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Continuing our look at Nuclear Chemistry, Hank takes this episode to talk about Fusion and Fission. What they mean, how they work, their positives, negatives, and dangers. Plus, E=mc2, Mass Defect, and Applications of Fission and Fusion in the real world!

--
Table of Contents

E=mc2
Mass Defect
Fission vs. Fusion
Applications in the Real World

--
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Hank gives us a tour of the most important table ever, including the life story of the obsessive man who championed it, Dmitri Mendeleev. The periodic table of elements is a concise, information-dense catalog of all of the different sorts of atoms in the universe, and it has a wealth of information to tell us if we can learn to read it.

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Table of Contents
Dmitri Mendeleev - 0:45
Mendeleev's Organization of the Periodic Table - 2:31
Relationships in the Periodic Table - 5:03
Why Mendeleev Stood Out from his Colleagues - 7:09
How the Periodic Table Could be Improved - 8:28

More info. about the cylindrical periodic table of elements: http://www.av8n.com/physics/periodic-table.htm Support CrashCourse on Subbable: http://subbable.com/crashcourse

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How did we get here? Well, in terms of Atomic Chemistry, Hank takes us on a tour of the folks that were part of the long chain of other folks who helped us get to these deeper understandings of the world. From Leucippus to Heisenberg to you - yes, YOU - the story of Atomic Chemistry is all wibbly-wobbly... and amazing.

--
Table of Contents

Leucippus, Democritus & Atomic Theory 0:09
Discharge Tubes 1:52
Ernest Rutherford & The Nucleus 4:22
Chemistry = Math 7:22
Niels Bohr Model 5:32
Heisenburg & Quantum Theory 6:35
--
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Dihydrogen monoxide (better know as water) is the key to nearly everything. It falls from the sky, makes up 60% of our bodies, and just about every chemical process related to life takes place with it or in it. Without it, none of the chemical reactions that keep us alive would happen - none of the reactions that sustain any life form on earth would happen - and the majority of inorganic chemical reactions that shape the surface of the earth would not happen either. Every one of us uses water for all kinds of chemistry every day - our body chemistry, our food chemistry and our laundry chemistry all take place in water.
In today's Crash Course Chemistry, we use Hank's actual dirty laundry (ew) to learn about some of the properties of water that make it so special - it's polarity and dielectric property; how electrolytes can be used to classify solutions; and we discover how to calculate a solution's molarity as well as how to dilute a solution using the dilution equation.

Table of Contents
Polarity 02:40
Dielectric Property 04:13
Electrolytes 04:29
Molarity 08:46
Dilution 10:56

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Now that we’ve finished our tour of the planets, we’re headed back to the asteroid belt. Asteroids are chunks of rock, metal, or both that were once part of smallish planets but were destroyed after collisions. Most orbit the Sun between Mars and Jupiter, but some get near the Earth. The biggest, Ceres is far smaller than the Moon but still big enough to be round and have undergone differentiation.

CORRECTION: In the episode we say that 2010 TK7 is 800 km away. However, 2010 TK7 stays on average 150 million kilometers from Earth, but that can vary wildly.
Sorry about that!

--

Table of Contents
Asteroids Are Chunks of Rock, Metal, or Both 1:45
Most Orbit the Sun Between Mars and Jupiter 7:16
Ceres is Far Smaller Than the Moon, But Large Enough to be Round 3:43

--

PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Follow Phil on Twitter: https://twitter.com/badastronomer

