WEBVTT 00:00:00.000 --> 00:00:02.020 Look at your hands for a second. Like, really, 00:00:02.220 --> 00:00:04.519 look at them. Yeah, just hold them up. Feel the 00:00:04.519 --> 00:00:08.699 skin. Think about the muscles working underneath. 00:00:09.099 --> 00:00:11.580 The incredibly complex DNA coiled up tightly 00:00:11.580 --> 00:00:14.480 inside every single cell making up those fingers. 00:00:14.539 --> 00:00:16.699 And you feel solid, right? Yeah, you feel self 00:00:16.699 --> 00:00:19.559 -contained. But the truth is, the very building 00:00:19.559 --> 00:00:22.019 blocks making up those hands, your DNA, your 00:00:22.019 --> 00:00:25.019 proteins, they're the result of an invisible 00:00:25.019 --> 00:00:29.070 microscopic war. A very old war. Exactly. One 00:00:29.070 --> 00:00:31.929 that has been raging across the planet for, well, 00:00:32.310 --> 00:00:34.070 billions of years. And it's a biological war 00:00:34.070 --> 00:00:37.210 over a gas that is, somewhat ironically, literally 00:00:37.210 --> 00:00:39.390 floating right in front of your face as you breathe. 00:00:39.469 --> 00:00:42.289 Right. And to figure out how that war was won, 00:00:42.609 --> 00:00:45.109 we are doing a deep dive today into a comprehensive 00:00:45.109 --> 00:00:48.130 Wikipedia article on nitrogen fixation. It's 00:00:48.130 --> 00:00:50.810 a fascinating topic. It really is. Our mission 00:00:50.810 --> 00:00:53.310 for this deep dive is to track how an incredibly 00:00:53.310 --> 00:00:55.929 stubborn, invisible molecule floating in the 00:00:55.929 --> 00:00:58.710 air gets transformed into the literal foundation 00:00:58.710 --> 00:01:01.130 of your existence. The stuff that makes you... 00:01:01.130 --> 00:01:04.230 Yeah. We're going to explore how nature struggled 00:01:04.230 --> 00:01:08.170 for eons to pull this off, and how a human engineered 00:01:08.170 --> 00:01:13.230 shortcut to bypass nature's limits completely 00:01:13.230 --> 00:01:15.650 exploded the global population. It is arguably 00:01:15.650 --> 00:01:17.750 the most important chemical process on earth, 00:01:17.810 --> 00:01:20.250 and yet it happens almost entirely out of sight. 00:01:20.489 --> 00:01:22.730 Right, because when we think of things we need 00:01:22.730 --> 00:01:25.510 to survive from the air, we automatically think 00:01:25.510 --> 00:01:28.430 of oxygen. Oh, always, oxygen gets all the glory. 00:01:28.930 --> 00:01:31.689 Exactly. But nitrogen is this hidden architect. 00:01:31.890 --> 00:01:34.569 We absolutely need it to live, and we are completely 00:01:34.569 --> 00:01:36.849 surrounded by it. I mean, the atmosphere is roughly 00:01:36.849 --> 00:01:40.370 78 % nitrogen gas. 78%, it's everywhere. But 00:01:40.370 --> 00:01:42.870 for the vast, vast majority of life on Earth, 00:01:43.329 --> 00:01:45.670 we are completely incapable of using it in that 00:01:45.670 --> 00:01:47.909 form. Yeah, it's a classic paradox of plenty. 00:01:48.269 --> 00:01:50.730 To understand why we can't just, you know, breathe 00:01:50.730 --> 00:01:52.549 it in and use it to build our bodies, we have 00:01:52.549 --> 00:01:55.329 to look at the underlying chemistry. Right. Atmospheric 00:01:55.329 --> 00:01:58.310 nitrogen, which is called dinitrogen or N2, consists 00:01:58.310 --> 00:02:01.269 of two nitrogen atoms, and they are held together 00:02:01.269 --> 00:02:04.290 by a triple covalent bond. And a triple bond 00:02:04.290 --> 00:02:06.250 is, well, exactly what it sounds like, right? 00:02:06.349 --> 00:02:08.490 They're sharing three pairs of electrons. Precisely. 00:02:08.689 --> 00:02:11.289 And in the world of chemistry, a triple bond 00:02:11.289 --> 00:02:14.210 is tremendously strong. Like super glue strong. 