Previous: The Hardcore Crickets That Only Live on Bare Lava
Next: How to Find Thousands of Oceanic Fossils in... Ohio?



View count:71,706
Last sync:2022-11-26 10:15
Einstein’s general theory of relativity was confirmed one hundred years ago today. Go to to take a theatrical journey with physicist Brian Greene and explore this discovery in LIGHT FALLS on PBS.

Hank faces off against Minute Physics's Henry Reich in a battle of eccentricities, fashion, and plant puns.

Hosted by: Michael Aranda

SciShow has a spinoff podcast! It's called SciShow Tangents. Check it out at
Support SciShow by becoming a patron on Patreon:
Huge thanks go to the following Patreon supporters for helping us keep SciShow free for everyone forever:

Adam Brainard, Greg, Alex Hackman, Sam Lutfi, D.A. Noe, الخليفي سلطان, Piya Shedden, KatieMarie Magnone, Scott Satovsky Jr, Charles Southerland, Patrick D. Ashmore, charles george, Kevin Bealer, Chris Peters
Looking for SciShow elsewhere on the internet?
Eccentric orbits

Baking powder

Everything is grass$file/biologybanana08.pdf

Weird, weird frogs


Sneaky beetle

 (00:00) to (02:00)

Thanks to Light Falls on PBS for supporting this episode.  Light Falls premieres on May 29th at 10PM on PBS.  Go to to learn more.


Michael: It's time for SciShow Quiz Show, the only quiz show hosted by me immediately after eating a bunch of Mexican food.  Ooh.  

Hank: Chipotle.

Michael: In this corner, we have our resident Floridian who is still managing to thrive in all this snow, Hank Green.  

Hank: My nose hurts.  

Michael: And Hank is competing against Henry Reich, the brains and artist behind MinutePhysics and MinuteEarth.  After more than four years, he's back for another Quiz Show.  

Henry: It took that long.

Hank: How did you do last time?  

Henry: I think you lost.  I didn't win, but you lost is my recollection.

Michael: Last time, Henry won approximately 400 to 0.  

Hank: Sounds like we both did pretty bad.  

Michael: As a thank you to our supporters on Patreon, we've selected two of you at random to win some prizes.  Hank, you're playing for Margaret Sy.

Hank: Hello, Margaret.

Michael: And Henry, you're playing for Alex Ciminian.  

Henry: Hello, Alex.  

Michael: Stefan, show our contestants what they can go home with today.

Stefan: Hello!  Come with me!  Let's go this way!  Where to, you ask?  Well, it's the prize zone!  Alright, let's get down to business.  Alex and Margaret, you're not gonna have to fight over the autographed wager cards from our final round today, because we've got two of those, but you're gonna have to duke it out to find out who's gonna get the extremely shiny 'I Won SciShow Quiz Show' pin and one tote bag full of SciShow swag from, though we don't actually have any tote bags, so moving on.  If you're the contestant with the least points at the end of the show, you'll still be the recipient of a slightly less shiny, but very distinguished looking 'I Lost SciShow Quiz Show' pin, except it's not actually less shiny at all, because they were both forged from the same button maker.  Alright, you've seen enough.  Now get outta my zone!

Michael: Thank you, Stefan.  You both start out with 1,000 points.  Each time you choose a correct answer, you'll win some.  If you're wrong, you lose some.

 (02:00) to (04:00)

Henry: That makes the 400 points sound pretty bad, doesn't it?

Michael: Our first category is eccentric science.  Here's the first question.  Most things don't orbit the sun in a perfect circle.  Instead, their orbits have some degree of eccentricity.  In other words, they're somewhat oval shaped.  The question is, although there are more eccentric orbits out there, which one of these four objects has the most eccentric orbit: Mercury, Uranus, the dwarf planet Haumea, the dwarf planet Ceres?  

Hank: I'm gonna go with with Haumea.  That's--aughh, I got it wrong.  

Henry: The light stays on.

Hank: Well, it does eventually go off if you hit it right.

Henry: I'm gonna guess the other dwarf planet.  

Hank: Ceres?

