WEBVTT - Listener Questions #16 0:00:14.120 --> 0:00:18.120 Snowflakes are hexagons, and each one is unique. Their amazing 0:00:18.160 --> 0:00:20.680 symmetry just adds to their mystique. 0:00:21.079 --> 0:00:24.680 I've heard flamingos are pink because of their diet. What 0:00:24.800 --> 0:00:27.639 if I ate a flamingo? Would I turn pink? 0:00:27.680 --> 0:00:31.480 If I tried it, i'dne injections protect from radiation. I 0:00:31.480 --> 0:00:34.880 saw it on TV, but I don't understand the mechanism. 0:00:34.960 --> 0:00:36.519 How exactly can that be? 0:00:37.440 --> 0:00:40.600 Whatever questions keep you up at night, Daniel and Kelly's 0:00:40.600 --> 0:00:44.240 answers will make it right. Welcome to Daniel and Kelly's 0:00:44.280 --> 0:01:00.960 Extraordinary Universe. Hello. I'm Kelly Winer Smith. I study parasites 0:01:01.000 --> 0:01:03.600 and space and I am so excited about our flamingo 0:01:03.680 --> 0:01:06.160 question today. 0:01:06.560 --> 0:01:09.200 Hi. I'm Daniel. I'm a particle physicist and a professor 0:01:09.200 --> 0:01:11.600 at UC Irvine, and I've never eaten a flamingo. 0:01:12.360 --> 0:01:15.480 I haven't either, as we'll see later in the show, 0:01:15.520 --> 0:01:18.319 we probably ought not to. But so my question for 0:01:18.440 --> 0:01:21.400 you today, Daniel. So we are recording the day before 0:01:21.560 --> 0:01:23.640 Google Calendars tells me that it's your birthday. 0:01:23.720 --> 0:01:24.720 How does Google know that? 0:01:25.160 --> 0:01:29.640 I'm actually not sure. I must have put it in 0:01:29.680 --> 0:01:31.480 at some point in the past, because you know, I've 0:01:31.480 --> 0:01:34.120 been co hosting with you for a while now, But 0:01:34.200 --> 0:01:35.959 so how do you celebrate birthdays? 0:01:36.280 --> 0:01:39.040 So, yeah, I'm turning fifty tomorrow, which is kind of 0:01:39.040 --> 0:01:42.360 a big milestone. But I actually don't really celebrate my birthday. 0:01:42.520 --> 0:01:44.720 I don't feel like it's that special a day, and 0:01:44.720 --> 0:01:47.120 I'm not really that intwo birthdays and sort of like 0:01:47.600 --> 0:01:50.240 being on the spot that way. I sort of prefer 0:01:50.280 --> 0:01:52.680 to fade into the background. And so to counteract that, 0:01:52.680 --> 0:01:54.960 I've actually been rounding up my age to fifty for 0:01:55.040 --> 0:01:57.680 a few years now, are you serious, which Katina is 0:01:57.720 --> 0:02:00.320 not very excited about. Yeah, especially because when she turned 0:02:00.360 --> 0:02:02.880 forty six, I welcomed her into the round up to 0:02:02.880 --> 0:02:06.400 fifty club and she was like, no, thank you. 0:02:05.680 --> 0:02:10.120 You can stay there alone. Daniel. Wow, I'll have to 0:02:10.160 --> 0:02:13.000 remember that strategy. I also may fade into the background 0:02:13.040 --> 0:02:17.399 birthday person, but I hadn't thought about the rounding up strategy. 0:02:17.400 --> 0:02:21.000 And I think I'm so I always forget how old 0:02:21.040 --> 0:02:26.600 I am. But I'm forty three, okay, is that right? No, 0:02:26.639 --> 0:02:28.600 my birthday's in October and it's twenty twenty. I'll be 0:02:28.720 --> 0:02:31.720 forty three in October, so I'm forty two. So it's 0:02:31.760 --> 0:02:33.440 not quite time for me to round up yet, but 0:02:33.560 --> 0:02:34.880 I will. I'll get there soon. 0:02:35.000 --> 0:02:37.120 Well, Katrina tells me it's ridiculous to round up, but 0:02:37.200 --> 0:02:39.200 I say, hey, look, it's arbitrary to round up to 0:02:39.280 --> 0:02:42.240 the year. People aren't super precise about how old they are. 0:02:42.240 --> 0:02:44.560 When you ask them. They don't say I'm forty two 0:02:44.639 --> 0:02:47.200 years and seven months and three days. They round up 0:02:47.240 --> 0:02:49.200 to the year, right, So I think, hey, I just 0:02:49.320 --> 0:02:51.320 round up to the decade. You know, what's the big deal? 0:02:51.639 --> 0:02:54.400 Sure, yeah, No, Physicists are always you know, making broad 0:02:54.400 --> 0:02:57.679 assumptions about things and rounding, and so you might as well. 0:02:58.600 --> 0:03:01.000 Yeah, Pie is three and Daniel's fifty, what's the big deal? 0:03:01.080 --> 0:03:02.880 That's right there? You go, Well, I hope you have 0:03:02.960 --> 0:03:06.680 an amazing decade. Arbitrary though that milestone may be to you. 0:03:08.919 --> 0:03:11.320 All right, Well, we're not here to talk about Daniel's birthday. 