00:02:14.509 --> 00:02:16.909 Stronger. Those two nitrogen atoms are locked 00:02:16.909 --> 00:02:19.810 in this incredibly stable, highly unreactive 00:02:19.810 --> 00:02:22.900 death grip. they do not want to let go of each 00:02:22.900 --> 00:02:26.080 other to bond with anything else. So while this 00:02:26.080 --> 00:02:28.819 vital element is overwhelmingly abundant in the 00:02:28.819 --> 00:02:32.479 air, biologically speaking, it is entirely locked 00:02:32.479 --> 00:02:35.039 away behind a chemical vault. OK, let's unpack 00:02:35.039 --> 00:02:37.919 this. Imagine you are floating in a life raft 00:02:37.919 --> 00:02:39.960 in the middle of the ocean. OK. And you are dying 00:02:39.960 --> 00:02:42.900 of thirst. There is water everywhere, in every 00:02:42.900 --> 00:02:45.800 direction, as far as the eye can see. But you 00:02:45.800 --> 00:02:47.719 can't drink it because it's too salty. That's 00:02:47.719 --> 00:02:50.560 a great analogy. Right. So atmospheric nitrogen 00:02:50.560 --> 00:02:53.599 is our ocean. It is everywhere, but it's completely 00:02:53.599 --> 00:02:56.719 inaccessible to our bodies. And nitrogen fixation, 00:02:57.060 --> 00:02:59.280 the process we're talking about today, that is 00:02:59.280 --> 00:03:01.759 the desalination plant. Yeah. It's the process 00:03:01.759 --> 00:03:04.580 of taking that unusable ocean and turning it 00:03:04.580 --> 00:03:06.860 into something that actually sustains life. That 00:03:06.860 --> 00:03:09.639 is a perfect way to conceptualize it. And what's 00:03:09.639 --> 00:03:12.800 fascinating here is the sheer energy required 00:03:12.800 --> 00:03:15.639 to run that biological desalination plant. Because 00:03:15.639 --> 00:03:18.259 breaking that bond is hard. Incredibly hard. 00:03:18.479 --> 00:03:20.199 Breaking a triple bond doesn't just happen on 00:03:20.199 --> 00:03:22.639 its own. It requires an immense amount of chemical 00:03:22.639 --> 00:03:26.759 force. But the biological demand for it is absolutely 00:03:26.759 --> 00:03:29.979 relentless. Life needs it. Desperately. And we 00:03:29.979 --> 00:03:32.000 can see exactly how relentless through something 00:03:32.000 --> 00:03:35.080 called the Redfield ratio. Oh, right. Discovered 00:03:35.080 --> 00:03:38.060 by the scientist Alfred Redfield. Yes. So back 00:03:38.060 --> 00:03:41.669 in 1958, Redfield analyzed the biomass of plankton 00:03:41.669 --> 00:03:45.110 in the ocean, and he found a remarkably consistent 00:03:45.110 --> 00:03:47.469 stoichiometric relationship. A ratio of what 00:03:47.469 --> 00:03:49.550 they're made of. Exactly. He discovered that 00:03:49.550 --> 00:03:52.229 for every 100 atoms of carbon that plankton assimilate 00:03:52.229 --> 00:03:55.110 to build their bodies, they require roughly 16 00:03:55.110 --> 00:03:58.409 atoms of nitrogen and one atom of phosphorus. 00:03:58.870 --> 00:04:02.389 So the ratio is essentially 106 to 16 to 1. That 00:04:02.389 --> 00:04:05.229 means for every single piece of biological growth, 00:04:05.710 --> 00:04:08.530 nitrogen is in massive demand. Exactly. It is 00:04:08.530 --> 00:04:11.330 an absolute necessity for life to scale. Every 00:04:11.330 --> 00:04:13.889 time a cell divides, every time a strand of DNA 00:04:13.889 --> 00:04:16.850 is replicated, that nitrogen is required. But 00:04:16.850 --> 00:04:19.889 again, the supply is locked behind this impenetrable 00:04:19.889 --> 00:04:23.129 triple bond. Right. So this is the ultimate evolutionary 00:04:23.129 --> 00:04:27.930 bottleneck. If the bond is that strong and life 00:04:27.930 --> 00:04:30.589 desperately needs it to build DNA and proteins, 00:04:31.490 --> 00:04:33.439 nature had to figure out a way to break it. It 00:04:33.439 --> 00:04:36.160 had no choice. Which means life had to evolve 00:04:36.160 --> 00:04:39.660 a highly specialized, incredibly energy -intensive 00:04:39.660 --> 00:04:42.319 mechanism just to survive on this planet. And 00:04:42.319 --> 00:04:46.110 it did. Biological nitrogen fixation, or BNF, 00:04:46.370 --> 00:04:48.949 relies entirely on a highly complex enzyme. It's 00:04:48.949 --> 00:04:50.889 called nitrogenase. Nitrogenase, okay. Yeah, 00:04:50.889 --> 00:04:53.230 this is the biological key that unlocks the nitrogen 00:04:53.230 --> 00:04:55.649 vault. It converts that stubborn atmospheric 00:04:55.649 --> 00:04:58.189 nitrogen into ammonia. Which is the usable form. 00:04:58.310 --> 00:05:00.110 Right, ammonia is what organisms can actually 00:05:00.110 --> 00:05:02.009 use to build biological structures, but it does 00:05:02.009 --> 00:05:03.910 not come cheap. Yeah, the sources mention the 00:05:03.910 --> 00:05:06.350 cost in terms of ATP, and ATP is basically the 00:05:06.350 --> 00:05:08.670 cellular energy currency, right? Correct. ATP 00:05:08.670 --> 00:05:10.930 is how cells pay for things to get done, and 00:05:10.930 --> 00:05:14.170 it takes 16 equivalent... of ATP. Just to convert 00:05:14.170 --> 00:05:16.930 one single molecule of N2 into two molecules 00:05:16.930 --> 00:05:20.910 of ammonia. 