Skip to main content

Up Next

How the Meter Became The Meter

How the Meter Became The Meter

Season 5 Episode 6
6:02
What is Luck?

What is Luck?

Season 5 Episode 8
5:10
How Much Plastic is in the Ocean?

How Much Plastic is in the Ocean?

Season 5 Episode 10
4:43
Why I ❤ PBS

Why I ❤ PBS

Season 5 Episode 11
2:32
Where Did Humans Come From?

Where Did Humans Come From?

Season 5 Episode 13
6:18
Why Are We The Only Humans Left?

Why Are We The Only Humans Left?

Season 5 Episode 14
6:09
Why Does Hair Grow The Way It Does?

Why Does Hair Grow The Way It Does?

Season 5 Episode 15
4:18
Are We All Related?

Are We All Related?

Season 5 Episode 16
6:06
Back to Show
It's Okay to Be Smart

How the Toilet Changed History

Season 5 Episode 5

It may sometimes seem like things are getting worse, but there’s lots of reasons to be optimistic about the future. More people have access to toilets and sanitation than ever before. Thanks to public health improvements like this, since 1990, 122 million children’s lives have been saved. Diseases like polio are nearing eradication. Women have more access to health care and education than ever bef

Support Provided By
Season
Mars Used to Be Blue... Then Something Happened
11:08
Why is the Martian sky red by day… but blue at sunset?
Be Smart about Autism
36:47
Is autism really on the rise—or are we just recognizing it more?
Why Seedless Fruit Is a Disaster Waiting To Happen
14:51
Seedless fruits are delicious, convenient… and completely unnatural.
The Randomness Crisis Threatening the Internet
21:13
What does randomness really mean? And why your digital life depend on it?
Blood Types Are Weirder Than You Think
16:20
Why do we have different blood types? And why do we have blood at all?
How Feathered Dinosaurs Accidentally Invented Flight
16:18
How did dinosaurs become birds—and what good is half a wing?
What Could We See with a Planet-Sized Telescope?
16:00
Just how big would a telescope need to be to actually see an alien world in detail?
The Argument for De-Extinction: Explained
26:19
Dire wolves are back—sort of.
Will Earth Run Out of Oxygen
16:53
The key enzyme behind photosynthesis isn’t actually all that great at its job.
What’s Inside the Oldest Rocks in the World?
16:40
The oldest rocks on Earth are more than just ancient—they’re time machines!
Why Your Grandma Is an Evolutionary Mystery
17:11
This is one of the weirdest mysteries of human evolution: Why do we have grandmas?
What Synesthesia Feels Like
12:28
Why do some people taste music or hear colors? Let’s talk about synesthesia.
Active loading indicator