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13m 11s

This Face Changes the Human Story

Our species is the only remaining member of the genus of upright, walking apes known as Homo. Where did we come from? Our history just got a whole lot more complicated (in a good way) thanks to some incredible new fossils unearthed in South Africa over the past few years. I got to visit them, and the scientists who discovered them, to learn their story and ours. Meet your cousin: Homo naledi.

16m 8s

How Blind People See With Sound

When Molly and I first met, we started talking about how she navigates the world, because I’m a nerd and I always steer the conversation toward science. I was not prepared for what she told me. She said she uses echolocation!

5m 55s

1 MILLION Species Could Go Extinct… Here’s Why.

A massive new study has just been released showing that human activities are threatening Earth’s other life forms in some very bad ways. One million species may be at risk of extinction. Just let that sink in. Isn’t the Anthropocene awesome? Check out the study below to learn more and find out how we can stop it.

5m 21s

Is Your Eye Color Real?

The eyes are often the first thing we see when we look at someone. And when you look at them up close, everyone’s eye color is a kaleidoscope of shapes and hues. How does eye color work? The answer involves some very cool physics, and probably isn’t what you were taught in school.

8m 35s

Why Do We Get Dizzy (…and Astronauts Don’t?)

We’ve all gotten dizzy before… but have you ever gotten WEIRD DIZZY? I teamed up with Vanessa Hill from BrainCrat to answer the question “why do we get dizzy?” and in the process we learned about some very strange and hilarious ways to get extra-special dizzy! Get ready to learn about your vestibular system, the system that lets you know where your body is in space.

6m 56s

How to be Crushed by the Atmosphere!

Air. I bet you never even notice that it’s there. Yet you are swimming in an ocean of it every day. If there’s a literal ton of air pressing down on you all the time, so why don’t we feel it? We look back at the history of physics to learn how we figured out air pressure, why vacuums don’t suck.

9m 12s

The Mystery of the World’s Greatest Butterfly Migration

The monarch butterfly migration is one of nature’s greatest events. This orange-winged wonder travels up to 4,500 km from all over North America to spend the winter hanging from oyamel fir trees in central Mexico’s mountain forests. But how does an animal with a brain the size of a poppy seed navigate to this one special place?

10m 47s

Why Are So Many People Allergic To Food?

More people have food allergies than ever before. Peanuts, tree nuts, shellfish, eggs, and even milk… the list of possibly dangerous foods seems to get longer every day. But why do some people’s bodies have deadly reactions food? And why are food allergies on the rise? In this video we explain what food allergies really are, and what the difference is between food allergy and food intolerance.

7m 13s

Where On Earth Do You Weigh The Least?

You may have heard that a kilogram of feathers weighs the same as a kilogram of steel, but that all depends on where you weigh them. This video is all about the difference between mass and weight, and how weirdly awesome Earth’s gravity really is.

5m 51s

Are You Afraid of Holes?

Honeycomb. Strawberries. Flower pods. Some people find these things incredibly scary. We call this extreme fear trypophobia. But why does it exist?

9m 5s

The Impossible Hugeness of Deep Time

Humans have a hard time with really big numbers, especially when it comes to DEEP TIME. The history of the Earth took a lot longer than you think, trust me. But I’m here to help you put it in perspective. With some string.

9m 44s

Is There Life on Earth?

If we lived light years from Earth, how would we know there’s life here? Let’s take a look at the search for extraterrestrial life on habitable exoplanets, and discover what biosignatures would show someone else that we’re here.

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