16 ATP for one molecule. That's like 00:05:20.910 --> 00:05:23.149 paying 16 months of rent for a single cup of 00:05:23.149 --> 00:05:25.709 coffee. It really is. That is an outrageous energy 00:05:25.709 --> 00:05:28.370 bill for a microscopic organism to pay. just 00:05:28.370 --> 00:05:31.350 to get raw materials. It's a staggering metabolic 00:05:31.350 --> 00:05:34.310 cost, but the mechanism itself is an absolute 00:05:34.310 --> 00:05:37.589 marvel of evolution. Instead of trying to smash 00:05:37.589 --> 00:05:39.930 the triple bond all at once, the conversion happens 00:05:39.930 --> 00:05:42.889 at a very specific active site on the enzyme. 00:05:43.029 --> 00:05:45.670 Like a specific tool. Yeah, it's a metal cluster 00:05:45.670 --> 00:05:49.029 called FAMOCO, which stands for iron and molybdenum 00:05:49.029 --> 00:05:52.079 cofactor. And how exactly does that work? Because 00:05:52.079 --> 00:05:54.600 the sources mention protonation and reduction 00:05:54.600 --> 00:05:57.319 steps. But what does that actually look like 00:05:57.319 --> 00:06:00.040 inside the cell? Think of the FAMOCO metal cluster 00:06:00.040 --> 00:06:02.360 like a microscopic crowbar. A crowbar? Yeah, 00:06:02.360 --> 00:06:04.920 it doesn't shatter the bond instantly. Instead, 00:06:05.019 --> 00:06:07.600 it sneaks hydrogen atoms into the triple bond 00:06:07.600 --> 00:06:10.139 one by one. Oh, wow. It pries those two stubborn 00:06:10.139 --> 00:06:12.920 nitrogen atoms apart, click by click, adding 00:06:12.920 --> 00:06:15.180 hydrogens until the triple bond finally snaps. 00:06:15.439 --> 00:06:18.079 And that separates the nitrogens and forms ammonia. 00:06:18.399 --> 00:06:22.100 That is incredible. A microscopic cobar operating 00:06:22.100 --> 00:06:25.000 on an atomic level. Exactly. And based on the 00:06:25.000 --> 00:06:27.420 evolutionary timelines in our sources, this specific 00:06:27.420 --> 00:06:31.220 enzyme, nitrogenase, evolved somewhere between 00:06:31.220 --> 00:06:35.209 1 .5 and 2 .2 billion years ago. Though some 00:06:35.209 --> 00:06:37.350 isotopic evidence suggests it could be as old 00:06:37.350 --> 00:06:40.970 as 3 .2 billion years. Which is wild. And what's 00:06:40.970 --> 00:06:42.910 interesting about that timeline is the metals 00:06:42.910 --> 00:06:45.350 involved. Right, the iron and molybdenum. Yeah, 00:06:45.589 --> 00:06:48.189 the exact form of nitrogenase, whether it relies 00:06:48.189 --> 00:06:50.930 on molybdenum or sometimes vanadium or just pure 00:06:50.930 --> 00:06:53.629 iron, was likely driven by whatever specific 00:06:53.629 --> 00:06:56.480 metals were abundant. in the chemical soup of 00:06:56.480 --> 00:06:59.199 the ancient oceans. At those exact moments in 00:06:59.199 --> 00:07:01.800 Earth's geologic history. Right. Life literally 00:07:01.800 --> 00:07:03.920 used whatever tools it had lying around to build 00:07:03.920 --> 00:07:06.459 this crowbar. It's highly opportunistic. OK, 00:07:06.519 --> 00:07:08.259 wait. I'm struggling with the logistics here. 00:07:08.259 --> 00:07:11.000 Yeah. You just described this enzyme as an evolutionary 00:07:11.000 --> 00:07:13.079 miracle that took billions of years to perfect. 00:07:13.180 --> 00:07:15.800 It is. But the sources also clearly state that 00:07:15.800 --> 00:07:19.060 nitrogenase has a fatal flaw. It is rapidly degraded 00:07:19.060 --> 00:07:21.860 and destroyed by oxygen. Yeah. That is the great 00:07:21.860 --> 00:07:24.680 catch of biological nitrogen fixation. But how 00:07:24.680 --> 00:07:27.560 is that possible? Wait, if this enzyme is destroyed 00:07:27.560 --> 00:07:31.000 by oxygen and is the only biological way to access 00:07:31.000 --> 00:07:34.600 nitrogen, how is it surviving out in the open? 00:07:34.740 --> 00:07:37.339 It's a huge problem. Because we live on a planet 00:07:37.339 --> 00:07:40.240 covered in oxygen producing plants and breathing 00:07:40.240 --> 00:07:43.379 animals. Having an enzyme destroyed by oxygen 00:07:43.379 --> 00:07:45.910 seems like I don't know, trying to build a matchstick 00:07:45.910 --> 00:07:48.350 house inside a blast furnace. It really does 00:07:48.350 --> 00:07:50.889 seem impossible, but it's a brilliant biological 00:07:50.889 --> 00:07:54.509 puzzle. And nature came up with a series of incredibly 00:07:54.509 --> 00:07:57.610 intricate localized workarounds to solve it. 00:07:57.670 --> 00:08:00.490 OK, like what? Well, since many bacteria cease 00:08:00.490 --> 00:08:02.829 producing the enzyme the second oxygen is present, 00:08:03.170 --> 00:08:05.329 they had to adapt based on their environments. 