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It's Green vs. Green in this week's quiz show as Hank battles Katherine to see who takes home all the marriage points.

Hosted by: Michael Aranda

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Coconut Water

Project X-Ray



Diving Humans

 (00:00) to (02:00)

Thanks to SkillShare for supporting this SciShow Quiz Show.


Michael: Ladies and gentlemen and non-binary friends, welcome to SciShow Quiz Show, the only quiz show where I, Michael Aranda, am standing in between a married couple about to fight to the death.  In this corner, we have Hank Green.

Hank: Like a thumb fight to the thumb de--like, what kind of death?

M: I don't know.  Let's find out together.

H: Is this what the script says?

M: In this corner, we have Hank Green, who's very passionate about digestive health on Twitter and getting that #spon from Metamucil.

H: Trying my best.  Invest in your digestion!  Oh, that kind of rhymes a little.

Katherine: Yeah, you're welcome for that one.  Yeah.  It's always me.  Best material.  

M: In this corner, he's facing off against Katherine Green, who critiques Hank's Tweets about poop and politics and all kinds of things in their weekly podcast Delete This.  

K: Yes, I am critical.

M: As a special thanks to our Patrons on Patreon, we're randomly selecting two of you to win some cool prizes.  Hank, you're playing for Hubert Rady.

H: Hey.  Congratulations, Hubert, on your random selection.

M: Katherine, you're playing for Jess Graham.

K: Alright, Jess, let's do it.

M: Stefan.  Show our contestants what they can go home with today.

Stefan: Hubert and Jess, are you ready?  You're gonna be taking home autographed answer cards from the final round today.  If you're the winner of the show, you're gonna walk away with a brand new car, and by brand new car, I mean you're gonna get the 'I Won SciShow Quiz Show' pin, but you can pretend you're driving a brand new car by turning the pin back and forth like a steering wheel, and we'll also throw in some super top secret ultra-special limited edition SciShow swag from  But if you're the loser of the show today, you'll still be getting a great value, the 'I Lost SciShow Quiz Show' pin is quite a stunning piece and these babies are gonna start showing up on eBay in about 10-20 years, so start saving now.  But that's all I've got for you today, so back to you.

M: Now, you both start off with 1000 marriage points.  

 (02:00) to (04:00)

K: Uh-oh.

M: Each time you answer a question correctly, you'll win 200.  If you get it wrong, you'll lose 100.  

H: What happens if we get to 0 marriage points?  

K: And then if we get to 0, we have a divorce?  Is it just, that's it?  

H: Let's not find out.  

K: So the death of our marriage, that's what we're fighting to.  Oh shoot.  

M: Okay, round number one is all about green stuff, which I expect both of you are experts in.  Here's the first question.

H: That's our last name.  

K: Wow.  Okay.

H: Did you get the joke?

K: Yeah.  I got it.  I got it.

H: Okay, just making sure.

K: Okay.  Yeah.  

M: I love this.  Everyone loves a good potato, whether it's mashed or fried or chuked up in a stew.  They're tubers, basically thick nutrient-filled stems that normally grow underground, but if potatoes are exposed to sunlight and warmth, they'll start producing other chemicals like chlorophyll, which turns them green and helps with photosynthesis.  You don't want to eat a green potato though because of another compound it makes.  What does this chemical do: it's a pesticide which would poison you, it's a hallucinogen which would make you have a very bad trip, it's an insulin analog which would drop your blood sugar to dangrous lows, or it's a virus-like protein which causes an immense immune response?  

H: What was the first one?  I think it's that.

M: It's a pesticide which would poison you.

H: Yeah.  Yeah, let's go with that.

M: That is correct.

H: Yay!

K: I forgot about the buzzing in thing.  

H: You're waiting to say your answer.  

K: Yeah, I gotcha.

H: What did you think it was?

K: Uh, that one.  

H: Okay.  Well, sorry, I got 200 points and you didn't.

K: That's alright.  You've got a little something over here.  

H: Oh.  Thanks.

K: Yeah.

H: Guys.  Why do we have to have Katherine give me last looks?  

K: Nobody wants to look at you.  They're just tired.  They're just tired of seeing your face all the time.

H: They do see me a lot.

K: I know.

H: That's true.  

K: Not in here, huh?

S: The answer is A, a pesticide.  Sunlight stimulates more synthesis of a chemical called solanine, a bitter toxin that helps protect potatoes from being eaten by insects and other hungry critters. 

