Stuff You Should Know

Whatever happened to acid rain?

14 Jun 2012

Contributed by Lukas

Along with the hole in the ozone layer, acid rain was one of the first international environmental threats. It's fallen to the wayside in the face of ...

Should we have a fat tax?

12 Jun 2012

Contributed by Lukas

The concept of fighting unhealthy behavior like overeating by taxing unhealthy food has been around since 1994. But as the debate over a fat tax rages...

Fractals: Whoa

07 Jun 2012

Contributed by Lukas

In the 1980s, IBM mathematician Benoit Mandelbrot gazed for the first time upon his famous fractal. What resulted was a revolution in math and geometr...

How Moss Works

05 Jun 2012

Contributed by Lukas

Think you have moss figured out? You probably don't. Join Josh and Chuck as they explore some of the surprising aspects of these most ancient and impo...

Can it rain frogs?

31 May 2012

Contributed by Lukas

If you've seen the movie Magnolia, you've seen what it looks like to rain frogs. While there are reports of frogs, fish and even squid raining down th...

Do video games produce real-life violence?

29 May 2012

Contributed by Lukas

The disturbing trend of school shootings around the world has dragged violence in video games into the hot seat. But are violent video games actually ...

Are we obsessed with goals?

24 May 2012

Contributed by Lukas

We've all been brought up to keep our eyes on the prize and our pedal to the medal when we go for that brass ring, but does the Western interest in go...

How Labor Unions Work

22 May 2012

Contributed by Lukas

Yes, it's true: Unions have a shady mob-related past and were originally championed by anarchists. Born from medieval trade guilds, these organization...

What is the future of Earth?

17 May 2012

Contributed by Lukas

What will the Earth be like in 5,000 or 50,000 years? In this far-sighted episode, Josh and Chuck explore how Earth may change over time. Listen in to...

Interpol: World Police

15 May 2012

Contributed by Lukas

Interpol is an international police agency that helps other law-enforcement agencies track criminals who operate across national borders -- but how do...

What is a shotgun house?

10 May 2012

Contributed by Lukas

Shotgun houses are iconic pieces of American architecture: they're long, narrow, and filled with artistic flourishes. But where did they come from? In...

Did the Dutch trade Manhattan for nutmeg?

08 May 2012

Contributed by Lukas

Today nutmeg is commonplace, but this wasn't always the case. In the 17th century, the Dutch and the British fought a trade war over nutmeg. Join Chuc...

How Bullfighting Works

03 May 2012

Contributed by Lukas

When the Visigoths ruled Spain, they introduced the idea of battling bulls at festivals. Today matadors get paid $100,000 and perform in front of 50,0...

How did language evolve?

01 May 2012

Contributed by Lukas

" Sure animals talk in their own way, with chirps and grunts and the like, but only humans can form words. It is this, some evolutionary psychologists...

How Medical Marijuana Works

26 Apr 2012

Contributed by Lukas

Some quarters of the medical establishment endorse it, others abhor it. The DEA is cracking down on it, but the Veterans' Administration supports it a...

How Air Traffic Control Works

24 Apr 2012

Contributed by Lukas

You know how when you fly in an airline you usually don't die? You can thank the battalion of air traffic control professionals who studiously track e...

Social Security Numbers: Less Boring Than You'd Think

19 Apr 2012

Contributed by Lukas

Do you know that up until July 2011 an ambitious hacker with a good software program could deduce your social security number based on your date and p...

How Whaling Works

17 Apr 2012

Contributed by Lukas

Despite its embattled status as brutal and illegal, commercial whaling is a tradition that dates back 1,000 years and served as the economic engine of...

Body Odor: You Stink

11 Apr 2012

Contributed by Lukas

Chuck and Josh end up making reduxes of past episodes on things like sweating and deodorant in this all-new episode on the science beneath what makes ...

Was Atlantis a real place?

10 Apr 2012

Contributed by Lukas

While the search for Atlantis has been pushed to the fringes since the 19th century, archaeologists have quietly pursued cities that may have inspired...