00:08:05.850 --> 00:08:09.209 Some, like obligate anaerobic bacteria, simply 00:08:09.209 --> 00:08:11.829 live in environments entirely devoid of oxygen. 00:08:12.069 --> 00:08:14.459 Oh, so just hiding from it. Exactly, deep in 00:08:14.459 --> 00:08:16.459 the mud or at the bottom of the ocean, problem 00:08:16.459 --> 00:08:18.439 solved. Sure, but what about the bacteria that 00:08:18.439 --> 00:08:20.680 live right out in the open air or water? That's 00:08:20.680 --> 00:08:23.639 where evolution gets highly creative. Take cyanobacteria, 00:08:23.660 --> 00:08:26.360 for example. These are photosynthetic bacteria. 00:08:26.759 --> 00:08:29.100 They inhabit almost all illuminated environments 00:08:29.100 --> 00:08:32.120 on Earth, and they actually produce oxygen themselves. 00:08:32.440 --> 00:08:36.250 Wait, they make oxygen? But they need the enzyme 00:08:36.250 --> 00:08:39.029 that oxygen destroys. Yes. So to protect their 00:08:39.029 --> 00:08:41.429 delicate nitrogenase from the very oxygen they 00:08:41.429 --> 00:08:44.830 are pumping out, species like affenzomenon and 00:08:44.830 --> 00:08:48.250 dolicospermum develop specialized thick -walled 00:08:48.250 --> 00:08:51.309 oxygen -free cells. They're called heterocysts. 00:08:51.389 --> 00:08:53.970 So they literally build a sealed panic room just 00:08:53.970 --> 00:08:57.169 to fix nitrogen. Exactly. They create a microscopic 00:08:57.169 --> 00:08:59.389 panic room where the oxygen can't penetrate, 00:08:59.429 --> 00:09:01.690 and that is the only place where the nitrogenase 00:09:01.690 --> 00:09:04.450 crowbar goes to work. That is wild. And what 00:09:04.450 --> 00:09:07.169 about plants? Because we constantly hear about 00:09:07.169 --> 00:09:11.509 farmers planting certain crops to put nitrogen 00:09:11.509 --> 00:09:13.250 back into the soil. Well, technically the plants 00:09:13.250 --> 00:09:15.370 don't fix it themselves. Or they don't. No, they 00:09:15.370 --> 00:09:17.389 form symbiotic relationships with the bacteria 00:09:17.389 --> 00:09:19.889 that possess the enzyme. The most famous examples 00:09:19.889 --> 00:09:22.570 of this are legumes. Think of crops like clover, 00:09:22.850 --> 00:09:26.059 soybeans, alfalfa, peanuts. Good zoo. Right, 00:09:26.100 --> 00:09:28.840 could do too. These plants form little root nodules 00:09:28.840 --> 00:09:31.620 that act as housing for rhizobia bacteria. Okay, 00:09:31.620 --> 00:09:34.740 so they give the bacteria home. Yes. But to solve 00:09:34.740 --> 00:09:37.740 the oxygen problem inside those nodules, the 00:09:37.740 --> 00:09:40.879 plant does something amazing. It produces a specialized 00:09:40.879 --> 00:09:43.879 protein called ligamaglobin. Ligamaglobin? That 00:09:43.879 --> 00:09:46.779 sounds like hemoglobin. It's structurally very 00:09:46.779 --> 00:09:48.820 similar to the hemoglobin running through your 00:09:48.820 --> 00:09:51.320 own blood right now. Okay, so what does ligamaglobin 00:09:51.320 --> 00:09:54.259 do inside a plant root? It acts as an oxygen 00:09:54.259 --> 00:09:57.740 scavenger. It binds to the ambient oxygen inside 00:09:57.740 --> 00:10:00.960 the nodule, keeping it safely away from the sensitive 00:10:00.960 --> 00:10:03.820 nitrogenase enzyme. Oh, wow. But it still allows 00:10:03.820 --> 00:10:06.559 the bacteria just enough oxygen to respire and 00:10:06.559 --> 00:10:08.960 survive. So the plant essentially puts the oxygen 00:10:08.960 --> 00:10:12.000 on a molecular leash. It keeps it perfectly suspended 00:10:12.000 --> 00:10:14.200 so the bacteria can breathe, but it can't touch 00:10:14.200 --> 00:10:16.960 the enzyme. Precisely. It's an elegant solution, 00:10:17.059 --> 00:10:19.220 and this sort of biological hacking isn't just 00:10:19.220 --> 00:10:21.950 ancient history either. No. No, it's an ongoing 00:10:21.950 --> 00:10:24.730 evolutionary process. The sources highlight a 00:10:24.730 --> 00:10:27.230 mind -blowing recent discovery in a species of 00:10:27.230 --> 00:10:30.809 marine algae called Borutosphera bigeloi. Oh, 00:10:30.929 --> 00:10:34.049 the nitroplast. Yes. Scientists found an organelle 00:10:34.049 --> 00:10:37.049 inside this algae called a nitroplast, and it 00:10:37.049 --> 00:10:39.950 originated from a cyanobacterium known as UCYNA. 