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Ask Dr. Universe History and Geography
University Communications Network > Ask Dr. Universe > History and Geography

Dr. Universe: How are coins made? -Dahlia, 10, Olympia, WA

In the United States, pennies, nickels, dimes, quarters, and other coins are made through the U.S. Mint. It turns out, they’ve been making a lot more coins than usual during the global pandemic. But more on that in a moment. It takes both science and art to make coins. Coins are made from metals that have been mixed together. We call these kinds of metals alloys. The very first coins in the world were made thousands of years ago in Turkey from electrum, an alloy of gold and silver. A penny is made from an alloy of copper and zinc. Read More ...

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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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 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: 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: 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 ...

Why do we have different feelings? - Charan and Aishwarya V., 10 & 8, Rutherford, New Jersey

Dear Charan and Aishwarya,

Imagine you are playing a game of soccer and your best friend is on the opposing team. The sun is out, you are having a great time, and you score the winning goal. You’d probably feel pretty happy and so would your team.

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Why is Pi 3.1415...? What if it was just 3? -anonymous

Dear Curious Readers,

It’s almost March 14. You know what that means: Pi Day, as in 3/14, or 3.14159265359 and so on.

I met up with my friend Nathan Hamlin, a mathematician and instructor here at Washington State University, to explore your question about this never-ending number.

We calculated Pi with some of my favorite items: yarn and a tuna can. You can try it at home, too.

Read More ...

Why is yawning contagious? -Grant, 10, Pullman, WA

Dear Grant,

When I got your question, I met up with my friend Hans Van Dongen, a scientist at Washington State University in Spokane. He works in a research lab where they study sleep. As a cat who appreciates naps, it’s one of my favorite places to visit.

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If mollusks have such heavy shells to drag around with them, how have they spread all over the ocean? -Michel W.

Dear Michel,

Mollusks, from land snails and slugs to oysters and mussels in the sea, have a few things in common. They have a head. They have a soft middle part that holds their organs. Then, some have a muscle that’s known as a “foot.”

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Dr. Universe, How are magnets made? -Andrea, 8, Berkeley, CA 

                                                                                   

Dear Andrea,

When I saw your question, I headed straight for the Magnetics Lab and met up with my friend John McCloy. I found out the word “magnet” comes from a Greek word for the region of modern-day Turkey we once called Magnesia. That’s where people found magnets in nature.

Read More ...