Hank: Hello, and welcome to the SciShow Talk Show, the episode of SciShow where we talk about things with interesting people. We have a very special guest today, this is Derek Muller, from the channel Veritasium on YouTube.

Derek: Thank you for having me.

H: What the heck do you do?

D: I make videos about all sorts of science, anything I find interesting, and sometimes I end up going on the street and just talking to people about science before I actually explain anything.

H: Right, right, you do that thing where you're like, tell me this thing, like, I'm gonna ask you a question that I know you're gonna get wrong and then I'm gonna shame you into learning!

D: Wow, well, that's not really how I look at it, Hank, but that, you know that could be how some people perceive it.

H: Whenever Derek takes his camera out and he asks a question I'm like "oh crap, what am I gonna get wrong now?"

D: And here, I don't even have my camera, we have your cameras.

H: That's true, I did turn that on you once and I said, I said, "How many, how long was it a million seconds ago?"

D: How long was it a million seconds ago, and...

H: And you got it wrong!

D: I got it wrong, big time, there's a factor of ten errors happening in my brain, and uh, yeah.

H: So, if I get something wrong, I will at least have the joy of knowing that I have previously stumped you.

D: You have stumped the Derek.

H: So what's your background?

D: My first degree was in engineering and physics, and my second degree was a PhD in physics education research. How to make films that actually teach science.

H: Right, so you've proven that this technique you use works.

D: I've shown in various research studies- I hesitate to use the word "proven" in any area of science- but the evidence suggests strongly that direct expository teachings, which all of us do from time to time, don't seem to be the most effective for novices, specifically. So for people who don't know anything, telling them stuff doesn't seem to have that big of an impact, and there's I think a variety of reasons for that.

H: Instead, what does work?

D: So what seems to work is actually explicitly bringing up misconceptions and then explaining how they don't quite work and then getting to the truth, which is my goal all the time.

H: Walking down a path, instead of saying "here's how it is".

D: The really important thing is that you start where your audience is, you know, you don't get anywhere if you start at a level where they don't know where you're at but you think that they know where you are.

H: And then walk them through the process of, of how- why is it this is wrong? in fact you probably could figure this out on your own-

D: Just through a series-- it helps to have someone there to guide you through.

H: My favorite of your videos is, "Where Does The Tree Come From", like, where is all that mass of a tree, and people are like, it comes from the water, and the soil, and in fact, if you think about that, why is there no giant hole around the tree, it must come from somewhere else. It comes from- you'll have to watch the video to find out.

D: Yes. You can go to my channel.

H: Go to youtube.com/veritasium. So, are you going to attempt to make me feel foolish, shame me into not--, learning more about my world?

D: Let's try something, let's just try some warm-up questions and see how we go, yeah? So here's the first thing we're gonna try. I'm gonna give you a set of logical statements and you're gonna tell me whether these are true or false, together, whether they fit together.

H: Oh crap, I'm terrible at logic.

D: Are you?

H: Yeah, I like flunked that section of the SAT, like seriously.

D: Okay, well let's...I think that you can do it. I actually don't think it's... anyway, we'll give it a shot. All roses are flowers. Some flowers fade quickly. Therefore, some roses fade quickly.

H: No. That does not make sense to me.

D: It is false. And that's good, because that's a false question. Let's try another one. A bat and a ball together cost a dollar ten. The bat costs a dollar more than the ball. How much does the ball cost?

H: I wanna say a dollar but that's wrong.

D: What's interesting is that if you ask that question of college students, roughly 80% of them will say 10 cents, that the cost of the ball should be 10c, cause, immediately there's a problem there, cause if you think it through, if the ball is 10c and the bat is a dollar more than the ball, then the bat would a $1.10, and then together they would be a $1.20. So you can clearly see that it wouldn't work. But 80% of people will quickly answer the question that way, the correct answer would of course be 5c- it all works out.

H: I almost said 20c. So that would've been going the wrong way.

D: Yeah, but you know, similar idea, it's hard to do math in your head, I think that that's granted, but I mean the thing that's interesting to me is the way that we're drawn to intuitive answers, to quick answers to things that seem like they should make sense and I think you and I more than most people like to think about things a little deeper, like we don't wanna just go with our gut right away because we know that that can get us into trouble sometimes.

H: Mhmm. Right, especially when you have a guy on your talk show trying to stump you, then you know that something's up.

D: I'm not really trying to stump you, I thought you would do well with these questions, I'll try one more.

H: Okay.

D: So, there are lily pads in a pond, and every day they double in area that they take up. On day 48, the whole pond is covered. When did they cover half the pond?