How Diamonds Work

03 Apr 2012

Contributed by Lukas

There's no denying that diamonds are pretty -- but where do they come from, and why are they so expensive? Join Chuck and Josh as they explore everyth...

How Music Sampling Works

29 Mar 2012

Contributed by Lukas

Today music sampling is a common practice, especially in electronic or hip-hop music. But how does it work? After all, other artists made the original...

10 Big Cases of Revenge

27 Mar 2012

Contributed by Lukas

Who doesn't love a good story about comeuppance? Whether served cold or piping hot, revenge is an ancient idea -- and history is filled with acts of v...

How Tipping Works

22 Mar 2012

Contributed by Lukas

Tipping is commonly expected in some places, such as U.S. restaurants. Yet this practice varies across cultures. Join trivia gurus (and former waiters...

How Comic Books: Live from SXSW

20 Mar 2012

Contributed by Lukas

Although you might not be a fan of comic books, there's no denying that they have a fascinating place in American history. And -- as if that wasn't in...

How the Donner Party Worked

15 Mar 2012

Contributed by Lukas

Did they or didn't they? There is plenty of written evidence that the ill-fated Donner Party resorted to cannibalism - except there are no bones. Lear...

Should chimps be used for medical testing?

13 Mar 2012

Contributed by Lukas

If you've got half a heart it's an easy question to answer. But if you're happy living without polio and hepatitis B you may want to question further....

How Noah's Ark Worked

08 Mar 2012

Contributed by Lukas

Stories of a great flood and a man who managed to stay afloat while the world drowned abound in ancient traditions. Join Josh and Chuck as they explor...

Duels: A guide to throwing down the gauntlet

06 Mar 2012

Contributed by Lukas

Pretty much everything you know about duels is true - it's a challenge to violence to defend honor. But did you know the U.S. Navy used to publish det...

How SETI Works

01 Mar 2012

Contributed by Lukas

SETI stands for 'search for extraterrestrial intelligence,' and the term is used to describe both the SETI institute and the search for alien life in ...

How Crying Works

28 Feb 2012

Contributed by Lukas

You probably did it around 70 times last year, yet you probably don't understand the psychological and physiological processes at work when you cried....

Fasting: deadly or what?

23 Feb 2012

Contributed by Lukas

Avoiding food for religious or health reasons has been around for millennia. But while God may appreciate the sacrifice, how does it affect the body? ...

How Autopsies Work

16 Feb 2012

Contributed by Lukas

In the 400th episode of Stuff You Should Know, Josh and Chuck take a trip through the morgue and look over the shoulders of the often controversial co...

How Zero Works

14 Feb 2012

Contributed by Lukas

Few numbers have as storied a past as zero. Even fewer have had as great an impact on our ability to understand our universe. Yet zero is a relatively...

How Coral Reefs Work

09 Feb 2012

Contributed by Lukas

Coral reefs are the largest organic structures on Earth, yet they're created through a symbiotic relationship between creatures about 3 millimeters lo...

Pickpockets: Artists or Crooks?

07 Feb 2012

Contributed by Lukas

There aren't many criminal pursuits that are as storied as pickpocketing, and some people fondly reminisce over its heyday. Learn why some consider pi...

How Floods Work

26 Jan 2012

Contributed by Lukas

Floods happen when more water is introduced to an area than can be quickly removed. That's about it, but there's more to floods, what causes them and ...

How Human Trafficking Works

24 Jan 2012

Contributed by Lukas

Despite worldwide prohibitions, slavery still exists. Slaves are forced or coerced into prostitution or made to work in deplorable factory conditions....

How Mexican Wrestling Works

19 Jan 2012

Contributed by Lukas

Perhaps it's the colorful masks or the high-flying, rapid-fire acrobatic moves. Whatever it is, there's something uniquely and particularly entrancing...

Are contrails actually chemtrails?

17 Jan 2012

Contributed by Lukas

You know those trails that jets leave in the sky? While science has explained why they happen, plenty of conspiracy theorists believe there's more to ...

What's the deal with the Bermuda Triangle?

12 Jan 2012

Contributed by Lukas

There's roughly 500,000 squares miles encompassed in a triangle with points in Miami, Bermuda and San Juan. There shouldn't be anything different abou...