 (04:00) to (06:00)

Specifically, solanine is a glycoalkaloid that's found in a bunch of plants in the nightshade family, which includes deadly nightshade along with things we actually eat like tomatoes and potatoes.  We're not exactly sure how this compound messes with our cells.  Some studies suggest it can disrupt cell membranes or interfere with an enzyme called cholinesterase, which affects how neurons and muscle cells communicate.  So if humans eat enough solanine, it can get pretty unpleasant, with things like stomach problems, burning feelings in your throat, and headaches.  With a high enough dose, it can be fatal, too.  Most of the solanine synthesis happens near the potato skin, though, so as long as you cut away the surface and especially any green parts, you'll be fine, but you might wanna stay away from any green french fries.

M: Question two.  Absynthe is nicknamed 'the green fairy' for its color and popularity as a drink with French artists in the 1800s.  It's made from a kind of wormwood, and there are other species of this shrub that are known to have medicinal benefits.  So absynthe was given to French soldiers during their colonial wars in the 1830s and 40s.  Look at these hands slowly inching towards the button.

K: Just sneakin' in here.  

H: Okay.

M: So absynthe was given to French soldiers during their colonial wars in the 1830s and 40s to try to prevent disease. What, specifically, were they trying to protect against?  Depression, schizophrenia, malaria, or syphilis?

K: Where were they?

M: French soldiers during their colonial wars.

K: Yeah, malaria.

M: That is correct.

K: Yeah.

S: The answer is C, malaria.  Absynthe probably didn't help prevent malaria, although the French soldiers' reasoning wasn't completely flawed.  Absynthe wormwood doesn't have anti-malarial compounds, but its cousin sweet wormwood does.  In fact, Chinese doctors had been treating malaria with tea made from sweet wormwood for thousands of years.  The active ingredient is called artemisinin, which was isolated in the 1970s.  It seems to work by binding to heme, the iron-containing compound that's a part of hemoglobin, and interfering with a bunch of different chemical pathways that the malaria parasite needs to survive.  Like with many anti-microbial treatments, scientists are worried that an artemisinin-only approach will lead to parasites that adapt to be resistant to the chemical, so it's still being used today, but mostly in combination with other anti-malarial drugs.

 (06:00) to (08:00)

M: This next round is about more conflict-related science, specifically some unusual stuff that happened around World War II.  So here's the first question.  Coconut water.  That clear liquid inside of coconuts seems like just another hip drink fad because people are making all sorts of health claims about it.  It does have sugars, vitamins, and ions like sodium and potassium, which make it almost like a sports drink, and during World War II, when medical supplies were scarce, both British and Japanese soldiers supposedly used coconut water for an emergency treatment.  What was it used for?

H: What--which--where did they put it?  

K: Just--vague--just--just--

H: No, there's answers.  

K: Oh, okay, alright.

H: I was just curious which end it went in.

M: I'm just reading the script, man.

H: Okay.  

M: Was it used for a disinfectant for traumatic injuries, a sterile enema solution--

H: Ah, see!  

K: He's very interested in butt health.  

M: As a numbing agent to help with amputations, or as a saline substitute to prevent dehydration?

K: D, it's that last one.

H: D, is it D, the last one?

M: That is correct.

H: Ah, dang it!  I wasn't gonna guess that.  

K: You gotta jump on it.  You gotta jump on it.  

H: I would have guessed like, I don't know, one of the other ones.

M: An enema  You were gonna go for the enema.

H: Sterile enema solution.

K: No, no, they're putting that all up in them.  Inside.  

H: Yeah, this way.

K: Right in it.  

H: Oh, in this way?

K: I dunno.  It said saline.

H: It's true.  Did they put it in their veins?

K: Maybe.  

S: The answer is D, as a saline substitute.  When people get severely dehydrated or lose blood, doctors can use intravenous or IV therapy to get fluid back into the body.  IV therapy typically involves saline solutions with different compositions, water, sugars, ions, and other nutrients usually at similar concentrations to blood.  Our cells especially need ions like sodium and potassium for basic chemical functions, so in a pinch, some World War II soldiers reportedly used coconut water as an IV solution to replenish those compounds, rehydrate, and survive.

 (08:00) to (10:00)

But modern scientists say this is probably pretty dangerous.  That's because, unlike carefully made saline solutions, coconut water doesn't have the right balance of chemicals.  It doesn't have enough sodium and has too much calcium and potassium, which could throw off cellular systems, so just stick to drinking it for a little refreshment.  That's way safer.

M: So you've probably heard of homing pigeons, but what about project pigeons?  An American psychologist named BF Skinner knew pigeons had keen vision, were unflappable under pressure, and could be carefully trained.

H: Unflappable.

K: Mhmm.  

M: Mhmm.  Mhmm.  

K: Mhmm.

M: Long story short, in 1943, he designed a missle cockpit so three pigeons could mechanically steer it toward a target by recognizing visual patterns on screens and pecking at them.  

K: This is true?  

H: That's not true.

K: This is the truth?  

H: That's not true.  

M: Despite progress, the US National Defense Research Committee pulled finding by October of 1944, but surprisingly--

H: No vision!