Michael: That is also incorrect.

Hank: Also--is it Uranus?  

Michael: It is Mercury.

Hank: Oh my God.  That's not what I would have expected at all.

Henry: I mean, I guess, like, Einstein did--they tested the (?~2:53) of Mercury, so it must have some (?~2:57)

Michael: Exactly!

Hank: Henry knew something about this.

Henry: But who knows anything about like, the eccentricity of dwarf planets?

Michael: Right?

Olivia: Mercury's orbit has an eccentricity around 0.21.  In other words, it's about 20% of the way between a perfect circle and a parabola.  That might not sound like much, but it's surprisingly high.  For comparison, Ceres has an eccentricity of about 0.08.  Even Uranus and Haumea
, which, as members of the outer solar system, tend to have pretty weird orbits, only have eccentricities of 0.05 and 0.19 respectively.  Scientists think there's probably more than one reason Mercury's orbit is so oval shaped and it's only been in the last ten years or so that we've started to really figure out what's been going on.  Based on computer simulations, it looks like the factors involved include gravitational tugs from Jupiter and Venus and even effects of general relativity, Einstein's famous theory about how gravity works.  What's also interesting about these simulations is that they can show us how much Mercury's eccentricity can change over millions of years.  

 (04:00) to (06:00)

because of how all these factors play together, there's even a chance that its orbit could get so eccentric that it crosses venus's orbit.
if that happens it probably won't be for hundreds of millions of years though and statistically speaking, that also likely doesn't mean those planets are ever going to collide. but it just goes to show how would normal doesn't mean that much in the solar system.

Michael: our next question is about eccentric baking ingredients except this time it's not an offecial term,
baking powder is used to puff up various breads and pastries, in a pich you can make your own by combining baking soda with some cream of tartar.
but for hundreds of years, cooks used something else
what was their baking powder substitute?
b)pine needles
c)deer antlers ,or
d)chicken feathers

Henry:I'm gonna guss charcoal
Michael:I'm sorry Henry
Hank: I feel like I'm doing a lot of guessing right now, hundreds of years huh, what did we have for hundreds of years?
Michael: Is there any scishow quizshow where we're not just guessing the whole way through
Hank: what did you say is it hundreds or thousands?
Hank: okay we've had chicken feathers for hundreds of years and deer antlers, we've had all those things for hundreds of years
I feel like deer antlers
Michael: you're correct!
Hank:yaaaay! I just felt like it
Henry: what's the leavening agent in deer antlers?
Hank: calcium something.. it's just bones

Using deer antlers to puff up your bread seems pretty weird, but bakers used to do it all the time.
they called it hartshorn. and chemically speaking it totally makes sense.
commercial baking powder is a mixture of sodium bicarbonate aka baking soda along with two powderized acids
when these acids become wet or are exposed to heat, like from the oven, they react and create bubbles  that make everything all soft and fluffy
hartshorn does something similar
when you grind it up and heat it, it creates ammonia and carbon dioxide

 (06:00) to (08:00)

Which makes bubbles and puffy pastries just like baking powder.  Now, if you're thinking, I've watched enough episodes of this show to know that ammonia in food is a terrible idea.  Yeah.  You're right.  Thankfully, using hartshorn isn't dangerous because significant amounts of the chemical don't linger in the food once it's cooked.  The smell, on the other hand, which is reminiscent of smelling salts, is a lot harder to get rid of.  So thanks for saving us from that, baking powder.  

Michael: Our next round is called Which of these things is not like the others?  It's pretty self explanatory.  Question 3, as it turns out, a surprising amount of things in the plant kingdom are actually part of the grass family.  

Hank: Okay.

Michael: Which of these is not: Corn, banana plants, rice, or giant bamboo?

Hank: I'm gonna say bamboo isn't a grass.  I was wrong.

Michael: That is incorrect.  Shouldn't have said that.  

Henry: I'm gonna go with bananas.  

Michael: That is correct.  

Hank: Ahhh.  Okay.  I guess that makes sense.  I guess that'd be a weird thing for a grass to do.  