0:03:11.320 --> 0:03:13.880 We're here to answer your questions about the nature of 0:03:13.919 --> 0:03:15.760 the universe. How does it all work, how does it 0:03:15.760 --> 0:03:18.639 fit together? How can we make it click together in 0:03:18.720 --> 0:03:21.640 your mind? And so, as usual, we invite people to 0:03:21.800 --> 0:03:24.400 send us their questions right to us to questions at 0:03:24.560 --> 0:03:28.079 Danielankelly dot org. We write back to everybody with a response, 0:03:28.120 --> 0:03:29.880 we either give you the answer, or make a joke, 0:03:29.960 --> 0:03:31.600 or say we don't know, here's something to read. 0:03:32.520 --> 0:03:35.360 That's right. Lately, often I've been giving a reading suggestions, 0:03:35.480 --> 0:03:38.440 or if we don't know, we say we'll find out. 0:03:38.600 --> 0:03:42.200 And sometimes it becomes a question on a listener Questions episode. 0:03:42.320 --> 0:03:44.560 And today we have a lot of examples of that. 0:03:44.560 --> 0:03:46.880 That's right, So let's jump right in. Our first question 0:03:47.000 --> 0:03:50.640 comes from Zach in Minnesota. Zach is a question about 0:03:50.720 --> 0:03:52.960 why snowflakes are all different. 0:03:53.320 --> 0:03:57.280 Hey, they're extraordinaries. It's winter here in Minnesota and we 0:03:57.440 --> 0:04:00.240 just got a ton of snow. My dad took a 0:04:00.320 --> 0:04:04.680 really great picture of a beautifully symmetrical snowflake. I understand 0:04:04.800 --> 0:04:08.640 why snowflakes tend to form hexagonally. I think because of 0:04:08.680 --> 0:04:13.400 the crystallization pattern of water. But I don't understand why 0:04:13.920 --> 0:04:17.720 snowflakes so often come out looking so perfectly symmetrical. Why 0:04:17.800 --> 0:04:21.800 should they form exactly the same intricate crystallization on one 0:04:21.960 --> 0:04:24.640 arm as opposed to the other arm. I know this 0:04:24.720 --> 0:04:28.279 isn't a universal thing. Some snowflakes aren't symmetrical, but so 0:04:28.360 --> 0:04:32.440 many are. It just seems unlikely. Is this just because 0:04:32.480 --> 0:04:36.200 there are so many snowflakes or is there something deeper 0:04:36.240 --> 0:04:38.960 going on? Look forward to hearing your thoughts. 0:04:39.000 --> 0:04:41.120 Now, Daniel. If you and I were really good at this, 0:04:41.160 --> 0:04:43.919 we would have saved this for a Christmas episode, but 0:04:44.000 --> 0:04:45.640 instead we're going to release it in the middle of 0:04:45.640 --> 0:04:46.160 the summer. 0:04:46.560 --> 0:04:49.200 That's when people want snow, right, That's when they're missing it. 0:04:49.600 --> 0:04:51.320 You know, in the middle of winter people are like, Ugh, 0:04:51.400 --> 0:04:53.400 don't talk to me about snow. I'm fed up with it. 0:04:54.160 --> 0:04:55.760 Well, I guess it depends on where you are on 0:04:55.800 --> 0:04:58.560 this planet. Right it's winter somewhere. So okay, this is 0:04:58.560 --> 0:05:00.719 going to be a really good episode for the Australians 0:05:00.760 --> 0:05:02.040 if they're into snow. 0:05:03.520 --> 0:05:06.520 Or if you're sweltering in Texas this summer. Listen to 0:05:06.640 --> 0:05:08.800 this frosty episode about snowflakes. 0:05:09.120 --> 0:05:12.159 Amazing. All right, So, Daniel, I have to admit that 0:05:12.320 --> 0:05:17.080 I don't know why each snowflake has a unique shape. 0:05:17.680 --> 0:05:21.360 Can we start there before we get to why they're symmetrical? 