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Nick Lane

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Nick Lane, 2017

Nick Lane (born 1967) is a British biochemist and writer. He is a professor in evolutionary biochemistry at University College London. He has published five books to date which have won several awards.

Quotes

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Power, Sex, Suicide (2005)

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: Mitochondria and the Meaning of Life
  • Mitochondria are a badly kept secret. ...There are usually hudreds or thousands of them in a single cell, where they use oxygen to burn up food. ...[O]ne billion ...would fit comfortably on a grain of sand.
  • [T]he 'mitochondrial theory of ageing' contends that ageing and many of... [its associated] diseases... are caused by... free radicals leaking from mitochondria during normal cellular respiration. ...As they burn up food using oxygen, the free-radical sparks escape to damage adjacent structures ...Many cruel inherited conditions... are linked with mutations caused by free radicals attacking mitochondrial genes.
  • From around the mid 1990s, researchers discovered that apoptosis is... governed... by the mitochondria. ...[T]he failure to commit apoptosis is the root cause of cancer. ...In cancer, individual cells bid for freedom ...Without programmed cell death, the bonds that bind cells in complex multicellular organisms might never have ebvolved.
  • [A]ll multicellular plants and animals... contain mitochondria.
  • Different species have transferred different genes to the nucleus, but all species with mitochondria have... retained... the same core contingent of mitochondrial genes.
  • [L]ife will probably get stuck in a bacterial rut elsewhere in the universe... we might not be alone, but will almost certainly be lonely.
  • This membrane, so vanishingly thin, looms large... for bacteria use it for generating their energy.
  • [B]acteria, the simplest of cells, are... so complex that we still have almost everything to learn about their invisible organization.
  • The possessors of... nuclei, the eukaryotes, are the most important cells in the world. ...[A]ll plants and animals, all algae and fungi... essentially everything we can see with the naked eye, is composed of [them]...
  • In bacteria, the DNA forms into a long and twisted loop. The contorted tracks... close... to form a singular circular chromosome. In eukaryotic cells, there are usually a number of different chromosomes... each has two separate ends.
  • [N]o bacteria coat their DNA with histones: their DNA is naked. The histones not only protect eukaryotic DNA from chemical attack, but also guard access to the genes.
  • The information encoded in DNA spells out the molecular structure of proteins. This, said Crick, is the 'central dogma' of all biology: genes code for proteins.
  • The sequence of letters in a gene specifies the sequence of amino acids in a protein. If the sequence of letters is changed—a 'mutation'—this may change the structure of the protein (...not always, there is some redundancy... technically degeneracy..—several combinations... can code for the same amino acid.)
  • Proteins are the crowning glory of life. ...[T]he rich variety of life is almost entirely attributable to the... variety of proteins. ...Perhaps the most important group are the enzymes ...biological catalysts that speed up the rate of biochemical reactions ...with an astonishing degree of selectivity for ...raw materials.
  • The DNA code is inert... stored safely... For daily use the cell relies on disposable photocopies... made of RNA... composed of similar building blocks... spun out on a single strand rather than the... double helix.

Nick Lane (Oct 3, 2021)

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A Creative Commons Attribution license video from the Youtube channel, "Are We Alone?" (@arewealone8944)
  • Does it make sense that life is cellular? Would you expect to find life being cellular elsewhere? I suspect that for organic life... it would be cellular.
    • 2:12
  • Whether or not it would be possible to drive the kind of protein machinery that you see in modern cells, like an ATP synthase... that makes the energy currency of life... If it were just sitting there in a membrane in a vent, can work out whether the natural... ion gradients in these vents would be... powerful enough to drive this machine to work. ...[Y]ou need to know what are the substrates, what are... the materials that it needs to operate? Where are they coming from? What's the concentration of them? You realize that you have no answer to any of those, and then what's the product? Well, it disappears off somewhere else, as well. So how can selection act if you've got stuff coming in from some unknown place and the product leaving to some unknown place? It made me realize that cellularization is important as a way of keeping the inside in and in keeping the outside out, and so I now have problems with the idea of seeing the entire vent as a kind of a living system.
    • 3:13
  • [T]here's a limit to just how far vents can take you... but... once you've gotten as far as photosynthesis, then you've freed yourself from a fairly small energy flow, a fairly tight and focused energy flow.
    • 4:43
  • It does seem to me, from our experience of life on earth that photosynthesis allows you to... step up, by probably orders of magnitude in just how much life can take over a planet.
    • 5:45
  • It would be a little disappointing if we didn't even find bacteria in our own solar system. I would be rather surprised to find what I would describe as large, morphologically complex life. ...It only arose once on earth. That doesn't necessarily mean that it's improbable... but it does raise some interesting questions about why, and... I think we can apply principles to it, and those principles effectively are why do bacteria and archaea, as assistive groups to the bacteria... They're biochemically very complex. They're genetically very complex. They're kind of structured in a different way where they have large, complex metagenomes, but... I doubt very much that we'll ever find anything of the [morphological] level of complexity of a flea, composed of bacterial cells.