H: On... day... 47.

D: See, beautiful, beautiful, Hank. That is absolutely correct. So this is where I'm saying, an intuitive reasoner would say, day 24, forget the whole doubling thing, like exponential growth is a crazy thing to get your head around.

H: You had to start with a very small lily pad or it was a very large pond to get to 48 days doubling.

D: Yeah, I don't know how that would actually work, it would be crazy to see day 47 to day 48 would look weird. Um, lemme ask you this question. Where do we get energy? As human beings, where do we get our energy from?

H: Like directly or indirectly?

D: Let's not go too far back down the chain, so let's say fairly directly, where are we getting our energy?

H: From our food.

D: From our food. In what way, like, what kind of food will give you energy?

H: Um, fats, proteins, or sugars, for the most part.

D: Right, and, if say we were talking about a sugar, a common sugar that we get energy from would be--?

H: Glucose, would be the most common one. Is that what we have here?

D: That's what I've got for you there, we have a molecule of glucose. Now, I'm a physicist, I have created this, I'm hoping it's right--

H: yeah, it looks- I mean, I don't know the exact structure of glucose, but you've got your alcohol sticking out here, you've got your oxygen in the ring, and then your extra little--

D: Basically checks out. Okay so the question is, where is the energy coming from?

H: The bonds, man.

D: How so? Can you elaborate? Like, that's the point I wanna get to. Like how do we get energy from bonds.

H: Well, we have, um, complicated....metabolic chemistry that we do on these things, so the idea basically is that this is less stable than carbon dioxide and water, which is what we break it down into, so there's an energy differential between this, which was basically created by a plant probably, it may also have been created by an animal, that wanted to store its energy, and to do that, it converted carbon dioxide and water into a much more complicated thing, and, uh, that difference in stability is energy that was pulled out of the sun to create a more complicated and less--- a molecule with more energy stored in its chemical bonds, then we break that down and reverse that process, pretty much literally reverse that process, to remove the energy that that plant stored. Which is how life works. It's pretty awesome.

D: That is awesome. And I think your view of this is really nuanced and it's great and it's a lot better than most people on the street would say. I mean it's this phrase where we say, "the energy stored in chemical bonds", that's the thing that gives me trouble, that's the thing that I'm concerned about. If you see a bond as an energy storing thing, I feel like that's problematic. Because, anytime you form a bond, what happens? If you have two things and they were separate, and you just bonded them together, what would happen to the energy?

H: What would happen to it?

D: Yeah. If you took two things- like, what is this, oxygen and hydrogen, and you stick them together- of course it makes more sense to stick--

H: Yeah, that wouldn't--
(They're talking about how that combination isn't actually a thing that could form)

D: Sure. But we could stick another thing in there! But the point is, when you bond two things together, what happens to the energy of these things?

H: It----it decreases.

D: Right. And what happens to that energy? That was there?

H: It's heat.

D: It can be heat- it's just released, away from this thing. So I guess my point is, that bonds are kind of a signal, not of energy being there, but of energy not being there.

H: Right. Well, of decreased energy.

D: Of decreased energy. So I guess the point I wanna make is, you know, a lot of people think that energy is stored in chemical bonds, when the answer is, it takes energy to break chemical bonds.

H: It does, but it also takes energy to form them sometimes. For example, it takes energy to form something this-- it takes energy to form glucose. Um, if you have -- and it actually takes energy to break up glucose, you just get more energy out than you put in.

D: This is exactly the point. This is-- this is the crux of the matter. I guess, one of my questions is why do you consider the energy as being stored in that molecule and not stored in these molecules? Here I've got some oxygens.

H: Where did those come from?

(laughing)

H: Are you doing magic tricks now?

D: Why is the energy in these bonds and not in these bonds? People think they're getting energy from glucose they don't think I'm getting energy from oxygen.

H: Well because, well there is energy in those bonds, but there's uh, well there is...well, there is...

D: I just feel like it's unfair to say that there's energy in bonds. Uh, like when you form bonds, energy is given off.

H: I guess, I mean, well it's a useful tool for understanding how energy flows, you know from the sun to our pancreas.

D: My concern is this, right, if you think that there really is energy in bonds, then you would imagine something like breaking those bonds open and releases that energy.

H: Right

D: Which is totally false.

H: That is true.

D: This is my point. It's the formation of bonds that releases energy, and it's the breaking of bonds which takes energy, and if you have that clear idea about bonds it allows you to extrapolate to all sorts of situations. Have you seen these videos where people uh grab ice cubes which are covered in salt and they just squeeze them really hard and it's really really painful? Have you seen those videos?