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--

PHOTOS/VIDEOS
Timelapse of Asteroid 2004 FH's flyby http://en.wikipedia.org/wiki/F....ile:Asteroid_2004_FH [credit: NASA/JPL Public Domain]
Asteroid Discovery Video https://www.youtube.com/watch?v=2k2vkLEE4ko [credit: Scott Manley - scottmanley1972@gmail.com]
Inner Solar System http://en.wikipedia.org/wiki/F....ile:InnerSolarSystem [credit: Wikimedia Commons]
Kirkwood gaps http://commons.wikimedia.org/w....iki/File:Kirkwood-ga [credit: Wikimedia Commons]
Ceres, Earth & Moon size comparison http://en.wikipedia.org/wiki/F....ile:Ceres,_Earth_%26 [credit: NASA]
Dawn Glimpses Ceres’ North Pole http://www.jpl.nasa.gov/news/n....ews.php?release=2015 [credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA]
Ceres cutaway http://commons.wikimedia.org/w....iki/File:Ceres_Cutaw [credit: NASA, ESA, and A. Feild (STScI)]
Bright Spot on Ceres Has Dimmer Companion http://www.jpl.nasa.gov/spacei....mages/details.php?id [credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA]
Vesta http://en.wikipedia.org/wiki/4...._Vesta#/media/File:V [credit: NASA/JPL-Caltech/UCAL/MPS/DLR/IDA]
Lutetia http://en.wikipedia.org/wiki/2....1_Lutetia#/media/Fil [credit: ESA]
Gaspra http://commons.wikimedia.org/w....iki/File:Galileo_Gas [credit: NASA]
Steins http://neo.ssa.esa.int/image/image_gallery?uuid=db747cf5-9d21-405e-bcdb-e70fe475edc9&groupId=10157&t=1340734455649 [credit: ESA/Osiris]
Mathilde http://neo.jpl.nasa.gov/images/mathilde1.jpg [credit: NEAR Spacecraft Team, JHUAPL, NASA]
Ida http://en.wikipedia.org/wiki/2....43_Ida#/media/File:2 [credit: NASA/JPL]
Kleopatra http://apod.nasa.gov/apod/ap000510.html [credit: Stephen Ostro et al. (JPL), Arecibo Radio Telescope, NSF, NASA]
An artist's conception of two Pluto-sized dwarf planets in a collision around Vega. http://en.wikipedia.org/wiki/M....ethods_of_detecting_ [credit: NASA/JPL-Caltech/T. Pyle (SSC)]
Itokawa http://apod.nasa.gov/apod/ap140209.html [credit: ISAS, JAXA]
An artist's illustration showing two asteroid belts and a planet orbiting Epsilon Eridani http://en.wikipedia.org/wiki/E....psilon_Eridani#/medi [credit: NASA/JPL-Caltech]
Near-Earth Asteroids http://www.jpl.nasa.gov/images..../asteroid/20130204/a [credit: NASA/JPL-Caltech]
Lagrange Points Diagram http://en.wikipedia.org/wiki/T....rojan_(astronomy)#/m [credit: Wikimedia Commons]
TK7 http://en.wikipedia.org/wiki/2....010_TK7#/media/File: [credit: NASA/JPL-Caltech/UCLA]
165347 Philplait http://www.slate.com/content/d....am/slate/blogs/bad_a [credit: Larry Denneau/Pan-STARRS via Amy Mainzer]

In which Jacob Clifford and Adriene Hill teach you about Economic Systems and Macroeconomics. So, economics is basically about choices. We'll look at some of the broadest economic choices when we talk about the difference between planned economies and market economies. We'll get into communism, socialism, command economies, and capitalism. We'll look at how countries choose the kind of system they're going to use (spoiler alert: many end up with mixed economies). We'll also look into how individuals make economic choices.

Crash Course is now 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, Jan Schmid, Anna-Ester Volozh, Robert Kunz, Jason A Saslow, Christian Ludvigsen, Chris Peters, Brad Wardell, Beatrice Jin, Roger C. Rocha, Eric Knight, Jessica Simmons, Jeffrey Thompson, Elliot Beter, Today I Found Out, James Craver, Ian Dundore, Jessica Wode, SR Foxley, Sandra Aft, Jacob Ash, Steve Marshall

TO: Everyone
FROM: Martin

To gild refined gold is just silly.


TO: Dana
FROM: Cameron

Still holding out. We're going to make it!