0:05:21.640 --> 0:05:23.560 Yeah? I think that is the right direction to start from. 0:05:23.600 --> 0:05:25.560 This is a really cool question because I think Zach 0:05:26.080 --> 0:05:29.039 is thinking about how the snowflakes form, and he's wondering like, 0:05:29.320 --> 0:05:31.920 how can one arm form the same pattern as the 0:05:32.000 --> 0:05:34.400 arm on the other side. Is there some global for 0:05:34.520 --> 0:05:36.880 us controlling it? And so you're right, we need to 0:05:36.880 --> 0:05:40.680 think about the symmetry and the diversity of these objects. 0:05:40.839 --> 0:05:44.360 And snowflakes are really fascinating. And as it turns out, 0:05:44.400 --> 0:05:47.400 the cutting edge of human understanding of snowflakes doesn't have 0:05:47.480 --> 0:05:51.680 a complete answer to this question. Snowflakes remain mysterious. Yes, 0:05:51.720 --> 0:05:52.920 that's right, fascinating. 0:05:53.000 --> 0:05:54.839 There's not enough money in snowflakes, man. 0:05:57.080 --> 0:05:59.440 But if you go out into a snowstorm and you 0:05:59.480 --> 0:06:01.359 put out your hand and you see snowflakes land on 0:06:01.360 --> 0:06:03.440 your palm, and you can look at them briefly, just 0:06:03.480 --> 0:06:05.480 before they melt, and you notice they are not all 0:06:05.520 --> 0:06:08.800 the same. There's an enormous variety of snowflakes form this 0:06:08.839 --> 0:06:11.640 pattern and that pattern and the other pattern. And you know, 0:06:11.640 --> 0:06:13.800 people have known this for a long long time. This 0:06:14.000 --> 0:06:16.719 is famous quote from Thereaux who says, how full of 0:06:16.760 --> 0:06:20.200 the creative genius is the air in which these are generated? 0:06:20.600 --> 0:06:23.520 Beautiful? But the answer is science science. 0:06:24.000 --> 0:06:26.160 But you know he was presient about this even though 0:06:26.160 --> 0:06:28.840 he didn't understand it. The answer is something about the 0:06:28.920 --> 0:06:30.719 chemistry of air, which we'll get to. 0:06:31.080 --> 0:06:32.440 I mean, you said a word I don't like, but 0:06:32.760 --> 0:06:34.279 let's let's move on anywhere. 0:06:36.360 --> 0:06:38.520 So your question was about the symmetry, so let's start 0:06:38.520 --> 0:06:41.719 with that, like why do snowflakes form this white, weird 0:06:41.839 --> 0:06:44.840 six prong pattern anyway, And that does come down to 0:06:44.960 --> 0:06:48.960 chemistry how the water molecules themselves bond to form the 0:06:49.000 --> 0:06:51.800 nexus of the crystal at the core. But let's back 0:06:51.880 --> 0:06:54.720 up and start with like, how does snow form, where 0:06:54.760 --> 0:06:58.520 does it come from? It comes from water freezing in clouds. 0:06:59.040 --> 0:07:01.520 And the things I understand about water is we're all 0:07:01.520 --> 0:07:04.359 familiar with ice and then liquid water and of course 0:07:04.480 --> 0:07:09.320 water vapor, steam, right, But water has complicated chemistry depending 0:07:09.360 --> 0:07:11.559 on the pressure. So down to the surface and normal 0:07:11.600 --> 0:07:14.920 atmosphere pressure, water has those three phases. But if you 0:07:15.000 --> 0:07:17.400 go up into the upper atmosphere or out into space, 0:07:17.440 --> 0:07:20.000 for example, where pressure is very very low, there is 0:07:20.080 --> 0:07:23.600 no liquid water. There's only solid in gas. And so 0:07:23.720 --> 0:07:25.800 if you have solid water and you heat it up, 0:07:25.960 --> 0:07:28.720 you don't get liquid water. Out in space, you get vapor. 0:07:28.840 --> 0:07:32.080 It goes directly from solid to gas. So there aren't 0:07:32.120 --> 0:07:35.360 three phases everywhere you can look up this phase diagram 0:07:35.360 --> 0:07:37.680 of water to learn more and that's going to turn 0:07:37.720 --> 0:07:40.280 out to be key. So what happens is you have 0:07:40.320 --> 0:07:43.080 the atmosphere and there's warm moist air that gets pushed 0:07:43.160 --> 0:07:45.840 upward when it hits the front, and that water condenses 0:07:45.960 --> 0:07:48.560 into droplets. So the air is also filled with like 0:07:48.640 --> 0:07:51.280 tiny dust particles, and each of those like can nucleate 0:07:51.360 --> 0:07:53.920 a tiny little droplet, and that's what a cloud is. 0:07:54.280 --> 0:07:57.200 Cloud is all these water droplets that have been nucleated 0:07:57.240 --> 0:07:59.920 as warm moist air has gone up and the water 0:08:00.040 --> 0:08:01.680 sort of comes out of the solution. 