climb, walk, and play, your spine is right there with you.

“Without a spine, our ability to move would be completely different,” Edward Johnson said.  Johnson teaches Human Anatomy in the School of Biological Sciences at Washington State University. He is very curious about how all the parts of your body work together.

All creatures with spines are called “vertebrates,” including humans. They get this name from their vertebrae: the special bones that make up the spine. Your vertebrae are different shapes and sizes, but they all connect together.

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Dr. Universe: What is inside a blade of grass and why is it green? Green is my favorite color. We really like reading your articles in our newspaper. – Luke, 5, Ogden, Utah

Dear Luke,

I’ve been wondering the same thing lately.  Every time I go on walks, I notice new splashes of color. Watching bugs in the grass, I pretend they’re crawling through a jungle. Everything is bright and bursting with green.

When I saw your question, I knew Michael Neff would know the answer. Green is his favorite color, too. (In fact, when we talked over video, he wore a green Hawaiian shirt.) Neff researches plants at Washington State University, and he is especially curious about grasses.

If you chopped a piece of grass and looked at it with your eyes alone, you might not see much. But if you looked at it under a microscope, you’d see tiny structures containing even tinier parts.

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How does the Internet actually work? I know you can type in most anything and it just pops up and all that, but how? - Eden, 8, Oregon

Dear Eden,

If you wrote me a physical letter, it would take a few days to reach me. You put the letter in your mailbox. A postal worker picks it up. Then it travels between different post offices on its journey from you to me.

But within seconds of you sending this question over the Internet, it was sitting in my inbox. How can this be?

The whole Internet works like the mail system—but much faster. That’s what I learned from Adam Hahn, an Assistant Professor of Computer Science at Washington State University.

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Why are carrots orange? - Caden, 11, N.C.

Dear Caden,

When you picture the carrot section at a grocery store in the United States, you probably imagine rows of orange. But carrots can come in a rainbow of other colors: purple, yellow, red, and more.

And the first carrots weren’t orange at all. They were stark white.

That’s what I learned from Tim Waters, a Vegetable Specialist at Washington State University-Extension. He studies how to grow different kinds of vegetables, and helps others learn how to grow them too.

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How do viruses form? Since the coronavirus has been all over the news, I've been wondering this question for a long time. - Samantha, 12, N.C.

Dear Samantha,

Viruses are strange things. They’re not alive like you or me. But they behave somewhat that way—spreading, growing, appearing in new forms. How can this be?

There’s a lot scientists don’t know yet about the new coronavirus. But they do know a lot about how viruses work and make people sick.

To learn more, I talked to Sylvia Omulo, a scientist specializing in infectious diseases at Washington State University.

Read More ...

Dr. Universe: how do sleeping darts work? (e.g. for elephants) - Jonathan, 7, Pullman, Wash.

Dear Jonathan,

Some people get nervous when they go to the doctor. Maybe you’re one of them. You may not enjoy all of the visit, but you understand the doctor wants to help you. (And that a treat might await you at the end.)

But if an elephant gets sick, they can’t understand a doctor’s words. They may get confused and scared, until it’s too dangerous to help them.

That’s why sleeping darts—also known as tranquilizer darts—help so much.

“It’s safer for both the humans and the elephant because the humans aren’t right next to a wild animal, and the animal isn’t being chased to try to catch it,” Dr. Tamara Grubb said. She is a veterinarian at Washington State University who specializes in anesthesiology, drugs that make animals calm, sleepy, or unable to feel pain.

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Why do I like buffalo wings and not broccoli? - Joe, 10, New York City, NY

Dear Joe,

You’re not alone—cats don’t like broccoli much either. As a carnivore, I think a nice, meaty buffalo wing sounds great.

But humans are omnivores, meaning they eat both plants and meat. They’ve developed a taste for all kinds of things growing and living all over the world. So where do individual people’s preferences come from?

To find out, I visited Carolyn Ross, a professor of Food Science at Washington State University. Like you, she is very curious about why people like the foods they like.

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How do you make submarines? - Luke, 5, Western Washington

Dear Luke,

The next time you’re in the bathtub, turn a cup upside down on the water. Push down on it as hard as you can. See if you can get it to sink below the water.

It’ll be difficult to do! The air inside the cup makes it lighter than the water. But what happens if you turn the cup on its side, allowing water to rush in? You’ll see it’s easier to push underwater.

Those same basic forces make a submarine work.

That’s what I learned from Ian Richardson, an engineer at Washington State University. He is very curious about how liquids and solids interact. He has even helped NASA work on a submarine to someday go to Titan, one of Saturn’s moons.

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How was popcorn discovered? - Jalen, 12, Benson, N.C.

Dear Jalen,

There’s nothing like popcorn in progress: the snapping kernels, the warm buttery smell, and the knowledge that a delicious snack will be ready in minutes. It gives you some good time to think and wonder: how did humans first start doing this?

To find out where popcorn came from, I visited my friend Erin Thornton, an archaeologist at Washington State University. Archaeologists study how humans lived in the past—including the things they ate.

To learn the story of popcorn, we have to trace the history of maize.

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What is a sinkhole? What causes one? - Kathrine, 12, Calgary, Canada

Dear Kathrine,

Sinkholes can be scary to think about. They don’t happen too often, but when they do, they can take people by surprise. The solid ground disappears, and a hole suddenly appears.

