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Nick Lane: Origin of Life, Evolution, Aliens, Biology, and Consciousness | Lex Fridman Podcast #318


small model | large model

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Well, the source of energy at the origin of life
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is the reaction between carbon dioxide and hydrogen.
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And amazingly, most of these reactions are exergonic,
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which is to say they release energy.
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If you have hydrogen and CO2,
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and you put them together in a falcon tube
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and you warm it up to say 50 degrees centigrade,
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and you put in a couple of catalysts and you shake it,
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nothing's gonna happen.
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But thermodynamically, that is less stable.
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Two gases, hydrogen and CO2, is less stable than cells.
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What should happen is you get cells coming out.
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Why doesn't that happen?
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It's because of the kinetic barriers.
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That's where you need the spark.
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The following is a conversation with Nick Lane,
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a biochemist at University College London
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and author of some of my favorite books
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on biology, science, and life ever written,
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including his two most recent titled
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"'Transformer,' The Deep Chemistry of Life and Death,"
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and the vital question, why is life the way it is?
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This is the Lex Friedman podcast.
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To support it, please check out our sponsors
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in the description.
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And now, dear friends, here's Nick Lane.
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Let's start with perhaps the most mysterious,
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the most interesting question that we little humans
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can ask of ourselves.
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How did life originate on Earth?
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You could ask anybody working on the subject,
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and you'll get a different answer from all of them.
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They will be pretty passionately held opinions,
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and their opinions grounded in science,
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but they're still really, at this point, their opinions,
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because there's so much stuff to know
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that all we can ever do is get a small slice of it,
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and it's the context which matters.
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So I can give you my answer.
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My answer is from a biologist's point of view.
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That has been missing from the equation over decades,
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which is, well, what does life do on Earth?
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Why is it this way?
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Why is it made of cells?
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Why is it made of carbon?
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Why is it powered by electrical charges on membranes?
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There's all these interesting questions about cells
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that if you then look to see,
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well, is there an environment on Earth,
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on the early Earth four billion years ago,
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that kind of matches the requirements of cells?
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Well, there is one.
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There's a very obvious one.
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It's basically created by whenever you have
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a wet, rocky planet, you get these hydrothermal vents,
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which generate hydrogen gas in bucket loads,
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and electrical charges on kind of cell like pores
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that can drive the kind of chemistry that life does.
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So it seems so beautiful and so obvious
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that I've spent the last 10 years or more
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trying to do experiments.
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It turns out to be difficult, of course.
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Everything's more difficult than you ever thought
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it was gonna be, but it looks, I would say,
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more true rather than less true over that 10 year period.
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I think I have to take a step back every now and then
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and think, hang on a minute, where's this going?
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I'm happy it's going in a sensible direction.
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And I think then you have these other interesting dilemmas.
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I mean, I'm often accused of being too focused
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on life on Earth, too kind of narrow minded
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and inward looking, you might say.
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I'm talking about carbon, I'm talking about cells,
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and maybe you or plenty of people can say to me,
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ah, yeah, but life can be anything.
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I have no imagination.
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And maybe they're right.
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But unless we can say why life here is this way,
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and if those reasons are fundamental reasons,
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or if they're just trivial reasons,
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then we can't answer that question.
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So I think they're fundamental reasons,
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and I think we need to worry about them.
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Yeah, there might be some deep truth to the puzzle
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here on Earth that will resonate
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with other puzzles elsewhere that will,
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solving this particular puzzle
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will give us that deeper truth.
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So what, to this puzzle, you said vents, hydrogen,
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wet, so chemically, what is the potion here?
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How important is oxygen?
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You wrote a book about this.
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Yeah, and I actually just came straight here
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from a conference where I was chairing a session
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on whether oxygen matters or not in the history of life.
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Of course it matters, but it matters most
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to the origin of life to be not there.
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As I see it, we have this, I mean,
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life is made of carbon, basically, primarily,
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organic molecules with carbon, carbon bonds.
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And the building block, the Lego brick
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that we take out of the air or take out of the oceans
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is carbon dioxide.
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And to turn carbon dioxide into organic molecules,
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we need to strap on hydrogen.
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And so we need, and this is basically
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what life is doing, it's hydrogenating carbon dioxide.
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It's taking the hydrogen, the bubbles out of the earth
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in these hydrothermal vents, and it sticks it on CO2.
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And it's kind of really as simple as that.
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And actually, thermodynamically,
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there's the thing that I find most troubling
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is that if you do these experiments in the lab,
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the molecules you get are exactly the molecules
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that we see at the heart of biochemistry
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in the heart of life.
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Is there something to be said about the earliest origins
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of that little potion, that chemical process?
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What really is the spark there?
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There isn't a spark.
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There is a continuous chemical reaction.
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And there is kind of a spark,
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but it's a continuous electrical charge
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which helps drive that reaction.
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There's a literally spark.
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Well, the charge at least, but yes.
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I mean, a spark in that sense is,
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we tend to think of in terms of Frankenstein,
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we tend to think in terms of electricity
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and one moment you zap something and it comes alive.
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And what does that really mean?
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It's come alive and now what's sustaining it?
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Well, we are sustained by oxygen,
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by this continuous chemical reaction.
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And if you put a plastic bag on your head,
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then you've got a minute or something before it's all over.
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So some way of being able to leverage a source of energy.
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Well, the source of energy at the origin of life
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is the reaction between carbon dioxide and hydrogen.
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And amazingly, most of these reactions are exergonic,
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which is to say they release energy.
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If you have hydrogen and CO2
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and you put them together in a falcon tube
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and you warm it up to say 50 degrees centigrade
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and you put in a couple of catalysts and you shake it,
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nothing's gonna happen.
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But thermodynamically, that is less stable.
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Two gases, hydrogen and CO2, is less stable than cells.
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What should happen is you get cells coming out.
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So why doesn't that happen?
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It's because of the kinetic barriers.
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That's where you need the spark.
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Is it possible that life originated
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multiple times on Earth?
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The way you describe it, you make it sound so easy.
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There's a long distance to go from the first bits
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of prebiotic chemistry to, say, molecular machines
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like ribosomes.
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Is that the first thing that you would say is life?
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Like if I introduce you, the two of you at a party,
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you would say that's a living thing?
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I would say as soon as we introduce genes, information,
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into systems that are growing anyway,
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so I would talk about growing protocells,
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as soon as we introduce even random bits of information
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into there, I'm thinking about RNA molecules, for example,
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doesn't have to have any information in it.
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It can be a completely random sequence.
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But if it's introduced into a system which is in any case
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growing and doubling itself and reproducing itself,
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then any changes in that sequence that allow it
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to do so better or worse are now selected
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by perfectly normal natural selection.
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But it's a system.
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So that's when it becomes alive to my mind.
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That's encompassed into like an object
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that keeps information and evolves that information
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over time or changes that information over time
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in response to the.
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So it's always part of a cell system
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from the very beginning.
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So is your sense that it started only once
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because it's difficult or is it possibly started
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in multiple locations on Earth?
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It's possible it started multiple occasions.
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There's two provisos to that.
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One of them is oxygen makes it impossible really
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for life to start.
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So as soon as we've got oxygen in the atmosphere,
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then life isn't gonna keep starting over.
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So I often get asked by people,
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why can't we have life starting?
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If it's so easy, why can't life start in these vents now?
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And the answer is if you want hydrogen to react with CO2
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and there's oxygen there, hydrogen reacts
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with oxygen instead.
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It's just, you get an explosive reaction that way.
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It's rocket fuel.
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So it's never gonna happen.
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But for the origin of life earlier than that,
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all we know is that there's a single common ancestor
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for all of life.
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There could have been multiple origins
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and they all just disappeared.
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But there's a very interesting deep split in life
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between bacteria and what are called archaea,
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which look just the same as bacteria.
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And they're not quite as diverse, but nearly.
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And they are very different in their biochemistry.
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And so any explanation for the origin of life
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has to account as well for why they're so different
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and yet so similar.
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And that makes me think that life probably
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did arise only once.
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Can you describe the difference that's interesting there?
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Well, how they're similar, how they're different?
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Well, they're different in their membranes primarily.
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They're different in things like DNA replication.
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They use completely different enzymes
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and the genes behind it for replicating DNA.
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So they both have membranes, both have DNA replication.
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Yes.
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The process of that is different.
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They both have DNA.
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The genetic code is identical in them both.
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The way in which it's transcribed into RNA,
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into the copy of a gene,
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and the way that that's then translated into a protein,
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that's all basically the same in both of these groups.
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So they clearly share a common ancestor.
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It's just that they're different
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in fundamental ways as well.
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And if you think about, well,
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what kind of processes could drive that divergence
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very early on?
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I can think about it in terms of membranes,
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in terms of the electrical charges on membranes.
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And it's that that makes me think that there was probably,
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there were probably many unsuccessful attempts
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but only one really successful attempt.
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Can you explain why that divergence
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makes you think there's one common ancestor?
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Okay, can you describe that intuition?
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I'm a little bit unclear about why the divert,
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like the leap from the divergence means there's one.
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Do you mean like the divergence indicates
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that there was a big invention at that time from one source?
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If you'd got, as I imagine it,
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you have a common ancestor living in a hydrothermal vent.
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Let's say there are millions of vents
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and millions of potential common ancestors
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living in all of those vents,
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but only one of them makes it out first.
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Then you could imagine that that cell
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is then gonna kind of take over the world
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and wipe out everything else.
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And so what you would see would be
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a single common ancestor for all of life.
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But with lots of different vent systems
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all kind of vying to create the first life forms,
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you might say.
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So this thing is a cell, a single cell organism.
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We're always talking about populations of cells, but yes.
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These are single celled organisms.
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But the fundamental life form is a single cell, right?
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So like, or, so they're always together
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but they're alone together.
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Yeah.
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There's a machinery in each one individual component
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that if left by itself would still work, right?
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Yes, yes, yes.
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It's the unit of selection is a single cell.
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But selection operates over generations
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and changes over generations in populations of cells.
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So it would be impossible to say that a cell
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is the unit of selection in the sense that
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unless you have a population, you can't evolve,
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you can't change.
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Right, but there was one Chuck Norris,
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it's an American reference cell
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that made it out of the vents, right?
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Or like the first one.
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So imagine then that there's one cell gets out
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and it takes over the world.
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It gets out in the water, it's like floating around.
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We're deep in the ocean somewhere.
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Yeah.
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But actually two cells got out
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and they appear to have got out from the same vent
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because they both share the same code and everything else.
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So unless all the, you know,
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we've got a million different common ancestors
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in all these different vents.
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So either they all have the same code
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and two cells spontaneously merge from different places
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or two different cells, fundamentally different cells
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came from the same place.
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So either way, what are the constraints that say,
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not just one came out or not half a million came out,
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but two came out.
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That's kind of a bit strange.
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So how did they come out?
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Well, they come out because what are you doing inside a vent
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is you're relying on the electrical charges down there
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to power this reaction between hydrogen and CO2
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to make yourself grow.
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And when you leave the vent, you've got to do that yourself.
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You've got to power up your own membrane.
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And so the question is,
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well, how do you power up your own membrane?
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And the answer is, well, you need to pump.
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You need to pump ions to give an electrical charge
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on the membrane.
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So what do the pumps look like?
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Well, the pumps look different in these two groups.
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It's as if they both emerged from a common ancestor.
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As soon as you've got that ancestor,
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things move very quickly and divergently.
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Why does the DNA replication look different?
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Well, it's joined to the membrane.
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The membranes are different.
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The DNA replication is different
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because it's joined to a different kind of membrane.
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So there's interesting, this is detail, you may say,
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but it's also fundamental
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because it's about the two big divergent groups
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of life on Earth that seem to have diverged really early on.
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And it all started from one organism.
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And then that organism just start replicating
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the heck out of itself with some mutation of the DNA.
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So like there's some, there's a competition
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through the process of evolution.
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They're not like trying to beat each other up.
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They're just, they're just trying to live.
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Just replicate us.
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Yeah.
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Well, you know, let's not minimize there.
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Yeah.
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They're just trying to chill.
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They're trying to relax up.
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There's no, but there's no sense of trying to survive.
link |
00:14:35.120
They're replicating.
link |
00:14:36.440
I mean, there's no sense
link |
00:14:37.360
in which they're trying to do anything.
link |
00:14:39.600
They're just kind of an outgrowth of the Earth,
link |
00:14:42.000
you might say.
link |
00:14:42.840
Of course, the aliens would describe us humans
link |
00:14:44.760
in that same way.
link |
00:14:45.680
They might be right.
link |
00:14:47.280
This primitive life.
link |
00:14:48.640
It's just ants that are hairless,
link |
00:14:52.440
mostly hairless.
link |
00:14:53.360
Overgrown ants.
link |
00:14:54.360
Overgrown ants.
link |
00:14:55.600
Okay.
link |
00:14:56.800
What do you think about the idea of panspermia
link |
00:14:59.360
that the theory that life did not originate on Earth
link |
00:15:03.400
and was planted here from outer space?
link |
00:15:06.880
Or pseudopanspermia, which is like the basic ingredients,
link |
00:15:10.640
the magic that you mentioned was planted here
link |
00:15:12.920
from elsewhere in space?
link |
00:15:14.680
I don't find them helpful.
link |
00:15:16.360
That's not to say they're wrong.
link |
00:15:18.800
So, pseudotranspermia, the idea that the chemicals,
link |
00:15:22.320
the amino acids, the nucleotides
link |
00:15:23.880
are being delivered from space.
link |
00:15:24.800
Well, we know that happens.
link |
00:15:25.800
It's unequivocal.
link |
00:15:27.080
They're delivered on meteorites, comets, and so on.
link |
00:15:30.840
So what do they do next?
link |
00:15:31.800
That's, to me, the question.
link |
00:15:33.120
Well, what do they do is they stock a soup.
link |
00:15:35.120
Presumably, they land in a pond or in an ocean
link |
00:15:37.440
or wherever they land.
link |
00:15:39.000
And then you end up with a best possible case scenario
link |
00:15:42.120
is you end up with a soup of nucleotides
link |
00:15:43.880
and amino acids.
link |
00:15:44.720
And then you have to say, so now what happens?
link |
00:15:46.400
And the answer is, oh, well, they have to go,
link |
00:15:48.200
bloop, become alive.
link |
00:15:50.760
So how did they do that?
link |
00:15:51.720
And you may as well say then a miracle happened.
link |
00:15:54.720
I don't believe in soup.
link |
00:15:57.080
I think what we have in event is a continuous conversion,
link |
00:16:00.680
a continuous growth, a continuous reaction,
link |
00:16:02.680
a continuous converting a flow of molecules
link |
00:16:05.880
into more of yourself, you might say,
link |
00:16:07.880
even if it's a small bit.
link |
00:16:08.840
So you've got a kind of continuous self organization
link |
00:16:13.000
and growth from the very beginning.
link |
00:16:14.760
You never have that in a soup.
link |
00:16:17.000
Isn't the entire universe and living organisms
link |
00:16:20.440
in the universe, isn't it just soup all the way down?
link |
00:16:25.000
Isn't it all soup?
link |
00:16:25.840
No, no, I mean, soup almost by definition
link |
00:16:27.760
doesn't have a structure.
link |
00:16:29.560
But soup is a collection of ingredients
link |
00:16:32.200
that are like randomly interacting.
link |
00:16:34.040
Yeah, but they're not random.
link |
00:16:36.200
They're not, I mean, we have chemistry going on here.
link |
00:16:38.760
We have metal grains forming, which are, you know,
link |
00:16:41.160
effective oil water interactions.
link |
00:16:43.400
Okay, so it feels like there's a direction to a process,
link |
00:16:45.960
like a directed process.
link |
00:16:47.400
There are directions to processes, yeah.
link |
00:16:49.920
And if you're starting with CO2
link |
00:16:52.640
and you've got two reactive fluids being brought together
link |
00:16:55.600
and they react, what are they gonna make?
link |
00:16:57.720
Well, they make carboxylic acids,
link |
00:16:59.880
which include the fatty acids
link |
00:17:01.720
that make up the cell membranes.
link |
00:17:03.040
And they form directly into bilayer membranes.
link |
00:17:06.520
They form like soap bubbles.
link |
00:17:07.720
It's spontaneous organization caused by the nature
link |
00:17:11.240
of the molecules.
link |
00:17:12.080
And those things are capable of growing
link |
00:17:14.040
and are capable in effect of being selected
link |
00:17:16.440
even before there are genes.
link |
00:17:18.320
We have this, so we have a lot of order
link |
00:17:20.080
and that order is coming from thermodynamics.
link |
00:17:22.560
And the thermodynamics is always about increasing
link |
00:17:25.400
the entropy of the universe.
link |
00:17:27.040
But if you have oil and water and they're separating,
link |
00:17:30.480
you're increasing the entropy of the universe,
link |
00:17:32.040
even though you've got some order,
link |
00:17:33.160
which is the soap and the water are not missable.
link |
00:17:36.520
Now, to come back to your first question
link |
00:17:39.480
about panspermia properly,
link |
00:17:43.840
that just pushes the question somewhere else.
link |
00:17:45.440
That just, even if it's true,
link |
00:17:46.840
maybe life did start on Earth by panspermia.
link |
00:17:49.680
So what are the principles
link |
00:17:52.200
that govern the emergence of life on any planet?
link |
00:17:55.200
It's an assumption that life started here.
link |
00:17:57.560
And it's an assumption that it started
link |
00:18:01.000
in a hydrothermal vent or it started
link |
00:18:02.760
in a terrestrial geothermal system.
link |
00:18:04.680
The question is, can we work out a testable sequence
link |
00:18:07.560
of events that would lead from one to the other one
link |
00:18:10.440
and then test it and see if there's any truth in it or not?
link |
00:18:12.640
With panspermia, you can't do any of that.
link |
00:18:14.880
But the fundamental question of panspermia is,
link |
00:18:17.680
do we have the machine here on Earth to build life?
link |
00:18:23.040
Is the vents enough?
link |
00:18:25.680
Is oxygen and hydrogen and whatever the heck else we want
link |
00:18:31.720
and some source of energy and heat,
link |
00:18:34.520
is that enough to build life?
link |
00:18:36.320
Yes.
link |
00:18:37.280
Well, that's, of course you would say that as a human.
link |
00:18:41.480
Yeah.
link |
00:18:42.800
But there could be aliens right now
link |
00:18:44.640
chuckling at that idea.
link |
00:18:46.160
Maybe you need some special sauce,
link |
00:18:50.600
special elsewhere sauce.
link |
00:18:52.040
So your sense is we have everything here.
link |
00:18:54.600
I mean, this is precisely the question.
link |
00:18:57.280
I like to, when I'm talking in schools,
link |
00:18:59.600
I like to start out with the idea
link |
00:19:00.800
of we can make a time machine.
link |
00:19:03.240
We go back four billion years
link |
00:19:05.120
and we go to these environments that people talk about.
link |
00:19:07.400
We go to a deep sea hydrothermal vent,
link |
00:19:09.280
we go to a kind of Yellowstone Park type place environment
link |
00:19:14.120
and we find some slime that looks like we can test it.
link |
00:19:18.560
It's made of organic molecules.
link |
00:19:20.240
It's got a structure which is not obviously cells,
link |
00:19:22.400
but you know, is this a stepping stone
link |
00:19:25.640
on the way to life or not?
link |
00:19:26.880
Yeah.
link |
00:19:27.720
How do we know?
link |
00:19:29.080
Unless we've got an intellectual framework
link |
00:19:31.600
that says this is a stepping stone and that's not a step.
link |
00:19:34.200
You know, we'd never know.
link |
00:19:35.040
We wouldn't know which environment to go to,
link |
00:19:36.520
what to look for, how to say this.