    • 6:06
  • One stromatolite is pretty much the same as another stromatolite, to my eye. That probably gets the stromatolite biologists in a fury, I suspect...
    • 7:19
  • I'm not particularly... eucaryocentric, but I do think there is a problem to solve there. ...There is a difference in morphology ...
    • 7:35
  • To me it [we] means life as a whole, so I would include bacteria in we. ...Life on earth is a whole, yes I think so. We share the genetic code. We share the same cell structures. I feel quite a strong fellow feeling with bacteria.
    • 7:50
  • If we, meaning humans now... find life somewhere else, most people would be disappointed if it turned out only to be bacteria.
    • 8:26
  • What is [life] it? Would we even recognize it. What I imagine we would find would be cell-like things. Not a million miles away from bacteria, using carbon, probably in water, not because it's the only way of organizing. It's just that carbon is very good at that kind of chemistry. It's very common in the universe. Water is ubiquitous. We know, from the principles of life on earth, that all this stuff works and we know that it's thermodynamically favored. ...[J]ust statistically, I would expect, maybe 900 times out of a thousand that life would be organized in a similar way to life here. That's not to say it can't be different. It's just probably... going to be similar.
    • 8:45
  • I would define complexity, not really as genetic complexity because if you take it purely as genetic complexity, E. coli... a single cell may have 4,000 genes but the metagenome, the pool of genes in E. coli around the place may be on the order to 30,000 or more... [T]hat's the level of complexity equivalent to the human genome, or even more complex than the human genome, but it's organized and structured in a different way. ...You might say that it's structured in a similar way to an ant colony... but I think an ant colony has taken that level of Eusocial behavior a long way beyond anything you would see in E. coli. So I would define it as morphologically complex, meaning cells are larger and have a lot of stuff in them.
    • 10:01
  • [W]e are biochemically quite simple in comparison bacteria. Simpler than bacteria. In terms of our metabolic biochemistry we are really limited. ...[W]e have ...across the entire domain of eukaryotes, about the same degree of metabolic sophistication as a single bacterial cell.
    • 10:49
  • They [bacteria] haven't used it [their more complex metabolism]... to give rise to more complex morphologies beyond the kind of stromatolite type structures, beyond biofilms. That seems to be a limit. Some multicellularity, some degree of differentiation and complexity, but nothing... to compare with the flea.
    • 11:15
  • I think we share consciousness right across... not just even the animal world. I would see it going down even to the level of cells, some kind of flickering of consciousness. So I don't feel alone on earth, but I do think that there is something different about humans.
    • 12:37
  • We also have a power to destroy the earth, and... it's probably unique. ...Destroy ourselves, destroy a large part of life in earth, not the bacteria... If we take ourselves out, we'll give it five million years and it will be indistinguishable, apart from ourselves.
    • 12:58
  • I'm... interested in the principles of what governs the emergence of life on the planet, with a certain set of resources. Can we understand it? We'll never know what happened, so we'll never know how life started on earth. ...[I]f those principles are enormously difficult, if it turns out that it's a freak statistical accident, then there's little point in studying it and we will gain... very little. If, on the other hand, those principles are reasonable, intelligible, that we can study them in the lab and demonstrate that the steps that we propose are plausible and... we can demonstrate it, then I think that's as close to understanding the origin of life [as] we can get. ...[I]f those principles are generalizable, then as a scientist, that's... a pleasing thing. I'm not sure there's any more that's more pleasing to me, personally as a scientist.
    • 13:35
  • [W]e can't agree among ourselves, as an origins of life community, what were the conditions... under which life arose on earth. ...Within the field itself, probably the leading candidate... would be terrestrial geothermal systems, starting with cyanide and powered by UV radiation. There's been a lot of rather beautiful chemistry... in a terrestrial environment in some kind of geothermal pool... and cyanide chemistry, it works well as chemistry. The problem I have with that is that it doesn't link up very well to biochemistry of cells. I'm a biochemist and I would like to see some continuity between geochemistry and biochemistry, and there's not much there, to me. That doesn't mean that it's wrong. It's just that... [I] would like to see some continuity.
    • 14:54
  • What does life do then? ...it seems reasonable that the earliest forms of life were autotrophic... [i.e.,] they grew from gases... found in normal geological environments through an energy flux which is equivalent to cells which we see today, which is to say, what all life does today. There's a very simple phrase from Mike Russell... "hydrogenate CO2"... [i.e.,] add hydrogen onto carbon dioxide to make organic molecules. That is the structure of biochemistry in cells, and different cells can get hydrogen from all kinds places. They can strip it out of water. They can get it from hydrogen sulfide, but it also comes bubbling out of the ground as hydrogen gas, and that seems to be the simplest form of life imaginable as... life on earth. It's reacting hydrogen and CO2, and they don't react easily. The way that cells make them react... is to effectively use an electrical charge on a membrane... [T]here are environments like deep sea hydrothermal vents that provide... for free with an equivalent electrical charge across a barrier, and I think... that's the way to see the question.