It might seem like sinkholes appear out of nowhere. But they actually need specific conditions to form.

To have a sinkhole, you first must have a cave.

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How are seashells formed? And why are they different colors? Can seashells live or die? - Caroline, 9, Crestwood, Ky.

Dear Caroline,

Seashells come in an astounding variety. Some are curved and round, others long and tube-like. Some are smooth, others bumpy. Some are large, others small. Plus, they come in a rainbow of colors: red, green, brown, purple, pink, and more.

All that variety comes from the same source: little animals called mollusks, with a mighty muscle called a mantle.

I found out all about them from my friend Richelle Tanner, a scientist at Washington State University. She is very curious about the ocean and knows a lot about mollusks, a type of animal with a soft, moist body.

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Where does the universe end? - Oriah, 8, Pullman

Dear Oriah,

When you look up at the night sky, it can feel like the universe is a big blanket of stars above you. But unlike a blanket, the universe doesn’t have corners and edges. Far beyond what humans can see, the universe keeps going. As far as humans know, it never stops.

When I saw your question, I went straight to my friend Michael Allen to learn more. He is a Senior Instructor of Physics and Astronomy at Washington State University.

The universe is bigger than the biggest thing you’ve ever seen. It’s bigger than the biggest thing this cat can imagine. It’s so big that even your question has more than one very big answer.

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Why are bears called bears when they can be called anything else, not just a bear? - Natallia, 8, Yakima, Wash.

Dear Natallia,

You’ve noticed something very important: there’s no natural reason for the words humans use. Any sound could be used to describe a big mammal that eats berries and salmon.

But people who speak English choose “bear.” People who speak Spanish use “oso.” People who speak Maricopa say “maxwet.” They’re all different, but they’re all correct.

That’s what I learned from my friend Lynn Gordon, a linguist at Washington State University.

“Why do we call bears ‘bears’?” she said. “Because we’ve agreed to.”

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Dr. Universe: Why do people have different fingerprints? - Mary, 12, South Carolina

Dear Mary,

Did you know even identical twins have different fingerprints? It can be hard to tell twins apart, but a close look at their fingertips can reveal who’s who. The reason lies partly in their genes, but mostly from the unique way everyone’s skin grows before birth.

That’s what I learned from my friend David M. Conley, a professor at Washington State University’s Elson S. Floyd College of Medicine.

“The reason fingerprints are unique is the same reason individual humans are unique,” Conley said. “Variation is the norm, not the exception.”

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Why won’t a female sea turtle lay her eggs in the ocean? How do baby turtles know where the ocean is when they hatch from their eggs? - Jasmine and Shereen, 8, Gainesville, Fla.

Dear Jasmine and Shereen,

Sea turtles spend almost their entire lives in the ocean. Even as babies, sea turtles’ bodies have special traits for living at sea, helping them glide and paddle through the water. After emerging from their eggs, baby sea turtles (called “hatchlings”) scramble to the ocean to live the rest of their lives. Only female sea turtles return to land as adults, to lay eggs and begin the cycle again.

I talked with my friend Frank Paladino to learn more about sea turtles. He completed his Ph.D. at Washington State University. Today he is a professor at Purdue University-Fort Wayne and former president of the International Sea Turtle Society. He is especially interested in leatherbacks, the largest living turtle.

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Dr. Universe: Why does the wind blow? -Odin, 7, Mt. Vernon, Wash.

Dear Odin,

When the wind blows, it can do all kinds of things. It can help pick up tiny seeds and carry them away, so plants and flowers can grow in new places. It can push a big sailboat across an ocean. We can even harness the wind to make clean energy to power our homes and schools.

That’s what I found out from my friend Gordon Taub, an engineer at Washington State University. He is very curious about wind energy and told me more about why the wind blows.

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Dr. Universe: Why are brains mushy? – First Graders, Waller Road Elementary, Puyallup, Wash.

Dear First Graders,

You’re right, brains are quite mushy. It turns out the three-pound organ between your ears is mostly made up of water and fat.

I found out all about brains from my friend Jim Peters, a neuroscientist at Washington State University.

“It’s gooey. It really is squishy,” he said. “When it is warm, it is kind of like butter.”

Read More ...

Dr. Universe: Do trees still create oxygen and clean the air after their leaves fall off? – Nova, 8, Palouse, Wash.

Dear Nova,

The trees that lose their leaves in fall, such as chestnuts, oaks, aspens, and maples, are called deciduous trees. Once they lose their leaves, most aren’t able to take in carbon dioxide gas from the air or produce any oxygen.

That’s what I found out from my friend Kevin Zobrist, a professor of forestry at Washington State University.

“Don’t fret, though,” Zobrist said. “For they more than make up for it in the summer.”

Read More ...

Dr. Universe: Do babies have ways of communicating? –Jalen, 12, North Carolina

Dear Jalen, Babies can communicate in a few different ways. For the most part, they use their emotions. Humans come into the world crying, but that’s actually a good thing. In a way, babies start communicating from the moment they are born. Of course, it can be hard for their caregivers to know exactly what they mean with all those cries. Read More ...

Dr. Universe: How do you make a snow globe? – Alexa, 10, Salem, MO

Dear Alexa, If you have a long winter break ahead and are looking for a great way to spend the afternoon, you might just want to make your very own snow globe. There are a few different ways to build a snow globe, but the first thing you’ll need is the perfect container. To make a small snow globe, you might use something like an empty baby food jar. Or maybe if you want to make a bigger snow globe, you could choose an empty spaghetti sauce jar. Read More ...