link |
00:19:38.560
So all we can ever hope for,
link |
00:19:39.920
because we're never gonna build that time machine,
link |
00:19:41.880
is to have an intellectual framework
link |
00:19:43.440
that can explain step by step, experiment by experiment,
link |
00:19:46.880
how we go from a sterile inorganic planet
link |
00:19:49.680
to living cells as we know them.
link |
00:19:52.480
And in that framework, every time you have a choice,
link |
00:19:55.280
it could be this way or it could be that way,
link |
00:19:57.000
or there's lots of possible forks down that road.
link |
00:20:02.320
Did it have to be that way?
link |
00:20:03.640
Could it have been the other way?
link |
00:20:05.240
And would that have given you life
link |
00:20:06.560
with very different properties?
link |
00:20:08.840
And so if you come up with a, you know,
link |
00:20:11.080
it's a long hypothesis, because as I say,
link |
00:20:12.720
we're going from really simple prebiotic chemistry
link |
00:20:15.560
all the way through to genes and molecular machines.
link |
00:20:17.840
That's a long, long pathway.
link |
00:20:20.160
And nobody in the field would agree on the order
link |
00:20:22.320
in which these things happened,
link |
00:20:23.760
which is not a bad thing,
link |
00:20:24.600
because it means that you have to go out
link |
00:20:25.800
and do some experiments and try and demonstrate
link |
00:20:27.840
that it's possible or not possible.
link |
00:20:29.840
It's so freaking amazing that it happened though.
link |
00:20:37.440
It feels like there's a direction to the thing.
link |
00:20:41.920
Can you try to answer from a framework perspective
link |
00:20:47.600
of what is life?
link |
00:20:49.640
So you said there's some order and yet there's complexity.
link |
00:20:57.240
So it's not perfectly ordered.
link |
00:20:59.160
It's not boring.
link |
00:21:00.360
There's still some fun in it.
link |
00:21:02.040
And it also feels like the processes have a direction
link |
00:21:06.280
through the selection mechanism.
link |
00:21:07.920
They seem to be building something,
link |
00:21:10.640
always better, always improving.
link |
00:21:14.280
I mean, maybe it's...
link |
00:21:15.120
I mean, that's a perception.
link |
00:21:16.280
That's our romanticization of things are always better.
link |
00:21:20.720
Things are getting better, we'd like to believe that.
link |
00:21:22.920
I mean, you think about the world
link |
00:21:24.120
from the point of view of bacteria
link |
00:21:25.680
and bacteria are the first things to emerge
link |
00:21:28.000
from whatever environment they came from.
link |
00:21:30.080
And they dominated the planet very, very quickly.
link |
00:21:32.760
And they haven't really changed.
link |
00:21:34.480
Four billion years later, they look exactly the same.
link |
00:21:36.680
So about four billion years ago,
link |
00:21:38.800
bacteria started to really run the show.
link |
00:21:42.440
And then nothing happened for a while.
link |
00:21:44.720
Nothing happened for two billion years.
link |
00:21:47.000
Then after two billion years,
link |
00:21:48.160
we see another single event origin, if you like,
link |
00:21:51.440
of our own type of cell, the eukaryotic cells.
link |
00:21:53.960
So cells with a nucleus and lots of stuff going on inside.
link |
00:21:57.280
Another singular origin.
link |
00:21:58.480
It only happened once in the history of life on earth.
link |
00:22:01.120
Maybe it happened multiple times and there's no evidence.
link |
00:22:03.360
Everything just disappeared,
link |
00:22:04.360
but we have to at least take it seriously
link |
00:22:07.520
that there's something that stops bacteria
link |
00:22:10.040
from becoming more complex because they didn't.
link |
00:22:13.600
That's a fact that they emerged four billion years ago.
link |
00:22:17.520
And something happened two billion years ago,
link |
00:22:19.400
but the bacteria themselves didn't change.
link |
00:22:21.320
They remain bacterial.
link |
00:22:22.560
So there is no trajectory, necessary trajectory
link |
00:22:26.120
towards great complexity in human beings at the end of it.
link |
00:22:28.640
It's very easy to imagine that without photosynthesis
link |
00:22:31.360
arising or without eukaryotes arising,
link |
00:22:33.060
that a planet could be full of bacteria and nothing else.
link |
00:22:36.400
We'll get to that because that's a brilliant invention.
link |
00:22:39.360
And there's a few brilliant invention along the way.
link |
00:22:41.560
But what is life?
link |
00:22:44.040
If you were to show up on earth,
link |
00:22:46.000
but to take that time machine,
link |
00:22:47.840
and you said, asking yourself the question,
link |
00:22:50.300
is this a stepping stone towards life?
link |
00:22:52.760
As you step along, when you see the early bacteria,
link |
00:22:57.040
how would you know it's life?
link |
00:22:59.640
And then this is really important question
link |
00:23:01.800
when you go to other planets and look for life.
link |
00:23:04.640
Like what is the framework of telling a difference
link |
00:23:08.280
between a rock and a bacteria?
link |
00:23:12.280
I mean, the question's kind of both impossible to answer
link |
00:23:15.280
and trivial at the same time.
link |
00:23:16.540
And I don't like to answer it
link |
00:23:18.140
because I don't think there is an answer.
link |
00:23:19.680
I think we're trying to describe the process of time.
link |
00:23:22.080
Those are the most fun questions.
link |
00:23:22.920
What do you mean there's no answer?
link |
00:23:23.760
No, there is no answer.
link |
00:23:24.580
I mean, there's lots of,
link |
00:23:25.420
there are at least 40 or 50 different definitions
link |
00:23:27.860
of life out there.
link |
00:23:29.000
And most of them are, well, obviously bad
link |
00:23:33.040
in one way or another.
link |
00:23:34.080
I mean, there's freaks.
link |
00:23:37.120
I can never remember the exact words that people use,
link |
00:23:39.920
but there's a NASA working definition of life,
link |
00:23:43.720
which more or less says a system,
link |
00:23:46.000
which is capable of self sustaining system,
link |
00:23:49.560
capable of evolution or something along those lines.
link |
00:23:52.680
And I immediately have a problem
link |
00:23:54.600
with the word self sustaining
link |
00:23:56.200
because it's sustained by the environment.
link |
00:23:58.240
And I know what they're getting at.
link |
00:24:00.120
I know what they're trying to say,
link |
00:24:01.000
but I pick a hole in that.
link |
00:24:03.120
And there's always wags who say,
link |
00:24:04.720
but you know, by that definition, a rabbit is not alive.
link |
00:24:07.360
Only a pair of rabbits would be alive
link |
00:24:09.800
because a single rabbit is incapable of copying itself.
link |
00:24:12.880
There's all kinds of pedantic, silly,
link |
00:24:16.080
but also important objections to any hypothesis.
link |
00:24:19.280
The real question is what is, you know,
link |
00:24:22.280
we can argue all day or people do argue all day
link |
00:24:24.920
about is a virus alive or not?
link |
00:24:27.440
And it depends on the content.
link |
00:24:29.120
Most biologists could not agree about that.
link |
00:24:31.360
So then what about a jumping gene,
link |
00:24:32.720
a retro element or something that is even simpler
link |
00:24:34.920
than a virus, but it's capable of converting
link |
00:24:39.600
its environment into a copy of itself.
link |
00:24:42.920
And that's about as close, this is not a definition,
link |
00:24:45.200
but this is a kind of a description of life
link |
00:24:47.440
is that it's able to parasitize the environment.
link |
00:24:52.080
And that goes for plants as well as animals
link |
00:24:53.920
and bacteria and viruses to make a relatively exact copy
link |
00:24:58.920
of themselves, informationally exact copy of themselves.
link |
00:25:04.120
By the way, it doesn't really have to be
link |
00:25:06.160
a copy of itself, right?
link |
00:25:07.680
It just has to be, you have to create something
link |
00:25:11.480
that's interesting, the way evolution is.
link |
00:25:16.400
So it is extremely powerful process of evolution,
link |
00:25:19.920
which is basically make a copy of yourself
link |
00:25:22.360
and sometimes mess up a little bit.
link |
00:25:25.080
That seems to work really well.
link |
00:25:26.440
I wonder if it's possible to mess up big time
link |
00:25:30.360
as a standard, as a default.
link |
00:25:32.360
It's called a hopeful monster and in principle it can.
link |
00:25:36.880
Actually, it turns out, I would say that this is due
link |
00:25:40.520
a reemergence, this is some amazing work
link |
00:25:43.200
from Michael Levin, I don't know if you came across him,
link |
00:25:45.320
but if you haven't interviewed him,
link |
00:25:47.360
you should interview him about, yeah.
link |
00:25:50.800
I'm talking to him in a few days.
link |
00:25:53.640
Oh, fantastic.
link |
00:25:54.480
So I mentioned, there's two people that Andre,
link |
00:25:59.320
if I may mention, Andre Kapathe is a friend
link |
00:26:02.360
who's really admired in the AI community,
link |
00:26:04.600
said you absolutely must talk to Michael and to Nick.
link |
00:26:09.680
So of course, I'm a huge fan of yours,
link |
00:26:11.800
so I'm really fortunate that we can actually
link |
00:26:14.120
make this happen.
link |
00:26:14.960
Anyway, you were saying?
link |
00:26:16.080
Well, Michael Levin is doing amazing work,
link |
00:26:19.280
basically about the way in which electrical fields
link |
00:26:22.160
control development and he's done some work
link |
00:26:25.640
with planarian worms, so flat worms,
link |
00:26:27.880
where he'll tell you all about this,
link |
00:26:29.400
so I won't say any more than the minimum,
link |
00:26:30.800
but basically you can cut their head off
link |
00:26:32.440
and they'll redevelop a different, a new head.
link |
00:26:35.640
But the head that they develop depends,
link |
00:26:37.680
if you knock out just one iron pump in a membrane,
link |
00:26:42.520
so you change the electrical circuitry just a little bit,
link |
00:26:45.240
you can come up with a completely different head.
link |
00:26:47.000
It can be a head which is similar to those
link |
00:26:49.600
that diverged 150 million years ago
link |
00:26:52.080
or it can be a head which no one's ever seen before,
link |
00:26:54.200
a different kind of head.
link |
00:26:56.760
Now that is really, you might say, a hopeful monster.
link |
00:26:59.320
This is a kind of leap into a different direction.
link |
00:27:02.000
The only question for natural selection is does it work?
link |
00:27:05.040
Is the change itself feasible as a single change?
link |
00:27:08.200
And the answer is yes, it's just a small change
link |
00:27:09.880
to a single gene.
link |
00:27:11.080
And the second thing is it gives rise
link |
00:27:12.900
to a completely different morphology.
link |
00:27:14.880
Does it work?
link |
00:27:16.000
And if it works, that can easily be a shift.
link |
00:27:21.000
But for it to be a speciation, for it to continue,
link |
00:27:25.400
for it to give rise to a different morphology over time,
link |
00:27:29.720
then it has to be perpetuated.
link |
00:27:32.000
So that shift, that change in that one gene
link |
00:27:37.200
has to work well enough that it is selected and it goes on.
link |
00:27:41.100
And copied enough times to where you can really test it.
link |
00:27:44.320
So the likelihood, it would be lost,
link |
00:27:46.040
but there will be some occasions where it survives.
link |
00:27:48.780
And yes, the idea that we can have sudden, fairly abrupt
link |
00:27:51.920
changes in evolution, I think it's time for a rebirth.
link |
00:27:54.940
What about this idea that kind of trying to
link |
00:27:58.640
mathematize a definition of life and saying how many steps,
link |
00:28:04.500
the shortest amount of steps it takes to build the thing,
link |
00:28:07.100
almost like an engineering view of it?
link |
00:28:09.660
Ah, I like that view.
link |
00:28:11.880
Because I think that in a sense, that's not very far away
link |
00:28:14.560
from what a hypothesis needs to do
link |
00:28:17.340
to be a testable hypothesis for the origin of life.
link |
00:28:19.520
You need to spell out, here's each step,
link |
00:28:22.440
and here's the experiment to do for each step.
link |
00:28:24.960
The idea that we can do it in the lab,
link |
00:28:26.960
some people say, oh, we'll have created life
link |
00:28:29.820
within five years, but ask them what they mean by life.
link |
00:28:34.560
We have a planet four billion years ago
link |
00:28:36.680
with these vent systems across the entire surface
link |
00:28:39.280
of the planet, and we have millions of years if we wanted.
link |
00:28:41.880
I have a feeling that we're not talking about
link |
00:28:43.400
millions of years.
link |
00:28:44.240
I have a feeling we're talking about maybe millions
link |
00:28:47.880
of nanoseconds or picoseconds.
link |
00:28:49.520
We're talking about chemistry, which is happening quickly.
link |
00:28:53.880
But we still need to constrain those steps,
link |
00:28:56.780
but we've got a planet doing similar chemistry.
link |
00:29:00.880
You asked about a trajectory.
link |
00:29:02.660
The trajectory is the planetary trajectory.
link |
00:29:05.260
The planet has properties.
link |
00:29:06.760
Basically, it's got a lot of iron at the center of it.
link |
00:29:08.680
It's got a lot of electrons at the center of it.
link |
00:29:10.480
It's more oxidized on the outside,
link |
00:29:12.040
partly because of the sun and partly because the heat
link |
00:29:15.200
of volcanoes puts out oxidized gases.
link |
00:29:17.720
So the planet is a battery.
link |
00:29:19.640
It's a giant battery, and we have a flow of electrons
link |
00:29:23.400
going from inside to outside in these hydrothermal vents,
link |
00:29:26.200
and that's the same topology that a cell has.
link |
00:29:29.120
A cell is basically just a micro version of the planet,
link |
00:29:34.160
and there is a trajectory in all of that,
link |
00:29:37.000
and there's an inevitability that certain types
link |
00:29:39.360
of chemical reaction are going to be favored over others,
link |
00:29:42.360
and there's an inevitability in what happens in water,
link |
00:29:46.240
the chemistry that happens in water.
link |
00:29:47.880
Some will be immiscible with water and will form membranes
link |
00:29:51.840
and will form insoluble structures,
link |
00:29:53.320
and nobody really understands water very well,
link |
00:29:58.280
and it's another big question.
link |
00:30:00.680
For experiments on the origin of life, what do you put it in?
link |
00:30:04.440
What kind of structure do we want to induce in this water?
link |
00:30:07.200
Because the last thing it's likely to be
link |
00:30:08.840
is just kind of bulk water.
link |
00:30:11.640
How fundamental is water to life, would you say?
link |
00:30:14.240
I would say pretty fundamental.
link |
00:30:17.800
I wouldn't like to say it's impossible for life
link |
00:30:20.040
to start any other way, but water is everywhere.
link |
00:30:26.060
Water's extremely good at what it does,
link |
00:30:27.760
and carbon works in water especially well.
link |
00:30:31.160
So those things, and carbon is everywhere.
link |
00:30:33.240
So those things together make me think probabilistically,
link |
00:30:35.660
if we found a thousand life forms, 995 of them
link |
00:30:39.160
would be carbon based and living in water.
link |
00:30:41.920
Now the reverse question, if you found a puddle of water
link |
00:30:45.400
elsewhere and some carbon, no, just a puddle of water.
link |
00:30:50.200
Is a puddle of water a pretty damn good indication
link |
00:30:53.240
that life either exists here or has once existed here?
link |
00:31:00.960
No.
link |
00:31:02.340
So it doesn't work the other way.
link |
00:31:04.040
I think you need a living planet.
link |
00:31:07.580
You need a planet which is capable
link |
00:31:09.100
of turning over its surface.
link |
00:31:10.740
It needs to be a planet with water.
link |
00:31:12.860
It needs to be capable of bringing those electrons
link |
00:31:16.880
from inside to the outside.
link |
00:31:18.140
It needs to turn over its surface.
link |
00:31:19.660
It needs to make that water work and turn it into hydrogen.
link |
00:31:22.920
So I think you need a living planet.
link |
00:31:24.740
But once you've got the living planet,
link |
00:31:25.940
I think the rest of it is kind of thermodynamics all the way.
link |
00:31:29.420
So if you were to run Earth over a million times up
link |
00:31:34.500
to this point, maybe beyond, to the end,
link |
00:31:37.820
let's run it to the end, what is it?
link |
00:31:41.420
How much variety is there?
link |
00:31:42.980
You kind of spoke to this trajectory
link |
00:31:45.060
that the environment dictates chemically,
link |
00:31:49.900
I don't know in which other way, spiritually,
link |
00:31:53.560
I don't know, like dictates kind of the direction
link |
00:31:57.100
of this giant machine that seems chaotic,
link |
00:32:01.900
but it does seem to have order in the steps it's taking.
link |
00:32:06.180
How often will life, how often will bacteria emerge?
link |
00:32:11.420
How often will something like humans emerge?
link |
00:32:13.420
How much variety do you think there would be?
link |
00:32:15.320
I think at the level of bacteria, not much variety.
link |
00:32:19.400
I think we would get, that's how many times
link |
00:32:22.120
you say you want to run it, a million times.
link |
00:32:24.620
I would say at least a few hundred thousand will get bacteria again.
link |
00:32:28.020
Oh, wow, nice.
link |
00:32:29.460
Because I think there's some level of inevitability
link |
00:32:31.860
that a wet rocky planet will give rise
link |
00:32:33.980
through the same processes to something very close.
link |
00:32:38.260
I think this is not something I'd have thought
link |
00:32:40.460
a few years ago, but working with a PhD student
link |
00:32:43.380
of mine, Stuart Harrison, he's been thinking
link |
00:32:45.060
about the genetic code, and we've just been publishing
link |
00:32:47.580
on that, there are patterns that you can discern in the code,
link |
00:32:51.580
or he has discerned in the code,
link |
00:32:53.440
that if you think about them in terms of,
link |
00:32:56.100
we start with CO2 and hydrogen,
link |
00:32:57.780
and these are the first steps of biochemistry,
link |
00:32:59.780
you come up with a code which is very similar
link |
00:33:01.660
to the code that we see.
link |
00:33:03.660
So it wouldn't surprise me any longer
link |
00:33:05.580
if we found life on Mars and it had a genetic code
link |
00:33:07.800
that was not very different to the genetic code
link |
00:33:09.780
that we have here, without it just being transferred across.
link |
00:33:13.340
There's some inevitability about the whole
link |
00:33:16.180
of the beginnings of life, in my view.
link |
00:33:18.580
That's really promising, because if the basic chemistry
link |
00:33:21.540
is tightly linked to the genetic code,
link |
00:33:25.940
that means we can interact with other life
link |
00:33:29.540
if it exists out there.
link |
00:33:30.500
Well, that's potentially.
link |
00:33:32.140
That's really exciting, if that's the case.
link |
00:33:34.620
Okay, but then bacteria.
link |
00:33:36.060
We've got bacteria.
link |
00:33:37.800
Yeah.
link |
00:33:39.180
How easy is photosynthesis?
link |
00:33:42.920
Much harder, I would say.
link |
00:33:44.880
Let's actually go there.
link |
00:33:46.060
Let's go through the inventions.
link |
00:33:47.620
Yeah.
link |
00:33:49.160
What is photosynthesis?
link |
00:33:51.240
And why is it hard?
link |
00:33:52.420
Well, there are different forms.
link |
00:33:55.340
I mean, basically, you're taking hydrogen
link |
00:33:57.500
and you're sticking it onto CO2,
link |
00:33:59.000
and it's powered by the sun.
link |
00:34:00.340
Question is, where are you taking the hydrogen from?
link |
00:34:02.860
And in photosynthesis that we know in plants,
link |
00:34:05.340
it's coming from water.
link |
00:34:06.760
So you're using the power of the sun to split water,
link |
00:34:08.840
take out the hydrogen, stick it onto CO2,
link |
00:34:11.480
and the oxygen is a waste product,
link |
00:34:13.100
and you just throw it out, throw it away.
link |
00:34:15.660
So it's the single greatest planetary pollution event
link |
00:34:19.100
in the whole history of the Earth.