0:08:01.440 --> 0:08:05.040 Of the air and nucleated just means it's like surrounding 0:08:05.040 --> 0:08:05.800 the piece to dust. 0:08:05.960 --> 0:08:08.000 Mm hmm okay, yeah. Like you might ask why do 0:08:08.040 --> 0:08:10.400 you get a water droplet here and not one centimeter 0:08:10.560 --> 0:08:13.280 or one micron over? Like why do they form where 0:08:13.320 --> 0:08:16.040 they form and not somewhere else? The answer is dust. 0:08:16.080 --> 0:08:18.600 It's sort of like the way in the early universe 0:08:18.920 --> 0:08:22.440 we had like slight over densities in the plasma and 0:08:22.480 --> 0:08:25.360 that's what gravity grabbed onto to nucleate the formation of 0:08:25.400 --> 0:08:27.720 what turned into galaxies and stuff, Like why did galaxies 0:08:27.760 --> 0:08:29.920 form here and there? There has to be a reason 0:08:29.960 --> 0:08:32.360 it starts, and in the case of water droplets, it's 0:08:32.400 --> 0:08:33.720 tiny particles of dust. 0:08:33.960 --> 0:08:37.920 I heard it was also tiny bacteria that are in 0:08:37.960 --> 0:08:40.720 the atmosphere, Is that true? Or their bacteria around there 0:08:40.760 --> 0:08:41.720 forming snowflakes. 0:08:42.040 --> 0:08:44.480 There are bacteria out there. And dust is a very 0:08:44.520 --> 0:08:47.760 broad term. It includes lots of tiny stuff, you know, 0:08:47.800 --> 0:08:49.600 the way like sand does. And if you zoom in 0:08:49.640 --> 0:08:53.240 on this amazing variety of stuff in the atmosphere, we 0:08:53.320 --> 0:08:54.720 just call it dust. We can have a whole another 0:08:54.760 --> 0:08:56.440 episode about it, like what is dust? 0:08:56.720 --> 0:08:58.200 Sure that sounds fascinating. 0:09:00.000 --> 0:09:02.040 Anyway, you put all these together, you have a cloud. 0:09:02.080 --> 0:09:04.960 A cloud is like a million tons of water hanging 0:09:05.040 --> 0:09:08.480 there in the air, sort of amazing. So now temperatures 0:09:08.559 --> 0:09:11.200 drop right, and some of those droplets freeze, some of 0:09:11.240 --> 0:09:14.400 them evaporate become a vapor, but some of them freeze 0:09:14.480 --> 0:09:16.760 and you get a little crystal. And so here's where 0:09:16.760 --> 0:09:19.520 the chemistry comes in. You have this water molecule, which 0:09:19.559 --> 0:09:22.360 is like an oxygen and two hydrogens, and the two 0:09:22.440 --> 0:09:25.120 hydrogens come off at an angle, right, It's not like 0:09:25.280 --> 0:09:28.400 a line where you have hydrogen oxygen hydrogen. If you 0:09:28.400 --> 0:09:30.360 seem like a little drawing of water molecule you know, 0:09:30.360 --> 0:09:32.959 the hydrogen, it's like pulled close together. The angle between 0:09:32.960 --> 0:09:35.000 them is like one hundred and four degrees or something, 0:09:35.280 --> 0:09:37.680 and so when these things come together to make a crystal, 0:09:38.080 --> 0:09:40.839 they click together sort of like lego bricks. Right, there's 0:09:40.920 --> 0:09:44.160 bonds between them, and that makes a little hexagon. So 0:09:44.200 --> 0:09:46.719 you link up six water molecules. The oxygens are like 0:09:46.800 --> 0:09:50.160 the vertices on a hexagon, and then the bond between 0:09:50.160 --> 0:09:52.640 the oxygen and one hydrogen is like the edge of 0:09:52.679 --> 0:09:55.600 that hexagon, and then there are six hydrogen molecules sort 0:09:55.600 --> 0:09:58.800 of sticking out. But it makes this ring, this hexagonal ring, 0:09:59.360 --> 0:10:01.640 and then you just keep adding water molecules and it 0:10:01.679 --> 0:10:03.320 builds out and out and out, and you get a 0:10:03.320 --> 0:10:04.320 hexagonal crystal. 