Dr. Universe: Why are evergreen trees green all year? – Emily, 10, Silverdale, Wash.

Whenever I go for a hike in the woods, I can’t help but admire the tall evergreen trees. No matter what time of year it is, the pines, hemlocks, cedars, and spruces are usually all green. My friend Bert Cregg is also very curious about the lives of trees. He graduated from Washington State University and is a professor at Michigan State University. Read More ...

Dr. Universe: Why do microwaves hum? – T.J., Middle School, Ohio

Dear T.J.,

Long before humans invented microwave ovens, they had to rely on stoves or an open flame to heat up their food.

These days, we can warm up food in a matter of minutes, or even seconds. A lot of parts had to be invented to make that all happen. These parts help electricity flow through the microwave in lots of different ways.

One part called a transformer helps move the electricity from one area to another. As it does so, it may vibrate or shake a little, and that tiny movement can cause a humming noise.

Electricity is actually a big part of … » More …

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Dear Dr. Universe: How do people name continents or places on earth? Thank you. - Lila Grace, 8, Virginia

Our world is full of so many different places. They get their names in lots of different ways. One way a place might get a name is from the person who explored it. The Americas are named after an Italian explorer, Amerigo Vespucci. But Amerigo wasn’t the first person to explore these continents. There were already people living there when he arrived. Still, “America” was named after Amerigo. For the most part, people name things because they are claiming possession of a place. Because of that, sometimes the original names of places are lost or erased. That’s what I found out from my friend Theresa Jordan, a history professor who teaches a geography course at Washington State University. Read More ...

Dr. Universe: How do cows make milk? How do humans get milk from a cow? – John, 4, Colton, Ore.  

Quite a few things have to happen for a cow to make milk. First, the cow has to eat lots of food, such as hay, grass, or grain. You may have heard that a cow will regurgitate her food, or sort of spit it up, and then chew on it again.   A cow will chew this mashed up food, or her cud, so she can get all the good stuff out of it—protein, sugar, fat, vitamins, and other nutrients. Milk is actually mostly water, plus those good nutrients.   Read More ...

Why do we have eyebrows? -Zach, 11, Kettle Falls, Wash.

Dear Zach, Humans have hair on their heads, arms, and as you mention, even the face. If you feel your face, you might feel some small, fuzzy hairs on your cheeks and forehead. But the hair of your eyebrows is usually a bit thicker. I asked my friend Mark Mansperger why we have eyebrows. He’s an anthropologist at Washington State University. Eyebrows appear to serve two main purposes, he said. One of the purposes of eyebrows is to keep things like rain or sweat from rolling down your forehead and into your eyes. “It guards your eyes in that way,” Mansperger says. Read More ...

Dr. Universe: Why does the moon have phases? – Manahil, 14, Pakistan

When astronomers looked at the night sky long ago, they also wondered about questions just like this one. You know, I was also curious about why the moon looks so different at different times of the month. I visited with my friend Jose Vazquez, an astronomer at Washington State University, to learn more about it. He said that the way the moon looks to us has to do with two other objects in our solar system: our sun and earth. Read More ...

How To Properly Wear A Face Mask

Hey cool cats. I’m Dr. Universe. Whenever I go out and about, I make sure to wear my face mask. One way that germs enter the body is through the nose and mouth. The mouth and nose are interconnected. That’s why it’s so important that my face mask covers them both. I clean my hands before and after handling the mask and to avoid exposure to germs, I don’t want to touch the front of the mask. When I take off the mask, I use the loops or ties. When worn properly, this little piece of fabric can help make a big difference. We can all do our part to stay safe and healthy.

How To Properly Wash Your Hands

Hey cool cats, I’m Dr. Universe. When I come home from exploring, I always wash my hands. It takes about 20 seconds. I use soap and water. To keep track of time, I sing my ABCs. It’s important to wash the hands between the fingers and under the nails, anywhere germs might be hiding. I also wash up before making food, eating, using the bathroom, or touching my ears, nose, or mouth, places where germs can enter the body. With a little soap, water, and maybe even a song, we can all do our part to stay safe and healthy.

What does social distancing mean?

Hey cool cats, I’m Dr. Universe. When I run errands or explore the outdoors, I make sure to practice social distancing. That means keeping at least six feet of distance between me and others who do not live in my house. How wide is six feet? The length of a female lion, The wingspan of a bald eagle, or about three cats. It’s important to social distance because germs can spread from person-to-person. That’s why I like to give my neighbors plenty of space on the sidewalk and in the grocery store aisle. We can all do our part to stay safe and healthy.

Dr. Universe: My mom says video games and too much TV rot my brain. What does that mean? How does that happen? Does my brain turn to slime? – Tree Family Kids, 3, 5, 7, Dundee, Michigan

If you play video games or watch too much television, you don’t have to worry about your brain actually turning to slime. But it is true that some video games and television shows can take away some of your energy without giving you much in return. When we are not being active with our bodies, too much screen time can wear us down. It not only wears down the brain, but also the body. And at the same time, some video games and stories can often help us learn better. That’s what I found out from my friend Jonah Firestone, a researcher at Washington State University who knows a lot about virtual reality, video games, and learning. Read More ...