Can you vacation in Antarctica?

10 Jan 2012

Contributed by Lukas

The answer is yes, but there's a lot more to traveling to the southernmost continent. Learn why emperor penguins don't make eye contact with humans, w...

Was there a curse on King Tut's tomb?

05 Jan 2012

Contributed by Lukas

When Howard Carter opened Tutankhamen's tomb, some believe he unleashed a curse on everyone associated with his expedition. But there's no such thing ...

How Yo-Yos Work

03 Jan 2012

Contributed by Lukas

You may have played with a yo-yo before -- perhaps you've even walked the dog -- but do you know about the physics behind what makes a yo-yo sleep and...

Coffee: The World's Drug of Choice

29 Dec 2011

Contributed by Lukas

There's a 98 percent chance you're drinking coffee right now. Maybe not, sure, but coffee is ubiquitous - about 80 percent of Americans consume coffee...

What happens in the brain during an orgasm?

27 Dec 2011

Contributed by Lukas

Chuck and Josh test the limits of their decorum as they explore the physiology of an orgasm. Learn all about this inexplicably taboo subject (includin...

Josh and Chuck's Christmas Extravaganza

22 Dec 2011

Contributed by Lukas

Have you ever wondered why the poinsettia is the official plant of Christmas or why we hang stockings by the chimney with care? Join Chuck and Josh fo...

How Pepper Spray Works

20 Dec 2011

Contributed by Lukas

Lt. John Pike of the Davis, Calif., police department brought the wrath of the Internet on himself when he casually doused peaceful protestors with pe...

How Earthworms Work

15 Dec 2011

Contributed by Lukas

Earthworms come in a wide range of sizes: The average U.S. earthworm is 6 to 11 inches long, and the giant worms of Australia and South America can gr...

How the Digestive System Works

08 Dec 2011

Contributed by Lukas

The digestive system uses mechanical and chemical processes to absorb and transport all the nutrients your body needs to survive -- but how does it wo...

How Daylight Saving Time Works

06 Dec 2011

Contributed by Lukas

Benjamin Franklin first came up with daylight saving time in 1748, and people still practice it today. But how does it work? What are the pros and con...

What made the donkey and the elephant political?

01 Dec 2011

Contributed by Lukas

Sure we take it for granted the elephant represents the Republican party and the donkey Democrats, but have you ever wondered why? Josh and Chuck expl...

Cash Debit or Credit: Which is best?

29 Nov 2011

Contributed by Lukas

Chuck and Josh take a stab at answering the age old question of whether cash or plastic is the best choice for paying your way through life. Join them...

How Thoroughbred Horses Work

24 Nov 2011

Contributed by Lukas

It's been just 300 years since the Thoroughbred breed has been around, but it has produced some of the most storied animals humans have ever loved. Ch...

Crossbows: They Look Cool

22 Nov 2011

Contributed by Lukas

Sure, they look cool. It's as if someone put a bow and a rifle together, but in fact crossbows predate firearms by a few thousand years. Learn all abo...

How Air Force One Works

17 Nov 2011

Contributed by Lukas

As you might imagine, the President of the United States doesn't fly coach. But what exactly does he use when traveling from point A to point B, and h...

How Alcatraz Works

15 Nov 2011

Contributed by Lukas

Sure, you've heard stories about Alcatraz. From high-profile escape attempts to tales of notorious inmates, the Rock is unique in American history. Bu...

How Presidential Debates Work

10 Nov 2011

Contributed by Lukas

The first televised Presidential debate had some odd results: The radio audience tended to believe Nixon won, while television viewers supported Kenne...

How Gene Patents Work

08 Nov 2011

Contributed by Lukas

Should a company be able to own the rights to something found inside your own body? In this episode, Chuck and Josh delve into the complicated, contro...

What Saved the American Bison

03 Nov 2011

Contributed by Lukas

The pre-colonial range of the American bison stretched from Canada to Mexico. From 1820 to 1880, the population dwindled from 30 million to just over ...

How the Autobahn Works

01 Nov 2011

Contributed by Lukas

The autobahn has an international reputation, and people around the world love the notion of driving on a road with no speed limits -- but how true is...