  • [Life is] a continuum. I think there are some phase transitions, probably, and the origin of... genetic information is probably one of them. ...[W]e are doing some modeling work to try and work out how evolvable... a geological system [can] be along the path to getting to cell-like things that... most people would understand as life. How far can you go down that line before you have genetic inheritance? ...[A] long way, but you get to a point where... it's no longer evolvable. ...[I]n our modeling, you can get to a point where you're capable of producing protocells capable of making copies of themselves with a degree of sophistication, but getting beyond that, to specializing to different niches and so on, I don't see the way, without genetic inheritance.
    • 17:23
  • I deliberately avoid having... [a working definition of life]. What I quote... is... from Peter Mitchell... a pioneer... of... membrane bioenergetics, that essentially all cells, with very very few exceptions, are powered by... proton gradients across the membrane. So on one side of the membrane surrounding the cell you've got the high proton concentration on the inside, a low proton concentration [on the outside]. Protons are... the positively charged nuclei of hydrogen atoms, so... [y]ou're pumping them out and... putting a charge on the membrane... That's as universally conserved across life on earth as the genetic code itself, which implies, as a mechanism, it's very early... [I]t's not something anyone ever predicted. It's not something that... emerges from a chemical understanding of the biochemistry of cells.
  • It could be any of those [sodium, calcium or other ion gradients]. The fact of life on earth is that it tends to use proton gradients, and we know particular environments that do use proton gradients, and the reason I think protons is because pH, which is to say the proton concentration, can modulate the reactivity of both carbon dioxide and hydrogen. Now sodium concentrations wouldn't do that, but protons, if you've got hydrogen gas in alkaline fluids, hydrothermal fluids... what you've got coming out of these hydrothermal vents, hydrogen is more reactive in alkaline conditions. It really doesn't want to push its electrons onto something else, but if it's in alkaline conditions it pushes its electrons onto something else, and the protons are left behind and they will react immediately with the hydroxide ions to form water, which is thermodynamically very favored, and so it's far more likely to push its electrons onto CO2 if it's in alkaline solution.
  • Now CO2 itself... doesn't really want to pick up any electrons and become reduced to an organic molecule, but if it's in a relatively acidic environment where there's protons available, it picks up a negative charge. It doesn't want another negative charge. It's going to try and repel that, but if there's a proton around, it picks up the proton. Now it's neutralized the charges... pick up another electron, another proton. So it's much easier to accept electrons in an acidic environment. And this is the structure of these vents and it's the structure of cells, and it's how these earliest, most ancient cells we know about actually do fix CO2. They use the proton channel in the membrane, which effectively locally acidifies an environment and allows this reaction to proceed. So I think that's fundamental, simple... works well, and it's testable in the lab.
  • We've had some success and quite a lot of failure too. ...[T]he problem we're having... is reproducing the successes we have had. The big problem... for anyone working on this is that hydrogen gas is not soluble in water at atmospheric pressure. What we really need to do to make this work is to ramp up the pressure in the system to 300 bars and then we need a continuous flow. For this to work you need a laminar flow across a barrier. Then it should work. We don't know, and we haven't got the funding to build a high pressure reactor. We're collaborating with a group in Utrecht to do that. ...If we can do that experiment and then it fails, then my confidence that this would be a suitable possible origin of life would take a serious knock.
    • 21:33
  • That's a question about the meaning of life... Why are we here? What are we doing? What's important to us? Why should we struggle to do anything, and I think most of the answers to those questions lie within society itself. ...I don't see a greater meaning, that we've been put here as a species, that we're exceptional in any way. We're just another species. We're very much similar to pretty much everything else, and I think what we've done that's good has been the achievement of society as a whole... [A] lot of people within society... humans have a need for an origins myth, and that origins myth, if it happens to bear some semblance to reality, I think a lot of people are genuinely interested to know what can we say about the origins of the Universe, about the origins of the solar system, about the origins of life. ...[C]an we as ...puny-brained humans come to, through logic, through experiments, through thinking about it, through observations, come to an explanation for how life came to be. It's a grand question. It would be wonderful to know the answer. I think a lot of people would love to know that answer, and I personally would love to know that answer, even if my own views on the subject turn out to be completely wrong.