Dr. Universe: What does it mean to go brain dead? – Noelle, 10, Sumner, WA

Let’s say we wanted to find out what kind of electrical activity was happening inside your brain at this very moment. Yep, you read that right: your brain is full of electricity. It actually generates enough electricity to power a lightbulb. In fact, the tiny cells in your body use electricity to send messages to each other. That’s part of what helps the brain and body communicate. I decided to visit my friend Samantha Gizerian, a neuroscientist at Washington State University, to find out more about our brains. She said if we wanted to observe activity in a human brain, we could do a test called an electroencephalogram (uh-lek-trow-uhn-seh-ful-luh-gram), or EEG for short. We’d attach some small discs with thin wires, or electrodes, to a person’s head. Read More ...

Dr. Universe: If snakes smell with their tongues, what do they do with their noses? – A.J., 5, Kennewick, WA

You’re right, snakes have an amazing sense of smell. They can use their tongues to pick up on all kinds of scents in the air. Whenever we smell something in the air, we are actually sniffing tiny building blocks called molecules. These molecules are what make up the scents of everything around us—things like baked bread, fresh-cut grass, and warm cookies. If you were a snake, you might sniff out the scent of a slug or mouse. You’d use your tongue to pull the molecules from the air into your mouth. Read More ...

Dr. Universe: Why do we have a tailbone? -Tyler, 15, East Liverpool, England

Dear Tyler,

At the very bottom of the human spine is a bone that sticks out a bit called the coccyx (cox-ix). We sometimes call it the “tailbone,” but it is actually made up of several different spinal bones.

In some animals that actually have tails, those different bones at the bottom of the spine help them move their tail around. But in humans, those bones partially fused together.

Read More ...

Dr. Universe: Why do we have nightmares? -Kourtney, California,  10

You are running through the woods and a bear is chasing you, when all of a sudden you wake up in your bed and realize it was just a scary dream. Our nightmares can sometimes feel super scary, even if what’s happening isn’t real. Fear is a natural part of being a human. In fact, you may have even felt shaky or sweaty after waking up from a bad dream. It’s all part of something we call the fight or flight response. When humans are faced with something scary, this response helps them decide if they should face their fears and fight or run away by taking flight. This fight or flight response works even when you are asleep. Read More ...

Dr. Universe: Why do people like different kinds of music? – Skyler, 14, Michigan

Dear Skyler, When I got your question, it was music to my ears. Humans have been experimenting with all kinds of sounds, lyrics, and instruments for thousands of years. There are hundreds of genres of music, so while you might like one kind, a friend might like something completely different. Or maybe you became friends because of your similar taste in music. My friend Horace Alexander Young is a musician and professor at Washington State University. When I went to visit him, he had been practicing his saxophone and offered to help out with an answer to your question. Read More ...

Dr. Universe: How did the first horse change into the horses of today? -Ava, 7, Kennewick, Wash.

We can learn a lot about animals of the past from fossils, the imprints or remains we find in rocks. One fossil found in the Bighorn Basin, Wyoming helped us learn about the oldest known horses. These horses are called Sifrhippus (siff-RIP-us). They had four toes on each foot and were very small. Believe it or not, these tiny horses weighed only about ten pounds. That’s just a bit heavier than your average house cat. According to the fossil records, Sifrhippus lived somewhere between 54 and 30 million years ago. When I went to visit my friend Lane Wallett, she told me all about the history of horses. As a veterinarian and a paleontologist at Washington State University, she is very curious about both horses and fossils. Read More ...

Dr. Universe: Why do people have different accents? Why do we have them and need them? -Florrie P., 9, UK

Whether you say hello, ‘ello, hey ya’ll, toe-may-toe or toe-ma-toe, we all have a kind of accent that often comes from where we live or who lives around us. That’s what I found out from my friend Nancy Bell, a Washington State University professor who is really curious about the way language works. She told me more about why we have accents and why we need them. There are a lot of different accents. You might have friends who speak English but have a Scottish, Irish, Australian, or French accent. Even in the U.S., there are many accents from the east to the west to the mid-west to the south. In those regions, people also speak many types of English such as Chicano English, African American English, or Indian English. Read More ...

Dr. Universe: How do trees help the air? – Ella, 12

Take a big, deep breath. As you inhale and exhale, you can probably feel the air taking up space in your lungs. The air we breathe is made up of a few different things. It includes gases such as nitrogen, oxygen, and carbon dioxide—just to name a few. Animals breathe in oxygen and breathe out carbon dioxide. But in the plant world, it’s the opposite. Trees, plants, and even algae in the ocean, take in carbon dioxide from the air and, using the energy of the sun, transform it into the oxygen we all breathe. Read More ...

Dear Dr. Universe: How do we talk? – Emmy, 7, Wash. State

Dear Emmy, When you were a little kid, maybe you played Peek-a-Boo or sang “Itsy Bitsy Spider.” These kinds of games and songs have a lot of the different sounds we make when we are first developing speech. A lot of humans start out playing with speech through cooing and crying. At about six months old, this cooing and crying turns to babbling. A baby might make sounds such as ma-ma, pa-pa, or ba-ba. Read More ...

Dr. Universe: Why are dogs important to humans? Stephani R., 9, Washington State

Dear Stephani, Dogs are important to humans in all kinds of ways. The connection between the two goes back thousands of years. A long time ago, wolves would trail along after humans on hunting trips and eat any scraps they could find. Eventually these wolves evolved into dogs that helped protect the hunters and gatherers. Read More ...