link |
00:34:21.340
The pollutant being oxygen.
link |
00:34:22.460
Yes, yeah.
link |
00:34:24.000
It also made possible animals.
link |
00:34:26.200
You can't have large, active animals
link |
00:34:28.460
without an oxygenated atmosphere,
link |
00:34:30.020
at least not in the sense that we know on Earth.
link |
00:34:33.700
So that's a really big invention
link |
00:34:35.540
in the history of Earth. Huge invention, yes.
link |
00:34:37.540
And it happened once.
link |
00:34:38.460
There's a few things that happen once on Earth,
link |
00:34:40.380
and you're always stuck with this problem.
link |
00:34:42.680
Once it happened, did it become so good so quickly
link |
00:34:44.780
that it precluded the same thing happening ever again?
link |
00:34:48.300
Or are there other reasons?
link |
00:34:49.500
And we really have to look at each one in turn
link |
00:34:51.220
and think, why did it only happen once?
link |
00:34:53.980
In this case, it's really difficult to split water.
link |
00:34:57.980
It requires a lot of power,
link |
00:34:59.140
and that power, you're effectively separating charge
link |
00:35:01.800
across a membrane, and the way in which you do it,
link |
00:35:04.040
if it doesn't all rush back
link |
00:35:05.340
and kind of cause an explosion right at the site,
link |
00:35:08.260
requires really careful wiring.
link |
00:35:10.700
And that wiring, it can't be easy to get it right
link |
00:35:14.740
because the plants that we see around us,
link |
00:35:18.700
they have chloroplasts.
link |
00:35:19.540
Those chloroplasts were cyanobacteria ones.
link |
00:35:21.340
Those cyanobacteria are the only group of bacteria
link |
00:35:23.620
that can do that type of photosynthesis.
link |
00:35:25.740
So there's plenty of opportunity.
link |
00:35:28.220
So not even many bacteria.
link |
00:35:29.520
So who invented photosynthesis?
link |
00:35:32.180
The cyanobacteria, or their ancestors.
link |
00:35:34.180
And there's not many?
link |
00:35:36.020
No other bacteria can do
link |
00:35:37.740
what's called oxygenic photosynthesis.
link |
00:35:39.740
Lots of other bacteria can split.
link |
00:35:42.100
I mean, you can take your hydrogen from somewhere else.
link |
00:35:44.080
You can take it from hydrogen sulfide
link |
00:35:45.500
bubbling out of a hydrothermal vent.
link |
00:35:47.220
Grab your two hydrogens.
link |
00:35:49.460
The sulfur is the waste now.
link |
00:35:52.100
You can do it from iron.
link |
00:35:53.300
You can take electrons.
link |
00:35:54.220
So the early oceans were probably full of iron.
link |
00:35:56.060
You can take an electron from ferrous iron,
link |
00:35:59.020
so iron two plus and make it iron three plus,
link |
00:36:01.620
which now precipitates as rust,
link |
00:36:03.960
and you take a proton from the acidic early ocean,
link |
00:36:07.620
stick it there.
link |
00:36:08.440
Now you've got a hydrogen atom.
link |
00:36:09.300
Stick it onto CO2.
link |
00:36:10.720
You've just done the trick.
link |
00:36:12.380
The trouble is you bury yourself in rusty iron.
link |
00:36:16.460
And with sulfur, you can bury yourself in sulfur.
link |
00:36:18.540
One of the reasons oxygenic photosynthesis
link |
00:36:20.700
is so much better is that the waste product is oxygen,
link |
00:36:23.340
which just bubbles away.
link |
00:36:26.420
That seems like extremely unlikely,
link |
00:36:29.220
and it's extremely essential
link |
00:36:30.740
for the evolution of complex organisms
link |
00:36:33.720
because of all the oxygen.
link |
00:36:36.120
Yeah, and that didn't accumulate quickly either.
link |
00:36:39.420
So it's converting, what is it?
link |
00:36:42.060
It's converting energy from the sun
link |
00:36:44.820
and the resource of water
link |
00:36:46.960
into the resource needed for animals.
link |
00:36:50.820
Both resources needed for animals.
link |
00:36:52.400
We need to eat, and we need to burn the food,
link |
00:36:54.540
and we're eating plants,
link |
00:36:57.780
which are getting their energy from the sun,
link |
00:36:59.300
and we're burning it with their waste product,
link |
00:37:01.260
which is the oxygen.
link |
00:37:02.540
So there's a lot of kind of circularity in that,
link |
00:37:04.620
but without an oxygenated planet,
link |
00:37:07.880
you couldn't really have predation.
link |
00:37:12.560
You can have animals,
link |
00:37:14.980
but you can't really have animals
link |
00:37:16.240
that go around and eat each other.
link |
00:37:17.440
You can't have ecosystems as we know them.
link |
00:37:19.900
Well, let's actually step back.
link |
00:37:21.120
What about eukaryotic versus prokaryotic cells, prokaryotes?
link |
00:37:25.620
What are each of those,
link |
00:37:28.420
and how big of an invention is that?
link |
00:37:31.060
I personally think that's the single biggest invention
link |
00:37:33.380
in the whole history of life.
link |
00:37:34.820
Exciting.
link |
00:37:35.900
So what are they?
link |
00:37:36.900
Can you explain?
link |
00:37:37.740
Yeah, so I mentioned bacteria and archaea.
link |
00:37:40.780
These are both prokaryotes.
link |
00:37:43.020
They're basically small cells that don't have a nucleus.
link |
00:37:45.740
If you look at them under a microscope,
link |
00:37:47.060
you don't see much going on.
link |
00:37:48.140
If you look at them under a super resolution microscope,
link |
00:37:50.640
then they're fantastically complex.
link |
00:37:53.220
In terms of their molecular machinery, they're amazing.
link |
00:37:55.460
In terms of their morphological appearance
link |
00:37:58.360
under a microscope, they're really small and really simple.
link |
00:38:03.060
The earliest life that we can physically see
link |
00:38:04.900
on the planet are stromatolites,
link |
00:38:06.380
which are made by things like cyanobacteria,
link |
00:38:08.500
and they're large superstructures.
link |
00:38:11.020
Effectively, biofilms plated on top of each other,
link |
00:38:14.420
and you end up with quite large structures
link |
00:38:17.360
that you can see in the fossil record.
link |
00:38:19.780
But they never came up with animals.
link |
00:38:23.100
They never came up with plants.
link |
00:38:24.320
They came up with multicellular things,
link |
00:38:26.660
filamentous cyanobacteria, for example.
link |
00:38:28.620
They're just long strings of cells.
link |
00:38:31.420
But the origin of the eukaryotic cell
link |
00:38:34.500
seems to have been what's called an endosymbiosis,
link |
00:38:37.300
so one cell gets inside another cell.
link |
00:38:39.620
And I think that that's transformed
link |
00:38:42.160
the energetic possibilities of life.
link |
00:38:43.780
So what we end up with is a kind of supercharged cell,
link |
00:38:48.160
which can have a much larger nucleus
link |
00:38:50.460
with many more genes, all supported.
link |
00:38:54.180
If you think about it, you could think about it
link |
00:38:55.780
as multi bacterial power without the overhead.
link |
00:38:58.340
So you've got a cell and it's got bacteria living in it,
link |
00:39:00.860
and those bacteria are providing it
link |
00:39:02.260
with the energy currency it needs.
link |
00:39:04.700
But each bacterium has a genome of its own,
link |
00:39:07.060
which costs a fair amount of energy to express,
link |
00:39:10.340
to kind of turn over and convert into proteins and so on.
link |
00:39:15.060
What the mitochondria did,
link |
00:39:16.780
which are these power packs in our own cells,
link |
00:39:20.500
they were bacteria once,
link |
00:39:22.340
and they threw away virtually all their genes.
link |
00:39:24.100
They've only got a few left.
link |
00:39:25.660
So mitochondria is, like you said,
link |
00:39:27.720
is the bacteria that got inside a cell
link |
00:39:30.120
and then throw away all this stuff it doesn't need to,
link |
00:39:32.300
survive inside the cell, and then kept what?
link |
00:39:35.260
So what we end up with,
link |
00:39:36.340
so it kept always a handful of genes.
link |
00:39:38.820
In our own case, 37 genes.
link |
00:39:41.580
But there's a few protists, which are single celled things
link |
00:39:44.620
that have got as many as 70 or 80 genes.
link |
00:39:47.220
So it's not always the same, but it's always a small number.
link |
00:39:51.220
And you can think of it as a paired down power pack
link |
00:39:54.180
where the control unit has really been,
link |
00:39:56.020
has been kind of paired down to almost nothing.
link |
00:39:58.800
So you're putting out the same power,
link |
00:40:00.860
but the investment in the overheads is really paired down.
link |
00:40:04.380
That means that you can support
link |
00:40:05.740
a much larger nuclear genome.
link |
00:40:08.420
So we've gone up in the number of genes,
link |
00:40:10.540
but also the amount of power you have
link |
00:40:12.220
to convert those genes into proteins.
link |
00:40:14.940
We've gone up about fourfold in the number of genes,
link |
00:40:17.100
but in terms of the size of genomes
link |
00:40:19.260
and your ability to make the building blocks,
link |
00:40:21.840
make the proteins, we've gone up 100,000 fold or more.
link |
00:40:25.100
So it's huge step change in the possibilities of evolution.
link |
00:40:29.540
And it's interesting then that the only two occasions
link |
00:40:33.980
that complex life has arisen on Earth,
link |
00:40:35.900
plants and animals,
link |
00:40:38.060
fungi you could say are complex as well,
link |
00:40:40.140
but they don't form such complex morphology
link |
00:40:42.820
as plants and animals.
link |
00:40:44.540
Start with a single cell.
link |
00:40:45.660
They start with an oocyte and a sperm
link |
00:40:48.380
fused together to make a zygote.
link |
00:40:50.420
So we start development with a single cell
link |
00:40:52.300
and all the cells in the organism have identical DNA.
link |
00:40:56.460
And you switch off in the brain,
link |
00:40:58.340
you switch off these genes and you switch on those genes
link |
00:41:00.540
and liver, you switch off those
link |
00:41:01.700
and you switch on a different set.
link |
00:41:04.060
And the standard evolutionary explanation for that
link |
00:41:06.120
is that you're restricting conflict.
link |
00:41:08.580
You don't have a load of genetically different cells
link |
00:41:10.980
that are all fighting each other.
link |
00:41:13.340
And so it works.
link |
00:41:14.700
The trouble with bacteria, they form these biofilms
link |
00:41:17.180
and they're all genetically different.
link |
00:41:18.520
And effectively they're incapable
link |
00:41:21.020
of that level of cooperation.
link |
00:41:23.300
They would get in a fight.
link |
00:41:26.380
Okay, so why is this such a difficult invention
link |
00:41:31.180
of getting this bacteria inside
link |
00:41:33.380
and becoming an engine which the mitochondria is?
link |
00:41:37.300
Why do you assign it such great importance?
link |
00:41:40.420
Is it great importance in terms of the difficulty
link |
00:41:42.180
of how it was to achieve or great importance
link |
00:41:44.300
in terms of the impact it had on life?
link |
00:41:46.900
Both.
link |
00:41:48.380
It had a huge impact on life
link |
00:41:49.780
because if that had not happened,
link |
00:41:52.500
you can be certain that life on earth
link |
00:41:54.940
would be bacterial only.
link |
00:41:56.500
And that took a really long time too.
link |
00:41:58.180
It took 2 billion years.
link |
00:41:59.940
And it hasn't happened since to the best of our knowledge.
link |
00:42:02.740
So it looks as if it's genuinely difficult.
link |
00:42:05.100
And if you think about it then
link |
00:42:06.200
from just an informational perspective,
link |
00:42:08.500
you think bacteria have got,
link |
00:42:12.380
they structure their information differently.
link |
00:42:15.260
So a bacterial cell has a small genome,
link |
00:42:17.540
you might have 4,000 genes in it,
link |
00:42:19.060
but a single E. coli cell has access
link |
00:42:21.100
to about 30,000 genes potentially.
link |
00:42:24.060
It's got a kind of metagenome
link |
00:42:26.020
where other E. coli out there
link |
00:42:27.860
have got different gene sets
link |
00:42:29.060
and they can switch them around between themselves.
link |
00:42:31.820
And so you can generate a huge amount of variation
link |
00:42:34.580
and they've got more,
link |
00:42:36.220
an E. coli metagenome is larger than the human genome.
link |
00:42:40.620
We own 20,000 genes or something.
link |
00:42:43.220
So, and they've had 4 billion years of evolution
link |
00:42:46.900
to work out what can I do
link |
00:42:48.540
and what can't I do with this metagenome?
link |
00:42:51.540
And the answer is you're stuck, you're still bacteria.
link |
00:42:54.300
So they have explored genetic sequence space
link |
00:42:58.940
far more thoroughly than eukaryotes ever did
link |
00:43:01.260
because they've had twice as long at least
link |
00:43:03.060
and they've got much larger populations
link |
00:43:05.940
and they never got around this problem.
link |
00:43:08.420
So why can't they?
link |
00:43:09.340
It seems as if you can't solve it with information alone.
link |
00:43:12.420
So what's the problem?
link |
00:43:14.860
The problem is structure.
link |
00:43:16.400
If the very first cells needed an electrical charge
link |
00:43:21.020
on their membrane to grow and in bacteria,
link |
00:43:23.820
it's the outer membrane that surrounds the cell
link |
00:43:26.220
which is electrically charged.
link |
00:43:28.220
You try and scale that up
link |
00:43:29.740
and you've got a fundamental design problem,
link |
00:43:31.940
you've got an engineering problem.
link |
00:43:33.680
And there are examples of it
link |
00:43:35.260
and what we see in all these cases
link |
00:43:37.080
is what's known as extreme polyploidy,
link |
00:43:38.780
which is to say they have tens of thousands of copies
link |
00:43:41.020
of their complete genome,
link |
00:43:42.740
which is energetically hugely expensive
link |
00:43:45.520
and you end up with a large bacteria
link |
00:43:49.020
with no further development.
link |
00:43:52.340
What you need is to incorporate
link |
00:43:55.020
these electrically charged power pack units inside
link |
00:43:58.500
with their control units intact
link |
00:44:01.380
and for them not to conflict so much with the host cell
link |
00:44:03.980
that it all goes wrong.
link |
00:44:05.900
Perhaps it goes wrong more often than not.
link |
00:44:07.860
And then you change the topology of the cell.
link |
00:44:10.940
Now you don't necessarily have any more DNA
link |
00:44:14.220
than a giant bacterium with extreme polyploidy,
link |
00:44:16.740
but what you've got is an asymmetry.
link |
00:44:19.340
You now have a giant nuclear genome
link |
00:44:21.940
which surrounded by lots of subsidiary energetic genomes
link |
00:44:25.640
that do all the, they're the control units
link |
00:44:27.920
that are doing all the control of energy generation.
link |
00:44:32.340
Could this have been done gradually
link |
00:44:33.980
or does it have to be done,
link |
00:44:35.900
the power pack has to be all intact
link |
00:44:38.180
and ready to go and working?
link |
00:44:40.180
I mean, it's a kind of step change
link |
00:44:41.860
in the possibilities of evolution,
link |
00:44:43.420
but it doesn't happen overnight.
link |
00:44:44.540
It's gonna still require multiple, multiple generations.
link |
00:44:47.700
So it could take millions of years.
link |
00:44:50.900
It could take shorter times.
link |
00:44:52.220
There's another thing I would like to put the number of steps
link |
00:44:54.100
and try and work out what's required at each step.
link |
00:44:56.180
And we are trying to do that with sex for example.
link |
00:44:58.500
You can't have a very large genome
link |
00:45:00.820
unless you have sex at that point.
link |
00:45:02.220
So what are the changes to go
link |
00:45:03.340
from bacterial recombination to eukaryotic recombination?
link |
00:45:07.860
What do you need to do?
link |
00:45:09.540
Why do we go from passing around bits of DNA
link |
00:45:12.340
as if it's loose change to fusing cells together,
link |
00:45:15.340
lining up the chromosomes,
link |
00:45:16.580
recombining across the chromosomes,
link |
00:45:18.620
and then going through two rounds of cell division
link |
00:45:20.820
to produce your gametes?
link |
00:45:22.340
All eukaryotes do it that way.
link |
00:45:24.440
So again, why switch?
link |
00:45:27.420
What are the drivers here?
link |
00:45:28.780
So there's a lot of time, there's a lot of evolution,
link |
00:45:31.420
but as soon as you've got cells living inside another cell,
link |
00:45:34.100
what you've got is a new design.
link |
00:45:36.340
You've got new potential that you didn't have before.
link |
00:45:39.100
So the cell living inside another cell, that design
link |
00:45:44.220
allows for better storage of information,
link |
00:45:48.700
better use of energy, more delegation,
link |
00:45:52.780
like a hierarchical control of the whole thing.
link |
00:45:55.420
And then somehow that leads to ability
link |
00:45:58.340
to have multi cell organisms.
link |
00:46:00.180
I'm not sure that you have hierarchical control necessarily,
link |
00:46:03.300
but you've got a system where you can have
link |
00:46:06.460
a much larger information storage depot in the nucleus.
link |
00:46:09.940
You can have a much larger genome.
link |
00:46:11.700
And that allows multicellularity, yes,
link |
00:46:13.620
because it allows you, it's a funny thing,
link |
00:46:18.500
to have an animal where I have 70% of my genes
link |
00:46:24.140
switched on in my brain,
link |
00:46:25.260
and a different 50% switched on in my liver or something,
link |
00:46:28.500
you've got to have all those genes in the egg cell
link |
00:46:30.860
at the very beginning,
link |
00:46:31.780
and you've got to have a program of development
link |
00:46:35.500
which says, okay, you guys switch off those genes
link |
00:46:37.900
and switch on those genes, and you guys, you do that.
link |
00:46:40.300
But all the genes are there at the beginning.
link |
00:46:42.180
That means you've got to have a lot of genes in one cell
link |
00:46:44.100
and you've got to be able to maintain them.
link |
00:46:45.620
And the problem with bacteria is they don't get close
link |
00:46:47.660
to having enough genes in one cell.
link |
00:46:49.900
So if you were to try and make a multicellular organism
link |
00:46:52.760
from bacteria, you'd bring different types
link |
00:46:54.500
of bacteria together and hope they'll cooperate.
link |
00:46:56.540
And the reality is they don't.
link |
00:46:57.940
That's really, really tough to do.
link |
00:46:59.540
Yeah.
link |
00:47:00.380
We know they don't because it doesn't exist.
link |
00:47:02.700
We have the data as far as we know.
link |
00:47:04.580
I'm sure there's a few special ones
link |
00:47:06.420
and they dead off quickly.
link |
00:47:08.180
I'd love to know some of the most fun things
link |
00:47:09.980
bacteria have done since.
link |
00:47:12.660
Oh, there's a few.
link |
00:47:13.500
I mean, they can do some pretty funky things.
link |
00:47:15.460
And this is broad brushstroke that I'm talking about.
link |
00:47:18.260
Yes.
link |
00:47:19.200
Generally speaking.
link |
00:47:21.060
So how was, so another fun invention.
link |
00:47:25.060
Us humans seem to utilize it well,
link |
00:47:27.820
but you say it's also very important early on is sex.
link |
00:47:31.540
So what is sex?
link |
00:47:34.540
Just asking for a friend.
link |
00:47:36.380
And when was it invented and how hard was it to invent,
link |
00:47:39.300
just as you were saying, and why was it invented?
link |
00:47:42.340
Why, how hard was it and when?
link |
00:47:45.660
I have a PhD student who's been working on this
link |
00:47:47.980
and we've just published a couple of papers on sex.
link |
00:47:49.980
Yes, yes, yes.
link |
00:47:50.900
What do you publish?
link |
00:47:51.740
Does biology, is it biology, genetics, journals?