    • 22:59
  • Yes I do think that... [viruses] are alive, not for the obvious reasons. ...I was invited to do some filming with the BBC... it was about cells, but they'd been asked to tell a story... about the viral infection of a cell, and I said, "Well I don't know anything about viruses," and they said "No, we just want to know a little bit about early evolution," and I said, "Great, I can talk about early evolution in cells, but I can't really talk about viruses." ...[T]hey said "OK, no problem," and they flew me out to Iceland to some black sand beach that I think had been used in some science fiction movie, and they said "Right, so Nick, what can you tell us about how viruses... drove the early evolution of life?" and I said, "Oh God, guys, come on!" and they said, "No, this is a film about viruses." So I had to think quickly... What I found myself saying was that viruses were parasitic on their environment and can afford to be very simple because their environment is very rich. They live inside cells. Everything that they need is provided for them, but plants are parasitic on their environment. They still need CO2. They still need water. They still need light. ...I wouldn't hesitate to call it [parasitism] a definition of life... [L]ife as a rule is parasitic on its environment, and the level of parasitism depends on the sophistication of the environment. So in that sense viruses use the richness of their local environment to make copies of themselves and they behave with the kind of low cunning that's characteristic of life. So I think of them as alive, yes.
    • 25:45
  • Protocells of some sort [lie between a hydrothermal vent system and a virus] in my mind. The trouble with viruses is that they do need a sophisticated environment to make copies of themselves. Same with selfish jumping genes, transposable elements and so on. They need to be in an environment where they can take advantage of something which is converting the environment into copies of themselves, and there's a rule... This is changing with the discovery of all these giant viruses, but as a rule you need some form of metabolism to convert the environment into copies of yourself.
  • Now it's possible to have some kind of protocell with some form of metabolism without any genetic heredity. It's possible in principle. Is it alive?
    • 28:45
  • I read some of those ideas years ago, Graham Cairns-Smith, and thought it was thrilling. Over recent years I don't really see the need for a kind of genetic intermediary between an RNA level of genetic replication and some other form of replicator. ...[T]here's no suggestion that it's there in biology. There's no suggestion that I know from geology that is capable of giving rise to more complex systems, or to having an organic takeover. It seems to add in a layer of unnecessary complexity. So I much prefer to get straight into organic chemistry, and straight into metabolism as we know it.
  • [W]hy is metabolism structured this way? There has to be thermodynamic underpinnings for it, otherwise it wouldn't happen. It had to have arisen in the absence of genes... in my mind and therefore there must be environments which are favoring protocells with this kind of metabolism, making copies of themselves... In my mind they have to get better at it, otherwise RNA is just never going to appear.
    • 29:54
  • Life as we know it has both, and the people who say genes first are in effect saying, "Well, there's plenty of nucleotides, there's plenty of RNA. The environment's providing it for free," without worrying themselves too much about what kind of an environment is going to provide all of that for free, and by definition, an environment which is effectively metabolically sophisticated enough to provide nucleotides is non-living and therefore not part of the question, so they're just pushing it aside. I would say that the whole metabolic side is needed to give rise to genetic information and nucleotides in an RNA world in the first place, that it would be a dirty RNA world contaminated with fatty acids and amino acids, and sugars and things...
  • Whether you define life as living or not is really a matter of opinion... It's a continuum. You can draw a line wherever you want or healthier not to draw a line at all... I think there has to be some form of an environment capable of giving rise to some form of proton metabolism, which is capable of giving rise to nucleotides. ...They would put me in the metabolism first camp, but I dislike the tag... because I think it's simply about... the line across a continuum...
    • 31:25
  • It's interesting... that life as a rule does not use UV radiation as an energy source, and the kind of chemistry that's being done using it doesn't resemble biochemistry as I know it... [T]he kind of environment that I'm talking about is deep sea hydrothermal vents, and the question is, "Well, does it have to be deep sea? Could it... be same systems on land?" and they exist on land. They perfectly could. So it's perfectly feasible.
    • 32:11
  • [On the Unit of selection:] It's a bit of a sterile conversation. I suppose I think of it as the cell. That's not to say that it can't act at the level of genes. Of course it can. It does all the time. Any selfish gene is acting in it's own interest. I think the trouble with looking at selection only at the level of genes is it tends to downplay the importance of genetic conflict in a strange way... [I]f you have levels of selection you can have, for example... mitochondria... They were bacteria once. They're the power packs inside eukaryotic cells... [O]nce they get inside another cell, inside another prokaryote originally, then they have an agenda of their own. They're making copies of themselves, and it's the speed at which the bacterium as a whole is making a copy of itself that means whether it tends to dominate in the population or not. It's not the individual genes. They will tend to throw away genes that they don't really need. And the host cell itself has got its agenda. It needs to make sure that it's getting benefits from this symbiont. It's not being taken over. It's not being eaten, and so it's... more intuitive to think of the interests of the cells themselves. And if you simply think of all of them as genes then you don't have that discrimination between the layers. Again, if you're thinking about protocells at the origin of life, the unit of selection in my mind is, "Can a cell make a copy of itself?" If you have a pure RNA world...