Dr. Universe: How do bags form under your eyes? –Sophia Ivy, 7, New Providence, NJ

Dear Sophia Ivy, If you’ve ever stayed up late and woke up really early, you may have noticed a little puffiness or swelling under your eyes. When I asked my friend Devon Hansen about the answer to your question, she said that we first have to know a bit about how sleep works. Read More ...

Dr. Universe: What are shooting stars made of? – Erin, 11, Arkansas

If you are anything like me, you probably like watching for shooting stars in the night sky. A shooting star, or a meteor, is usually a small rock that falls into Earth’s atmosphere. When I went to visit my friend Michael Allen, a senior instructor of astronomy and physics at Washington State University, he told me a lot of shooting stars are no bigger than a pencil eraser. Read More ...

Dr. Universe: Why can’t sea turtles pull back into their shell? I was at the Saint Louis Zoo and they said tortoises and other turtles can pull back into their shells. – Tyler, 7, Missouri

There are more than 350 species of turtles that live on our planet. While many of these turtles live on land, others live in the sea. Depending on where a turtle lives, its body will be a little different. Turtles have adapted to live in different environments and they have traits that help them survive in those places. As you mentioned, a lot of turtles and tortoises on land have the ability to pull, or retract, their head into their body. Read More ...

Dr. Universe: Why do we sneeze? -Nyuma, 10, North Carolina

Imagine you are home sick from school or are just playing outside when all of a sudden—ah-ah-ah-choo! It might seem like that sneeze came out of nowhere, but a lot of things went on in the brain and body to make it happen. That’s what I found out from my friend Hans Haverkamp, a scientist at Washington State University who is really curious about the human body and how it works. Read More ...

Dr. Universe: How does the moon glow? -Reece, Pullman, Wash.

Our moon is one of the brightest objects in the night sky. But unlike a lamp or our sun, the moon doesn’t produce its own light. Light can travel in lots of different ways. Moonlight is actually sunlight that shines on the moon and bounces off. The light reflects off old volcanoes, craters, and lava flows on the moon’s surface. Read More ...

Dr. Universe: What’s the best story ever made in the world? – Jada, 13, New Jersey

Humans have been telling stories for thousands of years. At first, they told these stories out loud, then they started to write. There are more than a hundred million published books on our planet now and to find out which one is best, I visited my friend Matthew Jockers. He’s a professor at Washington State University who combines his love of stories with computer science to research what makes some books bestsellers. Read More ...

Dr. Universe: Back when cell phones weren’t a thing, how could you place a call from across the ocean? Were there wires under the ocean? -Tali, 9, Seattle, Wash.

Long before telephones, if you wanted to say “hi” to friend across the ocean you’d probably write them a letter and send it over on a ship. But in the last hundred years or so, we’ve been able to connect across the ocean much faster. And yes, it often required thousands of miles of wires, or cables, deep in the sea. That’s what I found out from my friend Bob Olsen, a professor of electrical engineering at Washington State University, who told me all about the telephone. Read More ...

Dr. Universe: Why do people litter? – Jenny, 11, California

There is a lot of litter on our planet, but it hasn’t always been that way. For most of human history, people made stuff out of things they found in nature. They might make tools out of rocks or sticks. These things break down and become part of the soil again. It wasn’t until the invention of new materials, like plastic, that we started creating more litter. In fact, along with the rise of these new materials came the word “litterbug.” Read More ...

Dear Dr. Universe: Why do we dance? – Helen H., 11, California

If we traveled around the world, we would see all kinds of dancers. We might see classical ballerinas in Russia. We might see break dancers performing on the streets of New York. We might even see tango dancers in Argentina. While the exact reasons we dance remains a mystery, there are a few theories about it. That’s what I found out from my friend Ed Hagen, an anthropologist at Washington State University who has researched the roots of dance. Read More ...

Dr. Universe: How do you make mummies? -Michael, 7, Arizona

When we think of mummies, we might imagine the kind from ancient Egypt wrapped up in linen. But there are lots of ways to make mummies—and they can even form in nature. That’s what I found out from my friend Shannon Tushingham, an archaeologist at Washington State University and director of the WSU Museum of Anthropology. Read More ...

Hi Dr. Universe: Are whales smart? -Tishawnie P., 9, Massachusetts

Dear Tishawnie,

Whales can learn to do all kinds of amazing things. Humpback whales learn how to blow bubbles and work together to hunt for fish. Dolphins, a kind of toothed whale, teach their babies different sounds. It’s a kind of language the young dolphin will know for life.

But to find out just how smart whales really are, I asked my friend Enrico Pirotta, a Washington State University researcher who studies how blue whales make long journeys across the ocean.

Let’s talk intelligence

Before he revealed the answer to your question, he shared a bit more about intelligence. Usually people talk about intelligence … » More …

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Dr. Universe: How do plants know when it’s spring? -Hannah, 3

When we see little green plants sprouting up from the soil, it is indeed a sign that spring has arrived. To find out how they know to grow, or germinate, I asked my friend Camille Steber. In her U.S. Department of Agriculture lab at Washington State University, she studies the source of almost all plants: seeds. A seed holds pretty much all the information a plant needs to know how to grow. The shell that holds all the seed parts inside even contains food for the plant. But the seed is very dry and needs to sense clues from outside to know when to germinate at the right time. Read More ...