00:10:40.190 --> 00:10:41.889 Let me make sure I'm wrapping my head around 00:10:41.889 --> 00:10:46.009 this. An organelle -like, how mitochondria are 00:10:46.009 --> 00:10:48.649 organelles functioning as the powerhouse of our 00:10:48.649 --> 00:10:51.450 cells. Exactly like that. Wow. What this implies 00:10:51.450 --> 00:10:54.289 is that a free -living nitrogen -fixing bacterium 00:10:54.289 --> 00:10:56.690 was at some point engulfed by the algae? Like 00:10:56.690 --> 00:10:59.750 it ate. Basically. But over time, instead of 00:10:59.750 --> 00:11:02.529 being digested as food, it became a permanent 00:11:02.720 --> 00:11:05.379 integrated part of the cell's machinery. That's 00:11:05.379 --> 00:11:08.379 crazy. Its sole dedicated purpose is now turning 00:11:08.379 --> 00:11:11.379 nitrogen gas into a biologically available form 00:11:11.379 --> 00:11:13.860 for the host cell. We are literally watching 00:11:13.860 --> 00:11:16.419 the evolution of a new cellular organelle happening 00:11:16.419 --> 00:11:19.240 right in front of us. OK, so nature's hackers, 00:11:19.779 --> 00:11:22.419 these deep mud bacteria, the microscopic panic 00:11:22.419 --> 00:11:24.980 rooms, the root nodules, they figured out how 00:11:24.980 --> 00:11:27.200 to make this desalination plant work. They did. 00:11:27.360 --> 00:11:29.659 But here's the massive structural problem that 00:11:29.659 --> 00:11:32.870 changed human history. Biological fixation is 00:11:32.870 --> 00:11:36.309 an incredibly slow, painstaking process. Very 00:11:36.309 --> 00:11:38.970 slow. A clover field can only fix so much nitrogen 00:11:38.970 --> 00:11:41.429 in a season. That's right. It has a strict capacity 00:11:41.429 --> 00:11:44.970 limit. And as human civilization developed... 00:11:44.990 --> 00:11:47.870 and our population started to multiply, we hit 00:11:47.870 --> 00:11:51.149 a terrifying mathematical wall. A huge wall. 00:11:51.309 --> 00:11:53.690 We simply needed more nitrogen to grow our crops 00:11:53.690 --> 00:11:55.730 than the bacteria in the soil could biologically 00:11:55.730 --> 00:11:58.350 fix. Without more fixed nitrogen, the carrying 00:11:58.350 --> 00:12:00.970 capacity of the earth for human life was hard 00:12:00.970 --> 00:12:04.049 capped. By the 19th century, the soil in Europe 00:12:04.049 --> 00:12:06.230 and North America was running out of nutrients. 00:12:06.309 --> 00:12:09.009 It was exhausted. Completely. We were facing 00:12:09.009 --> 00:12:11.330 a future where we simply could not grow enough 00:12:11.330 --> 00:12:13.950 food to feed the booming population. Which means 00:12:13.950 --> 00:12:16.559 humanity had to look beyond biology. We had to 00:12:16.559 --> 00:12:18.879 figure out a way to break that triple bond ourselves. 00:12:19.220 --> 00:12:22.220 Yes. And ironically, before human chemists cracked 00:12:22.220 --> 00:12:25.580 the code, there was basically only one major 00:12:25.580 --> 00:12:28.539 non -biological way nitrogen ever got fixed on 00:12:28.539 --> 00:12:31.679 Earth. Lightning. Atmospheric fixation. It's 00:12:31.679 --> 00:12:34.379 a brilliant, violent alternative to the slow 00:12:34.379 --> 00:12:36.620 biological enzyme. How does that work? Well, 00:12:36.799 --> 00:12:39.759 when a lightning bolt strikes, the extreme localized 00:12:39.759 --> 00:12:42.240 heat of the plasma generates enough sheer energy 00:12:42.240 --> 00:12:45.080 to violently rip those unyielding N2 triple bonds 00:12:45.080 --> 00:12:47.240 apart. So the sheer temperature just overpowers 00:12:47.240 --> 00:12:50.480 the bond. Exactly. Once shattered, those freed 00:12:50.480 --> 00:12:53.299 nitrogen atoms immediately react with the oxygen 00:12:53.299 --> 00:12:56.519 in the air, forming nitrogen oxides. As those 00:12:56.519 --> 00:12:59.159 molecules cool down and interact with water vapor 00:12:59.159 --> 00:13:01.850 in the atmosphere, they eventually form nitrous 00:13:01.850 --> 00:13:04.870 or nitric acid, which then rains down into the 00:13:04.870 --> 00:13:07.230 soil as usable nitrates. Here's where it gets 00:13:07.230 --> 00:13:09.350 really interesting, because when you look at 00:13:09.350 --> 00:13:12.409 the early human attempts to artificially fix 00:13:12.409 --> 00:13:15.289 nitrogen, those scientists were essentially trying 00:13:15.289 --> 00:13:17.850 to build machines to bottle lightning. They really 00:13:17.850 --> 00:13:20.090 were. Our sources mentioned Henry Cavendish way 00:13:20.090 --> 00:13:23.230 back in 1784. Yes, Cavendish was one of the first 00:13:23.230 --> 00:13:25.750 to truly experiment with this. He was literally 00:13:25.750 --> 00:13:28.809 using electric arcs to react nitrogen and oxygen 00:13:28.809 --> 00:13:32.049 in the air. inside glass tubes. He was trying 00:13:32.049 --> 00:13:34.269 to mimic a thunderstorm in a laboratory. It was 00:13:34.269 --> 00:13:36.850 very crude, but the concept was sound. And that 00:13:36.850 --> 00:13:38.830 same underlying concept was eventually scaled 00:13:38.830 --> 00:13:41.409 up into the Birkeland -Ide process in 1903. But 00:13:41.409 --> 00:13:43.809 these early methods were incredibly inefficient. 00:13:44.070 --> 00:13:46.529 It was a desperate quest. Humanity was watching 00:13:46.529 --> 00:13:49.509 its population grow and realizing the agricultural 00:13:49.509 --> 00:13:52.559 collapse was imminent. The pressure was on. Huge 00:13:52.559 --> 00:13:54.879 pressure. The historical progression of these 00:13:54.879 --> 00:13:58.000 experiments reflects this escalating, almost 00:13:58.000 --> 00:14:01.440 frantic search for a chemical solution. Right, 00:14:01.639 --> 00:14:03.820 because electricity wasn't cutting it. So they 00:14:03.820 --> 00:14:06.279 turned to brute force chemistry. Exactly. In 00:14:06.279 --> 00:14:09.600 the 1860s, you had chemists Marguerite and Saradaval. 00:14:09.960 --> 00:14:12.519 They took barium carbonate and reacted it with 00:14:12.519 --> 00:14:14.720 nitrogen gas at intensely high temperatures to 00:14:14.720 --> 00:14:17.580 produce barium cyanide. Oh, wow. Which they would 00:14:17.580 --> 00:14:20.080 then react with steam to finally get ammonia. 00:14:20.279 --> 00:14:22.700 That sounds like a tremendously complicated workaround. 00:14:22.820 --> 00:14:25.820 It was. And it was followed in 1898 by the Frank 00:14:25.820 --> 00:14:28.740 Carroll process, which created calcium cyanamide. 00:14:29.000 --> 00:14:31.600 Every iteration, every new chemical process was 00:14:31.600 --> 00:14:34.019 a desperate attempt to find an industrial way 00:14:34.019 --> 00:14:36.649 to pry that triple bond. open and feed the dying 00:14:36.649 --> 00:14:39.250 crops. But all of those electric arcs and barium 00:14:39.250 --> 00:14:41.889 experiments were just a warm -up. They were completely 00:14:41.889 --> 00:14:44.909 eclipsed by a single brutal chemical process 00:14:44.909 --> 00:14:47.289 that fundamentally changed the trajectory of 00:14:47.289 --> 00:14:48.909 the human race forever. You're talking about 00:14:48.909 --> 00:14:51.269 the Haber process, widely known as the Haber 00:14:51.269 --> 00:14:54.870 -Bosch process, discovered in 1909. Yes, 1909. 00:14:55.149 --> 00:14:56.970 You want to talk about humanity brute -forcing 00:14:56.970 --> 00:14:59.330 nature. This is the ultimate example. It really 00:14:59.330 --> 00:15:02.149 is. To do exactly what tiny rhizobia bacteria 00:15:02.149 --> 00:15:05.350 do calmly at room temperature inside a delicate 00:15:05.350 --> 00:15:08.879 clover root The Haber -Bosch process requires 00:15:08.879 --> 00:15:11.720 conditions that sound like they belong on the 00:15:11.720 --> 00:15:14.379 surface of Venus. The conditions are remarkably 00:15:14.379 --> 00:15:17.059 violent. We are talking about 200 atmospheres 00:15:17.059 --> 00:15:21.120 of pressure inside massive steel reactors. For 00:15:21.120 --> 00:15:23.360 context, that is the kind of crushing pressure 00:15:23.360 --> 00:15:25.679 you would experience if you were thousands of 00:15:25.679 --> 00:15:27.460 feet underwater at the bottom of the