H: No. That's new for me, but I...

D: This is a thing, OK there's tons of people out there doing like the "Salted Ice Cube Challenge".

H: Of course there are.

D: and it makes your hand really cold like the ice cube might start out at 32 Fahrenheit, I'm doing that for you guys, OK, it might start out like that, but then it's gonna get colder. The ice cube gets colder, by putting the salt on it and then squeezing it. Now why is the ice cube getting colder?

H: Because it's...I don't know.

D: You're breaking the bonds between the water molecules.

H: The hydrogen bonds

D: No, well yes. but, yes. Because it's a solid thing, so you're breaking those bonds in the ice. Right? And that takes energy, it's actually lowering the temperature. So your hand could get down to like, I don't know, 20, 15, 10.

H: Right, but I mean if you have a cube of sugar and you light it on fire, energy is being released.

D: Correct. That's because of forming bonds, it's not because of breaking bonds. And again, my point again is also...

H: Because the bonds that are being formed, have less energy than the bonds, that...before.

D: Exactly.

H: OK.

D: Exactly, that's what I love. but the other thing is, like why do you say that the energy's here and not here, because if you didn't have any oxygen, and you tried to light something on fire, it's not gonna work. So the point is the energy is just as much in these oxygen bonds that you're breathing in as it is in there. If you wanna consider energy to be in bonds in some way at all. So I feel like, we just need to change our views of bonds.

H: But I want the energy to be in here.

D: I know you do.

H: Because that's where I get my energy.

D: I know you do. And so there is a way in which we can say that this has energy.

H: How would you say that.

D: Well, I would say that the energy of these bonds is less than the energy in the bonds of products you could create, so therefore there is more energy kind of with reference to that as your final state. So but I guess, a really important point is to think about initial states and final states. Relative to all these atoms being separate, there is less energy here. If you had all those atoms separated, and you put them together, that would give you energy.

H: Mhmm.

D: You seem unconvinced Hank.

H: I...I'm not unconvinced, I just think it is a less useful cognitive tool. I think that it's more correct.

D: OK, but I feel like we, uh, we just get ourselves into trouble when we think in terms of what you're talking about. Because for example, uh, in nuclear fusion, for example, in the sun. What's happening? You know, these two nucleons are coming together, hydrogens, protons are coming together, and they're fusing with each other.

H: Mhmm.

D: So what's happening, to like, how do we get energy there?

H: Well, that's a whole different story.

D: Is it?

H: Now it's nuclear physics.

D: OK, now it's nuclear physics, but the process is very similar. You're bonding things together. Why are they bonding together?

H: You're not bonding things together.

D: Yes you're bonding things together!

H: Well but not with chemical bonds.

D: Not with chemical bonds, but with nuclear bonds. Does it matter?

H: Yeah.

D: No.

H: It's a different, it's a whole different mechanism.

D: It is a whole different mechanism, but the point of energy is the same. Things come together and they bond, when they can go to a lower energy state.

H: Right.

D: And then they are releasing that energy. I mean there's a thing in physics that we talk about, the nuclear binding energy. This is, you know, one of the most rampant misconceptions I see, anywhere in physics. It's about thinking that these nucleons require energy to bind them.

H: Nucleon protons.

D: Protons and neutrons.

H: Yeah.

D: So, so people think that it takes energy to bind neutrons and protons, but it doesn't.

H: It releases energy.

D: It releases energy, so the point is, things are bound not by the energy they have, but by the energy they have lost.

H: Right.

D: Do you see how beautiful that is?

H: That is nice.

D: Things are bound by the energy they have lost, not by the energy they have.

H: And the energy they're losing is the energy we're using.

D: Exactly.

H: That's a good stopping point.

D: It is, isn't it. Let's bring out a skunk!

(laughing)

H: You were right, we got a skunk.

Jessi: Surprise! Here's a skunk.

H: Yeah, I was being, I'm being quiet. I should, don't have to be quiet?

J: No, she's alright.

H: She's super docile.

J: She knows, she knows you're there.

H: OK.

D: This is the closest I've ever been to a skunk, by far.

J: That's probably a good thing.

H: This is actually not the closest I've ever been to a skunk.

J: Really?

D: That's frightening.

H: Yeah, Katherine once found one in one of the wells around a recessed window in a house. She went in there, with a shirt, and rescued it.

J: Wow. Brave.

H: Yeah, very brave, that's my brave wife. So this is Lollipop the skunk! What kind of skunk is Lollipop?