0:10:04.480 --> 0:10:07.160 Okay, so why do you get six in the center? 0:10:07.240 --> 0:10:09.880 Is that just available binding sites? 0:10:10.360 --> 0:10:10.560 Yeah? 0:10:10.600 --> 0:10:12.439 I think it's because chemistry. 0:10:12.480 --> 0:10:17.439 Man, you get six because the angles. So imagine your 0:10:17.440 --> 0:10:20.200 oxygen atom and has two hydrogens coming off and there's 0:10:20.200 --> 0:10:22.720 one hundred degrees between them, which means is like two 0:10:22.840 --> 0:10:25.920 hundred and sixty degrees on the other side, right, So 0:10:26.040 --> 0:10:28.960 the other water molecule comes in with its hydrogen. It 0:10:29.000 --> 0:10:31.720 comes around the back on that big open space and 0:10:31.760 --> 0:10:35.080 it splits that in half, and that's what determines the angle. 0:10:35.320 --> 0:10:37.800 So half of two sixty you get about one hundred 0:10:37.800 --> 0:10:39.800 and thirty and that's the angle there that you build 0:10:39.880 --> 0:10:41.000 up to make the hexagons. 0:10:41.120 --> 0:10:43.640 Got it? Okay? I remember in organic chemistry there's a 0:10:43.679 --> 0:10:46.760 reaction called a backside attack, and the biologists in that 0:10:46.840 --> 0:10:49.720 class we could not get over that anyway. 0:10:49.720 --> 0:10:52.480 All right, moving on, all right, So initially you have 0:10:52.559 --> 0:10:55.719 this tiny, tiny crystal. It's like microns wide. And by 0:10:55.760 --> 0:10:58.080 the way, if you are out chopping and you see 0:10:58.080 --> 0:11:01.920 something called hexagonal water, that's a scam. It's not better 0:11:01.960 --> 0:11:05.560 for you. It's just pseudoscience, supplemental nonsense. 0:11:05.600 --> 0:11:07.160 I've never heard of that. What do they claim me? 0:11:08.040 --> 0:11:10.520 I don't know. I don't even want to give them 0:11:10.520 --> 0:11:11.160 more airtime. 0:11:11.360 --> 0:11:13.600 Okay, save your money people, exactly. 0:11:14.360 --> 0:11:16.000 All right. So what we're talking about so far is 0:11:16.040 --> 0:11:19.280 just the core of the snowflake, right, it's this hexagonal crystal, 0:11:19.600 --> 0:11:22.840 and that can require like a million of these droplets. Wow, 0:11:22.960 --> 0:11:25.520 you have a tiny number of snowflakes compared to the 0:11:25.600 --> 0:11:27.760 number of droplets. It really takes a lot of droplets 0:11:27.760 --> 0:11:28.720 to make one snowflake. 0:11:28.760 --> 0:11:31.440 So why doesn't the snowflake just become infinite. Why did 0:11:31.440 --> 0:11:34.560 at some point does it stop accumulating more waters. 0:11:34.360 --> 0:11:36.679 Well, it has limited time in the cloud. So what 0:11:36.720 --> 0:11:39.480 happens next is you have this seated crystal which blows 0:11:39.520 --> 0:11:43.320 around inside the cloud, accumulating more and more, and then 0:11:43.360 --> 0:11:45.840 eventually it gets so heavy that it drops, right, And 0:11:45.840 --> 0:11:48.199 so it's a limited time in the cloud. Otherwise it 0:11:48.200 --> 0:11:52.520 would form like a cloud sized crystal, which should be awesome, 0:11:52.840 --> 0:11:55.120 and maybe that happens on some alien planet, but then. 0:11:55.000 --> 0:11:57.439 It falls on your head and that would be too much. 0:11:57.640 --> 0:12:00.240 So we're set up now to answer Zach's question. Right, 0:12:00.320 --> 0:12:02.400 we start with his crystal, and we understand why it's 0:12:02.440 --> 0:12:06.760 a hexagon, But then why does it form six identical arms, 0:12:06.800 --> 0:12:08.679 each of which are the same on one crystal, but 0:12:08.760 --> 0:12:11.559 different from all the other crystals? Right? And when I 0:12:11.600 --> 0:12:14.240 was first reading about this, my hypothesis was maybe it's 0:12:14.280 --> 0:12:17.640 some like impurity in the crystal, where like something has 0:12:17.679 --> 0:12:21.760 happened at the core, which then determines how it grows outwards. Right, 0:12:21.760 --> 0:12:25.120 you need