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Hank bursts our ideal gas law bubble, er, balloon, and brings us back to reality, explaining how the constants in the gas law aren't all that constant; how the ideal gas law we've spent the past two weeks with has to be corrected for volume because atoms and molecules take up space and for pressure because they're attracted to each other; that Einstein was behind a lot more of what we know today than most people realize; and how a Dutch scientist named Johannes van der Waals figured out those correction factors in the late 19th century and earned a Nobel Prize for his efforts.

Table of Contents
Constants in the Gas Laws Aren't all that Constant 1:20
The Ideal Gas Law has to be Corrected for Volume and Pressure 3:26
Einstein was the Bomb 5:02
Van Der Waals Equation 9:38
Never Give Up! 10:08

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In this episode, Hank goes over Reversible Reactions, the water dissociation constant, what pH and pOH actually mean, Acids, Bases, and Neutral Substances as well as the not-so-terrifying Logarithms, strong acids, weak acids, and how to calculate pH and pOH. Oh, and litmus paper!

***** AND NOW, A SUBBABLE MESSAGE! *****
"Daisy, we love you more than you love John and Hank!
From Mum and Nemo."

--
Table of Contents
Reversible Reactions 3:40
Water Dissociation Constant 5:00
Acids, Bases, & Neutral Substances 6:38
Strong and Weak Acids 7:43
Logarithms 1:46
Calculating pH and pOH 8:45
Cool Mathematical Connections 9:54

--
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This week Craig Benzine takes a first look at the judicial branch. It's pretty easy to forget that the courts, and the laws that come out of them, affect our lives on a daily basis. But how exactly these decisions are made and where each law's jurisdiction starts and ends can get pretty complicated. So complicated in fact that you may want to smash something. But don't worry, Craig will clear the way.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Support is provided by Voqal: http://www.voqal.org

All Flickr.com images are licensed under Creative Commons by Attribution 2.0
http://creativecommons.org/lic....enses/by/2.0/legalco

--

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In this episode, Hank welcomes you to the new age, to the new age, welcome to the new age. Here he'll talk about transmutation among elements, isotopes, calculating half-life, radioactive decay, and spontaneous fission.

SUBBABLE MESSAGE:

"To Crash Course
From Shawn, Mike, Sophia, and Jake"

"Thank you for using humor while educating and inspiring."

--
Table of Contents

Radioactivity
Transmutation Among Elements and Isotopes
Calculating Half-Life
Radioactive Decay
Spontaneous Fission
--
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Hank gets real with us in a discussion of evolution - it's a thing, not a debate. Gene distribution changes over time, across successive generations, to give rise to diversity at every level of biological organization.

Crash Course Biology is now available on DVD! http://dft.ba/-8css

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Table of Contents
1) The Theory of Evolution 1:49
2) Fossils 2:42
3) Homologous Structures 4:36
4) Biogeography 7:02
5) Direct Observation 8:52

References for this episode can be found in the Google document here: http://dft.ba/-2Oyu

evolution, theory, biology, science, crashcourse, genetics, gene, facts, fossil, fossil record, dinosaur, extinct, extinction, organism, dorudon, rodhocetus, vestigial, structure, similarity, homologous structure, related, relationship, morganucodon, fore limb, hind limb, vertebrate, molecule, DNA, RNA, chimpanzee, fruit fly, biogeography, marsupial, finches, direct observation, drug resistance, resistance, selective pressure, italian wall lizard Support CrashCourse on Subbable: http://subbable.com/crashcourse

** Re-uploaded because there was an error with a map **

You might have recognized the names of some of the Greek natural philosophers. They were individuals with quirky theories, and we have records about them. But they weren’t the only people making knowledge back in the day. Today, Hank takes us to India to talk Vedas, Maurya Empires, and some really good doctoring.

***

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Crash Course World History is now available on DVD! Visit http://dft.ba/-CCWHDVD to buy a set for your home or classroom.