Berenice

27 Oct 2011

Contributed by Lukas

It's Halloween again, and this year Chuck and Josh are ringing in the holiday with a special reading of the short story "Berenice," by Edgar Allan Poe...

How Anti-matter Spacecraft Will Work

25 Oct 2011

Contributed by Lukas

There may be a Bizarro World in our universe. Every particle has a mirror image with a reverse electrical charge, and when these opposites meet an ene...

Do you lose the right to privacy when you die?

20 Oct 2011

Contributed by Lukas

If you live in a place where privacy is protected, the legal system keeps prying eyes from your personal information. But does that privacy extend bey...

The Nile IS Just a River in Egypt

18 Oct 2011

Contributed by Lukas

The Nile River has been flowing south to north for about 30 million years, and the human race's cradle may have been along the Blue Nile stemming from...

The Wind Cries Typhoid Mary

13 Oct 2011

Contributed by Lukas

In the 19th century, typhoid was considered a disease of the lower classes. When an outbreak occurred in wealthy Oyster Bay, New York, a mystery was a...

A Podcast on Zoot Suits? Yes

11 Oct 2011

Contributed by Lukas

Few riots can be attributed to passing fashions, but zoot suits are top among them. After originating among the Harlem Renaissance crowd, the zoot sui...

How the Peace Corps Works

06 Oct 2011

Contributed by Lukas

Since its inception, the Peace Corps has sent 200,000 members to 193 countries to deliver aid and good will through know-how rather than direct fundin...

How Silly Putty Works

04 Oct 2011

Contributed by Lukas

When the Japanese invaded Southeast Asia in World War II, they cut off America's rubber supply. Luckily, American can-do created a synthetic rubber an...

How U.S. Marshals Work

29 Sep 2011

Contributed by Lukas

Thought Chuck and Josh had already covered every law enforcement agency? Think again. The Marshals Service is the oldest law enforcement branch in the...

How Sword Swallowing Works

27 Sep 2011

Contributed by Lukas

Houdini suggested that sword swallowing was merely a trick. But there's no sleight of hand or throat to this ancient practice. Practitioners really do...

How Family Crests Work

22 Sep 2011

Contributed by Lukas

After 800 years of creating coats and crests, some meaning has been lost to history, but much has been retained and is still in use. Find out what a m...

How Acne Works

20 Sep 2011

Contributed by Lukas

Over the course of our lives, 80 percent of us will experience acne. Ultimately, acne comes down to one thing, a blockage in the sebaceous gland. Lear...

How the Moon Works

15 Sep 2011

Contributed by Lukas

Did you know that science still doesn't know the exact origin of the moon? Do you know how the moon creates high and low tides? Do you know the differ...

How Casinos Work

13 Sep 2011

Contributed by Lukas

Gambling predates the written word; dice made of bones have been discovered at prehistoric sites. Today, the concept of amassing a fortune in moments ...

How the World Trade Center Memorial Works

08 Sep 2011

Contributed by Lukas

The World Trade Center was once a global symbol of progress. Since the attacks of Sept. 11, the area has undergone a massive rebuilding process. Chuck...

10 Scientists Who Were Their Own Guinea Pigs

06 Sep 2011

Contributed by Lukas

Over the centuries, some scientists have concluded that the best test subject is looking at them in the mirror. Join Josh and Chuck as they explore 10...

How Lie Detectors Work

01 Sep 2011

Contributed by Lukas

Instead of actually detecting lies, polygraph machines sense physiological variations, ostensibly brought on by guilt. The results are subject to inte...

Cryonics: Hi, Frozen Body!

30 Aug 2011

Contributed by Lukas

In 1964 The Prospect of Immortality laid out a plan for placing humans in suspended animation. The first person was placed in cryonic suspension three...

How Schizophrenia Works

23 Aug 2011

Contributed by Lukas

Up to 24 million people worldwide have schizophrenia. Despite the vast amounts of research, the disorder remains mysterious. In this episode, Josh and...