link |
00:47:55.540
This is actually PNAS,
link |
00:47:57.220
which is Proceedings of the National Academy.
link |
00:48:00.180
Broad, big, big picture stuff.
link |
00:48:02.420
Everyone's interested in sex.
link |
00:48:03.500
Yeah.
link |
00:48:04.340
And the job of a biologist is to make sex dull.
link |
00:48:07.940
Yes, yeah, that's a beautiful way to put it.
link |
00:48:10.700
Okay, so when was it invented?
link |
00:48:13.220
It was invented with eukaryotes about two billion years ago.
link |
00:48:16.940
All eukaryotes share the same basic mechanism
link |
00:48:20.900
that you produce gametes, the gametes fuse together.
link |
00:48:23.420
So a gamete is the egg cell and the sperm.
link |
00:48:26.300
They're not necessarily even different in size or shape.
link |
00:48:29.580
So the simplest eukaryotes produce
link |
00:48:31.860
what are called motile gametes.
link |
00:48:32.980
They're all like sperm and they all swim around.
link |
00:48:34.900
They find each other, they fuse together.
link |
00:48:36.420
They don't have kind of much going on there beyond that.
link |
00:48:39.940
And then these are haploid,
link |
00:48:43.180
which is to say we all have two copies of our genome
link |
00:48:46.100
and the gametes have only a single copy of the genome.
link |
00:48:49.220
So when they fuse together, you now become diploid again,
link |
00:48:51.980
which is to say you now have two copies of your genome.
link |
00:48:55.100
And what you do is you line them all up
link |
00:48:57.820
and then you double everything.
link |
00:49:01.620
So now we have four copies of the complete genome.
link |
00:49:03.900
And then we crisscross between all of these things.
link |
00:49:05.980
So we take a bit from here and stick it on there
link |
00:49:07.660
and a bit from here and we stick it on here.
link |
00:49:09.620
That's recombination.
link |
00:49:11.740
And then we go through two rounds of cell division.
link |
00:49:14.820
So we divide in half.
link |
00:49:15.900
So now the two daughter cells have two copies
link |
00:49:18.020
and we divide in half again.
link |
00:49:19.460
Now we have some gametes,
link |
00:49:21.220
each of which has got a single copy of the genome.
link |
00:49:24.460
And that's the basic ground plan
link |
00:49:26.660
for what's called meiosis and Syngami.
link |
00:49:29.780
That's basically sex.
link |
00:49:31.340
And it happens at the level of single celled organisms.
link |
00:49:33.900
And it happens pretty much the same way in plants
link |
00:49:35.780
and pretty much the same way in animals and so on.
link |
00:49:38.140
And it's not found in any bacteria.
link |
00:49:40.220
They switch things around using the same machinery
link |
00:49:43.100
and they take up a bit of DNA from the environment.
link |
00:49:44.900
They take out this bit and stick in that bit
link |
00:49:46.620
and it's the same molecular machinery they're using to do it.
link |
00:49:50.020
So what about the kind of, you said, find each other,
link |
00:49:52.660
this kind of imperative, find each other.
link |
00:49:56.020
What is that?
link |
00:49:57.300
Like, is that?
link |
00:49:58.260
Well, you've got a few cells together.
link |
00:50:00.660
So the bottom line on all of this is bacteria.
link |
00:50:04.420
I mean, it's kind of simple when you've figured it out
link |
00:50:07.820
and figuring it out, this is not me,
link |
00:50:09.300
this is my PhD student, Marco Colnaghi.
link |
00:50:13.020
And in effect, if you're doing lateral,
link |
00:50:16.420
you're a Nicoli cell, you've got 4,000 genes.
link |
00:50:19.740
You wanna scale up to a eukaryotic size.
link |
00:50:22.900
I wanna have 20,000 genes.
link |
00:50:25.380
And I need to maintain my genome
link |
00:50:27.740
so it doesn't get shot to pieces by mutations.
link |
00:50:30.460
And I'm gonna do it by lateral gene transfer.
link |
00:50:32.700
So I know I've got a mutation in a gene.
link |
00:50:35.420
I don't know which gene it is because I'm not sentient,
link |
00:50:38.820
but I know I can't grow.
link |
00:50:40.220
I know all my regulation systems are saying,
link |
00:50:42.460
something wrong here, something wrong, pick up some DNA,
link |
00:50:44.980
pick up a bit of DNA from the environment.
link |
00:50:47.700
If you've got a small genome,
link |
00:50:49.060
the chances of you picking up the right bit of DNA
link |
00:50:50.980
from the environment is much higher
link |
00:50:52.340
than if you've got a genome of 20,000 genes.
link |
00:50:54.780
To do that, you've effectively got to be picking up DNA
link |
00:50:58.060
all the time, all day long and nothing else.
link |
00:51:00.500
And you're still gonna get the wrong DNA.
link |
00:51:02.220
You've got to pick up large chunks.
link |
00:51:03.720
And in the end, you've got to align them.
link |
00:51:05.100
You're forced into sex, to coin a phrase.
link |
00:51:10.220
So you're...
link |
00:51:11.060
You're forced.
link |
00:51:12.540
So there is a kind of incentive.
link |
00:51:18.660
If you wanna have a large genome,
link |
00:51:20.100
you've got to prevent it mutating to nothing.
link |
00:51:22.620
That will happen with bacteria.
link |
00:51:23.940
This is another reason why bacteria
link |
00:51:25.640
can't have a large genome.
link |
00:51:26.940
But as soon as you give them the power pack,
link |
00:51:28.660
as soon as you give eukaryotic cells the power pack
link |
00:51:30.340
that allows them to increase the size of their genome,
link |
00:51:33.020
then you face the pressure
link |
00:51:34.380
that you've got to maintain its quality.
link |
00:51:36.300
You've got to stop it just mutating away.
link |
00:51:38.340
What about sexual selection?
link |
00:51:39.820
So the finding, like, I don't like this one.
link |
00:51:44.740
I don't like this one.
link |
00:51:45.740
This one seems all right.
link |
00:51:47.220
Like, what's the...
link |
00:51:49.820
Is it...
link |
00:51:50.660
At which point does it become less random?
link |
00:51:52.740
It's hard to know.
link |
00:51:54.140
Because eukaryotes just kind of float around.
link |
00:51:56.020
Just kind of have...
link |
00:51:57.020
Yeah, I mean, is there sexual selection
link |
00:51:59.060
in single celled eukaryotes?
link |
00:52:00.300
There probably is.
link |
00:52:01.120
It's just that I don't know very much about it.
link |
00:52:02.940
By the time we get onto...
link |
00:52:03.780
You don't hang out with the eukaryotes.
link |
00:52:05.700
Well, I do all the time, but...
link |
00:52:07.380
But you can't communicate with them yet.
link |
00:52:09.020
Yeah, a peacock or something.
link |
00:52:10.980
Yes.
link |
00:52:12.780
The kind of standard answer,
link |
00:52:14.180
this is not quite what I work on,
link |
00:52:15.520
but the standard answer is that it's female mate choice.
link |
00:52:19.780
She is looking for good genes.
link |
00:52:22.980
And if you can have a tail that's like this
link |
00:52:25.660
and still survive, still be alive,
link |
00:52:28.100
not actually have been taken down by the nearest predator,
link |
00:52:30.420
then you must've got pretty good genes
link |
00:52:31.780
because despite this handicap, you're able to survive.
link |
00:52:36.460
So those are like human interpretable things,
link |
00:52:38.340
like with a peacock.
link |
00:52:39.220
But I wonder, I'm sure echoes of the same thing
link |
00:52:43.020
are there with more primitive organisms.
link |
00:52:46.540
Basically your PR, like how you advertise yourself
link |
00:52:51.220
that you're worthy of.
link |
00:52:54.020
Absolutely.
link |
00:52:54.860
So one big advertisement is the fact
link |
00:52:56.460
that you survived it all.
link |
00:52:58.420
Let me give you one beautiful example of an algal bloom.
link |
00:53:03.020
And this can be a sign of bacteria.
link |
00:53:05.540
It's gonna be in bacteria.
link |
00:53:07.100
So if suddenly you pump nitrate or phosphate
link |
00:53:10.780
or something into the ocean and everything goes green,
link |
00:53:13.340
you end up with all this algae growing there.
link |
00:53:18.180
A viral infection or something like that
link |
00:53:20.860
can kill the entire bloom overnight.
link |
00:53:23.380
And it's not that the virus takes out everything overnight.
link |
00:53:26.860
It's that most of the cells in that bloom kill themselves
link |
00:53:29.700
before the virus can get onto them.
link |
00:53:31.900
And it's through a form of cell death
link |
00:53:33.740
called programmed cell death.
link |
00:53:35.020
And we do the same things.
link |
00:53:36.580
It's how we have the gaps between our fingers and so on.
link |
00:53:39.980
It's how we craft synapses in the brain.
link |
00:53:43.060
It's fundamental again to multicellular life.
link |
00:53:47.420
They have the same machinery in these algal blooms.
link |
00:53:51.220
How do they know who dies?
link |
00:53:52.900
The answer is they will often put out a toxin.
link |
00:53:56.740
And that toxin is kind of a challenge to you.
link |
00:54:00.300
Either you can cope with the toxin or you can't.
link |
00:54:03.420
If you can cope with it, you form a spore
link |
00:54:06.460
and you will go on to become the next generation.
link |
00:54:09.100
You're forming kind of a resistance spore.
link |
00:54:11.940
You sink down a little bit, you get out of the way,
link |
00:54:14.180
you're out of the, you can't be attacked by a virus
link |
00:54:17.540
if you're a spore or it's not so easily.
link |
00:54:19.660
Whereas if you can't deal with that toxin,
link |
00:54:21.900
you pull the plug and you trigger your death apparatus
link |
00:54:25.700
and you kill yourself.
link |
00:54:27.100
Oh, so it's truly life and death selection.
link |
00:54:29.140
Yeah, so it's really, it's a challenge.
link |
00:54:31.620
And this is a bit like sexual selection.
link |
00:54:33.620
It's not so, they're all pretty much genetically identical,
link |
00:54:36.940
but they've had different life histories.
link |
00:54:39.020
So have you had a tough day?
link |
00:54:41.420
Did you happen to get infected by this virus?
link |
00:54:44.460
Or did you run out of iron?
link |
00:54:45.540
Or did you get a bit too much sun?
link |
00:54:47.460
Whatever it may be, if this extra stress of the toxin
link |
00:54:51.180
just pushes you over the edge,
link |
00:54:52.820
then you have this binary choice.
link |
00:54:53.980
Either you're the next generation
link |
00:54:55.180
or you kill yourself now using this same machinery.
link |
00:54:57.920
It's also actually exactly the way I approach dating,
link |
00:55:00.660
but that's probably why I'm single.
link |
00:55:03.220
Okay, what about if we can step back, DNA?
link |
00:55:07.360
Just mechanism of storing information.
link |
00:55:10.460
RNA, DNA, how big of an invention was that?
link |
00:55:13.460
That seems to be, that seems to be fundamental
link |
00:55:16.180
to like something deep within what life is,
link |
00:55:22.540
is the ability, as you said,
link |
00:55:24.060
to kind of store and propagate information.
link |
00:55:28.000
But then you also kind of infer that
link |
00:55:29.900
with your and your students work,
link |
00:55:31.600
that there's a deep connection between the chemistry
link |
00:55:35.140
and the ability to have this kind of genetic information.
link |
00:55:39.060
So how big of an invention is it
link |
00:55:41.140
to have a nice representation,
link |
00:55:43.740
nice hard drive for info to pass on?
link |
00:55:46.300
Huge, I suspect.
link |
00:55:47.940
I mean, but when I was talking about the code,
link |
00:55:50.580
you see the code in RNA as well.
link |
00:55:52.600
And RNA almost certainly came first.
link |
00:55:56.100
And there's been an idea going back decades
link |
00:55:58.580
called the RNA world,
link |
00:55:59.740
because RNA in theory can copy itself
link |
00:56:03.060
and can catalyze reactions.
link |
00:56:04.900
So it kind of cuts out this chicken and egg loop.
link |
00:56:07.860
So DNA as possible is not that special.
link |
00:56:09.900
So RNA, RNA is the thing that does the work really.
link |
00:56:13.560
And the code lies in RNA.
link |
00:56:15.340
The code lies in the interactions
link |
00:56:16.900
between RNA and amino acids.
link |
00:56:18.340
And it still is there today in the ribosome, for example,
link |
00:56:21.700
which is just kind of a giant ribozyme,
link |
00:56:23.820
which is to say it's an enzyme that's made of RNA.
link |
00:56:28.200
So getting to RNA, I suspect is probably not that hard,
link |
00:56:34.180
but getting from RNA, how do you,
link |
00:56:37.180
you know, there's multiple different types of RNA now.
link |
00:56:39.860
How do you distinguish?
link |
00:56:42.380
This is something we're actively thinking about.
link |
00:56:43.860
How do you distinguish between,
link |
00:56:45.580
you know, a random population of RNA?
link |
00:56:47.220
Some of them go on to become messenger RNA.
link |
00:56:50.300
This is the transcript of the code
link |
00:56:52.540
of the gene that you want to make.
link |
00:56:54.240
Some of them become transfer RNA,
link |
00:56:56.860
which is kind of the unit that holds the amino acid
link |
00:56:59.900
that's going to be polymerized.
link |
00:57:01.720
Some of them become ribosomal RNA,
link |
00:57:04.300
which is the machine which is joining them all up together.
link |
00:57:07.540
How do they discriminate themselves?
link |
00:57:10.140
And, you know, is some kind of phase transition
link |
00:57:12.340
going on there?
link |
00:57:13.180
I don't know.
link |
00:57:14.220
It's a difficult question.
link |
00:57:16.060
And we're now in the region of biology
link |
00:57:18.300
where information is coming in.
link |
00:57:19.700
But the thing about RNA is very, very good at what it does.
link |
00:57:22.940
But the largest genome supported by RNA
link |
00:57:25.620
are RNA viruses like HIV, for example.
link |
00:57:28.880
They're pretty small.
link |
00:57:29.880
And so there's a limit to how complex life could be
link |
00:57:34.660
unless you come up with DNA,
link |
00:57:36.380
which chemically is a really small change.
link |
00:57:39.220
But how easy it is to make that change,
link |
00:57:41.780
I don't really know.
link |
00:57:42.620
As soon as you've got DNA,
link |
00:57:43.980
then you've got an amazingly stable molecule
link |
00:57:46.660
for information storage.
link |
00:57:48.440
And you can do absolutely anything.
link |
00:57:50.580
But how likely that transition from RNA to DNA was,
link |
00:57:53.260
I don't know either.
link |
00:57:54.460
How much possibility is there for variety
link |
00:57:56.920
in ways to store information?
link |
00:58:00.440
Because it seems to be very,
link |
00:58:01.480
there's specific characteristics
link |
00:58:03.040
about the programming language of DNA.
link |
00:58:06.600
Yeah, there's a lot of work going on
link |
00:58:08.320
on what's called the xenodNA or RNA.
link |
00:58:11.880
Can we replace the bases themselves,
link |
00:58:15.440
the letters, if you like, in RNA or DNA?
link |
00:58:18.320
Can we replace the backbone?
link |
00:58:19.880
Can we replace, for example, phosphate with arsenate?
link |
00:58:23.240
Can we replace the sugar ribose or deoxyribose
link |
00:58:25.940
with a different sugar?
link |
00:58:26.780
And the answer is yes, you can.
link |
00:58:29.880
Within limits, there's not an infinite space there.
link |
00:58:34.240
Arsenate doesn't really work
link |
00:58:36.080
if the bonds are not as strong as phosphate.
link |
00:58:38.000
It's probably quite hard to replace phosphate.
link |
00:58:42.360
It's possible to do it.
link |
00:58:43.520
The question to me is why is it this way?
link |
00:58:47.560
Is it because there was some form of selection
link |
00:58:50.300
that this is better than the other forms
link |
00:58:52.160
and there were lots of competing forms
link |
00:58:53.720
of information storage early on
link |
00:58:55.160
and this one was the one that worked out?
link |
00:58:56.840
Or was it kind of channeled that way,
link |
00:58:58.520
that these are the molecules that you're dealing with
link |
00:59:01.960
and they work?
link |
00:59:03.960
And I'm increasingly thinking it's that way,
link |
00:59:05.840
that we're channeled towards ribose, phosphate,
link |
00:59:08.880
and the bases that are used.
link |
00:59:11.960
But there are 200 different letters
link |
00:59:14.560
kicking around out there that could have been used.
link |
00:59:17.160
It's such an interesting question.
link |
00:59:18.280
If you look in the programming world in computer science,
link |
00:59:21.840
there's a programming language called JavaScript,
link |
00:59:24.200
which was written super quickly.
link |
00:59:26.360
It's a giant mess, but it took over the world.
link |
00:59:29.440
And it was kind of a...
link |
00:59:30.280
Sounds very biological.
link |
00:59:31.320
It was kind of a running joke that like,
link |
00:59:35.080
like surely this can't be,
link |
00:59:37.800
this is a terrible programming language.
link |
00:59:39.560
It's a giant mess.
link |
00:59:40.400
It's full of bugs.
link |
00:59:41.760
It's so easy to write really crappy code,
link |
00:59:44.080
but it took over all a front end development
link |
00:59:48.040
in the web browser.
link |
00:59:49.340
If you have any kind of dynamic interactive website,
link |
00:59:52.280
it's usually running JavaScript.
link |
00:59:54.940
And it's now taking over much of the backend,
link |
00:59:57.840
which is like the serious heavy duty computational stuff.
link |
01:00:00.920
And it's become super fast
link |
01:00:02.700
with the different compilation engines that are running it.
link |
01:00:06.560
So it's like, it really took over the world.
link |
01:00:08.120
It's very possible that this initially crappy derided language
link |
01:00:13.760
actually takes everything over.
link |
01:00:14.880
And then the question is,
link |
01:00:17.280
did human civilization always strive towards JavaScript?
link |
01:00:21.800
Or was JavaScript just the first programming language
link |
01:00:25.160
that ran on the browser and still sticky?
link |
01:00:27.200
The first is the sticky one.
link |
01:00:29.880
And so it wins over anything else because it was first.
link |
01:00:32.680
And I don't think that's answerable, right?
link |
01:00:34.640
But it's good to ask that.
link |
01:00:37.160
I suppose in the lab,
link |
01:00:38.920
you can't run it with programming languages,
link |
01:00:43.400
but in biology you can probably do some kind of
link |
01:00:47.440
small scale evolutionary test to try to infer,
link |
01:00:53.520
which is which.
link |
01:00:54.760
Yeah.
link |
01:00:55.600
I mean, in a way we've got the hardware
link |
01:00:57.040
and the software here.
link |
01:00:58.640
And the hardware is maybe the DNA and the RNA itself.
link |
01:01:02.880
And then the software perhaps is more about the code.
link |
01:01:06.200
Did the code have to be this way?
link |
01:01:07.440
Could it have been a different way?
link |
01:01:09.360
People talk about the optimization of the code
link |
01:01:11.440
and there's some suggestion for that.
link |
01:01:14.040
I think it's weak actually.
link |
01:01:16.080
But you could imagine you could come out
link |
01:01:17.560
with a million different codes
link |
01:01:18.840
and this would be one of the best ones.
link |
01:01:22.520
Well, we don't know this.
link |
01:01:24.320
Well, I mean, people have tried to model it
link |
01:01:27.400
based on the effect that mutations would have.
link |
01:01:31.160
So no, you're right.
link |
01:01:32.040
We don't know because that's a single assumption
link |
01:01:34.120
that a mutation is what's being selected on there.
link |
01:01:37.760
And there's other possibilities too.
link |
01:01:39.320
I mean, there does seem to be a resilience
link |
01:01:41.160
and a redundancy to the whole thing.