In which John Green teaches you about what is often called the Reagan Era. Mainly, it covers the eight years during which a former actor who had also been governor of the state of California was president of the United States. John will teach you about Reagan's election victory over the hapless Jimmy Carter, tax cuts, Reagan's Economic Bill of Rights, union busting, and the Iran-Contra among other things. Learn about Reagan's domestic and foreign policy initiatives, and even a little about Bonzo the Chimp.

Hey teachers and students - Check out CommonLit's free collection of reading passages and curriculum resources to learn more about the events of this episode. Ronald Reagan signalled a shift to conservative values on the role of government, discussed in his "Time for Choosing" Speech: https://www.commonlit.org/text....s/from-a-time-for-ch
America turned to President Reagan for comfort in times of tragedy, including following the Challenger Disaster: https://www.commonlit.org/text....s/ronald-reagan-on-t

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As the Roman Empire fell, so did the theater. If there's anyone who hates theater and actors more than Romans, it's early Christians. As Christianity ascended in the west, theater declined. But, fear not. This isn't the end of the series. Theater would be back, and in the best subversive theater-y fashion, it would return via the Catholic mass!

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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, Glenn Elliott, Justin Zingsheim, 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, 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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You might suppose this catfish is sick, or just confused. But swimming belly-up actually helps it camouflage and breathe better than its right-side-up cousins.

SUBSCRIBE to Deep Look! http://goo.gl/8NwXqt

DEEP LOOK: a new ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Get a new perspective on our place in the universe and meet extraordinary new friends. Explore big scientific mysteries by going incredibly small.

Normally, an upside-down fish in your tank is bad news. As in, it’s time for a new goldfish.

That’s because most fish have an internal air sac called a “swim bladder” that allows them to control their buoyancy and orientation. They fill the bladder with air when they want to rise, and deflate it when they want to sink. Fish without swim bladders, like sharks, have to swim constantly to keep from dropping to the bottom.

If an aquarium fish is listing to one side or flops over on its back, it often means it has swim bladder disease, a potentially life-threatening condition usually brought on parasites, overfeeding, or high nitrate levels in the water.

But for a few remarkable fish, being upside-down means everything is great.

In fact, seven species of catfish native to Central Africa live most of their lives upended. These topsy-turvy swimmers are anatomically identical to their right-side up cousins, despite having such an unusual orientation.

People’s fascination with the odd alignment of these fish goes back centuries. Studies of these quizzical fish have found a number of reasons why swimming upside down makes a lot of sense.

In an upside-down position, fish produce a lot less wave drag. That means upside-down catfish do a better job feeding on insect larvae at the waterline than their right-side up counterparts, who have to return to deeper water to rest.

There’s something else at the surface that’s even more important to a fish’s survival than food: oxygen. The gas essential to life readily dissolves from the air into the water, where it becomes concentrated in a thin layer at the waterline — right where the upside-down catfish’s mouth and gills are perfectly positioned to get it.

Scientists estimate that upside-down catfishes have been working out their survival strategy for as long at 35 million years. Besides their breathing and feeding behavior, the blotched upside-down catfish from the Congo Basin has also evolved a dark patch on its underside to make it harder to see against dark water.

That coloration is remarkable because it’s the opposite of most sea creatures, which tend to be darker on top and lighter on the bottom, a common adaptation called “countershading” that offsets the effects of sunlight.

The blotched upside-down catfish’s “reverse” countershading has earned it the scientific name negriventris, which means black-bellied.

--- How many kinds of fish swim upside down?

A total of seven species in Africa swim that way. Upside-down swimming may have evolved independent in a few of the species – and at least one more time in a catfish from Asia.

--- How do fish stay upright?

They have an air-filled swim bladder on the inside that that they can fill or deflate to maintain balance or to move up or down in the water column.

--- What are the benefits of swimming upside down?

Upside down, a fish swims more efficiently at the waterline, where there’s more oxygen and better access to some prey.