How to Land on a Government Watch List

18 Aug 2011

Contributed by Lukas

The U.S. Government's Consolidated Terrorist Watch List keeps track of people who are known or suspected terrorists. But what how do people end up on ...

How Murphy's Law Works, the Redux

16 Aug 2011

Contributed by Lukas

Years back, Josh recorded this show without Chuck, and the old version's omitted facts bugged him. In this new version, the pair delve into the people...

Laughter: What's so funny about that?

11 Aug 2011

Contributed by Lukas

The response to humor starts with electrical activity, potentially translating to physical responses that make up laughter. Science still can't pin do...

What's the future of the internet?

09 Aug 2011

Contributed by Lukas

It's tough to predict the future. Instead, the future looks a lot like it does now: Faster data transfer rates, more social networking, ubiquitous mob...

Ethnobotany: How to Get Drugs from Plants

04 Aug 2011

Contributed by Lukas

In 1820, most of the drugs listed in the American Pharmacopoeia were plant-based; by 1960, it was a mere 5 percent. Yet in the late 20th century this ...

Can you sweat colors?

02 Aug 2011

Contributed by Lukas

A condition known as chromhidrosis can be jarring: The sufferer excretes colored sweat from the eccrine or the apocrine sweat glands. Join Josh and Ch...

How SPAM Works

28 Jul 2011

Contributed by Lukas

SPAM is a canned meat product made from pork shoulder and ham. First introduced in 1937, this iconic food has spread to stores across the world. But w...

How Wildfires Work

26 Jul 2011

Contributed by Lukas

Wildfires consume an annual average of 5 million acres in the US. But what causes wildfires? How do they become so powerful? More importantly, how do ...

How Karma Works

21 Jul 2011

Contributed by Lukas

While it's kind of perverted in the West, the concept of karma is a central tenet of several Eastern religions. Karma isn't just good or bad -- it's a...

Does smiling make you happy?

19 Jul 2011

Contributed by Lukas

You smile because you're happy, yet happiness research suggests the opposite can also hold true. Smiling may actually improve your mood. Open interpre...

Stuff You Should Know July 4th Extravaganza, Part 2: Baseball and Apple Pie

14 Jul 2011

Contributed by Lukas

What makes America unique? In the second segment of this special two-part episode, Josh and Chuck join up with guests from The Daily Show and The Onio...

Stuff You Should Know July 4th Extravaganza, Part 1: Mom

12 Jul 2011

Contributed by Lukas

What makes America unique? In the first segment of this special two-part episode, Josh and Chuck join up with guests from The Daily Show and The Onion...

How Human Cannonballs Work

07 Jul 2011

Contributed by Lukas

There's no question that human cannonballs are daredevils. They pack themselves into the confines of huge cannons, which shoot them into the air. But ...

How Hate Works

05 Jul 2011

Contributed by Lukas

Hate is generally defined as an extreme hostility to something or someone, usually stemming from fear, anger or a sense of injury. But how does it wor...

Who was America's first murderer?

30 Jun 2011

Contributed by Lukas

John Billington didn't just sign the Mayflower Compact -- he was also the colony's first criminal, and had the dubious honor of being the first Europe...

How Asteroid Mining Could Work

28 Jun 2011

Contributed by Lukas

There may be trillions of dollars' worth of resources in asteroids, and some scientists believe we could mine nearby asteroids. Join Josh and Chuck as...

How Suicide Bombers Work

21 Jun 2011

Contributed by Lukas

It 1981 the first modern suicide bomber blew himself up. But this was by no means the first suicide bombing. Israeli psychologists evaluated the motiv...

How Curiosity Works

16 Jun 2011

Contributed by Lukas

Alternately hailed a crucial part of the human condition or accused of killing cats, curiosity remains a subject of debate among researchers. Where do...

How Military Snipers Work

14 Jun 2011

Contributed by Lukas

Military snipers always work in pairs, and they're called force multipliers because of the profound effect a two-man team can have on a rival military...

Was Malthus right about carrying capacity?

09 Jun 2011

Contributed by Lukas

Thomas Malthus concluded that humanity is bound to outgrow Earth's carrying capacity. The prediction was based on humanity's exponential growth and th...