link |
01:01:43.200
It's hard to mess up and the way you mess it up
link |
01:01:47.640
often is likely to produce interesting results.
link |
01:01:51.600
So it's...
link |
01:01:52.760
Are you talking about JavaScript or the genetic code now?
link |
01:01:55.480
Yeah, well, I mean, it's almost,
link |
01:01:57.840
biology is underpinned by this kind of mess as well.
link |
01:02:00.640
And you look at the human genome and it's full of stuff
link |
01:02:03.400
that is really either broken or dysfunctional
link |
01:02:06.160
or was a virus once, whatever it may be.
link |
01:02:08.080
And somehow it works.
link |
01:02:09.280
And maybe we need a lot of this mess.
link |
01:02:11.640
We know that some functional genes are taken from this mess.
link |
01:02:15.400
So what about, you mentioned the predatory behavior.
link |
01:02:19.560
Yeah.
link |
01:02:20.400
We talked about sex.
link |
01:02:21.440
What about violence, predator and prey dynamics?
link |
01:02:26.840
When was that invented?
link |
01:02:29.600
And poetic and biological ways of putting it,
link |
01:02:33.920
how do you describe predator prey relationship?
link |
01:02:37.400
Is it a beautiful dance or is it a violent atrocity?
link |
01:02:43.000
Well, I guess it's both, isn't it?
link |
01:02:44.360
I mean, when does it start?
link |
01:02:45.360
It starts in bacteria.
link |
01:02:46.920
You see these amazing predators.
link |
01:02:49.280
Della Vibrio is one that Lynn Margulis
link |
01:02:51.640
used to talk about a lot.
link |
01:02:53.760
It's got a kind of a drill piece
link |
01:02:55.600
that drills through the wall
link |
01:02:57.240
and the membrane of the bacterium.
link |
01:02:58.720
And then it effectively eats the bacterium
link |
01:03:00.560
from just inside the periplasmic space
link |
01:03:03.560
and makes copies of itself that way.
link |
01:03:04.960
So that's straight predation.
link |
01:03:06.360
There are predators among bacteria.
link |
01:03:08.360
So predation in that, sorry to interrupt,
link |
01:03:10.280
means you murder somebody
link |
01:03:12.560
and use their body as a resource in some way.
link |
01:03:17.600
Yeah.
link |
01:03:18.440
But it's not parasitic in that
link |
01:03:21.440
you need them to be still alive.
link |
01:03:23.400
No, no, I mean, predation is you kill them, really.
link |
01:03:26.360
You murder.
link |
01:03:27.200
Parasites, so you kind of live on them.
link |
01:03:30.320
Okay, so, but it seems the predator is the really popular.
link |
01:03:34.080
So what we see if we go back 560, 570 million years
link |
01:03:42.080
before the Cambrian explosion,
link |
01:03:44.200
there is what's known as the Ediacaran fauna,
link |
01:03:48.600
or sometimes they call Vendobionts,
link |
01:03:50.200
which is a lovely name.
link |
01:03:51.760
And it's not obvious that they're animals at all.
link |
01:03:55.680
They're stalked things.
link |
01:03:56.720
They often have fronds that look a lot like leaves
link |
01:03:59.200
with kind of fractal branching patterns on them.
link |
01:04:01.960
And the thing is, they're found,
link |
01:04:05.640
sometimes geologists can figure out the environment
link |
01:04:09.480
that they were in and say,
link |
01:04:10.840
this is more than 200 meters deep
link |
01:04:12.480
because there's no sign of any waves.
link |
01:04:14.560
There's no storm damage down here, this kind of thing.
link |
01:04:18.600
They were more than 200 meters deep,
link |
01:04:19.760
so they're definitely not photosynthetic.
link |
01:04:21.800
These are animals and they're filter feeders.
link |
01:04:25.400
And we know sponges and corals and things
link |
01:04:27.720
are filter feeding animals.
link |
01:04:29.040
They're stuck to the spot.
link |
01:04:30.560
And little bits of carbon that come their way,
link |
01:04:32.920
they filter it out and that's what they're eating.
link |
01:04:36.720
So no predation involved in this,
link |
01:04:38.480
beyond stuff just dies anyway.
link |
01:04:40.680
And it feels like a very gentle, rather beautiful,
link |
01:04:43.360
rather limited world, you might say.
link |
01:04:45.720
There's not a lot going on there.
link |
01:04:48.480
And something changes.
link |
01:04:51.720
Oxygen definitely changes during this period.
link |
01:04:53.920
Other things may have changed as well.
link |
01:04:55.360
But the next thing you really see in the fossil record
link |
01:04:58.280
is the Cambrian explosion.
link |
01:05:00.600
And what do we see there?
link |
01:05:02.080
We're now seeing animals that we would recognize.
link |
01:05:04.800
They've got eyes, they've got claws, they've got shells.
link |
01:05:07.760
They're plainly killing things or running away and hiding.
link |
01:05:14.440
And so we've gone from a rather gentle but limited world
link |
01:05:18.680
to a rather vicious, unpleasant world that we recognize
link |
01:05:23.080
and which leads to kind of arms races,
link |
01:05:27.520
evolutionary arms races, which again is something
link |
01:05:31.160
that when we think about a nuclear arms race,
link |
01:05:32.920
we think, Jesus, we don't want to go there.
link |
01:05:34.880
It's not done anybody any good.
link |
01:05:37.400
In some ways, maybe it does do good.
link |
01:05:40.160
I don't want to make an argument for nuclear arms.
link |
01:05:42.760
But predation as a mechanism forces organisms
link |
01:05:48.400
to adapt to change to be better to escape or to kill.
link |
01:05:52.320
If you need to eat, then you've got to eat.
link |
01:05:55.920
And a cheetah's not going to run at that speed
link |
01:05:57.840
unless it has to because the zebra is capable of escaping.
link |
01:06:03.640
So it leads to much greater feats of evolution
link |
01:06:07.840
than would ever have been possible without it.
link |
01:06:09.880
And in the end, to a much more beautiful world.
link |
01:06:12.680
And so it's not all bad by any means.
link |
01:06:17.840
But the thing is you can't have this
link |
01:06:19.320
if you don't have an oxygenated planet.
link |
01:06:21.080
Because it's all in the end, it's about how much energy
link |
01:06:24.120
can you extract from the food you eat.
link |
01:06:26.640
And if you don't have an oxygenated planet,
link |
01:06:28.360
you can get about 10% out, not much more than that.
link |
01:06:32.240
And if you've got an oxygenated planet,
link |
01:06:34.120
you can get about 40% out.
link |
01:06:35.960
And that means you can have,
link |
01:06:37.040
instead of having one or two trophic levels,
link |
01:06:40.440
you can have five or six trophic levels.
link |
01:06:42.760
And that means things can eat things
link |
01:06:44.360
that eat other things and so on.
link |
01:06:45.720
And you've gone to a level of ecological complexity,
link |
01:06:48.920
which is completely impossible in the absence of oxygen.
link |
01:06:51.720
This reminds me of the Hunter S. Thompson quote,
link |
01:06:54.400
that for every moment of triumph,
link |
01:06:56.840
for every instance of beauty, many souls must be trampled.
link |
01:07:02.040
The history of life on Earth, unfortunately,
link |
01:07:05.120
is that of violence.
link |
01:07:09.000
Just the trillions and trillions of multi cell organisms
link |
01:07:13.320
that were murdered in the struggle for survival.
link |
01:07:17.040
It's a sorry statement, but yes, it's basically true.
link |
01:07:20.360
And that somehow is a catalyst
link |
01:07:23.960
from an evolutionary perspective for creativity,
link |
01:07:26.220
for creating more and more complex organisms
link |
01:07:28.880
that are better and better at surviving.
link |
01:07:30.160
I mean, survival of the fittest,
link |
01:07:32.080
if you just go back to that old phrase,
link |
01:07:33.520
means death of the weakest.
link |
01:07:36.280
Now, what's fit, what's weak,
link |
01:07:38.480
these are terms that don't have much intrinsic meaning.
link |
01:07:41.400
But the thing is, evolution only happens because of death.
link |
01:07:45.280
One way to die is the constraints,
link |
01:07:49.000
the scarcity of the resources in the environment,
link |
01:07:52.160
but that seems to be not nearly as good of a mechanism
link |
01:07:56.280
for death than other creatures
link |
01:07:59.480
roaming about in the environment.
link |
01:08:01.480
When I say environment, I mean like the static environment,
link |
01:08:04.160
but then there's the dynamic environment
link |
01:08:05.880
of bigger things trying to eat you
link |
01:08:08.360
and use you for your energy.
link |
01:08:10.600
It forces you to come up with a solution
link |
01:08:13.280
to your specific problem that is inventive
link |
01:08:16.920
and is new and hasn't been done before.
link |
01:08:18.800
And so it forces, I mean, literally change,
link |
01:08:22.560
literally evolution on populations.
link |
01:08:26.000
They have to become different.
link |
01:08:27.400
And it's interesting that humans have channeled that
link |
01:08:30.900
into more, I mean, I guess what humans are doing
link |
01:08:34.220
is they're inventing more productive
link |
01:08:37.760
and safe ways of doing that.
link |
01:08:39.880
You know, this whole idea of morality
link |
01:08:41.520
and all those kinds of things,
link |
01:08:43.360
I think they ultimately lead to competition
link |
01:08:48.360
versus violence, because I think violence
link |
01:08:51.600
can have a cold, brutal, inefficient aspect to it.
link |
01:08:56.560
But if you channel that into more controlled competition
link |
01:09:01.280
in the space of ideas, in the space of approaches to life,
link |
01:09:05.480
maybe you can be even more productive than evolution is.
link |
01:09:10.280
Because evolution is very wasteful.
link |
01:09:12.200
Like the amount of murder required
link |
01:09:14.680
to really test a good idea,
link |
01:09:16.600
genetically speaking, is just a lot.
link |
01:09:19.520
Many, many, many generations.
link |
01:09:21.120
Morally, we cannot base society
link |
01:09:24.560
on the way that evolution works.
link |
01:09:26.280
That's an invention, right?
link |
01:09:27.280
But actually, in some respects we do,
link |
01:09:29.600
which is to say, this is how science works.
link |
01:09:31.440
We have competing hypotheses that have to get better,
link |
01:09:34.000
otherwise they die.
link |
01:09:35.360
It's the way that society works.
link |
01:09:36.640
You know, in ancient Greece, we had the Athens
link |
01:09:41.040
and Sparta and city states,
link |
01:09:42.520
and then we had the Renaissance and nation states,
link |
01:09:45.360
and universities compete with each other.
link |
01:09:48.400
Tremendous amount of companies competing
link |
01:09:50.560
with each other all the time.
link |
01:09:51.680
It drives innovation.
link |
01:09:55.080
And if we want to do it without all the death
link |
01:09:57.400
that we see in nature,
link |
01:09:59.040
then we have to have some kind of societal level control
link |
01:10:03.320
that says, well, there's some limits, guys,
link |
01:10:05.480
and these are what the limits are gonna be.
link |
01:10:07.240
And society as a whole has to say,
link |
01:10:08.760
right, we want to limit the amount of death here,
link |
01:10:10.920
so you can't do this and you can't do that.
link |
01:10:12.720
And you know, who makes up these rules,
link |
01:10:14.280
and how do we know?
link |
01:10:15.120
It's a tough thing, but it's basically
link |
01:10:16.960
trying to find a moral basis
link |
01:10:19.440
for avoiding the death of evolution and natural selection
link |
01:10:22.960
and keeping the innovation and the richness of it.
link |
01:10:27.400
And I forgot who said it, but that murder is illegal.
link |
01:10:31.840
Probably Kurt Vonnegut.
link |
01:10:33.200
Murder is illegal except when it's done
link |
01:10:35.440
to the sound of trumpets and at a large scale.
link |
01:10:38.240
So we still have wars.
link |
01:10:41.720
But we are struggling with this idea
link |
01:10:44.160
that murder is a bad thing.
link |
01:10:47.280
It's so interesting how we're channeling
link |
01:10:49.760
the best of the evolutionary imperative
link |
01:10:53.240
and trying to get rid of the stuff that's not productive.
link |
01:10:58.360
Trying to almost accelerate evolution.
link |
01:11:00.600
The same kind of thing that makes evolution creative.
link |
01:11:05.840
We're trying to use that.
link |
01:11:07.360
I think we naturally do it.
link |
01:11:08.640
I mean, I don't think we can help ourselves do it.
link |
01:11:10.640
And you know, capitalism as a form
link |
01:11:13.280
is basically about competition and differential rewards.
link |
01:11:17.200
But we, society, and you know, we have a,
link |
01:11:22.960
I keep using this word moral obligation,
link |
01:11:25.200
but you know, we cannot operate as a society
link |
01:11:28.680
if we go that way.
link |
01:11:29.800
It's interesting that we've had problems achieving balance.
link |
01:11:35.160
So for example, in the financial crash in 2009,
link |
01:11:39.320
do you let banks go to the wall or not?
link |
01:11:41.240
This kind of question.
link |
01:11:42.960
In evolution, certainly you let them go to the wall.
link |
01:11:45.040
And in that sense, you don't need the regulation
link |
01:11:47.840
because they just die.
link |
01:11:51.320
Whereas if we, as a society,
link |
01:11:53.840
think about what's required for society as a whole,
link |
01:11:56.320
then you don't necessarily let them go to the wall.
link |
01:11:59.440
In which case you then have to impose
link |
01:12:01.480
some kind of regulation that the bankers themselves will,
link |
01:12:05.440
in an evolutionary manner, exploit.
link |
01:12:08.160
Yeah, we've been struggling with this kind of idea
link |
01:12:11.360
of capitalism, the cold brutality of capitalism
link |
01:12:16.120
that seems to create so much beautiful things
link |
01:12:18.920
in this world.
link |
01:12:20.320
And then the ideals of communism
link |
01:12:23.200
that seem to create so much brutal destruction in history.
link |
01:12:26.640
We struggle with ideas of,
link |
01:12:28.720
well, maybe we didn't do it right.
link |
01:12:30.560
How can we do things better?
link |
01:12:31.760
And then the ideas are the things
link |
01:12:33.480
where we're playing with as opposed to people.
link |
01:12:35.960
If a PhD student has a bad idea,
link |
01:12:37.720
we don't shoot the PhD student.
link |
01:12:39.600
We just criticize their idea and hope they improve.
link |
01:12:42.080
You have a very humane lab.
link |
01:12:44.040
Yeah, I don't know how you guys do it.
link |
01:12:46.560
The way I run things, it's always life and death.
link |
01:12:49.360
Okay, so it is interesting about humans
link |
01:12:52.480
that there is an inner sense of morality
link |
01:12:54.760
which begs the question of how did homo sapiens evolve?
link |
01:13:02.440
If we think about the invention of,
link |
01:13:05.560
early invention of sex and early invention of predation,
link |
01:13:10.520
what was the thing invented to make humans?
link |
01:13:15.440
What would you say?
link |
01:13:17.160
I mean, I suppose a couple of things I'd say.
link |
01:13:19.120
Number one is you don't have to wind the clock back
link |
01:13:21.360
very far, five, six million years or so,
link |
01:13:24.160
and let it run forwards again.
link |
01:13:26.640
And the chances of humans as we know them
link |
01:13:29.000
is not necessarily that high.
link |
01:13:31.040
You know, imagine as an alien, you find planet Earth
link |
01:13:34.560
and it's got everything apart from humans on it.
link |
01:13:36.280
It's an amazing, wonderful, marvelous planet,
link |
01:13:39.360
but nothing that we would recognize
link |
01:13:41.320
as extremely intelligent life,
link |
01:13:43.640
kind of space faring civilization.
link |
01:13:45.840
So when we think about aliens,
link |
01:13:46.960
we're kind of after something like ourselves.
link |
01:13:49.760
We're after a space faring civilization.
link |
01:13:51.800
We're not after zebras and giraffes and lions and things,
link |
01:13:55.840
amazing though they are.
link |
01:13:57.720
But the additional kind of evolutionary steps
link |
01:14:01.280
to go from large, complex mammals, monkeys, let's say,
link |
01:14:06.120
to humans doesn't strike me as that long a distance.
link |
01:14:12.960
It's all about the brain.
link |
01:14:14.440
And where's the brain and morality coming from?
link |
01:14:17.040
It seems to me to be all about groups,
link |
01:14:19.880
human groups and interactions between groups.
link |
01:14:22.440
The collective intelligence of it.
link |
01:14:24.480
Yes, the interactions really.
link |
01:14:26.680
And there's a guy at UCL called Mark Thomas,
link |
01:14:30.080
who's done a lot of really beautiful work,
link |
01:14:32.000
I think, on this kind of question.
link |
01:14:33.560
So I talk to him every now and then,
link |
01:14:34.920
so my views are influenced by him.
link |
01:14:38.920
But a lot seems to depend on population density,
link |
01:14:43.080
that the more interactions you have going on
link |
01:14:45.520
between different groups, the more transfer of information,
link |
01:14:49.200
if you like, between groups,
link |
01:14:51.040
people moving from one group to another group,
link |
01:14:53.600
almost like lateral gene transfer in bacteria,
link |
01:14:57.160
the more expertise you're able to develop and maintain,
link |
01:15:01.000
the more culturally complex your society can become.
link |
01:15:04.480
And groups that have become detached,
link |
01:15:07.760
like on Easter Island, for example,
link |
01:15:09.240
very often degenerate in terms of the complexity
link |
01:15:12.480
of their civilization.
link |
01:15:13.560
Is that true for complex organisms in general?
link |
01:15:16.080
Population density is often productive.
link |
01:15:19.160
Really matters, but in human terms,
link |
01:15:23.080
I don't know what the actual factors were
link |
01:15:26.000
that were driving a large brain,
link |
01:15:28.600
but you can talk about fire, you can talk about tool use,
link |
01:15:32.880
you can talk about language,
link |
01:15:34.120
and none of them seem to correlate especially well
link |
01:15:36.720
with the actual known trajectory of human evolution
link |
01:15:39.480
in terms of cave art and these kind of things.
link |
01:15:42.760
That seems to work much better
link |
01:15:45.080
just with population density
link |
01:15:47.520
and number of interactions between different groups,
link |
01:15:51.200
all of which is really about human interactions,
link |
01:15:55.840
human human interactions and the complexity of those.
link |
01:15:58.600
But population density is the thing
link |
01:16:02.040
that increases the number of interactions,
link |
01:16:04.280
but then there must have been inventions
link |
01:16:09.280
forced by that number of interactions
link |
01:16:12.920
that actually led to humans.
link |
01:16:14.680
So like Richard Wrangham talks about that
link |
01:16:18.600
it's basically the beta males had to beat up the alpha male.
link |
01:16:22.040
So that's what collaboration looks like,
link |
01:16:23.760
is they, when you're living together,
link |
01:16:28.480
our early ancestors don't like the dictatorial aspect
link |
01:16:33.680
of a single individual at the top of a tribe.
link |
01:16:36.040
So they learned to collaborate
link |
01:16:38.520
how to basically create a democracy of sorts,
link |
01:16:42.800
a democracy that prevents, minimizes,
link |
01:16:45.200
or lessens the amount of violence,
link |
01:16:47.320
which essentially gives strength to the tribe
link |
01:16:50.640
and make the war between tribes versus the dictator.
link |
01:16:55.040
I mean, I think one of the most wonderful things
link |
01:16:57.280
about humans is we're all of those things.
link |
01:17:00.360
I mean, we are deeply social as a species
link |
01:17:03.720
and we're also deeply selfish.
link |
01:17:05.360
And it seems to me the conflict
link |
01:17:06.440
between capitalism and communism,
link |
01:17:08.400
it's really just two aspects of human nature,
link |
01:17:10.400
both of which are.
link |
01:17:11.240
We have both and we have a constant kind of vying
link |
01:17:15.120
between the two sides.