Dear Dr. Universe: How do lasers work? -Manna, 12, India

Dear Manna,

Humans use lasers for everything from scanning barcodes and putting on light shows to performing delicate eye surgery and measuring the distances between objects in space.

Cats also like to chase lasers, but I wasn’t sure how they worked. I asked my friend Chris Keane, a physics professor at Washington State University. Keane came to WSU from the National Ignition Facility at Lawrence Livermore National Laboratory where he helped work on a laser as big as a football stadium.

The light we see

First, we have to know a bit about light. Whether it’s light from our sun or your flashlight, … » More …

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Dear Dr. Universe: I have a question for you. Why do you get dizzy when you read on the road? -Rebecca, 10

Without even thinking about it, humans can use their eyes, ears, sense of touch, and brain to keep their balance. But sometimes these senses get a little mixed up. Imagine you are in the car reading your favorite book. All of a sudden the road starts winding. As you look down at your book, your eyes focus on the pages. The book doesn’t appear to be moving, so the eyes send a signal to your brain that you could be sitting still. At the same time, something is stirring in your inner ears. Lots of tiny little hairs called cilium are inside your ears doing an important job. They help you sense how your head is moving in the world. Read More ...

Dr. Universe: What can I do to help stop ocean pollution? -Hailey, 10

It’s great to hear you want to help our oceans. After all, they do a lot for us. Life in the ocean provides much of the oxygen we breathe and is also a source of food for many animals, including humans. One of the most important things we can do to prevent more pollution is to keep our garbage, especially plastic, out of the ocean. That’s what I found out from my friend Richelle Tanner, a marine biologist and researcher at Washington State University. While a lot of plastic ends up in the ocean, it actually started under the Earth’s surface in the form of oil, leftovers of plants and animals that died long ago. Read More ...

Dear Dr. Universe: How do houses get built? -OWL School Students, United Kingdom

Humans have built all kinds of houses throughout history. During the Ice Age, humans made their homes in big caves. A few thousand years later, people figured out how to fire up a hot oven and bake their own clay bricks. A lot of the first houses made of these bricks didn’t even have front doors. To get in the house, you climbed up a ladder to the roof and used another ladder to get down inside. “As soon as humans left their caves and started settling in cities, architecture has been with us,” said my friend Mona Ghandi. Read More ...

Dear Dr. Universe: Why do flowers smell so nice? – Miles, 5

Flowers not only smell nice to humans, but also to many insects and birds who help the flowers do a really important job. Let’s imagine that you are a bee or a butterfly. You don’t have a nose on your face, but instead use your two antennae to smell things. As you fly around, you catch a whiff of chemicals floating in the air. Down below, you see a field of daisies. The flowers are releasing some chemicals, which are the building blocks of a smell. Read More ...

Dr. Universe: How many peas would fit in the sun? -Keegan, 8

Our sun is so massive, you could fit more than one million earths inside of it. To find out how many peas would fit inside the biggest object in our solar system, I decided to ask my friend and mathematician Kimberly Vincent at Washington State University. Vincent and her students said that to figure out how much of something can fit inside the sun, we need to know the volume of the sun. The volume is how much space something takes up. Read More ...

Dear Dr. Universe: How many different types of plankton are there? Are there freshwater plankton? – Arielle, 11

We can find millions and millions of plankton in bodies of water all over the world—from oceans, rivers, and lakes to ponds and mud puddles. That’s what I found out from my friend Julie Zimmerman, a scientist with the Aquatic Ecology Lab at Washington State University. In the lab, researchers can use powerful microscopes to get an up-close look at these tiny creatures. Read More ...

Dr. Universe: Why do gadgets need batteries? How do they work? -Shereen and Jasmine, 8, Florida

Dear Shereen and Jasmine, Batteries can power up all kinds of gadgets. To find out how batteries work, I decided to visit my friend and materials engineer Min-Kyu Song. He makes batteries in his lab at Washington State University. As you might know, materials are made up of atoms—and atoms have tiny parts called electrons. If you’ve ever felt a spark when you touched a doorknob, you’ve felt electrons making the jump from your body to the door. Read More ...

Dr. Universe: Why do we get phobias? -Ryan, 13, Hillarys, Western Australia

We all experience fear in our lives. It is a useful tool that helps humans and other animals survive. I happen to be afraid of dogs, thunderstorms, and water. But fears are quite different from phobias. A phobia is an intense fear of an object or situation, often one that you actually don’t need to fear. It can create a lot of anxiety. It can cause your heart rate to speed up, make it hard to breathe, and trigger nervousness, vomiting, sweating, or dizziness. Read More ...

Dr. Universe: Why do we get morning breath? -Stephanie, 10

Dear Stephanie, If you’ve ever caught a whiff of someone’s stinky morning breath, or even your own, you know it can be pretty rotten. We can trace the smell back to tiny culprits that live in our mouths. They are called microbes and they live around your gums, between your teeth, and on your tongue. Read More ...

Dr. Universe: What’s inside a sheep’s brain? – Aiden, 11

A sheep brain is about the size of a human fist and is squishy like Jell-O. In some ways, a sheep brain is very similar to a human brain. In other ways, it is quite different. I learned about sheep brains from my friend Craig McConnel, a researcher at Washington State University who is very curious about ruminants, a group of animals that includes cattle, giraffes, deer, antelopes, and of course, sheep. Like a lot of mammal brains, a sheep brain is made up of grey and white matter. It has folds and grooves, but not quite as many as a human brain. It’s also a little smoother. Read More ...