---+ Read the entire article on KQED Science:

https://www.kqed.org/science/1....922038/the-mystery-o

---+ For more information:

The California Academy of Sciences has upside-down catfish in its aquarium collection: https://www.calacademy.org/exh....ibits/steinhart-aqua

---+ More Great Deep Look episodes:

Take Two Leeches and Call Me in the Morning
https://youtu.be/O-0SFWPLaII

This Is Why Water Striders Make Terrible Lifeguards
https://youtu.be/E2unnSK7WTE

---+ See some great videos and documentaries from the PBS Digital Studios!

PBS Eons: What a Dinosaur Looks Like Under a Microscope
https://www.youtube.com/watch?v=4rvgiDXc12k

Origin of Everything: The Origin of Race in the USA
https://www.youtube.com/watch?v=CVxAlmAPHec

---+ Follow KQED Science:

KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

---+ About KQED

KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios. Deep Look is a project of KQED Science, which is supported by the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Fuhs Family Foundation Fund and the members of KQED.
#deeplook

What if you had to grow 20 pounds of bone on your forehead each year just to find a mate? In a bloody, itchy process, males of the deer family grow a new set of antlers every year, use them to fend off the competition, and lose their impressive crowns when breeding season ends.

SUBSCRIBE to Deep Look! http://goo.gl/8NwXqt

DEEP LOOK is a ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Get a new perspective on our place in the universe. Explore big scientific mysteries by going incredibly small.

* WE’RE TAKING A BREAK FOR THE HOLIDAYS. WATCH OUR NEXT EPISODE ON JAN. 17, 2017. *

Antlers are bones that grow right out of an animal’s head. It all starts with little knobs called pedicles. Reindeer, elk, and their relatives in the cervid family, like moose and deer, are born with them. But in most species pedicles only sprout antlers in males, because antlers require testosterone.

The little antlers of a young tule elk, or a reindeer, are called spikes. Every year, a male grows a slightly larger set of antlers, until he becomes a “senior” and the antlers start to shrink.

While it’s growing, the bone is hidden by a fuzzy layer of skin and fur called velvet that carries blood rich in calcium and phosphorous to build up the bone inside.

When the antlers get hard, the blood stops flowing and the velvet cracks. It gets itchy and males scratch like crazy to get it off. From underneath emerges a clean, smooth antler.

Males use their antlers during the mating season as a warning to other males to stay away from females, or to woo the females. When their warnings aren’t heeded, they use them to fight the competition.

Once the mating season is over and the male no longer needs its antlers, the testosterone in its body drops and the antlers fall off. A new set starts growing almost right away.

--- What are antlers made of?

Antlers are made of bone.

--- What is antler velvet?

Velvet is the skin that covers a developing antler.

--- What animals have antlers?

Male members of the cervid, or deer, family grow antlers. The only species of deer in which females also grow antlers are reindeer.

--- Are antlers horns?

No. Horns, which are made of keratin (the same material our nails are made from), stay on an animal its entire life. Antlers fall off and grow back again each year.

---+ Read an article on KQED Science about how neuroscientists are investigating the potential of the nerves in antler velvet to return mobility to damaged human limbs, and perhaps one day even help paralyzed people:

https://ww2.kqed.org/science/2....016/12/06/rudolphs-a

---+ For more information on tule elk

https://www.nps.gov/pore/learn/nature/tule_elk.htm

---+ More Great Deep Look episodes:

The Sex Lives of Christmas Trees
https://www.youtube.com/watch?v=xEji9I4Tcjo

Watch These Frustrated Squirrels Go Nuts!
https://www.youtube.com/watch?v=ZUjQtJGaSpk

This Mushroom Starts Killing You Before You Even Realize It
https://www.youtube.com/watch?v=bl9aCH2QaQY

---+ See some great videos and documentaries from PBS Digital Studios!