link |
01:17:16.080
We really do care about other people beyond our families,
link |
01:17:19.440
beyond our immediate people.
link |
01:17:21.120
We care about society and the society that we live in.
link |
01:17:24.600
And you could say that's a drawing
link |
01:17:27.120
towards socialism or communism.
link |
01:17:28.520
On the other side, we really do care about ourselves.
link |
01:17:30.720
We really do care about our families,
link |
01:17:32.120
about working for something that we gain from.
link |
01:17:34.760
And that's the capitalist side of it.
link |
01:17:35.960
They're both really deeply ingrained in human nature.
link |
01:17:38.880
In terms of violence and interactions between groups,
link |
01:17:43.040
yes, all this dynamic of,
link |
01:17:45.960
if you're interacting between groups,
link |
01:17:47.160
you can be certain that they're gonna be burning each other
link |
01:17:50.240
and all kinds of physical violent interactions as well,
link |
01:17:53.360
which will drive the kind of cleverness
link |
01:17:56.600
of how do you resist this?
link |
01:17:57.840
Let's build a tower.
link |
01:17:59.360
What are we gonna do to prevent being overrun
link |
01:18:02.640
by those marauding gangs from over there?
link |
01:18:06.240
And you look outside humans
link |
01:18:08.280
and you look at chimps and bonobos and so on,
link |
01:18:10.640
and they're very, very different structures to society.
link |
01:18:13.280
Chimps tend to have an aggressive alpha male type structure
link |
01:18:16.640
and bonobos, there's basically a female society
link |
01:18:21.000
where the males are predominantly excluded
link |
01:18:22.880
and only brought in at the behest of the female.
link |
01:18:25.600
We have a lot in common with both of those groups.
link |
01:18:29.280
And there's, again, tension there.
link |
01:18:31.080
And probably chimps, more violence,
link |
01:18:33.360
the bonobos, probably more sex.
link |
01:18:35.440
That's another tension.
link |
01:18:36.760
How serious do we wanna be?
link |
01:18:42.240
How much fun we wanna be?
link |
01:18:44.160
Asking for a friend again,
link |
01:18:45.960
what do you think happened to Neanderthals?
link |
01:18:47.920
What did we cheeky humans do to the Neanderthals,
link |
01:18:52.000
Homo sapiens?
link |
01:18:53.040
Do you think we murdered them?
link |
01:18:54.320
Was it, how do we murder them?
link |
01:18:56.760
How do we outcompete them?
link |
01:18:59.360
Or do we mate them?
link |
01:19:01.240
I don't know.
link |
01:19:02.120
I mean, I think there's unequivocal evidence
link |
01:19:04.400
that we mated with them.
link |
01:19:05.980
We always try to mate with everything.
link |
01:19:07.720
Yes, pretty much.
link |
01:19:09.460
There's some interesting,
link |
01:19:10.320
the first sequences that came along
link |
01:19:12.060
were in mitochondrial DNA.
link |
01:19:14.060
And that was back to about 2002 or thereabouts.
link |
01:19:18.520
What was found was that Neanderthal mitochondrial DNA
link |
01:19:21.240
was very different to human mitochondria.
link |
01:19:23.360
Oh, that's so interesting.
link |
01:19:24.200
You could do a clock on it
link |
01:19:25.040
and it said the divergent state
link |
01:19:26.600
was about 600,000 years ago or something like that.
link |
01:19:29.200
So not so long ago.
link |
01:19:31.040
And then the first full genomes were sequenced
link |
01:19:33.960
maybe 10 years after that.
link |
01:19:36.240
And they showed plenty of signs of mating between.
link |
01:19:39.600
So the mitochondrial DNA effectively says no mating.
link |
01:19:43.080
And the nuclear genes say, yeah, lots of mating.
link |
01:19:47.920
But we don't know.
link |
01:19:48.740
How's that possible?
link |
01:19:49.580
So can you explain the difference
link |
01:19:50.400
between mitochondrial DNA and nucleus?
link |
01:19:53.840
I've talked before about the mitochondria,
link |
01:19:55.580
which are the power packs in cells.
link |
01:19:57.400
These are the paired down control units is their DNA.
link |
01:20:01.400
So it's passed on by the mother only.
link |
01:20:05.000
And in the egg cell,
link |
01:20:07.140
we might have half a million copies of mitochondrial DNA.
link |
01:20:10.600
There's only 37 genes left and they do a,
link |
01:20:15.080
it's basically the control unit of energy production.
link |
01:20:17.200
That's what it's doing.
link |
01:20:18.480
It's a basic old school machine that does.
link |
01:20:21.720
And it's got genes that were considered
link |
01:20:23.300
to be effectively trivial
link |
01:20:24.880
because they did a very narrowly defined job,
link |
01:20:28.740
but they're not trivial in the sense
link |
01:20:30.360
that that narrowly defined job
link |
01:20:31.640
is about everything that is being alive.
link |
01:20:35.800
So they're much easier to sequence.
link |
01:20:38.160
You've got many more copies of these things
link |
01:20:39.760
and you can sequence them very quickly.
link |
01:20:42.120
But the problem is because they go down
link |
01:20:43.800
only the maternal line from mother to daughter,
link |
01:20:46.320
your mitochondrial DNA and mine is going nowhere.
link |
01:20:49.560
It doesn't matter.
link |
01:20:50.960
Any kids we have, they get their mother's mitochondrial DNA
link |
01:20:53.840
except in very, very rare and strange circumstances.
link |
01:20:59.520
And so it tells a different story
link |
01:21:02.280
and it's not a story which is easy to reconcile always.
link |
01:21:06.280
And what it seems to suggest to my mind at least
link |
01:21:10.040
is that there was one way traffic of genes
link |
01:21:13.840
probably going from humans into Neanderthals
link |
01:21:16.520
rather than the other way around.
link |
01:21:18.040
Why did the Neanderthals disappear?
link |
01:21:19.800
I don't know.
link |
01:21:20.800
I mean, I suspect that they were,
link |
01:21:23.640
I suspect they were probably less violent,
link |
01:21:25.600
less clever, less populous, less willing to fight.
link |
01:21:31.560
I don't know.
link |
01:21:32.520
I mean, I think it probably drove them to extinction
link |
01:21:34.760
at the margins of Europe.
link |
01:21:37.160
And it's interesting how much,
link |
01:21:39.080
if we ran Earth over and over again,
link |
01:21:41.440
how many of these branches of intelligent beings
link |
01:21:45.360
that have figured out some kind of
link |
01:21:49.640
how to leverage collective intelligence,
link |
01:21:52.560
which ones of them emerge?
link |
01:21:53.760
Which ones of them succeed?
link |
01:21:55.640
Is it the more violent ones?
link |
01:21:57.760
Is it the more isolated ones?
link |
01:22:01.320
Like what dynamics result in more productivity?
link |
01:22:03.760
And I suppose we'll never know.
link |
01:22:06.400
The more complex the organism,
link |
01:22:07.840
the harder it is to run the experiment in the lab.
link |
01:22:10.600
Yes.
link |
01:22:12.120
And in some respects, maybe it's best if we don't know.
link |
01:22:15.160
Yeah.
link |
01:22:16.000
The truth might be very painful.
link |
01:22:18.120
What about if we actually step back
link |
01:22:20.640
a couple of interesting things that we humans do?
link |
01:22:24.920
One is object manipulation and movement.
link |
01:22:28.840
And of course, movement was something that was done,
link |
01:22:32.080
that was another big invention,
link |
01:22:33.760
being able to move around the environment.
link |
01:22:36.080
And the other one is this sensory mechanism,
link |
01:22:39.400
how we sense the environment.
link |
01:22:41.040
One of the coolest high definition ones is vision.
link |
01:22:45.320
How big are those inventions
link |
01:22:47.120
in the history of life on Earth?
link |
01:22:50.840
Vision, movement, I mean, again, extremely important,
link |
01:22:55.040
going back to the origin of animals,
link |
01:22:56.760
the Cambrian explosion where suddenly you're seeing eyes
link |
01:22:59.560
in the fossil record.
link |
01:23:01.080
And you can, it's not necessarily, again,
link |
01:23:03.720
lots of people historically have said
link |
01:23:05.800
what use is half an eye?
link |
01:23:06.920
And you can go in a series of steps
link |
01:23:10.640
from a light sensitive spot on a flat piece of tissue
link |
01:23:17.240
to an eyeball with a lens and so on.
link |
01:23:20.360
If you assume no more than, I don't remember,
link |
01:23:23.080
this was a specific model that I have in mind,
link |
01:23:25.120
but it was 1% change or half a percent change
link |
01:23:28.480
for each generation.
link |
01:23:29.440
How long would it take to evolve an eye as we know it?
link |
01:23:31.560
And the answer is half a million years.
link |
01:23:34.000
It doesn't have to take long.
link |
01:23:35.560
That's not how evolution works.
link |
01:23:36.840
That's not an answer to the question.
link |
01:23:38.640
It just shows you can reconstruct the steps
link |
01:23:41.680
and you can work out roughly how it can work.
link |
01:23:44.600
So it's not that big a deal to evolve an eye,
link |
01:23:49.280
but once you have one, then there's nowhere to hide.
link |
01:23:51.960
And again, we're back to predator prey relationships.
link |
01:23:55.120
We're back to all the benefits
link |
01:23:56.360
that being able to see brings you.
link |
01:23:58.320
And if you think philosophically what bats are doing
link |
01:24:00.760
with eco location and so on, I have no idea,
link |
01:24:04.240
but I suspect that they form an image of the world
link |
01:24:06.440
in pretty much the same way that we do.
link |
01:24:07.960
It's just a matter of mental reconstruction.
link |
01:24:10.160
So I suppose the other thing about sight,
link |
01:24:11.880
there are single celled organisms that have got a lens
link |
01:24:17.320
and a retina and a cornea and so on.
link |
01:24:21.600
Basically they've got a camera type eye in a single cell.
link |
01:24:24.840
They don't have a brain.
link |
01:24:27.440
What they understand about their world
link |
01:24:29.680
is impossible to say, but they're capable of coming up
link |
01:24:32.680
with the same structures to do so.
link |
01:24:34.960
So I suppose then is that once you've got things like eyes,
link |
01:24:39.160
then you have a big driving pressure
link |
01:24:41.100
on the central nervous system
link |
01:24:42.440
to figure out what it all means.
link |
01:24:44.480
And then we come around to your other point
link |
01:24:45.720
about manipulation, sensory input, and so on
link |
01:24:48.000
about now you have a huge requirement
link |
01:24:52.800
to understand what your environment is and what it means
link |
01:24:55.080
and how it reacts and how you should run away
link |
01:24:57.120
and where you should stay put.
link |
01:24:59.200
Actually on that point, let me,
link |
01:25:00.480
I don't know if you know the work of Donald Hoffman,
link |
01:25:03.800
who uses the argument, the mechanism of evolution
link |
01:25:11.640
to say that there's not necessarily
link |
01:25:14.800
a strong evolutionary value to seeing the world as it is.
link |
01:25:23.280
So objective reality, that our perception actually
link |
01:25:26.880
is very different from what's objectively real.
link |
01:25:29.840
We're living inside an illusion
link |
01:25:32.240
and we're basically the entire set of species on earth,
link |
01:25:37.560
I think, I guess, are competing in a space
link |
01:25:40.200
that's an illusion that's distinct from,
link |
01:25:41.980
that's far away from physical reality as it is,
link |
01:25:45.360
as defined by physics.
link |
01:25:46.280
I'm not sure it's an illusion so much as a bubble.
link |
01:25:48.720
I mean, we have a sensory input,
link |
01:25:50.520
which is a fraction of what we could have
link |
01:25:51.960
a sensory input on, and we interpret it
link |
01:25:55.280
in terms of what's useful for us to know to stay alive.
link |
01:25:58.240
So yes, it's an illusion in that sense,
link |
01:26:00.720
but the tree is physically there.
link |
01:26:03.640
And if you walk into that tree, you know,
link |
01:26:06.320
that there is, it's not purely a delusion,
link |
01:26:08.240
there's some physical reality to it.
link |
01:26:10.360
So it's a sensory slice into reality as it is,
link |
01:26:15.140
but because it's just a slice,
link |
01:26:17.160
you're missing a big picture.
link |
01:26:18.840
But he says that that slice doesn't necessarily
link |
01:26:21.400
need to be a slice.
link |
01:26:23.080
It could be a complete fabrication
link |
01:26:25.800
that's just consistent amongst the species,
link |
01:26:28.440
which is an interesting, or at least it's a humbling
link |
01:26:32.780
realization that our perception is limited
link |
01:26:37.160
and our cognitive abilities are limited.
link |
01:26:40.520
And at least to me, it's argument from evolution,
link |
01:26:44.920
I don't know how much, how strong that is as an argument,
link |
01:26:49.380
but I do think that life can exist in the mind.
link |
01:26:54.380
In the same way that you can do a virtual reality video game
link |
01:26:59.580
and you can have a vibrant life inside that place
link |
01:27:02.300
and that place is not real in some sense,
link |
01:27:05.860
but you could still have a vibrant,
link |
01:27:07.180
all the same forces of evolution,
link |
01:27:08.860
all the same competition, the dynamics of between humans
link |
01:27:12.860
you can have, but I don't know if,
link |
01:27:19.500
I don't know if there's evidence for that being
link |
01:27:21.980
the thing that happened on earth.
link |
01:27:23.660
It seems that earth.
link |
01:27:25.100
I think in either environment, I wouldn't deny
link |
01:27:27.100
that you could have exactly the world that you talk about
link |
01:27:29.820
and it would be very difficult to,
link |
01:27:33.420
the idea in matrix movies and so on
link |
01:27:36.540
that the whole world is completely a construction
link |
01:27:42.180
and we're fundamentally deluded.
link |
01:27:43.900
It's difficult to say that's impossible or couldn't happen
link |
01:27:47.260
or, and certainly we construct in our minds
link |
01:27:51.160
what the outside world is, but we do it on input
link |
01:27:53.220
and that input, I would hesitate to say it's not real
link |
01:27:57.780
because it's precisely how we do understand the world.
link |
01:28:00.340
We have eyes, but if you keep someone in,
link |
01:28:04.100
apparently this kind of thing happens,
link |
01:28:06.060
someone kept in a dark room for five years
link |
01:28:08.560
or something like that, they never see properly again
link |
01:28:10.940
because the neural wiring that underpins
link |
01:28:15.220
how we interpret vision never developed.
link |
01:28:18.840
You need, when you watch a child develop,
link |
01:28:21.260
it walks into a table, it bangs his head on the table
link |
01:28:23.780
and it hurts and now you've got two inputs.
link |
01:28:28.100
You've got one pain from this sharp edge
link |
01:28:30.060
and number two, you probably, you've touched it
link |
01:28:32.300
and realized it's there, it's a sharp edge
link |
01:28:33.900
and you've got the visual input
link |
01:28:34.940
and you put the three things together and think,
link |
01:28:36.500
I don't wanna walk into a table again.
link |
01:28:38.360
So you're learning and it's a limited reality,
link |
01:28:42.420
but it's a true reality and if you don't learn
link |
01:28:44.260
that properly, then you will get eaten,
link |
01:28:45.740
you will get hit by a bus, you will not survive.
link |
01:28:48.740
And same, if you're in some kind of,
link |
01:28:53.420
let's say, computer construction of reality,
link |
01:28:55.940
I'm not in my ground here, but if you construct the laws
link |
01:28:59.180
that this is what reality is inside this,
link |
01:29:03.620
then you play by those laws.
link |
01:29:05.180
Yeah, I mean, as long as the laws are consistent.
link |
01:29:07.580
So just like you said in the lab,
link |
01:29:09.620
the interesting thing about the simulation question,
link |
01:29:12.540
yes, it's hard to know if we're living inside a simulation,
link |
01:29:15.480
but also, yes, it's possible to do these kinds
link |
01:29:18.580
of experiments in the lab now more and more.
link |
01:29:21.700
To me, the interesting question is,
link |
01:29:23.740
how realistic does a virtual reality game need to be
link |
01:29:28.140
for us to not be able to tell the difference?
link |
01:29:30.620
A more interesting question to me is,
link |
01:29:33.300
how realistic or interesting
link |
01:29:38.460
does a virtual reality world need to be
link |
01:29:40.660
in order for us to want to stay there forever
link |
01:29:43.460
or much longer than physical reality, prefer that place?
link |
01:29:47.900
And also prefer it not as we prefer hard drugs,
link |
01:29:52.140
but prefer it in a deep, meaningful way
link |
01:29:55.100
in the way we enjoy life.
link |
01:29:57.820
I mean, I suppose the issue with the matrix,
link |
01:30:00.460
I imagine that it's possible to dilute the mind sufficiently
link |
01:30:05.020
that you genuinely, in that way,
link |
01:30:07.000
do think that you are interacting with the real world
link |
01:30:10.780
when in fact the whole thing's a simulation.
link |
01:30:14.340
How good does a simulation need to be to be able to do that?
link |
01:30:17.260
Well, it needs to convince you
link |
01:30:21.380
that all your sensory input is correct and accurate
link |
01:30:24.140
and joins up and makes sense.
link |
01:30:26.620
Now, that sensory input is not something
link |
01:30:28.380
that we're born with.
link |
01:30:29.740
We're born with a sense of touch.
link |
01:30:31.660
We're born with eyes and so on,
link |
01:30:33.020
but we don't know how to use them.
link |
01:30:34.120
We don't know what to make of them.
link |
01:30:35.740
We go around, we bump into trees.
link |
01:30:37.460
We cry a lot.
link |
01:30:38.660
We're in pain a lot.
link |
01:30:39.620
We're basically booting up the system
link |
01:30:43.080
so that it can make head or tail
link |
01:30:45.340
of the sensory input that it's getting.
link |
01:30:47.580
And that sensory input's not just a one way flux of things.
link |
01:30:49.980
It's also, you have to walk into things.
link |
01:30:51.580
You have to hear things.
link |
01:30:52.420
You have to put it together.
link |
01:30:53.700
Now, if you've got just babies in the matrix
link |
01:30:58.140
who are slotted into this,
link |
01:30:59.940
I don't think they have that kind of sensory input.
link |
01:31:02.540
I don't think they would have any way
link |
01:31:03.740
to make sense of New York as a world that they're part of.
link |
01:31:08.420
The brain is just not developed in that way.
link |
01:31:10.740
Well, I can't make sense of New York
link |
01:31:12.380
in this physical reality either.
link |
01:31:13.920
But yeah, I mean, but you said pain
link |
01:31:16.300
and the walking into things.
link |
01:31:17.840
Well, you can create a pain signal.
link |
01:31:19.760
And as long as it's consistent,
link |
01:31:21.900
that certain things result in pain,
link |
01:31:23.860
you can start to construct a reality.
link |
01:31:25.860
There's some, maybe you disagree with this,
link |
01:31:28.460
but I think we are born almost with a desire
link |
01:31:33.300
to be convinced by our reality,
link |
01:31:35.820
like a desire to make sense of our reality.
link |
01:31:38.860
Oh, I'm sure we are, yes.
link |
01:31:40.240
So there's an imperative.
link |
01:31:41.140
So whatever that reality is given to us,
link |
01:31:43.980
like the table hurts, fire is hot.
link |
01:31:46.580
I think we wanna be diluted
link |
01:31:49.900
in the sense that we want to make a simple,
link |
01:31:53.100
like Einstein's simple theory of the thing around us.
link |
01:31:56.440
We want that simplicity.
link |
01:31:58.020
And so maybe the hunger for the simplicity
link |
01:32:02.220
is the thing that could be used
link |
01:32:03.860
to construct a pretty dumb simulation that tricks us.
link |
01:32:07.820
So maybe tricking humans
link |
01:32:09.100
doesn't require building a universe.
link |
01:32:11.500
No, I don't.
link |
01:32:12.580
I mean, this is not what I work on,
link |
01:32:14.500
so I don't know how close to it we are.