  • [Why a cell vs a gene or partial gene?] There's been plenty of work done on RNA replicators and they have a tendency to become smaller and simpler and effectively better able to make copies of themselves with whatever you provide them in the environment, and they end up with a thing called Spiegelman's Monster, which is basically the binding sequence of the RNA polymerase which allows it to furiously replicate away. ...If you're providing in the environmwent an RNA polymerase and an infinite supply of nucleotides then... they become simpler and simpler, and faster and faster at copying. ...The trouble is there isn't ever going to be an environment that's providing that for you except in a cellular context... If you're selecting at the level of genetic replication, the replicators that are better able to make copies of themselves fast are those which are, in effect, the most selfish and the least likely to cooperate to try and convert the environment into metabolism.
    • 34:50
  • The only way that you can really get a selfish replicator to be unselfish is to put it in a bag with a bunch of other selfish replicators, and then they're more or less obliged to cooperate.
  • So if you think of it from a protocell point of view, the selfish replicators which are the best at making copies of themselves are necessarily those that are best able to make the entire protocell replicate itself.
    • 36:17
  • What I would say with some degree of certainty from the example of life on earth, is that if you simply have a population of bacteria... the chances of it giving rise to the kind of morphological complexity... we see in eukariotic cells, and we do not see in bacteria, is remote... because bacteria and archaea, if you look at the amount of genetic variation, they dwarf the genetic variation that we see in Eukaryotes. They have explored genetic sequence space to orders of magnitude greater that Eukaryotes did, and despite exploring all of that space, they haven't come up with morphological complexity. ...[T]hey did through an endosymbiosis. ...It's rare between prokaryotes, rare to the point that we know of one example of free-living bacteria with bacterial cells living inside it. We know of two other examples where, there's a mealybug for example, which has inside its own cells... some gamma protein bacteria, with beta protein bacteria living inside them. It's a little bit of a strange system and it's hard to know, again, can you generalize from this, because it's all inside a Russian doll?
  • So there's one example of free living cyanobacteria... with bacteria living inside it. It wasn't phagocytosis. It's got a cell wall and it's not a phagocyte. So they can get inside, but we can say for sure it's rare. What does it do? In a nutshell it changes the topology of the cell. It allows you to internalize respiration and it's not just internalizing the membranes. It's internalizing a genetic control system with mitochondrial DNA in our own case, which by standard selection is whittled down to a kind of minimal unit required to do the job, and that in effect allows the nuclear genome to expand up to anything it wants to be. So... it's a structural change. It's not something which you can find by genetic exploration of the evolutionary space. It's something [in] which you change the topology of a cell. And once you've got that, you've got bacteria living inside another bacterial cell. You've got a fight on your hands! They've got to get along with each another somehow. So the chances of it going wrong is quite high. So I would imagine if we know of one or two examples now, there must have been thousands, millions, billions of cases of this over earth history. The fact that... all this searching across the earth that we've done for life, we find bacteria, we find archaea, we find these candidate phyla. We're not sure what they are, exactly, but they seem to be very simple and probably symbionts, and we see Eukaryotic cells, all the cases that appear to be potentially evolutionary intermediates, something slightly different, have turned out to be highly derived... from more complex ancestors.
  • I would say that if there's a probability of life being cellular, which I think there is. Life being carbon based, which I think there is. Life starting out with CO2 because it's so common in planetary atmospheres, and hydrogen, which is very common, from the kind of hydrothermal vents which I'm talking about... and liquid water. They need liquid water for serpentinization, but we know of it on Enceladus... on Europa... [Serpentinization] is giving rise to alkaline fluids with hydrogen gas. Most hydrogen gas you find in planetary atmosphere are coming from serpentinization. Olivine, which is the mineral required for that... is ubiquitous in interstellar dust... So all of this pushes you down a certain avenue, and if that's correct it gives you bacteria... and if that's correct then bacteria have a structural problem, and they're not going to get beyond bacteria except with an endosymbiosis, and that in itself is improbable, unlikely... because it only happened once, to our knowledge, on earth.
  • The plastids were acquired by a eukaryotic cell that was already a fully fledged eukaryotic cell.