The REAL Rudolph Has Bloody Antlers and Super Vision - Gross Science
https://www.youtube.com/watch?v=gB6ND8nXgjA

Global Weirding with Katharine Hayhoe: Texans don't care about climate change, right?
https://www.youtube.com/watch?v=P_r_6D2LXVs&list=PL1mtdjDVOoOqJzeaJAV15Tq0tZ1vKj7ZV&index=25

It’s Okay To Be Smart: Why Don’t Woodpeckers Get Concussions?
https://www.youtube.com/watch?v=bqBxbMWd8O0

---+ Follow KQED Science:

KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

---+ About KQED

KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios and the John S. and James L. Knight Foundation. Deep Look is a project of KQED Science, which is also supported by HopeLab, the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Smart Family Foundation and the members of KQED.
#deeplook

Support Deep Look on Patreon!! https://www.patreon.com/deeplook

Because it's hoarding protein. Not just for itself, but for the butterfly it will become and every egg that butterfly will lay. And it's about to lose its mouth... as it wriggles out of its skin during metamorphosis.

DEEP LOOK is a ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Get a new perspective on our place in the universe and meet extraordinary new friends. Explore big scientific mysteries by going incredibly small.

* NEW VIDEOS EVERY OTHER TUESDAY! *

That caterpillar in your backyard is chewing through your best leaves for a good reason.

“Caterpillars have to store up incredible reserves of proteins,” said Carol Boggs, an ecologist at the University of South Carolina. “Nectar doesn’t have much protein. Most of the protein that goes to making eggs has to come from larval feeding.”

Caterpillars are the larval stage of a butterfly. Their complete transformation to pupa and then to butterfly is a strategy called holometaboly. Humans are in the minority among animals in that we don’t go through these very distinct, almost separate, lives. We start out as a smaller version of ourselves and grow bigger.

But from an evolutionary point of view, the way butterflies transform make sense.

“You have a larva that is an eating machine,” said Boggs. “It’s very well-suited to that. Then you’re turning it into a reproduction machine, the butterfly.”

Once it becomes a butterfly it will lose its mouth, grow a straw in its place and go on a liquid diet of sugary nectar and rotten fruit juices. Its main job will be to mate and lay eggs. Those eggs started to develop while it was a pupa, using protein that the caterpillar stored by gorging on leaves. We think of leaves as carbohydrates, but the nitrogen they contain makes them more than one quarter protein, said Boggs.

-- What are the stages of a butterfly?
Insects such as butterflies undergo a complete transformation, referred to by scientists as holometaboly. A holometabolous insect has a morphology in the juvenile state which is different from that in the adult and which undergoes a period of reorganization between the two, said Boggs. The four life stages are egg, larva (caterpillar), pupa (also known as chrysalis) and butterfly.

-- What if humans developed like butterflies?
“We’d go into a quiescent period when we developed different kind of eating organs and sensory organs,” said Boggs. “It would be as if we went into a pupa and developed straws as mouths and developed more elaborate morphology for smelling and developed wings. It brings up science fiction images.”

---+ Read the entire article on KQED Science:
https://ww2.kqed.org/science/2....017/07/11/why-is-the

---+ For more information:

Monarch Watch: http://www.monarchwatch.org

California Pipevine Swallowtail Project:
https://www.facebook.com/Calif....orniaPipevineSwallow
A forum organized by Tim Wong, who cares for the butterflies in the California Academy of Sciences’ rainforest exhibit. Wong’s page has beautiful photos and videos of California pipevine swallowtail butterflies at every stage – caterpillar, pupa and butterfly – and tips to create native butterfly habitat.

---+ More Great Deep Look episodes:

What Gives the Morpho Butterfly Its Magnificent Blue?
https://www.youtube.com/watch?v=29Ts7CsJDpg

This Vibrating Bumblebee Unlocks a Flower's Hidden Treasure
https://www.youtube.com/watch?v=SZrTndD1H10

Roly Polies Came From the Sea to Conquer the Earth
https://www.youtube.com/watch?v=sj8pFX9SOXE

In the Race for Life, Which Human Embryos Make It?
https://www.youtube.com/watch?v=9mv_kuwQvoc

---+ See some great videos and documentaries from the PBS Digital Studios!