ocean. Just 00:15:27.460 --> 00:15:29.620 immense pressure. And it operates at temperatures 00:15:29.620 --> 00:15:32.220 of at least 400 degrees Celsius. Yeah. which 00:15:32.220 --> 00:15:35.279 is hot enough to melt lead. It uses massive amounts 00:15:35.279 --> 00:15:38.659 of natural gas as a sort for hydrogen and literally 00:15:38.659 --> 00:15:42.120 pulls the air around us into the machine as a 00:15:42.120 --> 00:15:44.620 source for nitrogen. It is the absolute definition 00:15:44.620 --> 00:15:47.779 of severe industrial catalysis. They use an iron 00:15:47.779 --> 00:15:50.299 -based catalyst, forcing the nitrogen and hydrogen 00:15:50.299 --> 00:15:52.639 gases together under that immense heat and pressure. 00:15:52.759 --> 00:15:54.620 Until the bond just gives up. Until the triple 00:15:54.620 --> 00:15:57.100 bond breaks and ammonia is formed. And the reality 00:15:57.100 --> 00:15:59.100 is... It worked. It worked perfectly. It worked 00:15:59.100 --> 00:16:01.919 so well, it literally reshaped the planet. Today, 00:16:02.220 --> 00:16:05.179 that single industrial method underpins the manufacture 00:16:05.179 --> 00:16:08.399 of virtually all nitrogenous industrial products 00:16:08.399 --> 00:16:10.600 globally. That's crazy to think about. We are 00:16:10.600 --> 00:16:12.740 talking about the foundation of modern synthetic 00:16:12.740 --> 00:16:16.659 fertilizers, which is its primary use. But the 00:16:16.659 --> 00:16:19.240 ammonia produced by Haber -Bosch is also the 00:16:19.240 --> 00:16:23.399 precursor for pharmaceuticals, textiles, commercial 00:16:23.399 --> 00:16:27.059 dyes, and crucially, given the history of the 00:16:27.059 --> 00:16:31.009 20th century, explosives and munitions. So what 00:16:31.009 --> 00:16:33.549 does this all mean for us today? Our sources 00:16:33.549 --> 00:16:36.230 credit this exact process with supporting the 00:16:36.230 --> 00:16:39.009 rapid, unprecedented expansion of the human population. 00:16:39.049 --> 00:16:42.070 Yes. We went from roughly 2 billion people in 00:16:42.070 --> 00:16:44.850 the early 20th century to the 8 billion people 00:16:44.850 --> 00:16:47.480 alive right now. That is the direct result of 00:16:47.480 --> 00:16:49.419 synthetic fertilizer. Let me just make sure I 00:16:49.419 --> 00:16:51.940 am truly understanding the scale of this. Does 00:16:51.940 --> 00:16:53.980 this mean that out of the 8 billion people walking 00:16:53.980 --> 00:16:57.360 the earth today, roughly 6 billion of us literally 00:16:57.360 --> 00:17:00.139 only exist because of a violent chemical factory 00:17:00.139 --> 00:17:02.639 process invented in 1909? If we connect this 00:17:02.639 --> 00:17:05.140 to the bigger picture, yeah. That is the stark 00:17:05.140 --> 00:17:07.779 mathematical reality. Unbelievable. Fertilizer 00:17:07.779 --> 00:17:10.799 production via Haber -Bosch is now the largest 00:17:10.799 --> 00:17:13.619 source of human -produced fixed nitrogen in the 00:17:13.619 --> 00:17:17.700 entire terrestrial ecosystem. Because we synthesized 00:17:17.700 --> 00:17:20.779 this process, we removed the biological speed 00:17:20.779 --> 00:17:23.220 limit. We hacked the system. We were able to 00:17:23.220 --> 00:17:26.119 grow food at a scale nature never, ever intended. 00:17:26.299 --> 00:17:29.000 That is mind -bending. Which means a massive, 00:17:29.000 --> 00:17:31.519 massive percentage of the nitrogen atoms currently 00:17:31.519 --> 00:17:35.099 sitting inside your own DNA, the structural backbone 00:17:35.099 --> 00:17:37.259 of the proteins making up your muscles, your 00:17:37.259 --> 00:17:39.960 skin, your heart. At some point in the recent 00:17:39.960 --> 00:17:43.220 past, those exact atoms passed through a high 00:17:43.220 --> 00:17:46.660 -pressure, 400 -degree steel reactor in an industrial 00:17:46.660 --> 00:17:49.230 chemical plant. That is almost terrifying to 00:17:49.230 --> 00:17:51.970 think about. We are quite literally industrial 00:17:51.970 --> 00:17:54.269 products walking around in organic bodies. We 00:17:54.269 --> 00:17:56.329 are completely tethered to the infrastructure 00:17:56.329 --> 00:17:58.529 we created. Without the Haber -Bosch process 00:17:58.529 --> 00:18:00.950 running constantly across the globe, the global 00:18:00.950 --> 00:18:03.029 food supply would collapse almost overnight. 