    • 41:18
  • [A]cquiring mitochondria gives you a headache that can go wrong very easily, but here's an interesting problem in a nutshell. You look at a plant cell under a microscope, or an animal cell, or a fungal cell, or an amoeba or something, and you'll recognize the same structure in all of them. They've all got a nucleus. They've all got the genes as straight chromosomes. They've all got telomeres. They've all got centromeres. They've all got nuclear pore complexes. They all do mitosis as a division mechanism. They all do meiosis as two steps where you first double everything and then half it twice. They all go through the same rigmarole. They've all got mitochondria. They've all got the same membrane system, endoplasmic reticulum, things like that. ...[Y]ou could list page after page after page in a text book and it would be exactly the same for a plant, or a fungal cell, or an animal cell. Now they have really different ways of life. If you were to simply think, "Well, there's some inevitability that bacteria will give rise to complex life." ...You would imagine that a photosynthetic bacteria, a cyanobacteria would give rise directly to photosynthetic algae, eukaryotic algae, but they didn't. It was by the intermediary of acquisition of a chloroplast. There was a common ancestor of eukaryotes that was nothing like a cyanobacterium and nothing... quite like an algae except without the chloroplasts. So... why is it that we all have the same machinery inside, but we have such different lifestyles? Why don't we see multiple origins of complex life where cyanobacteria give rise to photosynthetic trees? Why don't we see predatory bacteria?
  • These are all lifestyles that exist in bacteria anyway. ...Photosynthesis obviously. The only eukaryotic lifestyle that does not exist at all in bacteria is phagocytosis... the ability to engulf other cells, to grow around them. That's never been found yet in bacteria. It seems to require... a lot of energy, a large complicated system capable of changing shape and moving around. ...For whatever reasons it never evolved. I would say the reason was that you need mitochondria to get that large and complex in the first place.
    • 41:24
  • A single discovery tomorrow could disprove everything I'm saying now. That's quite thrilling. ...We have been looking for several hundred years since Leeuwenhoek and we've not found anything really shocking that falls out of the system.
    • 44:00
  • We all share this basic machinery in cells, and it's not related to whether you're photosynthetic or whether you're phagocytes or whether you are a fungus or whether you're an animal cell. We all share the same machinery. Why? The possibility is that it's not about adaptation to the external world, it's about adaptation to these endosymbionts. These pesky bacteria that went on to become a mitochondria. Maybe this conflict of interest... [that] had to be resolved somehow was what was driving a lot the elaboration of cellular machinery. It's a kind of local... intimate conflict.
    • 44:21
  • I wouldn't expect populations of bacteria to give rise, without endosymbiosis, to complex morphology and the kind of intelligence that we have, elsewhere. I think that it would require (I'm going out on a limb here)... an endosymbiosis for the reasons I've been saying, and... that endosymbiosis is a) rare and b) likely to go wrong. So I can't put a number on how improbable it is. It's just that I would say that it's a factor that a lot of people would rather not think about. If you have an agenda where you'd like to find complex life out there, the SETI people for example... probably don't want to hear this kind of stuff. It says that it's less likely... it's not an inevitable outcome of physics.
  • I think there's plenty of solutions to Fermi's paradox, that we don't need to add this as an extra one, but yes, this would be my favorite explanation for it, that there is no inevitability about complex life, that there's nothing in the laws of cosmology that say, "[Complex] Life will start." I think that there probably is something in the laws of cosmology lending itself towards bacteria, but the idea of more complex life... I certainly wouldn't see a Simon Conway Morris view, for example, that the origin of life is so complex that you require God to put everything in motion and then convergent evolution will take you all the way to humans.
    • 46:17
  • I said you [bacteria] are not morphologically complex, you are biochemically awesome.
    • 46:58
  • [I]t's interesting to me that the bacteriophages, the viruses that you find in bacteria, are not remotely similar to the ones that you find infecting archaea, which again are not remotely similar to eukaryotic viruses. ...They're different in their appearance. They're different in their mechanisms in which they force their... I mean the bacteriophages are these classic lunar module landing things... They are stunning things to look at. ...Some Archaeal viruses look like bottle balls or postage stamps, strange shapes... They don't have any genes in common. They don't have mechanisms of entry into cells in common. They appear to be independently derived.
  • That's why they [viruses] are not in the tree of life. They don't relate in a very direct way. ...[T]he tree of life now is not only about ribosomes. You can build trees from whole genomes, but viral genomes? They don't really fit in, in a way which makes sense to people.
    • In response to the question: I can't make a phylogenetic tree of viruses?
    • 48:04
  • I've been asked on various occassions, "Why don't we, as an origins of life community, get together, think what a killer experiment is, and then go and build a CERN or something, where we go and do the experiment?" And the answer to that is... [W]e can't agree with each other about what experiment would you do? ...[I]t is intrinsically a lot more complex, precisely because it's a continuum. We don't know. We don't agree about what environment, we don't agree about what kind of chemistry or biochemistry. We can't join these things up, and so it seems to me a much healthier environment is to be deliberately multiple about it. Not to say, "Ok, this particular world view is going to dominate." I think we have to have multiple views until we know more.
    • 49:09
  • I like philosophers. I think they can teach scientists how to think very often, and... there's a lot of sloppy thinking among scientists, and I think philosophers can be quite rigorous about it. It gets a lot of scientists cross with philosophers who don't engage with science, but I think there are more philosophers these days who are engaging in a serious way with science. I think they have important things to say.