something coordinating across the arms. But it turns 0:12:25.120 --> 0:12:27.719 out it's not that at all. And we know that 0:12:27.800 --> 0:12:32.760 because of amazing experiments done by a physicist Ukichiro Nakaya 0:12:32.840 --> 0:12:35.280 in Hokkaido in Japan in the nineteen thirties. He was 0:12:35.360 --> 0:12:38.360 really curious about snowflakes. He just like went for walks 0:12:38.360 --> 0:12:40.520 and saw snowflakes, and he asked the same question, but 0:12:40.559 --> 0:12:42.760 he wanted to figure it out. He did all these experiments, 0:12:42.840 --> 0:12:45.480 so he replicated the conditions of a cloud in the lab, 0:12:46.000 --> 0:12:48.600 and what he saw was that the formation of the 0:12:48.640 --> 0:12:52.440 crystal beyond the initial seed depends extremely sensitively on the 0:12:52.480 --> 0:12:56.880 temperature and on the density of water vapor. So, for example, 0:12:57.120 --> 0:12:59.679 you can get these like weird long needles that form, 0:13:00.080 --> 0:13:02.440 and you crank up the temperature a little bit and 0:13:02.480 --> 0:13:05.280 you get thin plates, or you get dendrites, or you 0:13:05.320 --> 0:13:08.000 get another formation. You crank it up another little bit 0:13:08.040 --> 0:13:10.480 and you get back to needles or back to columns. 0:13:10.880 --> 0:13:14.240 And so there's a lot of really complicated like chemistry 0:13:14.280 --> 0:13:17.280 and solid sat phistics that's happening there where these crystals 0:13:17.280 --> 0:13:21.000 are forming in certain patterns. Again super duper sensitive to 0:13:21.120 --> 0:13:22.760 the density and the temperature. 0:13:23.080 --> 0:13:25.800 Okay, I'm following you there, but I still feel like 0:13:25.800 --> 0:13:28.079 there's a jump to make, yes to hit symmetry. 0:13:28.240 --> 0:13:30.920 So now start with you or quarter crystal, right, the 0:13:31.040 --> 0:13:33.400 quarter crystal, some hexagon. Now it's going to blow through 0:13:33.440 --> 0:13:36.800 the cloud. The cloud is not uniform in density and temperature. 0:13:36.880 --> 0:13:38.680 There are regions of higher density, there are regions of 0:13:38.679 --> 0:13:41.720 lower density. There are colder and moral regions. As that 0:13:41.840 --> 0:13:46.120 snowflake blows through the cloud, its crystals grow depending on 0:13:46.200 --> 0:13:49.679 the density and temperature it's experiencing moment to moment. So 0:13:49.760 --> 0:13:51.679 like right now it grows in this certain pattern. Ooh, 0:13:51.679 --> 0:13:53.959 then the density drops and now it's going to make needles. Oh, 0:13:54.040 --> 0:13:55.719 now the density goes up. Ooh, now it's back to 0:13:55.760 --> 0:13:59.120 making these flat things. And so that's what controls the 0:13:59.160 --> 0:14:02.000 growth of each of the arms. And because all of 0:14:02.040 --> 0:14:05.920 the arms experience the same unique path through the cloud, 0:14:05.920 --> 0:14:09.640 which gives it a unique temperature and density history, that's 0:14:09.679 --> 0:14:13.600 why every snowflake is different. If two snowflakes had exactly 0:14:13.640 --> 0:14:16.319 the same trajectory through the cloud, you would expect them 0:14:16.360 --> 0:14:18.760 to be exactly the same. And that's probably true, but 0:14:18.840 --> 0:14:22.440 impossible to test, right, So we think the variety of 0:14:22.560 --> 0:14:26.920 snowflakes comes from their individual experience through the temperature and 0:14:26.960 --> 0:14:31.320 density fluctuations in the cloud which control their growth. And 0:14:31.360 --> 0:14:34.560 that also explains why they're the same on individual snowflake 0:14:34.560 --> 0:14:37.160 because on an individual snowflake, all the arms have the 0:14:37.200 --> 0:14:40.880 same experience, the same history through the density and the temperature. 0:14:41.080 --> 0:14:44.280 So it's really kind of an awesome like probe through 0:14:44.320 --> 0:14:44.760 the cloud. 