PBS Eons: When Did the First Flower Bloom?
https://www.youtube.com/watch?v=13aUo5fEjNY

CrashCourse: The History of Life on Earth - Crash Course Ecology #1
https://www.youtube.com/watch?v=sjE-Pkjp3u4

---+ Follow KQED Science:

KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

---+ About KQED

KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios and the John S. and James L. Knight Foundation. Deep Look is a project of KQED Science, which is also supported by HopeLab, the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Smart Family Foundation and the members of KQED.
#deeplook #caterpillars #butterflies

Those hundreds of powerful suckers on octopus arms do more than just stick. They actually smell and taste. This contributes to a massive amount of information for the octopus’s brain to process, so octopuses depend on their eight arms for help. (And no, it's not 'octopi.')

To keep up with Amy Standen, subscribe to her podcast The Leap - a podcast about people making dramatic, risky changes:

https://ww2.kqed.org/news/programs/the-leap/

DEEP LOOK is a ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. Explore big scientific mysteries by going incredibly small.

SUBSCRIBE to Deep Look! http://goo.gl/8NwXqt

* NEW VIDEOS EVERY OTHER TUESDAY! *

Everyone knows that an octopus has eight arms. And similar to our arms it uses them to grab things and move around. But that’s where the similarities end. Hundreds of suckers on each octopus arm give them abilities people can only dream about.

“The suckers are hands that also smell and taste,” said Rich Ross, senior biologist and octopus aquarist at the California Academy of Sciences.

Suckers are “very similar to our taste buds, from what little we know about them,” said University of North Carolina, Chapel Hill, cephalopod biologist William Kier.

If these tasting, smelling suckers make you think of a human hand with a tongue and a nose stuck to it, that’s a good start. It all stems from the unique challenges an octopus faces as a result of having a flexible, soft body.

“This animal has no protection and is a wonderful meal because it’s all muscle,” said Kier.

So the octopus has adapted over time. It has about 500 million neurons (dogs have around 600 million), the cells that allow it to process and communicate information. And these neurons are distributed to make the most of its eight arms. An octopus’ central brain – located between its eyes – doesn’t control its every move. Instead, two thirds of the animal’s neurons are in its arms.
“It’s more efficient to put the nervous cells in the arm,” said neurobiologist Binyamin Hochner, of Hebrew University, in Jerusalem. “The arm is a brain of its own.”

This enables octopus arms to operate somewhat independently from the animal’s central brain. The central brain tells the arms in what direction and how fast to move, but the instructions on how to reach are embedded in each arm.

Octopuses have also evolved mechanisms that allow their muscles to move without the use of a skeleton. This same muscle arrangement enables elephant trunks and mammals’ tongues to unfurl.

“The arrangement of the muscle in your tongue is similar to the arrangement in the octopus arm,” said Kier.

In an octopus arm, muscles are arranged in different directions. When one octopus muscle contracts, it’s able to stretch out again because other muscles oriented in a different direction offer resistance – just as the bones in vertebrate bodies do. This skeleton of muscle, called a muscular hydrostat, is how an octopus gets its suckers to attach to different surfaces.

--- How many suction cups does an octopus have on each arm?

It depends on the species. Giant Pacific octopuses have up to 240 suckers on each arm.

--- Do octopuses have arms or tentacles?

Octopuses have arms, not tentacles. “The term ‘tentacle’ is used for lots of fleshy protuberances in invertebrates,” said Kier. “It just happens that the eight in octopuses are called arms.”

--- Can octopuses regrow a severed arm?

Yes!

---+ Read the entire article on KQED Science:

https://ww2.kqed.org/science/2....017/02/14/if-your-ha

---+ For more information:

The octopus research group at the Hebrew University of Jerusalem: https://www.youtube.com/watch?v=gN81dtxilhE

---+ More Great Deep Look episodes:

You're Not Hallucinating. That's Just Squid Skin.
https://www.youtube.com/watch?v=0wtLrlIKvJE

Watch These Frustrated Squirrels Go Nuts!
https://www.youtube.com/watch?v=ZUjQtJGaSpk

---+ See some great videos and documentaries from the PBS Digital Studios!