M: --this wasn't the only animal-based bomb in development.

K: No pigeon vision.  Yo.

M: One project, called Project X-Ray, was designed to target buildings.  It involved dropping casings with living animals in them from planes.  What was inside those casings?  Pigeons with blast bombs implanted in them, rats with electromagnetic pulse weapons implanted in them, bats with incendiary bombs attached to them, or crows with radioactive cluster bombs attached to them?

K: What?

H: Oh, it's gotta, it's gotta be C, right?  It's gotta be bats.

M: That is correct.

K: Aw, phew.  

S: The answer is C, bats with fire bombs.  In 1941, a dentist named (?~9:45) S. Adams was on vacation at the Carlsbad Caverns in New Mexico, where there are hundreds of thousands of Brazilian free-tailed bats.  It was the middle of World War II and the Pearl Harbor attack had just happened, so inspiration struck, and eventually, he ended up working with the National Defense Research Committee and a scientist who specialized in bat echolocation on what was called Project X-Ray, even though there weren't any x-rays involved.

 (10:00) to (12:00)

The goal was to deploy these bats with tiny time-based incendiary bombs attached to them, so they'd roost in nearby attics and barns and burn buildings down.  To do that, they stuck bats in ice cube trays to cool them down and make them hibernate, drop them in refrigerated casings from an airplane, and release them.  Then the bats would wake up in mid-air, get confused, and find somewhere cozy and dark to rest.  Soon after, the fire bombs would go off.  The researchers tested this system on a US military base in 1943 and saw how destructive these bats could be.  In the end, funding for this project was dropped in 1944.  They didn't want to trust these bat bombs and poured resources into other military tech instead.

M: This first question is all about shellfish, not the clams that know how to jam, but mussels.  Marine--

K: Oh my God.  Swole.  Swole.  Sleepy and swole.  

H: Sweepy.

M: Marine scientists use bivalves like mussels to help track contaminants in ocean water.  They're filter feeders, which means they suck in water and strain out anything edible, but they pick up other chemicals, too, which get incorporated into their tissues.  In May 2018, the Puget Sound Mussel Monitoring Program in Washington State discovered something new about a few populations of local shellfish.  Was it: they were stained blue from synthetic food dyes, they tested positive for oxycodone, they had a high concentration of ethanol, or they had multiple pearls inside?  

H: I'm gonna say that those clams were on oxy.  

M: That is correct.

K: Dang it.  I wanted them to be blue.  

H: Yeah, me too.  I would prefer that.  Or extra pearls.

K: Yeah.

S: The answer is B, they tested positive for oxycodone.  This discovery made the rounds on the internet with headlines like "Puget Sound Mussels Are Failing Drug Tests".  Every two years, researchers stick uncontaminated mussels throughout Puget Sound for a couple months.  Then they blend the shellfish tissues up and analyze the goop for chemical pollutants.

 (12:00) to (14:00)

It's not shocking that traces of illicit drugs are floating around, but this was the first time oxycodone was detected in mussels, specifically in 3 of the 18 sites they tested.  The researchers say the amount of oxycodone was much less than a normal dose, like thousands of times lower, but they also found high levels of a chemotherapy drug, antibiotics, and other medications that come out in our pee.  The shellfish don't seem to metabolize these chemicals, but researchers are more concerned about what's happening to fish.

Studies have shown that fish can change their behavior if they're exposed to drugs like opioids, so we've gotta keep a close eye on what we're accidentally adding to the oceans.

M: Speaking of fish, they are the star of this next question.  Fish need lots of ways to communicate with each other underwater, to swim in schools, find a mate, or scare off predators, and guppies are no exception.  In fact, a recent study showed that they have a cool way of signaling aggression to each other, like if they're ready to compete over food.  What do they do?  They blow up their forehead like a squishy battering ram--

H: Oh my God.

M: --they flare out all their sharp scales, their eyes change color from silver to black, or they ooze blood from special pores?  

K: I'm gonna go with C.  Their eyes change color.

M: That is correct.

H: Whoa!  I wasn't gonna guess that.  Thank you for saving me from myself.  I thought their head was gonna get puffy.  I liked the puffy head one.

S: The answer is C, their eyes turn black.  It almost sounds like a videogame boss, but these guppies actually darken their irises when they're ready to fight.  This phenomenon is called dynamic eye color, and the researchers aren't entirely sure how it works on a cellular level.  They think these fish may be constantly suppressing eye cells that contain dark pigments, and when they get aggressive, their nervous system changes the cell sizes.  To test how guppies respond in different social situations, the scientists made different sizes of robot guppies with both silver and black eyes.  They found that the guppies were likely to fight a silver-eyed robot that's bigger than them for food, because they want to show dominance, or they'll get aggressive with a black-eyed robot that's smaller because they're being challenged.  Basically, the researchers think these fish only turn their eyes black if they think they can actually stand a chance in a fight, which kind of makes sense, because you don't want to just go out and start tussling with every fish you lay eyes on.

