Electric eels zap fish and other underwater prey, but what would make them leap out of the water and shock an animal like a horse? Nineteenth-century naturalist and explorer Alexander von Humboldt first described eels emerging from the water to attack horses, and now Kenneth Catania of Vanderbilt University uses some unique props to reveal shocking insights about the behavior.

CREDITS
Produced by Emily Driscoll
Filmed by Jeff Nash
Narration by Luke Groskin
Alexander von Humboldt voiced by Eric Kuhl
Music by Audio Network
Additional Video by Kenneth Catania Lab
Photos and Images by Emil Du Bois-Reymond, Otto Roth, Robert Schomburgk, Shutterstock, Alexander von Humboldt, Friederich Georg Weitsch

Thanks to
Kenneth Catania, Luke Groskin, Eric Kuhl, David Salisbury

Polaroid's 20x24 cameras, built in the late 70s and named for the dimensions of their snapshots--20 by 24 inches, are the largest living Polaroid cameras in the world. (There was once an even bigger one with 40x80 snapshots but the film has run out.) Five of these 20x24 cameras still exist, and one resides in New York City's 20x24 Studio. The Studio's director, artist John Reuter, demonstrated the 235-pound camera, and Christopher Bonanos, author of Instant: The Story of Polaroid, explained how this camera fits into Polaroid's history.

http://www.sciencefriday.com
t's not just generations of children who have pondered how many licks it takes to reach the center of a lollipop. Mathematicians studying fluid dynamics at NYU's Applied Mathematics Lab designed experiments to watch how lollipops dissolve, and in doing so answered this epic childhood question. Help test their results by taking the Science Friday Lollipop Challenge!
Produced by Emily V. Driscoll
Filmed and Narrated by Luke Groskin
Music by Audio Network
Additional Footage by
Jinzi "Mac" Huang, Nicholas Moore, & Leif Ristroph
Tootsie Roll Industries, Inc.
Photographs by
NYU Applied Mathematics Lab
Shutterstock
Featuring
Leif Ristroph
Leo Groskin
Saydi Landon
Melanie Soumbasakis
Thanks to
Barry Bowen
James Devitt
Ellen Gordon
Luke Groskin
Jinzi "Mac" Huang
Elizabeth Delucia Landon
Leif Ristroph
Tootsie Roll Industries, Inc.
Megan Davies Wykes

A robot that's meant to swim with the fishes. Mechanical engineer Maurizio Porfiri, of the Polytechnic Institute of New York University, designs robot fish. A few years ago, he found that real fish would mill about his aquatic robot, and now he's trying to understand why. His research suggests that it has less to do with how the robot looks, than how it makes fish feel.

Sandor Ellix Katz, self-proclaimed "fermentation revivalist" and author of "The Art of Fermentation" (Chelsea Green Publishing, 2012) discusses the two "cultures."

Related:
Michael Pollan on Science Friday (May 3, 2013) http://www.sciencefriday.com/s....egment/05/03/2013/mi

This device smells. Using DNA, scientists built an electronic sniffing machine.

When two pendulums are attached to each other, their motion is impossible to predict. This swinging pendulum demonstration is brought to you by Science Friday

Spring is here and the birds are migrating. We went birding with Glenn Phillips, executive director of New York City Audubon, to learn some birding basics in preparation for the spring bird migration. Turf wars, death, joy--all in a day of birding.

How much should you get paid for your job? Well, that depends on a lot of factors. Your skill set, the demand for the skills you have, and what other people are getting paid around you all factor in. In a lot of ways, labor markets work on supply and demand, just like many of the markets we talk about in Crash Course Econ. But, again, there aren't a lot of pure, true markets in the world. There are all kinds of oddities and regulations that change the way labor markets work. One common (and kind of controversial one) is the minimum wage. The minimum wage has potential upsides and downsides, and we'll take a look at the various arguments for an against it.

Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

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In which John Green teaches you the history of Islam, including the revelation of the Qu'ran to Muhammad, the five pillars of Islam, how the Islamic empire got its start, the Rightly Guided Caliphs, and more. Learn about hadiths, Abu Bakr, and whether the Umma has anything to do with Uma Thurman (spoiler alert: it doesn't). Also, learn a little about the split between Sunni and Shia Muslims, and how to tell if this year's Ramadan is going to be difficult for your Muslim friends. Let's try to keep the flame wars out of this reasoned discussion.


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How do different societies establish a social hierarchy? Today we’re starting our unit on social stratification, starting with four basic principles of a sociological understanding of stratification. We’ll explain open and closed systems of stratification and explore examples of different kinds of stratification systems, including caste systems and class systems.