link |
01:32:15.900
I don't think anyone works on it.
link |
01:32:16.740
But I agree with you that, yeah,
link |
01:32:18.740
I'm not sure that it's a morally justifiable thing to do,
link |
01:32:21.980
but is it possible in principle?
link |
01:32:26.500
I think it would be very difficult,
link |
01:32:28.420
but I don't see why in principle it wouldn't be possible.
link |
01:32:31.540
And I agree with you that we try to understand the world.
link |
01:32:35.860
We try to integrate the sensory inputs that we have,
link |
01:32:38.060
and we try to come up with a hypothesis
link |
01:32:40.180
that explains what's going on.
link |
01:32:41.980
I think though that we have huge input
link |
01:32:46.260
from the social context that we're in.
link |
01:32:49.140
We don't do it by ourselves.
link |
01:32:50.500
We don't kind of blunder around in a universe by ourself
link |
01:32:53.500
and understand the whole thing.
link |
01:32:55.980
We're told by the people around us
link |
01:32:58.060
what things are and what they do,
link |
01:32:59.420
and language is coming in here and so on.
link |
01:33:01.680
So it would have to be an extremely impressive simulation
link |
01:33:05.300
to simulate all of that.
link |
01:33:08.240
Yeah, simulate all of that,
link |
01:33:10.340
including the social construct,
link |
01:33:12.100
the spread of ideas and the exchange of ideas.
link |
01:33:15.940
I don't know.
link |
01:33:16.780
But those questions are really important to understand
link |
01:33:18.660
as we become more and more digital creatures.
link |
01:33:22.060
It seems like the next step of evolution
link |
01:33:23.780
is us becoming all the same mechanisms we've talked about
link |
01:33:28.300
are becoming more and more plugged into the machine.
link |
01:33:31.860
We're becoming cyborgs.
link |
01:33:34.100
And there's an interesting interplay
link |
01:33:36.660
between wires and biology.
link |
01:33:40.420
Zeros and ones and the biological systems.
link |
01:33:43.500
And I don't think we'll have the luxury
link |
01:33:48.700
to see humans as disjoint from the technology
link |
01:33:51.180
we've created for much longer.
link |
01:33:53.500
We are an organism that's.
link |
01:33:56.540
Yeah, I mean, I agree with you.
link |
01:34:00.300
But we come really with this to consciousness.
link |
01:34:06.100
Yes.
link |
01:34:06.940
And is there a distinction there?
link |
01:34:08.180
Because what you're saying,
link |
01:34:09.620
the natural end point says we are indistinguishable,
link |
01:34:12.020
that if you are capable of building an AI,
link |
01:34:17.100
which is sufficiently close and similar
link |
01:34:19.700
that we merge with it,
link |
01:34:20.660
then to all intents and purposes,
link |
01:34:23.620
that AI is conscious as we know it.
link |
01:34:26.220
And I don't have a strong view, but I have a view.
link |
01:34:35.100
And I wrote about it in the epilogue to my last book,
link |
01:34:37.780
because 10 years ago,
link |
01:34:39.580
I wrote a chapter in a book called Life Ascending
link |
01:34:44.420
about consciousness.
link |
01:34:45.900
And the subtitle of Life Ascending
link |
01:34:47.380
was The 10 Great Inventions of Evolution.
link |
01:34:49.940
And I couldn't possibly write a book
link |
01:34:51.340
with a subtitle like that that did not include consciousness.
link |
01:34:54.540
And specifically consciousness
link |
01:34:56.820
as one of the great inventions.
link |
01:34:59.420
And it was in part because I was just curious to know more
link |
01:35:02.540
and I read more for that chapter.
link |
01:35:04.380
I never worked on it, but I've always,
link |
01:35:06.340
how can anyone not be interested in the question?
link |
01:35:09.220
And I was left with the feeling that A, nobody knows,
link |
01:35:13.220
and B, there are two main schools of thought out there
link |
01:35:18.260
with a big kind of skew in distribution.
link |
01:35:21.180
One of them says, oh, it's a property of matter.
link |
01:35:23.780
It's an unknown law of physics.
link |
01:35:26.300
Panpsychism, everything is conscious.
link |
01:35:28.180
The sun is conscious.
link |
01:35:29.100
It's just a matter of, or a rock is conscious.
link |
01:35:31.380
It's just a matter of how much.
link |
01:35:33.700
And I find that very unpersuasive.
link |
01:35:36.460
I can't say that it's wrong.
link |
01:35:37.740
It's just that I think we somehow can tell the difference
link |
01:35:41.380
between something that's living and something that's not.
link |
01:35:45.060
And then the other end is it's an emergent property
link |
01:35:48.820
of a very complex central nervous system.
link |
01:35:51.340
And I never quite understand what people mean
link |
01:35:56.340
by words like emergence.
link |
01:35:57.820
I mean, there are genuine examples,
link |
01:35:59.580
but I think we very often tend to use it
link |
01:36:03.740
to plaster over ignorance.
link |
01:36:08.020
As a biochemist, the question for me then was,
link |
01:36:10.580
okay, it's a concoction of a central nervous system.
link |
01:36:16.140
A depolarizing neuron gives rise to a feeling,
link |
01:36:20.260
to a feeling of pain, or to a feeling of love,
link |
01:36:24.660
or anger, or whatever it may be.
link |
01:36:27.700
So what is then a feeling in biophysical terms
link |
01:36:30.580
in the central nervous system?
link |
01:36:31.820
Which bit of the wiring gives rise to,
link |
01:36:34.780
and I've never seen anyone answer that question
link |
01:36:38.060
in a way that makes sense to me.
link |
01:36:41.220
And that's an important question to answer.
link |
01:36:43.700
I think if we want to understand consciousness,
link |
01:36:45.380
that's the only question to answer.
link |
01:36:47.180
Because certainly an AI is capable of out thinking,
link |
01:36:51.780
and it's only a matter of time.
link |
01:36:53.460
Maybe it's already happened.
link |
01:36:54.940
In terms of just information processing
link |
01:36:58.260
and computational skill,
link |
01:37:00.020
I don't think we have any problem in designing a mind
link |
01:37:04.220
which is at least the equal of the human mind.
link |
01:37:07.300
But in terms of what we value the most as humans,
link |
01:37:11.180
which is to say our feelings, our emotions,
link |
01:37:13.300
our sense of what the world is in a very personal way,
link |
01:37:20.140
that I think means as much or more to people
link |
01:37:23.540
than their information processing.
link |
01:37:24.900
And that's where I don't think that AI necessarily
link |
01:37:28.700
will become conscious, because I think
link |
01:37:31.460
it's the property of life.
link |
01:37:33.060
Well, let's talk about it more.
link |
01:37:34.220
You're an incredible writer, one of my favorite writers.
link |
01:37:36.820
So let me read from your latest book, Transformers,
link |
01:37:40.420
what you write about consciousness.
link |
01:37:42.760
I think therefore I am, said Descartes,
link |
01:37:46.180
is one of the most celebrated lines ever written.
link |
01:37:49.300
But what am I exactly?
link |
01:37:51.580
An artificial intelligence can think too, by definition,
link |
01:37:54.660
and therefore is, yet few of us could agree
link |
01:37:58.140
whether AI is capable in principle
link |
01:38:00.760
of anything resembling human emotions,
link |
01:38:03.180
of love or hate, fear and joy, of spiritual yearnings,
link |
01:38:08.500
for oneness or oblivion,
link |
01:38:10.660
or corporeal pangs of thirst and hunger.
link |
01:38:14.220
The problem is we don't know what emotions are,
link |
01:38:18.100
as you were saying.
link |
01:38:19.380
What is the feeling in physical terms?
link |
01:38:21.780
How does a discharging neuron give rise
link |
01:38:23.800
to a feeling of anything at all?
link |
01:38:25.680
This is the hard problem of consciousness,
link |
01:38:28.620
the seeming duality of mind and matter,
link |
01:38:31.180
the physical makeup of our innermost self.
link |
01:38:34.260
We can understand in principle
link |
01:38:35.640
how an extremely sophisticated parallel processing system
link |
01:38:38.780
could be capable of wondrous feats of intelligence,
link |
01:38:41.500
but we can't answer in principle
link |
01:38:44.140
whether such a supreme intelligence
link |
01:38:46.200
would experience joy or melancholy.
link |
01:38:49.160
What is the quantum of solace?
link |
01:38:52.980
I, speaking to the question of emergence,
link |
01:38:57.060
you know, there's just technical,
link |
01:39:00.900
there's an excellent paper on this recently
link |
01:39:03.820
about this kind of phase transition,
link |
01:39:08.140
emergence of performance in neural networks
link |
01:39:10.800
on the problem of NLP, natural language processing.
link |
01:39:14.980
So language models, there seems to be this question of size.
link |
01:39:19.460
At some point, there is a phase transition
link |
01:39:23.940
as you grow the size of the neural network.
link |
01:39:25.940
So the question is,
link |
01:39:27.300
that's sort of somewhat of a technical question
link |
01:39:29.980
that you can philosophize over.
link |
01:39:32.060
The technical question is,
link |
01:39:33.300
is there a size of a neural network
link |
01:39:35.740
that starts to be able to form the kind of representations
link |
01:39:39.140
that can capture a language,
link |
01:39:40.740
and therefore be able to, not just language,
link |
01:39:44.740
but linguistically capture knowledge
link |
01:39:47.120
that's sufficient to solve a lot of problems in language,
link |
01:39:50.940
like be able to have a conversation.
link |
01:39:52.580
And there seems to be not a gradual increase,
link |
01:39:55.780
but a phase transition.
link |
01:39:57.100
And they're trying to construct the science of where that is,
link |
01:40:01.200
like what is a good size of a neural network,
link |
01:40:03.620
and why does such a phase transition happen?
link |
01:40:05.900
Anyway, that sort of points to emergence,
link |
01:40:08.660
that there could be stages where a thing goes
link |
01:40:15.100
from being, oh, you're very intelligent toaster,
link |
01:40:20.180
to a toaster that's feeling sad today and turns away
link |
01:40:25.020
and looks out the window, sighing,
link |
01:40:29.180
having an existential crisis.
link |
01:40:30.660
Thinking of Marvin, the paranoid android.
link |
01:40:33.700
Marvin is simplistic because Marvin is just cranky.
link |
01:40:38.260
Yes.
link |
01:40:40.100
So easily programmed.
link |
01:40:41.580
Yeah, easily programmed, nonstop existential crisis.
link |
01:40:45.220
You're almost basically, what is it?
link |
01:40:47.300
Notes from Underground by Dostoevsky,
link |
01:40:48.820
like just constantly complaining about life.
link |
01:40:53.040
No, they're capturing the full rollercoaster
link |
01:40:57.140
of human emotion, the excitement, the bliss,
link |
01:41:00.140
the connection, the empathy and all that kind of stuff.
link |
01:41:03.940
And then the selfishness, the anger, the depression,
link |
01:41:09.100
all that kind of stuff.
link |
01:41:09.940
They're capturing all of that
link |
01:41:11.860
and be able to experience it deeply.
link |
01:41:14.420
Like it's the most important thing
link |
01:41:16.580
you could possibly experience today.
link |
01:41:18.540
The highest highs, the lowest lows, this is it.
link |
01:41:21.300
My life will be over.
link |
01:41:24.460
I cannot possibly go on that feeling.
link |
01:41:26.740
And then like after a nap, you're feeling amazing.
link |
01:41:30.580
That might be something that emerges.
link |
01:41:33.620
So why would a nap make an AI being feel better?
link |
01:41:42.580
First of all, we don't know that for a human either, right?
link |
01:41:45.220
But we do know that that's actually true
link |
01:41:47.620
for many people much of the time.
link |
01:41:48.980
You may be utterly depressed and you have a nap
link |
01:41:50.820
and you do in fact feel better, so.
link |
01:41:53.460
Oh, you are actually asking the technical question there,
link |
01:41:55.660
is there, so that's a very,
link |
01:41:57.940
there's a biological answer to that.
link |
01:41:59.980
And so the question is whether AI needs to have
link |
01:42:01.980
the same kind of attachments to its body,
link |
01:42:04.860
bodily function and preservation
link |
01:42:08.540
of the brain's successful function,
link |
01:42:13.180
self preservation essentially in some deep biological sense.
link |
01:42:17.060
I mean, to my mind, it comes back round
link |
01:42:19.940
to the problem we were talking about before
link |
01:42:21.660
about simulations and sensory input
link |
01:42:24.100
and learning what all of this stuff means
link |
01:42:28.580
and life and death,
link |
01:42:31.420
that biology unlike society has a death penalty
link |
01:42:35.100
over everything and natural selection works
link |
01:42:37.820
on that death penalty.
link |
01:42:38.980
That if you make this decision wrongly, you die.
link |
01:42:47.340
And the next generation is represented by beings
link |
01:42:50.780
that made a slightly different decision on balance.
link |
01:42:56.380
And that is something that's intrinsically
link |
01:43:00.980
difficult to simulate in all this richness, I would say.
link |
01:43:06.020
So what is?
link |
01:43:09.060
Death in all its richness.
link |
01:43:11.100
Yeah.
link |
01:43:12.060
Our relationship with death or the whole of it.
link |
01:43:16.580
So which when you say richness, of course,
link |
01:43:20.140
there's a lot in that.
link |
01:43:21.380
Yeah.
link |
01:43:22.220
Which is hard to simulate.
link |
01:43:23.860
What's part of the richness that's hard to simulate?
link |
01:43:27.660
I suppose the complexity of the environment
link |
01:43:31.020
and your position in that or the position
link |
01:43:33.340
of an organism in that environment,
link |
01:43:35.460
in the full richness of that environment
link |
01:43:37.540
over its entire life, over multiple generations
link |
01:43:40.620
with changes in gene sequence over those generations.
link |
01:43:44.220
So slight changes in the makeup of those individuals
link |
01:43:46.860
over generations.
link |
01:43:48.300
But if you take it back to the level of single cells,
link |
01:43:52.460
which I do in the book and ask how does a single cell
link |
01:43:59.340
in effect know it exists as a unit, as an entity?
link |
01:44:02.340
I mean, no, in inverted commas,
link |
01:44:03.980
obviously it doesn't know anything,
link |
01:44:07.100
but it acts as a unit and it acts
link |
01:44:09.060
with astonishing precision as a unit.
link |
01:44:14.660
And I had suggested that that's linked
link |
01:44:17.300
to the electrical fields on the membranes themselves
link |
01:44:19.860
and that they give some indication
link |
01:44:21.900
of how am I doing in relation to my environment
link |
01:44:24.340
as a kind of real time feedback on the world.
link |
01:44:28.340
And this is something physical,
link |
01:44:32.020
which can be selected over generations
link |
01:44:34.940
that if you get this wrong,
link |
01:44:39.180
it's linked with this set of circumstances
link |
01:44:42.300
that I've just, as an individual,
link |
01:44:45.500
I have a moment of blind panic and run
link |
01:44:49.140
as a bacterium or something.
link |
01:44:50.620
You have some electrical discharge that says blind panic
link |
01:44:54.180
and it runs whatever it may be.
link |
01:44:56.580
And you associate over generations, multiple generations
link |
01:44:59.820
that this electrical phase that I'm in now
link |
01:45:03.660
is associated with a response like that.
link |
01:45:07.100
And it's easy to see how feelings come in
link |
01:45:09.860
through the back door almost with that kind of giving real time
link |
01:45:17.700
feedback on your position in the world
link |
01:45:19.500
in relation to how am I doing.
link |
01:45:22.060
And then you complexify the system
link |
01:45:23.900
and yes, I have no problem with phase transition.
link |
01:45:27.780
And can all of this be done purely by the language,
link |
01:45:36.420
by the issues with how the system understands itself?
link |
01:45:42.620
Maybe it can, I honestly don't know.
link |
01:45:45.260
But the philosophers for a long time
link |
01:45:47.580
have talked about the possibility
link |
01:45:49.700
that you can have a zombie intelligence
link |
01:45:54.100
and that there are no feelings there,
link |
01:45:55.660
but everything else is the same.
link |
01:45:59.460
I mean, I have to throw this back to you really.
link |
01:46:01.460
How do you deal with the zombie intelligence?
link |
01:46:03.980
So first of all, I can see that from a biologist perspective,
link |
01:46:08.620
you think of all the complexities
link |
01:46:10.740
that led up to the human being.
link |
01:46:12.860
The entirety of the history of four billion years
link |
01:46:15.780
that in some deep sense integrated the human being
link |
01:46:18.860
into this environment.
link |
01:46:20.180
And that dance of the organism and the environment,
link |
01:46:25.020
you could see how emotions arise from that.
link |
01:46:27.380
And then emotions are deeply connected
link |
01:46:29.740
and creating a human experience.
link |
01:46:32.020
And from that, you mix in consciousness
link |
01:46:34.180
and the full mess of it, yeah.
link |
01:46:37.260
But from a perspective of an intelligent organism
link |
01:46:40.900
that's already here, like a baby that learns,
link |
01:46:45.220
it doesn't need to learn how to be a collection of cells
link |
01:46:49.420
or how to do all the things it needs to do.
link |
01:46:52.260
The basic function of a baby as it learns
link |
01:46:55.340
is to interact with its environment,
link |
01:46:57.380
to learn from its environment,
link |
01:46:58.620
to learn how to fit in to the social society,
link |
01:47:01.820
to like...
link |
01:47:03.180
And the basic response of the baby
link |
01:47:05.940
is to cry a lot of the time.
link |
01:47:07.100
To cry, well, to convince the humans to protect it
link |
01:47:12.540
or to discipline it, to teach it.
link |
01:47:14.940
I mean, we've developed a bunch of different tricks,
link |
01:47:18.780
how to get our parents to take care of us,
link |
01:47:22.100
to educate us, to teach us about the world.
link |
01:47:24.860
Also, we've constructed the world in such a way
link |
01:47:27.900
that it's safe enough for us to survive in
link |
01:47:30.380
and yet dangerous enough for learning the valuable lessons.
link |
01:47:32.780
Like the tables are still hard with corners,
link |
01:47:35.580
so it can still run into them.
link |
01:47:36.820
It hurts like how...
link |
01:47:38.740
So AI needs to solve that problem,
link |
01:47:41.660
not the problem of constructing
link |
01:47:43.060
this super complex organism that leads up...
link |
01:47:47.980
To run the whole...
link |
01:47:51.660
To make an apple pie, to build the whole universe,
link |
01:47:53.940
you need to build a whole universe.
link |
01:47:55.900
I think the zombie question is something
link |
01:48:01.780
I would leave to the philosophers.
link |
01:48:04.020
Because...
link |
01:48:08.260
And I will also leave to them the definition of love
link |
01:48:11.180
and what happens between two human beings
link |
01:48:14.900
when there's a magic that just grabs them.
link |
01:48:18.540
Like nothing else matters in the world
link |
01:48:20.700
and somehow you've been searching for this feeling,
link |
01:48:22.980
this moment, this person your whole life.
link |
01:48:25.260
That feeling, the philosophers can have a lot of fun
link |
01:48:29.540
with that one and also say that that's just...
link |
01:48:32.820
You can have a biological explanation,
link |
01:48:34.700
you can have all kinds of...
link |
01:48:35.740
It's all fake, it's actually...
link |
01:48:38.300
Ayn Rand will say it's all selfish.
link |
01:48:40.700
There's a lot of different interpretations.
link |
01:48:42.420
I'll leave it to the philosophers.
link |
01:48:43.620
The point is the feeling sure as hell feels very real.
link |
01:48:48.020
And if my toaster makes me feel
link |
01:48:51.860
like it's the only toaster in the world.
link |
01:48:55.740
And when I leave and I miss the toaster
link |
01:48:58.420
and when I come back, I'm excited to see the toaster
link |
01:49:01.420
and my life is meaningful and joyful
link |
01:49:03.980
and the friends I have around me get a better version of me
link |
01:49:08.100
because that toaster exists.