How many bones did dinosaurs have? – Addison, 9

Before humans even had a word for dinosaur, they were digging up dinosaur bones. When one paleontologist dug up a big dinosaur leg bone, he wondered if it belonged to a giant human. A woman who dug up some large teeth wondered if they belonged to a huge iguana. Read More ...

Dr. Universe: Do fish pee? – J.P., 9 ½ , Texas

Not only do fish pee, but their pee gives other animals in the ocean what they need to survive. That’s what I found out from my friend, Cori Kane, a marine biologist at Oregon State University who got her Ph.D. at Washington State University. She knows a lot about coral reefs in our oceans. Coral reefs look like a ridge made of rock, but they are actually made up of living things. Corals need a few things to survive. They need clear, warm water, sunlight, and nutrients, a kind of food that helps them grow. There aren’t usually a lot of nutrients in water near coral reefs. Luckily, there are a lot of nutrients in fish pee—and a lot of fish in the reef. Read More ...

How do volcanoes erupt? –Miles, 10, Tampa, FL

Wherever we find a volcano on the surface of our planet, we can find the source of an eruption beneath it. That’s what I found out from my friend John Wolff, a volcanologist at Washington State University. Our planet is home to all kinds of volcanoes that erupt in different ways. Some eruptions are quiet and continuous, with a slow flow of lava. Other volcanoes erupt explosively and can spew ash and lava hundreds of feet up into the sky. All of this lava has its start underground in the form of something called magma. Wolff said that scientists used to think there were large pools of hot liquid beneath volcanoes. Now we know it isn’t quite that simple. Magma is not really a liquid, but rather a kind of sludge or slurry. It helps to think of it kind of like honey. Read More ...

Dr. Universe: What are molecules? - Jolin, 9, Maryland

A glass of water has more molecules than there are stars in the night sky. That’s what I found out from my friend Jack (Qiang) Zhang, an assistant professor of chemistry at Washington State University. “Everything around us is made up of molecules,” he said. “And while these molecules may be different, they are all made of the same things.” Those things are called atoms. Zhang told me we can think about atoms kind of like Lego blocks. Imagine that you have a pile of red Legos, yellow Legos, and blue Legos. Maybe you use them to build a tiny house, or you can use this same set of Legos to build something else like an airplane or a robot. Read More ...

Dr. Universe: What do clouds do? - Desi, 9, Maryland

If you’re anything like me, you like to watch the clouds go by in the sky. Even though some clouds might look like they are just floating around up there, they can do quite a lot for our planet. The first thing to know about clouds is they are made up of tiny water droplets, ice crystals, or a mix of both—and there are many different kinds of clouds. There are white and puffy cumulus clouds, thin and wispy cirrus clouds, and tall nimbostratus clouds that stretch high up in to the sky. Believe it or not, when you walk through fog, you are walking through a kind of cloud that’s touching the ground. Read More ...

Dr. Universe: Why do we have a belly button? – Jane, 9, Kennewick, WA

Whether you have an innie or an outie, pretty much all us mammals have a belly button. But before you had a belly button, there was actually a different bit of anatomy in its place. While you were still growing inside of your mother, a small, bendy tube on your tummy connected the two of you. This tube is how you got pretty much everything you needed to grow before you were born into the world. Read More ...

Dr. Universe: What is the most smelliest fruit in the world? -Tiana, 9

Our world is full of fruits that have all kinds of delightful smells. Maybe you’ve smelled the sweetness of watermelon, pineapple, peach, papaya, or mango. But you might also be wondering about the most stinky fruit in the world. When I got your question, I asked my friend Lydia Tymon, a plant scientist at Washington State University. The first stinky fruit she thought of was the durian, a large, round fruit that grows mostly in Southeast Asia. The fruit is about a foot wide with a greenish-brown husk that has lots of spikes on the outside. Read More ...

Dr. Universe: How fast does a bunny hop? How long does a bunny live? Can a bunny swim? How many babies does a bunny have? -Rueben, 7, Pennsylvania

Bunnies are hopping all over our planet. Some hop through snow and deserts while others hop through wetlands and woods. There are lots of different kinds of rabbits and they are all a little different. For the most part, a bunny hops, or actually runs, anywhere between 25 and 45 mph That’s even faster than most house cats can run. Rabbits are related to another group of animals called hares. Actually, rabbits and hares are in the same family, Leporidae. Hares look a lot like rabbits, but they have much bigger ears and bigger feet. Read More ...

Dr. Universe: How do earthquakes happen? -Aescli E., 10, Utah

We’ve had a lot of earthquakes on our planet this year. Maybe you’ve learned about them from the news or felt one shaking up your own neighborhood. First, it is important to know a bit about the Earth’s outer layer, or crust. The crust is made of seven big pieces called “plates.” They are about 60 miles thick and sort of float on the molten rock beneath them. That’s what I found out from my friend Sean Long, a geology professor at Washington State University who knows a lot about earthquakes. Read More ...

Dr. Universe: Why do we have five fingers and five toes? -Eli, 11, Edinburgh, Indiana

Dear Eli, While humans may be one of the few animals that can give a high five, they are one of many with five fingers and toes. Humans are part of the primate family, which also includes monkeys, apes, and even lemurs. As a member of the family, you also have fingernails instead of claws and pads on your fingertips that help with your sense of touch. Read More ...