0:14:45.040 --> 0:14:49.000 That's amazing, yeah, and beautiful and I'm trying to pull 0:14:49.000 --> 0:14:51.480 together like the Hallmark version, like we're all a result 0:14:51.560 --> 0:14:55.119 of the unique paths that we take. Anyway, very cool. 0:14:54.880 --> 0:14:56.760 It's very cool, and it's sort of amazing and lucky, 0:14:56.800 --> 0:15:00.440 and it's another example of how amazing complexity emerges in world. 0:15:00.480 --> 0:15:02.760 You know, this could have been totally boring. It could 0:15:02.760 --> 0:15:05.320 have been that snowflakes all just form hexagons and then 0:15:05.400 --> 0:15:07.920 drop and they're all the same, and like, yeah, hexagons 0:15:07.920 --> 0:15:11.160 are cool. But because they're so sensitive to density and temperature, 0:15:11.160 --> 0:15:15.160 we get this incredible variety of beautiful forms. It amazes me. 0:15:15.240 --> 0:15:17.520 It makes me wonder about that same philosophical question we've 0:15:17.520 --> 0:15:20.320 talked about before, like why do we think that this 0:15:20.400 --> 0:15:22.520 kind of stuff is beautiful? Are we programmed to do 0:15:22.560 --> 0:15:24.920 it somehow? Is it because we evolved on this planet 0:15:25.440 --> 0:15:27.760 or is it just something deep about being alive and 0:15:27.800 --> 0:15:31.040 aware in the universe? Like do aliens find their ugly 0:15:31.080 --> 0:15:31.840 planet beautiful. 0:15:31.880 --> 0:15:36.000 Also well, it is now the peak heat and humid 0:15:36.040 --> 0:15:38.760 period in Virginia, so I am looking forward to seeing 0:15:38.800 --> 0:15:42.160 the snow. As you said, let's see if Zach feels 0:15:42.240 --> 0:15:44.120 satisfied with this unique answer. 0:15:44.400 --> 0:15:47.080 Hi, Daniel and Kelly, thank you for the beautiful answer 0:15:47.160 --> 0:15:50.280 to my question about these beautiful crystals, especially since it 0:15:50.360 --> 0:15:52.720 meant wading into a bit of chemistry to do so. 0:15:53.440 --> 0:15:55.720 I too was surprised that the crystal shape was not 0:15:55.960 --> 0:15:59.400 intrinsic to the nucleation dust, but rather a kind of 0:15:59.600 --> 0:16:03.160 record of the snowflake experience as it drifts through its cloud. 0:16:03.960 --> 0:16:06.520 It makes me wonder if there are other polar molecules 0:16:06.520 --> 0:16:09.920 that could form snowflakes with other basic patterns instead of hexagons, 0:16:10.040 --> 0:16:12.920 like squares or triangles, or if there would be some 0:16:13.080 --> 0:16:15.640 molecules that would tend to make three D structures instead 0:16:15.640 --> 0:16:19.280 of planer ones. Anyhow, on a personal note, my son 0:16:19.480 --> 0:16:21.920 was born just a week ago, and you have me 0:16:22.000 --> 0:16:25.200 smiling thinking about how he's going to gather experiences as 0:16:25.200 --> 0:16:27.920 he grows to become something unique and beautiful as well. 0:16:28.360 --> 0:16:29.160 Thanks again, guys. 0:16:50.120 --> 0:16:52.720 All Right, Daniel, this is quite possibly the most important 0:16:52.760 --> 0:16:54.360 question we've ever answered on the show. 0:16:56.000 --> 0:16:58.320 Solunny because it determines what you're gonna have for your 0:16:58.360 --> 0:16:59.200 birthday dinner. 0:16:59.240 --> 0:17:02.520 Maybe maybe, and also his biology, so that automatically puts 0:17:02.520 --> 0:17:06.280 it in the top fifty percent. But let's enjoy this 0:17:06.359 --> 0:17:08.760 amazing question from Bernard and Munich. 0:17:09.280 --> 0:17:12.120 Hi, Danielle and Kelly. This is Bernhardt from Munich in Germany. 0:17:12.680 --> 0:17:15.680 I understand that flamingos are pink because of their diet, 0:17:16.200 --> 0:17:18.679 but it's the pink color just in their feathers or 0:17:18.680 --> 0:17:21.720 also in their flesh. And could I become pink if 0:17:21.760 --> 0:17:25.720 I would start eating flamingos instead of my usual vegetarian food. 0:17:26.160 --> 0:17:28.720 Love your show by incredible. 0:17:30.560 --> 0:17:34.840 How seriously do you think Bernard is considering abandoning his vegetarianism. 