J: She's a striped skunk.

H: Because of the stripes.

J: Yes, and there are different species of skunk, there are spotted skunks and there's hog-nosed skunks as well. So this is a striped skunk and you can see those...she likes that.

H: Oh yeah, that's what my cat does.

D: Do those other species have stripes?

J: They don't. They have spots, or the hog-nosed does I believe, but the spotted one is smaller than this, looks more like a weasel, and it's more splotchy, spotty. And they're smaller too.

H: Is this native to Montana?

J: This is native to Montana, native to North America, and they'll go down south to Central America as well. And uh, she is not full grown. She's about eight months old, and she'll get bigger than this. They can get quite big. I shouldn't say quite big, they can get, you know, their body can get about that big. [arms about 2 feet apart]

H: They're sort of the size of cats.

J: Yeah, similar. Yeah.

H: But they don't look like cats.

J: They look kinda like a miniature badger.

H: Yeah, totally like a miniature badger.

J: And then they have these short little legs so they kinda walk around like a badger too, they almost waddle.

H: And those look like digging claws to me.

J: They are, yeah yeah. So they use those claws not for defense, or offense, they're...well I guess offense. They're gonna dig up worms.

(laughter)

H: Offensive against the worms, but not for attacking other mammals.

J: No, well they'll go after, they're omnivores and they're opportunistic omnivores.. are you gonna go hide? Oh no, she's not hiding.

D: She spotted the food.

J: She's getting after this food here.

D: That was quite clever.

H: Oh yes.

J: So, perfect timing.

H: When Lollipop came out, she was exhausted, uh, and just wanted to sleep, but then the food got opened, and much more active.

J: And that's two great points. She's nocturnal, so she would be sleeping during the day, so that's why she's so tired, and then, these guys are crazy about food. Crazy about food! Like that's all they really care about. They want to eat and eat and eat and it's and they'll eat anything that resembles food.

H: You need those chemical bonds.

J: Exactly.

H: And the energy that is not stored in the bonds.

D: Now speaking of chemical bonds, like skunks are obviously known for smelling disgusting. what is that molecule that you know, they're spraying at you.

J: Oh, you know I am not a chemist.

D: OK, but she's not trying to spray us.

J: She's not trying to spray you, she's not threatened right now, and actually, they don't want to spray, that's the that's kind of a misconception. Skunks don't go around the world every time just spraying things, anything like a twig breaks in the forest and they spray it. You know they're not going around just trying to douse everything in their stank, but um.

D: They will do it from time to time.

J: They will. They will if their life is threatened. If they feel like their life is threatened, but they are going to warn you ahead of time. Alright, we're going to give you a break, from eating for a second and we'll show you off a little bit more. Um, so they're going to do these warning systems before spraying. So one of the first things that they're gonna do, (you should ask Katherine if this happened) first thing that they'll do is they'll stomp their feet. A lot of people aren't very observant about that, so they'll miss the stomping. 

D: Their front feet?

J: Their front feet, and it's kind of funny, they have these little soft pads and it's almost like they're slapping the ground. Slap slap, slap slap. And then the next warning that they'll do is they'll do these little charges. Now they're not charging to be on the offense, they're not gonna come and attack you or anything. They're going to do these charges and their head is almost down, and they're just running at you and they'll hiss while they're doing it. They're trying to say, "get away from me!"

H: I feel like you have a very good defense mechanism, just use it, rather than trying to charge me, and slap the... just turn around and get me out of there, like pepper spray my face.

J: So the reason they wouldn't, there's a reason, is that they have, now this isn't exact science, but it's approximations. They have about six sprays, before they run out of their stink, and then it takes almost a week for them to recharge. So if they're just going around spraying everything in sight, they're gonna run out and they'll have no defenses.

H: Right.

J: So they want to... first warning is their color, warning colors, and their second warning is the stomp, then the hiss and the charge, some will even do a handstand.

H: What?

D: That is awesome, can we get a picture of...?

J: She doesn't do a handstand, we're working on training her, and she's never been scared enough to show off a handstand, but...

D: But I have seen them like put up their, like they turn away from you, and they lift up their tail and stuff.

J: Yeah yeah, They'll lift their tail, and that's even another warning. There's one more thing they have to do. They're not just gonna put their tail up and just spray. Well, if it's quick thinking they might, but if they're really like trying to ward you off, they'll put their tail up and they'll turn around and aim at you. they'll turn their head around, peaking around the corner and aim at you.

H: So they'll be like, "Where's my butt pointing right now?"