    • 50:37
  • [Martin Rees] may be right. If we were to go back 5 million years, as intelligent apes, and ask ourselves "What is postbiological life?" I think the answer is it's not a concept that would possibly mean anything. So we've had... 4 billion years of life on earth, and it's come up with an enormous wealth and variation, but it's all organic and... the chances of it coming up with humans? I can't put a number on that. ...I don't think there's an inevitability that life, once it's started will give rise to a human-like intelligence or beyond that. I think there's nothing inevitable about it, and if we just go back a few million years on earth, there was nothing inevitable about it. So I, personally would still look for organic life, but... I'm not sure that would be the easiest thing to find. It may be that it's easier to find, yes, nano aliens or something.
    • 51:23
  • It requires that life elsewhere should be modeled along similar lines to life here, which is that it should be cellular, it should be carbon-based. It should be in water. If those things are not true, then there's no reason why that numbers game would apply anywhere else. But if those things are true, then yes, I think the fact that photosynthesis only arose once, that Eucaryotes only arose once, that what Nick [Nicholas J.] Butterfield calls organ grade multicellularity, which is to say quite serious differentiation with scores of different cell types and specializations. We don't see that in fungi. We don't see that in algae. ...[Y]ou see two or three different types of cell. So that's rare. It's in plants and it's in animals. It begins to look less likely. I think it's reasonable to say it's less likely, but I wouldn't like to rely too much or put too much weight on it.
  • [On the contraversy between deep homology and convergent evolution.] [T]he classic case of convergence would be the octopus eye and the human eye, or mammalian eyes. ...The common ancestor they had had a light sensitive spot, they did have some regulatory genes in common... PAX6 for example, but that had to effectively independently recruit all the rest of the genes required to make a camera type eye, and that direction of evolutionary travel was in parallel. It was convergent. We even see in some protists... a camera-type eye in single-celled critters where there's a retina made from chloroplasts. There's a cornea made from mitochondria. There's a lens there. They don't have a brain. I don't know how they use this thing but... plainly it's a camera-type eye. ...It's a diatom of some sort. ...I would see that as a completely independent origin of a camera-type eye, albeit without a brain. I would see the octopus' and mammalian eye as being convergence in the Simon Conway Morris sense... There are certain ways that you can make an eye, that work, and all the steps along the way have to be favored, and... perhaps there are seven or eight... fundamentally different types of eye that we see on earth, and most of them have arisen more than once, always from a common ancestor, generally, that had rhodopsin as a light sensitive pigment. So you're then into an interesting terrain or... How common are the right types of light sensitive pigment? They're chemically not so straight forward.
  • I do like this quote from Simon Conway Morris that if the aliens call then don't pick up the phone. I'm not sure I'd really like to meet any of them very much. Perhaps... meeting bacteria would be the least scary... [T]he chances of meeting aliens is so remote that I haven't really troubled myself very much about it. It would be nice to think that if we did, somehow they would be a superior intelligence... they would have solved a lot of the problems of aggression and whatever else that humans have, but I fear not. I fear that it would be the opposite, that... natural selection has a knack of producing nastiness in intelligence.
    • 1:02:15
  • Does anyone care if there's an awful waste of space? It's a form of wishful thinking... We would love for the Universe to be full. ...Personally, I grew up on the Hichiker's Guide to the Universe, those kind of crazy science fiction yarns, or Star Wars or whatever it may be. The idea that the Universe is full of other intelligent beings, all kind of finding a way of getting along or having a war, but having some heroism thrown in, but... it's all human vision of ourselves thrown onto a cosmic scale. Do I believe any of it? No... Is there anything that I think, from my understanding as a biologist, that would tend to lead to that? No... Does it matter if it's a tremendous waste of space? Well, that's to say "What's the point of the Big Bang?" I don't know. The idea that the Universe may be completely empty apart from matter and energy? It would seem to be, perhaps, the default hypothesis. The fact that we find life is surprising. It would be nice if there were laws of the Universe that tended to give rise to life. Maybe there are at the level of bacteria. I don't see it at the level of large, morphologically complex beings... I think it's emotive. It's pleasing, but I doubt it's true.
    • 1:02:15
  • [M]ost of what I teach and interact with the students is more about life on earth and the principles governing evolution, and from my own point of view, the biochemical side, which is not normally part of the evolutionary biology... [I]t's relatively rare for me to discuss life elsewhere in the Universe with them.
    • 1:06:12
  • Thew problem here for me is that I'm in a biology department and astrobiology is still somewhat frowned upon by a lot of biologists who would see it as a form of speculation. So the courses that I teach are about life on earth and they're not so much about life in the Universe... [I]t is something that I should develop, I think.