Henry: The whole, like, (?~7:04)

Hank: Have just a banana on it.

Henry: That's probably the--should have been the giveaway, huh?

Hank: Yeah.  

Henry: I was expecting bear grass to be on there because bear grass isn't a grass, but it's called a grass.  There's also a lot of like, sedges that aren't grasses, too, but that would be maybe a little bit too in the weeds.  That was unintended.  Apologies to everyone.  

Olivia: The grass family officially called poaceae is surprisingly large and it contains more than 5,000 different species of plants, which explains why some things that don't totally look like grass actually are biologically speaking.  These species often have round stems, leaves with parallel veins, and generally produce small flowers and they can live either in wet or dry areas which explains why rice, giant bamboo, and corn all fit the bill.  The only example on that list that wasn't grass was banana plants.  They're from a different, much smaller family native to Africa and Australia and they're technically an herb.

 (08:00) to (10:00)

Michael: Oh my goodness, how did this iPad get here?  This next one is a visual question.

Hank: Okay.

Michael: Looking at these four species, which of them is not a frog or toad: grumpy rock, purple blobs, red-eyed dude, or speckled bubble?

Henry: C.

Hank: Red eyed dude?  I would have gone with red eyed dude, too.  Ohh.

Michael: You are correct.

Henry: The fins.  

Hank: The fins.  The fins gave it away.  

Henry: The non-toady shape somehow doesn't even look like a tadpole.

Olivia: Okay, can we all just agree that the animal kingdom spits out some pretty stuff?  Alright, great, thanks.  The first picture is a black rain frog.  Like other rain frogs, it looks like an adorably disgruntled rock, but it's actually a frog.  They mainly live in South Africa and spend their days burrowing and despite their name, avoiding bodies of water.  The second is a type of pig-nosed frog that lives in India.  I swear it's not a slimy mutant seal.  There are a few different species of them and they probably have their unique look because they spend almost their entire lives underground.  They use their shovel-like limbs for digging and their snouts for sniffing out ants and termites.  The only time they grace the surface world with their presence is during monsoon season, when the rain drives them out of their holes.  The fourth picture is maybe the most frog-like of the four and it's Australia's crucifix toad or holy cross frog, named for the pattern of spots on its back.  Finally, our frog impostor is just a mudskipper, a kind of amphibious fish that can breath in both water and air, which is amazing in its own right.

Michael: We've got one category and two questions left.  It's currently 1200 to 1000.  This next category is Insect Fashion Accessories.  

Hank: Oh, good, good.  

Michael: A type of caterpillar called Uraba lugens is probably best known for its bizarre choice of hat.  The caterpillar has a collection of little black spheres stacked on top of its head which it seems to wear proudly.  Some people have even nicknamed it "The Mad Haterpillar".

 (10:00) to (12:00)

But the question is, what are their hats made of?  Is it--

Hank: They're not made of caterpillar? I thought they were just made of caterpillar.  

Michael: Like the dead bodies of their fallen comrades?

Hank: No, like, it just grew out, it grew out of their heads.

Henry: It's like, it appears to be a hat but actually a growth.  

Hank: Like, like your hair.  If I were a caterpillar, I'd probably be like, where'd you get that hat?

Michael: It's the dead bodies of my fallen comrades.  Is it a type of mold, their discarded exoskeletons, exoskeletons of their prey, or symbiotic bacteria?

Hank: I'm gonna say it's mold.  I was--God, why did I say that?

Michael: Incorrect.

Hank: I'm going to stop saying things.  

Henry: We don't get to see a picture, huh?  It'd be much easier with a picture.  

Hank: I want to see a picture of this dumb caterpillar.

Michael: There's one on the screen right now.  

Henry: Oh, then it must be discarded exoskeletons.

Hank: Ohhh!  

Michael: That's--that's the thing.  That is--that is correct.