Why does caffeine make us stay up longer? -Cooper, 12

Dear Cooper, You’re right, caffeine can help us stay awake—but only for so long. To understand exactly why it works, it helps to know about one of my favorite things: sleep. All animals need rest to stay healthy. But sometimes humans don’t get quite as much sleep as they need. They might be tired during the day or have a lot of work to do. To feel more alert, they might drink a cup of coffee, tea, or soda. These kinds of drinks contain caffeine, a chemical and stimulant that can trigger changes in the body. Read More ...

How many suns are in the universe?

Hey cool cats, I’m Dr. Universe, here to answer your baffling science questions like this one. How many suns are in the universe? The sun is actually a star, our nearest star, but there are lots of stars out there. Maybe you’ve tried counting them before. One, two, three, four, five, six, seven stars make up the big dipper. Astronomers estimate that the human eye could spot about 9,000 stars. Of course, the Earth blocks our vision so we only see about half of those in the night sky. If we use binoculars, we could see even more stars, about 200,000 of them. A small telescope can help us see more than 15 million stars and even more powerful telescopes can help us look for other galaxies which are home to even more stars. Have you ever been stargazing? What did you see in the night sky? Tell us about it sometime at Dr.Universe@wsu.edu.

Why do bees make hexagons in their hives?

Hey cool cats, I’m Dr. Universe, here to answer your baffling science questions, like this one. Why do bees make hexagons in their hives? When bees make hexagons in their hives, the six-sided shapes fit together perfectly. You know, if you think about it, other shapes wouldn’t work quite as well. Circles would leave gaps in the honeycomb. Squares and triangles wouldn’t leave gaps, but the hexagon works even better. The hexagon uses the least amount of material to hold the most weight. Bees can use these hexagons to store things. The queen bees eggs, pollen, and honey. For having never done a day of math homework in their lives, bees use some pretty creative geometry and engineering to build their headquarters. You can send your own science question to Dr. Universe at Washington State University. Visit AskDrUniverse.wsu.edu.

Do plants get sunburns?

Hey cool cats, I’m Dr. Universe here to answer your baffling science questions. Like this one, “Dear Dr. Universe, Why don’t plants get sunburns?” That’s a great observation. For as much time as plants spend outside, we don’t see too many with a sunburn. Plants need sun to grow, but not too much sun. Since they can’t move into the shade, put on a hat or sunscreen, they have their own way of staying safe in the sun. They make their own kind of sunblock. Of course, it isn’t much like the sunscreen you and I might use. Plants make their sunscreen out of a special combination of building blocks called molecules. They join together to make a compound, and block out ultraviolet light from the sun. It’s the kind of light that can cause damage to skin, or other living tissues. The compound still allows other kinds of sunlight to come through. That way, the plant can live and grow without getting fried in the sun. Send me a science question of your own at stage.web.wsu.edu/askdruniverse.

What is slime?

Hey, cool cats. I’m Dr. Universe here to answer your baffling science questions like this one. What is slime? Our world is full of slime makers. Slugs make gooey trails. Bacteria create slippery slime in pipes. Slime in your joints helps protect your bones. Slime is between a solid and a liquid. It’s a non-Newtonian fluid. You can make it right at home. Dissolve a teaspoon of borax in a cup of water. In another bowl, mix together half a cup of liquid glue and half a cup of water. Then combine everything. The glue contains long chains of molecules. We call them polymers. You might think of them like cooked spaghetti noodles that are all tangled up. If we let the noodles dry out a bit, we’d see they’d start sticking to one another. What was once a free flowing liquid is now thickened by polymers, a fun slime you can mold, bounce, twist and stretch. Send me a science question of your own at AskDrUniverse.wsu.edu.

Why is the ocean salty?

Hey cool cats, I’m Dr. Universe, here to answer your baffling science question. Like this one. Dear Dr. Universe, why is the ocean salty? If we took all of the salt from our oceans and spread it over Earth’s surface, it would be almost 500 feet high. It all starts with rocks and dirt on land. Salt is one of the many minerals in rocks. A lot of it is the kind you might sprinkle on food, sodium chloride. As you might guess, it’s made up atoms called sodium and chlorine. Water is really good at dissolving salt. You can see this in action, just by adding a little salt to a cup of water. The chemical reaction in water, pulls different parts of salt away from each other. Streams and rivers help dissolve the salts from the rock and carry it into the ocean. But not all salt stays in the ocean. Find out where it goes. Or send me a science question of your own at AskDrUniverse.wsu.edu.

Why are apples red?

Hey cool cats, I’m Dr. Universe. Here to answer your baffling science questions. Like this one. Dear Dr. Universe why are apples red? In nature different colors sometimes send a message to different plants and animals. The message might be don’t eat me as is the case of some brightly colored poisonous frogs. Other times it might be a chameleon using it’s colors to attract a mate saying hey look over here. But scientists think the apples red color might just be a way of telling hungry animals we’re delicious. Long before humans were shopping for apples at the supermarket bears were scavenging for fruit in forests. One idea is that bears are particularly attracted to red. A color that really pops against green leaves. When bears see the red fruit they eat it digest it and poop out the seeds. That way new generations of trees can grow and produce even more apples. Send me a science question of your own at AskDrUniverse.wsu.edu.