0:17:35.040 --> 0:17:36.760 Do we have a weighty responsibility here? 0:17:36.920 --> 0:17:40.720 You know? So I was reading about the frequency at 0:17:40.760 --> 0:17:44.320 which people drop vegetarianism, and it is pretty high. I 0:17:44.359 --> 0:17:46.879 think it's something like sixty to seventy five percent of 0:17:46.880 --> 0:17:50.679 the people who become vegetarians will not stay vegetarians. But 0:17:50.760 --> 0:17:54.760 I really doubt that he's going to drop his vegetarianism 0:17:54.920 --> 0:17:59.200 for flamingos, and not least of all because it would 0:17:59.200 --> 0:18:00.480 be very hard for him to get his hands on 0:18:00.520 --> 0:18:01.080 a flamingo. 0:18:01.960 --> 0:18:04.200 Well, your husband is a dedicated vegetarian, isn't he. 0:18:04.200 --> 0:18:06.760 He is, Yeah, he's been a vegetarian for twenty years. 0:18:06.800 --> 0:18:08.560 And I think the worst thing that I have done 0:18:08.560 --> 0:18:11.399 to him during our relationship is I once left a 0:18:11.400 --> 0:18:14.399 few pounds of ur ducan in his fringe when we 0:18:14.400 --> 0:18:16.399 were dating, and I forgot it was there, and so 0:18:16.480 --> 0:18:20.000 he found what is it a turkey inside of a 0:18:20.119 --> 0:18:21.679 duck inside of a chicken. 0:18:22.160 --> 0:18:24.200 I think you have that backwards, but say, yeah. 0:18:24.040 --> 0:18:28.000 Sorry, chicken, it's that you are right anyway, in his refrigerator, 0:18:28.320 --> 0:18:31.520 and he was pretty grossed out anyway, Sorry, honey. 0:18:31.200 --> 0:18:33.400 Good thing there wasn't a flamingo in there as well. 0:18:33.080 --> 0:18:35.479 That's right, that's right. We did look up. Somebody had 0:18:35.520 --> 0:18:37.720 managed to get like twenty four creatures inside of each 0:18:37.720 --> 0:18:38.760 other and that was the max. 0:18:38.840 --> 0:18:42.240 But all right, well, let's get an answer to Bernard's question. 0:18:42.280 --> 0:18:45.680 Tell us, okay, from the beginning, why are flamingos pink? Anyway? 0:18:45.920 --> 0:18:48.440 Right? All right? So there are actually six different species 0:18:48.440 --> 0:18:51.560 of flamingos, and they are all rose colored. They get 0:18:51.600 --> 0:18:54.800 their color through their diets, and so they eat algae. 0:18:54.880 --> 0:18:58.919 They eat crustaceans, and these organisms make their own colors 0:18:58.960 --> 0:19:03.480 called krotenoioids, so they have pigments, but they aren't necessarily pink. 0:19:03.920 --> 0:19:08.800 So some organisms have ways of metabolizing carotenoids to get 0:19:08.800 --> 0:19:10.879 them to be particular colors. And so the way that 0:19:10.920 --> 0:19:14.280 the flamingos metabolize the carotenoids that they get from their 0:19:14.280 --> 0:19:15.840 food turns them pink. 0:19:16.040 --> 0:19:19.560 So metabolized means does chemistry on them, does chemistry and 0:19:19.640 --> 0:19:22.600 basically changes their color. So the things they eat are 0:19:22.640 --> 0:19:25.639 not pink, but they eat this stuff and the stuff 0:19:25.680 --> 0:19:28.119 has something in it and they do chemistry inside and 0:19:28.160 --> 0:19:29.640 that makes them pink. Is that right? 0:19:29.680 --> 0:19:31.760 That's right? Yep. So they're filter feeders and so they're 0:19:31.800 --> 0:19:35.040 eating lots and lots of tiny little things with carotenoids 0:19:35.040 --> 0:19:35.840 that they turn pink. 0:19:36.080 --> 0:19:38.120 And is it good for the flamingos to be pink? 0:19:38.160 --> 0:19:39.920 Do they care? Is it helpful in some way? Or 0:19:40.000 --> 0:19:42.280 are just like a weird oddity in our universe. 0:19:42.560 --> 0:19:45.120 There's some debates over why they're pink, but it does 0:19:45.160 --> 0:19:48.600 seem that being pink is an indicator of how healthy 0:19:48.600 --> 0:19:51.399 you are, so because they get the pink from their diet, 0:19:51.880 --> 0:19:54.879 If you are super extra pink. That is a great 0:19:54.920 --> 0:19:56.600 way of showing people. 0:19:56.800 --> 0:20:00.399