Olivia: Like other kinds of caterpillar, Uraba lugens molts as it grows.  When it gets too big for its exoskeleton, it dramatically casts off to reveal a new one.  Okay, maybe not dramatically, but it's kind of fun to picture.  Strangely, though, this insect doesn't get rid of all of its exoskeleton.  It keeps the part that covered its head.  Over time as the caterpillar keeps growing and molting, these exoskeleton heads keep piling up, each of them attached to the head below it, and since these insects can molt more than a dozen times before they form coccoons, they can end up with quite a collection of hats.  Scientists are still investigating why exactly they do this, but based on experiments, they think it might be a great defense mechanism.  In one 2016 experiment, they found that in a group where some caterpillars had hats and others didn't, the ones with headgear were more likely to survive being intact because they use their hats as a sort of shield.  Talk about functional fashion.

Michael: It's time for the final question.  Time for you to place your bets on your answer to this final question, but before you do, I'll tell you that the question is about sneaky beetles.  

 (12:00) to (14:00)

While they place their bets, we're gonna go to commercial break.  

Stefan: Hi.  I want to tell you about Light Falls.  It's a 90 minute play written and performed by physicist Brian Greene, along with a full cast of Broadway veterans and uses animations and projections to help illustrate the journey that Einstein took to develop his general theory of relativity.  It has a very cool presentation style where the actors are interacting with the animations happening behind and in front of them to help you visualize and understand the concepts, and it premieres today, May 29, because this is the 100th anniversary of the confirmation of the general theory of relativity.  So check it out tonight, May 29, at 10PM on PBS,, and the PBS Video App, and if you miss the broadcast, you can always stream it over at  

Michael: And welcome back.  Okay, you guys ready?

Hank: I mean, as I'll ever be.  

Michael: Army ants are notoriously vicious.  They form huge swarms that seem to eat basically anything and they can trample many insects in their path, but one type of histerid beetle doesn't need to worry because they found a clever and rather fashionable way to stay safe.  What is it?

Hank: Hats?

Michael: They wear army ant exoskeletons on their backs.

Hank: That's pretty good.

Michael: They hold up leaves and hide behind them, they change color to look more like a ladybug, or they pretend to be army ant butts.  

Hank: Pretend to be army ant butts.  I don't know the answer to this one.  

Henry: I don't either.

Hank: I hope Henry bet all of his points.  

Michael: Well.

Henry: You have in a one in four chance.

Hank: Of what?  You betting all of your points?  

Henry: No, of--

Hank: I feel like I have a much lower than that chance.

Henry: Of answering correctly.

Hank: Yes, correct.  

Henry: And then there's like a one in four chance of me answering correctly also but.

Hank: So as I could make it.  I could (?~13:56)

Henry: We could do some complicated math to figure out what the chances are.  

Hank: Okay.

Michael: Okay.  You guys ready? 

 (14:00) to (15:45)

Reveal your answers.  

Hank: They do number A.

Michael: It looks like Henry is correct.  So once again, Henry is the reigning champion of SciShow Quiz Show.

Hank: Aw, man.

Michael: Hoo boy.  

Hank: I'm down to zero points.

Henry: Congratulations, Alex, for your ant butt.  

Olivia: This type of beetle was first described in 2017.  It's pretty tiny, only about a millimeter and a half long, and has a little round body and a hard shell, and that shell really comes in handy, because this beetle lives a pretty hardcore life.  It hangs out exclusively with one species of army ant and spends its days mooching off the ants for food and transportation, but this isn't a mutually beneficial relationship.  It doesn't seem like the beetles provide anything in exchange for their meals.  Instead, scientists think they just rely on their shells for defense in case someone realizes what's going on, but that isn't the beetles' only trick.  These army ants are also nomadic, migrating a couple of times every month in search of greener pastures, and the beetles have found a way to hitch a ride.  When it's time to go, they bite down on an army ant's waist and hang on like a fanny pack until they've arrived at their new location.  If you don't look too closely, you might even mistake them for an extra butt, which means other ants might not realize they're giving these moochers a lift.

Michael: Thanks for watching this episode of SciShow Quiz Show.  If you want to see more of Henry, or at least of the drawings that he makes, you can check out his work at and if you want to support SciShow and get a chance to compete on SciShow Quiz Show, you can go to  

Hank: Whoo!