 (14:00) to (16:00)

M: Okay, we've reached our final question.  This means that both of you get to wager any or all of your points on your correctness to the next answer.  

H: Well put.

M: You both have 1600 points.  

K: Uh-huh.  Uh-huh.

M: And I can tell you that this question is kind of about mermaids, or at least humans under the sea.  

K: Okay.

M: While you place your bets, we're gonna go to commercial break maybe.

Okay, so the theme of the final round is ocean life, so we decided to lean into that when talking about SkillShare, too.  No matter what you're interested in, you can most likely find a class about it on SkillShare.  This class on Simplifying Raw Fish, taught by Chef Ken Oringer, aims to make you a sushi master in your own home.  Oringer is a James Beard Award winning chef and he draws on his years of experience cooking around the world to teach you how to safely prepare delicious sashimi, (?~14:57), and ceviche.  Working with raw fish is intimidating, but this class takes the guesswork and fear out of learning how to do it yourself.  Plus, what's better than a class project you can eat and share with your friends?  To learn more about this class and the thousands of other SkillShare offers, follow the link in the description.  Right now, SkillShare is giving SciShow viewers two months of unlimited access to all their classes for free, so check it out and let us know what classes you're excited about, and now let's see who between Hank and Katherine is the more superior Green.

Welcome back, probably.  So, they're placed their bets.  You guys ready?  

K: Ready.

H: I'm ready.  

K: I guess.

M: The indigenous Bajau people live in Southeast Asia and have a culture built around the ocean.  They use handheld equipment to catch fish and shellfish and hold their breath for deep dives tens of meters down that can last for several minutes each.  This can mean hours spent underwater each day.  Typically, having enough oxygen to keep tissues alive is a limiting factor for diving, but in a paper published in April of 2018, researchers learned that the Bajau seem to have key genetic and physical changes to help them manage that lack of oxygen.

 (16:00) to (18:00)

What's the most significant change they found?  Bigger spleens, more powerful heart muscles, a special protein circulating in the brain, or overactive stem cells in bone marrow?  So you'll write your answer on your card.

H: I have no idea.  Those all seem equally likely.

M: We'll show them to the camera.

K: I don't.

H: I don't know either.

K: I got no--I got nothin'.  This is not where I thought this question was going.

H: So they're turning into mermaids is what you're saying.  Alright, I wrote down an answer.

K: Me too.

M: Alright.  Reveal your answers.  

K: I'm glad that I bet 0.

H: Oh.  We guessed the same thing.

M: Well.

H: We're both wrong.  

M: You have zero marriage points now.

H: I went down to zero marriage points.

K: Uh-oh.

H: Luckily, you're holding on to all of the marbles, so you just get to decide what to do with those.  

M: I think that makes Katherine Green our winner for today's SciShow Quiz Show.  The correct answer was bigger spleens.

H: Bigger spleens!

K: Ah, that was the one I dismissed.

H: That was right at the bottom of my list.

K: Just, yeah, exactly, yep.

S: The answer is A, bigger spleens.  This team of researchers compared the genomes and ultrasound measurements of the Bajau people to the Saluan people, a nearby population that doesn't dive, and the biggest difference between them was spleen size.  The Bajau peoples' spleens were 50% bigger than the Saluan peoples'.  Your spleen filters blood for a few reasons, like to help break down old blood cells, recycle any useful proteins, and store extra blood in case of an emergency.  A sudden lack of oxygen, called acute hypoxia, during a long deep dive could be seen as one of those emergencies, so an extra burst of oxygenated red blood cells could help keep tissues alive, and a bigger spleen can store and release more oxygenated red blood cells to help keep everything working smoothly under extreme conditions.  There was a genetic basis for this change, too, which explains why all Bajau people, not just the ones who dive, seem to have beefy spleens.  The researchers found different versions of a gene that helps regulate thyroid hormones, which are known to influence spleen size, and they found variants in other genes, too, like one that controls blood vessel constriction in the extremities to help make sure vital organs have enough oxygen.  

 (18:00) to (18:48)

So even though it feels like there are plenty of mysteries about the deep ocean, there are some hiding in human DNA, too.

M: Thanks for joining us for this SciShow Quiz Show, and thanks to all of our Patrons on Patreon.  If you'd like to support the show and get a chancet to be represented on our next show, you can go to and if you want to check out more of Hank and Katherine together, you can go listen to Delete This on your favorite podcast platform of choice.

K: Yeah, you know, or whatever.

H: Or don't.  

K: It's fine.