J: And they can shoot up to fifteen feet and they're very accurate.

D: Frightening.

H: Wow, I've looked up the chemicals, um, there's actually a webpage on the internet called the history of skunk stink research basically, but um they're thiols, so they're sulphur compounds. They're organic compounds with sulphur groups on them. You know, sulphur bonded to hydrogen is stinky, and there's a lot of them. There's also thioacetates, which are, um, also sulphur compounds.

J: So it's a bunch of different kinds of sulphurs.

H: And alkaloids, there's a ton, there's a ton. There's so many. Uh, the spotted skunk has different ones than the hog-nosed skunk which has different ones from the striped skunk. I'm learning all about this.

J: Here, why don't you go on the table. That's interesting. All those different kinds there. I do know if you are sprayed directly like in the face it will make your eyes burn...

[Skunk falls off table]

D: We just saw a skunk flip right here. I don't know about handstands, but she does a flip pretty well.

H: It's very slippery.

J: I am not supposed to be on a slippery table. I don't climb.

H: This is food, I'm good.

J: I just hang out on the ground and eat food. Sorry Lollipop.

H: Aww, well that...

J: So if you could, what.

H: It didn't even freak her out! She's fine.

J: They're really kinda like bulldozers almost.

H: Skunks are very common, but you don't generally see them.

J: No, they're kinda secretive, so they're going to, you mean, they don't camouflage obviously, they want to stand out, um, but they mind their own business. They just go through the forest and they you know rough and tumble on the under story there and just digging roots and tubers up and eating anything that they come across, so they live a solitary life, and don't really try to get in your business. Unless you have trash around your house.

H: Right.

D: I've seen like groups of skunks going around together, like families.

J: Families, mom and babies.

D: So do they hang out with their families? Or only for a short period of time?

J: About a year maybe. That's gonna be the extent of the time. It's usually gonna be even, you know, [To skunk] push that off of there. It's usually going to be less time than that.

H: Get it. Does not care for glucose.

J: [to skunk] I want protein.

D: Wow, she's voracious.

J: She will eat any- if we give her a bunch of food, she'll eat until she makes herself sick. [to skunk] Nice work. And I brought some little bugs, you can see she really enjoys..

H: Ah, live bugs! Her favorite!

J: Bugs.

D: Okay, it's behind you. Turn around.

J: Do you smell it?

All: Aw, yeah!

H: Crunch, crunch, crunch, crunch, crunch.

D: You can tell she really loves that food.

J: She really enjoys it.

H: So Lollipop, uh, though she doesn't want to spray us, she also couldn't.

J: She is de-scented. And that is, it's a procedure kind of like spaying or neutering, and she feels no pain now from the surgery. We do that because she's an educational animal and it'd be very educational if someone were sprayed.

H: A little too educational.

J: We don't want to go down that path. So that's the reason that we do it. And she was rescued from a fur farm, so she was going to be raised to be someone's scarf or hat or...

H: I didn't even know they did that with skunks.

J: Yeah actually, they're common. Yeah, but she gets to live out her life at Animal Wonders eating as much food--well, not as much as she can eat--but, a lot of it.

D: As much as you allow.

H: As much as you allow.

D: She does seem like she knows you though. You know, like she comes over to you, and she knows where the food's coming from.

J: She knows I have the food.

D: But it seems like more than that. Right? Like even...

J: Yeah. We have a trust bond. And that's what we work for. You see if I try to pick her up she flattens herself? She's like, "no, I don't want to be picked up."

H: Hunh! Hunh!

D: That's amazing.

J: Um, because skunks are not, they're not good climbers or flyers, so they are just really comfortable on the ground. So if I hold her like this she's going to cling on because she wants her feet, you know, stabilized. So we have a trust bond and an understanding of, you know, how I'm going to treat her and how she's going to treat me. And so, you know, with strangers they're going to move or smell or act differently around her than I would and that might make her a little nervous because she's not quite used to it.

H: Lollipop? I'm surprised that we haven't met you here on the show yet. I'm really glad that you got to come in and be adorable and fall off our table and eat lots of delicious food. I hope that we treated you well and that you enjoyed being on the show. Jessi, thanks for coming in, of course. You can go to Jessi's YouTube channel; it's linked in the description. And of course Derek from Veritasium. You should check out his videos, they'll make you smarter. And if you ever run into him on the street, just walk away. Thank you guys for coming on the show. [To audience] And thank you for watching. If you want to keep getting smarter with us here at SciShow, you can go to youtube.com/scishow and subscribe.