00:18:03.170 --> 00:18:06.450 Wow. We outgrew nature's desalination plant a 00:18:06.450 --> 00:18:08.349 century ago. OK, let's bring this all together. 00:18:08.650 --> 00:18:12.109 We started with a stubborn locked away gas that 00:18:12.109 --> 00:18:15.480 makes up almost 80 % of our atmosphere. A molecule 00:18:15.480 --> 00:18:18.099 bound so tightly, it is basically useless to 00:18:18.099 --> 00:18:21.380 us in its natural form. Right. We saw how ancient 00:18:21.380 --> 00:18:25.380 biology fought an eons -long war, evolving highly 00:18:25.380 --> 00:18:28.440 sensitive enzymes like nitrogenase, utilizing 00:18:28.440 --> 00:18:31.279 microscopic crowbars to pry atoms apart. And 00:18:31.279 --> 00:18:34.619 building literal panic rooms inside cells just 00:18:34.619 --> 00:18:37.420 to protect those enzymes from oxygen. And then 00:18:37.420 --> 00:18:40.690 we saw how humanity faced with mass starvation 00:18:40.690 --> 00:18:42.809 and a hard mathematical limit on our own growth, 00:18:43.349 --> 00:18:46.089 decided to bypass biology entirely. We forced 00:18:46.089 --> 00:18:48.990 our way through. We used extreme heat, incredible 00:18:48.990 --> 00:18:51.250 crushing pressure, and vast amounts of fossil 00:18:51.250 --> 00:18:53.450 fuels to mimic the shattering energy of lightning. 00:18:53.930 --> 00:18:56.089 We forced that molecule apart to feed the world. 00:18:56.289 --> 00:18:58.730 It is an incredible journey. But the text does 00:18:58.730 --> 00:19:00.730 mention that scientists are actively struggling 00:19:00.730 --> 00:19:03.410 to find better ways to do this. Right. There's 00:19:03.410 --> 00:19:06.059 a whole field called homogenous catalysis. where 00:19:06.059 --> 00:19:07.859 researchers are desperately searching for low 00:19:07.859 --> 00:19:09.900 -energy catalysts to fix nitrogen. They want 00:19:09.900 --> 00:19:12.539 to figure out how to do what tiny cyanobacteria 00:19:12.539 --> 00:19:15.240 do at room temperature. But on an industrial 00:19:15.240 --> 00:19:18.359 scale. So we aren't so reliant on the massive 00:19:18.359 --> 00:19:21.279 energy demands of Haber -Bosch. It is the holy 00:19:21.279 --> 00:19:24.099 grail of modern chemistry. Can we crack the code 00:19:24.099 --> 00:19:26.900 to artificially fix nitrogen as efficiently and 00:19:26.900 --> 00:19:29.680 elegantly as nature does? Exactly. So the next 00:19:29.680 --> 00:19:31.519 time you sit down to eat a piece of bread or 00:19:31.519 --> 00:19:34.119 a bowl of rice or literally anything containing 00:19:34.119 --> 00:19:36.940 soybeans, Remember that you are experiencing 00:19:36.940 --> 00:19:39.940 the end result of an evolutionary and industrial 00:19:39.940 --> 00:19:43.519 battle to break a single molecular bond. Every 00:19:43.519 --> 00:19:46.119 bite you take is a tiny victory over the physics 00:19:46.119 --> 00:19:49.200 of the nitrogen atom. Surviving only because, 00:19:49.400 --> 00:19:52.380 somehow, we learn to build the plant. But before 00:19:52.380 --> 00:19:54.880 we go, consider this one final thought. Because 00:19:54.880 --> 00:19:57.519 we are now artificially pumping millions of tons 00:19:57.519 --> 00:20:00.200 of this synthetic nitrogen into the earth every 00:20:00.200 --> 00:20:03.099 single year to grow our food, it isn't just staying 00:20:03.099 --> 00:20:05.200 neatly in our crops. No, it definitely isn't. 00:20:05.279 --> 00:20:07.339 It is bleeding into our soil, running off into 00:20:07.339 --> 00:20:09.900 our rivers, and flooding our oceans. We are fundamentally 00:20:09.900 --> 00:20:12.839 altering ancient ecosystems that haven't experienced 00:20:12.839 --> 00:20:15.339 this level of free nitrogen in billions of years. 00:20:15.460 --> 00:20:18.039 It's a massive shift. We solved the bottleneck 00:20:18.039 --> 00:20:21.380 of human survival, yes. But we might have accidentally 00:20:21.380 --> 00:20:24.000 started a brand new biological war in the process. 00:20:24.940 --> 00:20:26.359 Something to think about the next time you look 00:20:26.359 --> 00:20:29.400 at the ingredients on your plate. Thanks for 00:20:29.400 --> 00:20:31.920 diving deep with us today. Keep looking at the 00:20:31.920 --> 00:20:33.079 invisible world around you.