It’s Okay To Be Smart: Is This A NEW SPECIES?!
https://www.youtube.com/watch?v=asZ8MYdDXNc

BrainCraft: Your Brain in Numbers
https://www.youtube.com/watch?v=FFcbnf07QZ4

---+ Follow KQED Science:

KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

---+ About KQED

KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios and the John S. and James L. Knight Foundation. Deep Look is a project of KQED Science, which is also supported by HopeLab, the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Smart Family Foundation and the members of KQED.
#deeplook

It's an all-out brawl for prime beach real estate! These Caribbean crabs will tear each other limb from limb to get the best burrow. Luckily, they molt and regrow lost legs in a matter of weeks, and live to fight another day.

You can learn more about CuriosityStream at https://curiositystream.com/deeplook
Help Deep Look grow by supporting us on Patreon!!
https://www.patreon.com/deeplook

PBS Digital Studios Mega-playlist:

https://www.youtube.com/playli....st?list=PL1mtdjDVOoO

DEEP LOOK is a ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.

On the sand-dune beaches where they live, male blackback land crabs do constant battle over territory. The stakes are high: If one of these baby-faced crabs secures a winning spot, he can invite a mate into his den, six or seven feet beneath the surface.

With all this roughhousing, more than feelings get hurt. The male crabs inevitably lose limbs and damage their shells in constant dust-ups. Luckily, like many other arthropods, a group that includes insects and spiders, these crabs can release a leg or claw voluntarily if threatened. It’s not unusual to see animals in the field missing two or three walking legs.

The limbs regrow at the next molt, which is typically once a year for an adult. When a molt cycle begins, tiny limb buds form where a leg or a claw has been lost. Over the next six to eight weeks, the buds enlarge while the crab reabsorbs calcium from its old shell and secretes a new, paper-thin one underneath.

In the last hour of the cycle, the crab gulps air to create enough internal pressure to pop open the top of its shell, called the carapace. As the crab pushes it way out, the same internal pressure helps uncoil the new legs. The replacement shell thickens and hardens, and the crab eats the old shell.

--- Are blackback land crabs edible?

Yes, but they’re not as popular as the major food species like Dungeness and King crab.

--- Where do blackback land crabs live?

They live throughout the Caribbean islands.

--- Does it hurt when they lose legs?

Hard to say, but they do have an internal mechanism for releasing limbs cleanly that prevents loss of blood.

---+ Read the entire article on KQED Science:

https://www.kqed.org/science/1....933532/whack-jab-cra

---+ For more information:

The Crab Lab at Colorado State University:
https://rydberg.biology.colostate.edu/mykleslab/

---+ More Great Deep Look episodes:

Want a Whole New Body? Ask This Flatworm How
https://www.youtube.com/watch?v=m12xsf5g3Bo

Daddy Longlegs Risk Life ... and Especially Limb ... to Survive
https://www.youtube.com/watch?v=tjDmH8zhp6o

---+ See some great videos and documentaries from the PBS Digital Studios!

Origin of Everything: The Origin of Gender
https://www.youtube.com/watch?v=5e12ZojkYrU

Hot Mess: Coral Reefs Are Dying. But They Don’t Have To.
https://www.youtube.com/watch?v=MUAsFZuFQvQ

---+ Follow KQED Science:

KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

---+ About KQED

KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios. Deep Look is a project of KQED Science, which is also supported by the National Science Foundation, the Templeton Religion Trust, the Templeton World Charity Foundation, the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Fuhs Family Foundation and the members of KQED.

---+ Shoutout!

Congratulations to ?Jen Wiley?, who was the first to correctly ID the species of crab in our episode over at the Deep Look Community Tab:

https://www.youtube.com/channe....l/UC-3SbfTPJsL8fJAPK

#deeplook #pbsds #crab

Poema de D. Pedro Casaldáliga musicada pelo Grupo Kairoi da Espanha. Uma forma bonita de fazer memória de Maria.