Crash Course is made with Adobe Creative Cloud. Get a free trial here: https://www.adobe.com/creativecloud.html

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Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

Thanks to the following Patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:

Mark, Les Aker, Bob Kunz, Mark Austin, William McGraw, Jeffrey Thompson, Ruth Perez, Jason A Saslow, D.A. Noe, Shawn Arnold, Eric Prestemon, Malcolm Callis, Advait Shinde, Rachel Bright, Khaled El Shalakany, Ian Dundore, Tim Curwick, Ken Penttinen, Dominic Dos Santos, Indika Siriwardena, Caleb Weeks, Kathrin Janßen, Nathan Taylor, Andrei Krishkevich, Brian Thomas Gossett, Chris Peters, Kathy & Tim Philip, Mayumi Maeda, Eric Kitchen, SR Foxley, Tom Trval, Cami Wilson, Moritz Schmidt, Jessica Wode, Daniel Baulig, Jirat
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Today we’re going to talk about numeracy - that is understanding numbers. From really really big numbers to really small numbers, it's difficult to comprehend information at this scale, but these are often the types of numbers we see most in statistics. So understanding how these numbers work, how to best visualize them, and how they affect our world can help us become better decision makers - from deciding if we should really worry about Ebola to helping improve fighter jets during World War II!

Episode Notes:

Tim Urban’s wonderful post about visualizing large numbers:
https://waitbutwhy.com/2014/11..../from-1-to-1000000.h

Some of our reading that inspired this episode:
How Not to Be Wrong: The Power of Mathematical Thinking by Jordan Ellenberg
Innumeracy: Mathematical Illiteracy and its Consequences by John Allen Paulos

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Thanks to the following Patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:

Mark Brouwer, Nickie Miskell Jr., Jessica Wode, Eric Prestemon, Kathrin Benoit, Tom Trval, Jason Saslow, Nathan Taylor, Divonne Holmes à Court, Brian Thomas Gossett, Khaled El Shalakany, Indika Siriwardena, Robert Kunz, SR Foxley, Sam Ferguson, Yasenia Cruz, Daniel Baulig, Eric Koslow, Caleb Weeks, Tim Curwick, Evren Türkmenoğlu, Alexander Tamas, Justin Zingsheim, D.A. Noe, Shawn Arnold, mark austin, Ruth Perez, Malcolm Callis, Ken Penttinen, Advait Shinde, Cody Carpenter, Annamaria Herrera, William McGraw, Bader AlGhamdi, Vaso, Melissa Briski, Joey Quek, Andrei Krishkevich, Rachel Bright, Alex S, Mayumi Maeda, Kathy & Tim Philip, Montather, Jirat, Eric Kitchen, Moritz Schmidt, Ian Dundore, Chris Peters, Sandra Aft, Steve Marshall

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Media isn’t just movies and newspapers and TV shows, it’s also a part of society that involves a lot of money. And all that money has implications for the media that gets created. Media is created by people -- a range of people, making a range of decisions, and earning a range of different paychecks to do it. Those decisions matter and understanding how money affects those decisions is an essential component of media literacy.

***

Resources:

“What is Representation?” BBC Bitesize https://www.bbc.com/education/....guides/z9fx39q/revis

“The Whites of Their Eyes: Racist Ideologies and the Media” by Stuart Hall. Gender, Race, and Class in Media: A Text Reader. https://blog.richmond.edu/watc....hingthewire/files/20

“The Culture Industry: Enlightenment as Mass Deception” by Theodor Adorno https://web.stanford.edu/dept/....DLCL/files/pdf/adorn

“If It’s Hard to Read, It’s Hard to Do: Processing Fluency Affects Effort Prediction and Motivation” Psychological Science https://dornsife.usc.edu/asset....s/sites/780/docs/08_

“A Recipe for Motivation: Easy to Read, Easy to Do” Scientific American https://www.scientificamerican.....com/article/a-recip

***

Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

Thanks to the following Patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:

Mark Brouwer, Justin Zingsheim, Nickie Miskell Jr., Jessica Wode, Eric Prestemon, Kathrin Benoit, Tom Trval, Jason Saslow, Nathan Taylor, Divonne Holmes à Court, Brian Thomas Gossett, Khaled El Shalakany, Indika Siriwardena, Robert Kunz, SR Foxley, Sam Ferguson, Yasenia Cruz, Daniel Baulig, Eric Koslow, Caleb Weeks, Tim Curwick, Evren Türkmenoğlu, Alexander Tamas, D.A. Noe, Shawn Arnold, mark austin, Ruth Perez, Malcolm Callis, Ken Penttinen, Advait Shinde, Cody Carpenter, Annamaria Herrera, William McGraw, Bader AlGhamdi, Vaso, Melissa Briski, Joey Quek, Andrei Krishkevich, Rachel Bright, Alex S, Mayumi Maeda, Kathy & Tim Philip, Montather, Jirat, Eric Kitchen, Moritz Schmidt, Ian Dundore, Chris Peters,, Sandra Aft, Steve Marshall
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Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use

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Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use

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Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use

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Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use

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Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use

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Copyright Disclaimer Under Section 107 of the Copyright Act 1976, allowance is made for "fair use" for purposes such as criticism, comment, news reporting, teaching, scholarship, and research. Fair use is a use permitted by copyright statute that might otherwise be infringing. Non-profit, educational or personal use tips the balance in favor of fair use