    • 1:06:48
  • There are people at UCL, Ian Crawford, who's doing a great deal for astrobiology, but it's not something which is happening through my department. It's happening through Planetary sciences. It's not happening in biological sciences...
    • 1:07:28
  • I've had long and sometimes difficult discussions, especially about the singularity of the origin of Eukaryotes... A lot of people don't like that. ...[I]t's not really about what does it say about the probability of life elsewhere, although it has things to say to that. It's really about life on earth, and a lot of people are very uncomfortable with the idea of improbability... I've had quite difficult discussions with some students about that, but rarely... about life elsewhere in the Universe.
    • 1:07:48
  • I see myself as a biologist or a biochemist, but... in the context of astrobiology as a broader subject, it forces me to wrestle with physics, with cosmology, with chemistry, with geology, with earth sciences or planetary sciences, and that's a thrill. ...I think it's what most people are drawn into science in the first place for, because science, in its biggest sense, is what inspires people, and by the time that you've got to the level of doing a PhD, it's narrowed down so much that a lot of people are almost forced to lose their imagination, and their creativity as a scientist... I think astrobiology is a subject that puts all that back in, in heaps.
  • No, we're not alone [in the universe]. We share it with lots of friendly bacteria [and this includes bacteria on other planets].
    • 1:09:30

Transformer (2022)

[edit]
: The Deep Chemistry of Life and Death
  • For decades, biology has been dominated by information—the power of genes. ...[Y]et there is no difference in the information content of a living protozoon and one that died ...The difference between alive and dead lies in energy flow ...the ability of cells to continually regenerate themselves from simpler building blocks.
  • Even the laws of thermodynamics... can be recast in terms of information — Shannon entropy, the laws of bits of information. But this view generates its own paradox at the origin of life. ...Place information at the heart of life, and there is a problem with the emergence of function ...the origin of biological information. There are problems... in understanding why we age and die... diseases... and how experiences can give rise to conscious mind. ...A far better question ...what processes animate cells and set them apart from inanimate matter?
  • It is the movement that creates the form.
  • Flux is a form of flow, but with one crucial difference. ...In biochemistry flux is the flow of things that are transformed along the way.
  • [M]etabolic flux... Even a simple bacterial cell can undergo... a billion trnasformations per second... Metabolism is... what being alive is.
  • Biochemistry became the study of how... simple molecules were interconnected one into another. ...The [simple] molecules ...containing ...up to about twenty carbons, but most ...have fewer than ten.
  • [B]iochemical pathways that produce the basic building blocks of life are... conserved across practically all cells.
  • The double helix of DNA... is composed of two long chains [of 'letters'] that snake around each other... each strand providing an exact template for the other. ...[E]ach strand ...contains just four types of letter, with ...billions ...arranged down... the chain. ...3,000 million letters ...make up the human genome ...[T]he same gene — the same lines of code — can have different effects depending on the context.
  • If the Krebs cycle is ordained by thermodynamics, then it should take place spontaneously in some suitably propitious envirnonment, even in the absence of genes.
  • The inner logic of metabolism... Much of it is imposed by thermodynamics; some is facilitated by catalysts. Some is refined by genes. And part stems from the vicissitudes of life itself, which forced evolution down improbable paths, while transforming our geologically restless globe from a sterile, anoxic planet into the living, high-octane world of today.

Quotes about Lane

[edit]
  • In Transformer, Lane indulges in a great many of the banes of popular science writing... These kinds of over-earnest attempts to defang a complicated subject are an enduring mystery; the people who need them won't read the book, and the people who'll read the book don't need them. ...Fortunately, Lane’s discussion ...is itself very winningly animated, and that saves it ...Lane’s personal excitement ...goes a long way toward making ...biochemistry comprehensible ...[T]his is done through personalities; Transformer is as much about the people investigating the Krebs cycle as it is about the cycle ...That kind of personality pervades the book and makes it ...consistently fascinating reading.
  • I read a book called The Vital Question. ...A few months later... I had also ordered Nick’s three other books, read two of them, and arranged to meet him in New York City. ...He is one of those original thinkers who makes you say: More people should know about this guy’s work. ...Nick is talking about how getting energy right at the cellular level explains how life began, and how it got so complex. ...I'm intrigued by the practical applications of Nick’s work. Mitochondria could play a role in diseases like cancer. ...[O]ur foundation’s global health team is talking to Nick about the potential implications for the fight against malnutrition. ...[T]here’s no telling whether his specific arguments will turn out to be right. But even if they don’t, I suspect his focus on energy will be seen as an important contribution to our understanding of where we come from, and where are we going.

See also

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[edit]
Wikipedia
Wikipedia
Wikipedia has an article about:
  • Nick-Lane.net
  • Prof Nick Lane Professor of Evolutionary Biochemistry, University College London (UCL) Div of Biosciences; Genetics, Evolution & Environment.
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