link |
01:49:10.740
That sure as hell feels like a conscious toaster.
link |
01:49:13.340
Is that psychologically different to having a dog?
link |
01:49:16.020
No.
link |
01:49:16.860
Because I mean most people would dispute
link |
01:49:19.260
whether we can say a dog...
link |
01:49:20.540
I would say a dog is undoubtedly conscious,
link |
01:49:22.220
but some people say it doesn't.
link |
01:49:24.060
But there's degrees of consciousness and so on,
link |
01:49:26.260
but people are definitely much more uncomfortable
link |
01:49:28.780
saying a toaster can be conscious than a dog.
link |
01:49:32.620
And there's still a deep connection.
link |
01:49:35.060
You could say our relationship with the dog
link |
01:49:37.860
has more to do with anthropomorphism.
link |
01:49:40.100
Like we kind of project the human being onto it.
link |
01:49:42.380
Maybe.
link |
01:49:43.220
We can do the same damn thing with a toaster.
link |
01:49:45.780
Yes, but you can look into the dog's eyes
link |
01:49:48.100
and you can see that it's sad,
link |
01:49:50.460
that it's delighted to see you again.
link |
01:49:52.500
I don't have a dog, by the way.
link |
01:49:53.900
It's not that I'm a dog person or a cat person.
link |
01:49:54.740
And dogs are actually incredibly good
link |
01:49:56.380
at using their eyes to do just that.
link |
01:49:59.460
They are.
link |
01:50:00.300
Now, I don't imagine that a dog is remotely
link |
01:50:02.660
as close to being intelligent as an AI intelligence,
link |
01:50:07.060
but it's certainly capable
link |
01:50:09.540
of communicating emotionally with us.
link |
01:50:11.980
But here's what I would venture to say.
link |
01:50:13.860
We tend to think because AI plays chess well
link |
01:50:17.140
and is able to fold proteins now well,
link |
01:50:19.700
that it's intelligent.
link |
01:50:21.020
I would argue that in order to communicate with humans,
link |
01:50:23.860
in order to have emotional intelligence,
link |
01:50:25.900
it actually requires another order
link |
01:50:27.420
of magnitude of intelligence.
link |
01:50:28.900
It's not easy to be flawed.
link |
01:50:34.100
Solving a mathematical puzzle is not the same
link |
01:50:38.380
as the full complexity of human to human interaction.
link |
01:50:42.060
That's actually, we humans just take for granted
link |
01:50:46.980
the things we're really good at.
link |
01:50:49.180
Nonstop, people tell me how shitty people are driving.
link |
01:50:52.700
No, humans are incredible at driving.
link |
01:50:56.580
Bipedal walking, walking, object manipulation.
link |
01:51:00.260
We're incredible at this.
link |
01:51:01.860
And so people tend to discount the things
link |
01:51:05.820
we all just take for granted.
link |
01:51:07.380
And one of those things that they discount
link |
01:51:10.180
is our ability, the dance of conversation
link |
01:51:13.580
and interaction with each other.
link |
01:51:15.340
The ability to morph ideas together.
link |
01:51:18.460
The ability to get angry at each other
link |
01:51:20.380
and then to miss each other.
link |
01:51:21.940
Like to create a tension that makes life fun
link |
01:51:24.980
and difficult and challenging in a way that's meaningful.
link |
01:51:28.300
That is a skill that's learned
link |
01:51:31.660
and AI would need to solve that problem.
link |
01:51:33.460
I mean, in some sense, what you're saying is
link |
01:51:37.020
AI cannot become meaningfully emotional, let's say,
link |
01:51:42.380
until it experiences some kind of internal conflict
link |
01:51:45.220
that is unable to reconcile these various aspects
link |
01:51:48.500
of reality or its reality with a decision to make.
link |
01:51:54.700
And then it feels sad, necessarily,
link |
01:51:56.820
because it doesn't know what to do.
link |
01:51:59.460
And I certainly can't dispute that.
link |
01:52:01.740
That may very well be how it works.
link |
01:52:03.700
I think the only way to find out is to do it.
link |
01:52:05.780
And to build it.
link |
01:52:06.700
Yeah, and leave it to the philosophers
link |
01:52:08.460
if it actually feels sad or not.
link |
01:52:11.220
The point is the robot will be sitting there alone
link |
01:52:13.860
having an internal conflict, an existential crisis,
link |
01:52:16.940
and that's required for it to have a deep,
link |
01:52:19.300
meaningful connection with another human being.
link |
01:52:21.560
Now, does it actually feel that?
link |
01:52:23.300
I don't know.
link |
01:52:24.140
But I'd like to throw something else at you,
link |
01:52:26.060
which troubles me on reading it.
link |
01:52:31.140
Noah Harari's book, 21 Lessons for the 21st Century.
link |
01:52:35.140
And he's written about this kind of thing
link |
01:52:36.520
on various occasions.
link |
01:52:38.440
And he sees biochemistry as an algorithm.
link |
01:52:40.740
And then AI will necessarily be able to hack that algorithm
link |
01:52:45.160
and do it better than humans.
link |
01:52:46.320
So there will be AI better at writing music
link |
01:52:48.800
that we appreciate than Mozart ever could,
link |
01:52:50.720
or writing better than Shakespeare ever did, and so on.
link |
01:52:53.040
Because biochemistry is algorithmic,
link |
01:52:55.560
and all you need to do is figure out
link |
01:52:56.880
which bits of the algorithm to play
link |
01:52:58.720
to make us feel good or bad or appreciate things.
link |
01:53:02.360
And as a biochemist, I find that argument
link |
01:53:05.680
an argument close to irrefutable and not very enjoyable.
link |
01:53:13.320
I don't like the sound of it.
link |
01:53:14.840
That's just my reaction as a human being.
link |
01:53:16.480
You might like the sound of it because that says
link |
01:53:18.160
that AI is capable of the same kind of emotional feelings
link |
01:53:23.440
about the world as we are,
link |
01:53:25.540
because the whole thing is an algorithm
link |
01:53:27.080
and you can program an algorithm, and there you are.
link |
01:53:31.160
He then has a peculiar final chapter
link |
01:53:33.520
where he talks about consciousness
link |
01:53:36.080
in rather separate terms.
link |
01:53:37.640
And he's talking about meditating and so on
link |
01:53:39.800
and getting in touch with his inner conscious.
link |
01:53:41.460
I don't meditate, I don't know anything about that.
link |
01:53:44.620
But he wrote in very different terms about it,
link |
01:53:48.160
as if somehow it's a way out of the algorithm.
link |
01:53:52.240
Now, it seems to me that consciousness in that sense
link |
01:53:56.100
is capable of scuppering the algorithm.
link |
01:53:58.740
I think in terms of the biochemical feedback loops
link |
01:54:01.880
and so on, it is undoubtedly algorithmic.
link |
01:54:04.840
But in terms of what we decide to do,
link |
01:54:07.880
it can be much more based on an emotion.
link |
01:54:14.840
We can just think, I don't care.
link |
01:54:16.960
I can't resolve this complex situation.
link |
01:54:20.280
I'm gonna do that.
link |
01:54:21.540
And that can be based on, in effect, a different currency,
link |
01:54:24.760
which is the currency of feelings and something
link |
01:54:27.040
where we don't have very much personal control over.
link |
01:54:29.980
And then it comes back around to you
link |
01:54:32.040
and what are you trying to get at with AI?
link |
01:54:35.360
Do we need to have some system
link |
01:54:38.060
which is capable of overriding a rational decision
link |
01:54:41.840
which cannot be made
link |
01:54:42.680
because there's too much conflicting information
link |
01:54:45.080
by effectively an emotional judgmental decision
link |
01:54:48.500
that just says, do this and see what happens.
link |
01:54:50.960
That's what consciousness is really doing in my view.
link |
01:54:53.400
Yeah, and the question is whether it's a different process
link |
01:54:56.480
or just a higher level process.
link |
01:54:59.020
I might, you know, the idea that biochemistry
link |
01:55:02.360
is an algorithm is, to me, an oversimplistic view.
link |
01:55:07.480
There's a lot of things that the moment you say it,
link |
01:55:13.320
it's irrefutable, but it simplifies.
link |
01:55:17.040
Of course.
link |
01:55:17.880
And in the process loses something fundamental.
link |
01:55:21.000
So for example, calling a universe
link |
01:55:23.480
and an information processing system, sure, yes.
link |
01:55:27.360
You could make that.
link |
01:55:29.720
It's a computer that's performing computations,
link |
01:55:32.160
but you're missing the process of the entropy
link |
01:55:40.720
somehow leading to pockets of complexity
link |
01:55:42.760
that creates these beautiful artifacts
link |
01:55:45.360
that are incredibly complex and they're like machines.
link |
01:55:48.880
And then those machines are through the process of evolution
link |
01:55:52.000
are constructing even further complexity.
link |
01:55:54.560
Like in calling universe information processing machine,
link |
01:55:59.860
you're missing those little local pockets
link |
01:56:03.000
and how difficult it is to create them.
link |
01:56:05.100
So the question to me is if biochemistry is an algorithm,
link |
01:56:07.880
how difficult is it to create a software system
link |
01:56:11.980
that runs the human body, which I think is incorrect.
link |
01:56:16.240
I think that is going to take so long.
link |
01:56:21.160
I mean, that's going to be centuries from now
link |
01:56:23.500
to be able to reconstruct the human.
link |
01:56:25.600
Now, what I would venture to say
link |
01:56:27.600
to get some of the magic of a human being
link |
01:56:30.400
with what we're saying with the emotions
link |
01:56:32.880
and the interactions and like a dog makes a smile
link |
01:56:36.400
and joyful and all those kinds of things
link |
01:56:38.200
that will come much sooner,
link |
01:56:39.640
but that doesn't require us to reverse engineer
link |
01:56:42.280
the algorithm of biochemistry.
link |
01:56:44.080
Yes, but the toaster is making you happy.
link |
01:56:47.680
Yes.
link |
01:56:48.640
It's not about whether you make the toaster happy.
link |
01:56:51.840
No, it has to be.
link |
01:56:52.680
It has to be.
link |
01:56:55.120
It has to be.
link |
01:56:56.160
The toaster has to be able to leave me happy.
link |
01:56:58.060
Yeah, but it's the toaster is the AI in this case
link |
01:57:00.080
is very intelligent.
link |
01:57:00.920
Yeah, the toaster has to be able to be unhappy and leave me.
link |
01:57:03.980
That's essential.
link |
01:57:06.360
Yeah.
link |
01:57:07.200
That's essential for my being able to miss the toaster.
link |
01:57:09.780
If the toaster is just my servant,
link |
01:57:12.240
that's not, or a provider of like services,
link |
01:57:17.720
like tells me the weather makes toast,
link |
01:57:20.440
that's not going to deep connection.
link |
01:57:22.760
It has to have internal conflict.
link |
01:57:24.900
You write about life and death.
link |
01:57:26.740
It has to be able to be conscious of its mortality
link |
01:57:30.940
and the finiteness of its existence.
link |
01:57:33.760
And that life is for temporary
link |
01:57:35.880
and therefore it needs to be more selective.
link |
01:57:38.000
One of the most moving moments in the movies
link |
01:57:41.040
from when I was a boy was the unplugging of Hal in 2001,
link |
01:57:45.080
where that was the death of a sentient being
link |
01:57:48.620
and Hal knew it.
link |
01:57:51.000
So I think we all kind of know
link |
01:57:55.260
that a sufficiently intelligent being
link |
01:58:00.140
is going to have some form of consciousness,
link |
01:58:02.760
but whether it would be like biological consciousness,
link |
01:58:06.820
I just don't know.
link |
01:58:07.660
And if you're thinking about how do we bring together,
link |
01:58:10.220
I mean, obviously we're going to interact
link |
01:58:13.320
more closely with AI,
link |
01:58:16.240
but is a dog really like a toaster
link |
01:58:21.640
or is there really some kind of difference there?
link |
01:58:25.680
You were talking about biochemistry is algorithmic,
link |
01:58:29.480
but it's not single algorithm
link |
01:58:31.400
and it's very complex, of course it is.
link |
01:58:33.180
So it may be that there are again conflicts
link |
01:58:35.840
in the circuits of biochemistry,
link |
01:58:37.160
but I have a feeling that the level of complexity
link |
01:58:40.980
of the total biochemical system
link |
01:58:43.280
at the level of a single cell is less complex
link |
01:58:45.560
than the level of neural networking in the human brain
link |
01:58:48.800
or in an AI.
link |
01:58:52.320
Well, I guess I assumed that we were including the brain
link |
01:58:55.760
in the biochemistry algorithm, because you have to...
link |
01:58:59.880
I would see that as a higher level of organization
link |
01:59:02.040
of neural networks.
link |
01:59:02.900
They're all using the same biochemical wiring
link |
01:59:04.880
within themselves.
link |
01:59:06.400
Yeah, but the human brain is not just neurons.
link |
01:59:09.740
It's the immune system.
link |
01:59:11.640
It's the whole package.
link |
01:59:13.840
I mean, to have a biochemical algorithm
link |
01:59:16.280
that runs an intelligent biological system,
link |
01:59:20.060
you have to include the whole damn thing.
link |
01:59:21.680
And it's pretty fascinating that it comes from like,
link |
01:59:24.440
from an embryo, like the whole, I mean, oh boy.
link |
01:59:29.080
I mean, if you can, what is a human being?
link |
01:59:33.220
Because it's just some code and then you built,
link |
01:59:36.320
and then that says DNA doesn't just tell you what to build,
link |
01:59:39.880
but how to build it.
link |
01:59:40.880
I mean, the thing is impressive.
link |
01:59:44.640
And the question is how difficult is it
link |
01:59:49.480
to reverse engineer the whole shebang?
link |
01:59:52.940
Very difficult.
link |
01:59:54.400
I would say it's,
link |
01:59:59.680
don't want to say impossible,
link |
02:00:01.200
but it's like, it's much easier to build a human
link |
02:00:05.380
than to reverse engineer, to build like a fake human,
link |
02:00:09.760
human like thing than to reverse engineer
link |
02:00:12.960
the entirety of the process of the evolution.
link |
02:00:15.960
I'm not sure if we are capable
link |
02:00:18.560
of reverse engineering the whole thing.
link |
02:00:21.160
If the human mind is capable of doing that.
link |
02:00:23.720
I mean, I wouldn't be a biologist if I wasn't trying,
link |
02:00:27.960
but I know I can't understand the whole problem.
link |
02:00:31.160
I'm just trying to understand the rudimentary outlines
link |
02:00:33.300
of the problem.
link |
02:00:35.700
There's another aspect though,
link |
02:00:37.280
you're talking about developing from a single cell
link |
02:00:39.200
to the human mind and all the part system,
link |
02:00:43.920
subsystems that are part of the immune system and so on.
link |
02:00:48.960
This is something that you'll talk about, I imagine,
link |
02:00:53.240
with Michael Levin, but so little is known about,
link |
02:01:00.720
you talk about reverse engineering,
link |
02:01:02.200
so little is known about the developmental pathways
link |
02:01:04.640
that go from a genome to going to a fully wired organism.
link |
02:01:09.160
And a lot of it seems to depend on the same
link |
02:01:11.360
in electrical interactions that I was talking about
link |
02:01:16.040
happening at the level of single cells
link |
02:01:17.720
and its interaction with the environment.
link |
02:01:19.200
There's a whole electrical field side to biology
link |
02:01:23.600
that is not yet written into any of the textbooks,
link |
02:01:27.040
which is about how does an embryo develop into
link |
02:01:29.600
or a single cell develop into these complex systems?
link |
02:01:32.520
What defines the head, what defines the immune system,
link |
02:01:35.040
what defines the brain and so on?
link |
02:01:37.160
That really is written in a language
link |
02:01:38.680
that we're only just beginning to understand
link |
02:01:40.360
and frankly, biologists, most biologists
link |
02:01:42.840
are still very reluctant to even get themselves tangled up
link |
02:01:47.280
in questions like electrical fields influencing development.
link |
02:01:51.680
It seems like mumbo jumbo to a lot of biologists
link |
02:01:54.520
and it should not be because this is
link |
02:01:55.800
the 21st century biology, this is where it's going.
link |
02:01:59.700
But we're not gonna reverse engineer a human being
link |
02:02:02.080
or the mind or any of these subsystems
link |
02:02:04.360
until we understand how this developmental process
link |
02:02:06.920
or how electricity in biology really works.
link |
02:02:10.000
And if it is linked with feelings
link |
02:02:13.640
and with consciousness and so on,
link |
02:02:15.920
that's the, I mean, in the meantime, we have to try,
link |
02:02:18.680
but I think that's where the answer lies.
link |
02:02:22.680
So you think it's possible that the key to things
link |
02:02:27.040
like consciousness are some of the more tricky aspects
link |
02:02:31.500
of cognition might lie in that early development,
link |
02:02:34.680
the interaction of electricity and biology.
link |
02:02:39.300
Electrical fields.
link |
02:02:40.840
But we already know the EEG and so on
link |
02:02:43.100
is telling us a lot about brain function,
link |
02:02:44.820
but we don't know which cells, which parts
link |
02:02:46.700
of a neural network is giving rise to the EEG.
link |
02:02:48.860
We don't know the basics.
link |
02:02:50.520
The assumption is, I mean, we know it's neural networks,
link |
02:02:53.640
we know it's multiple cells, hundreds or thousands
link |
02:02:55.740
of cells involved in it and we assume
link |
02:02:57.980
that it has to do with depolarization during action
link |
02:03:01.560
potentials and so on.
link |
02:03:03.480
But the mitochondria which are in there
link |
02:03:05.360
have much more membranes than the plasma membrane
link |
02:03:08.060
of the neuron and there's a much greater membrane potential
link |
02:03:10.760
and it's formed in parallel, very often parallel cristae,
link |
02:03:14.420
which are capable of reinforcing a field
link |
02:03:17.600
and generating fields over longer distances.
link |
02:03:21.120
And nobody knows if that plays a role
link |
02:03:23.300
in consciousness or not.
link |
02:03:24.600
There's reasons to argue that it could,
link |
02:03:26.400
but frankly we simply do not know
link |
02:03:28.900
and it's not taken into consideration.
link |
02:03:31.000
You look at the structure of the mitochondrial membranes
link |
02:03:35.260
in the brains of simple things like Drosophila,
link |
02:03:39.440
the fruit fly, and they have amazing structures.
link |
02:03:42.160
You can see lots of little rectangular things
link |
02:03:44.200
all lined up in amazing patterns.
link |
02:03:48.040
What are they doing?
link |
02:03:49.040
Why are they like that?
link |
02:03:49.920
We haven't the first clue.
link |
02:03:52.460
What do you think about organoids and brain organoids
link |
02:03:55.340
and so in a lab trying to study the development
link |
02:03:59.560
of these in the Petri dish development of organs.
link |
02:04:05.840
Do you think that's promising?
link |
02:04:06.860
Do you have to look at whole systems?
link |
02:04:08.640
I've never done anything like that.
link |
02:04:10.320
I don't know much about it.
link |
02:04:11.440
The people who I've talked to who do work on it
link |
02:04:13.640
say amazing things can happen
link |
02:04:15.160
and a bit of a brain grown in a dish
link |
02:04:18.480
is capable of experiencing some kind of feelings
link |
02:04:21.400
or even memories of its former brain.
link |
02:04:23.480
Again, I have a feeling that until we understand
link |
02:04:27.420
how to control the electrical fields
link |
02:04:29.540
that control development, we're not going to understand
link |
02:04:32.340
how to turn an organoid into a real functional system.
link |
02:04:36.620
But how do we get that understanding?
link |
02:04:38.500
It's so incredibly difficult.
link |
02:04:41.940
I mean, you would have to, I mean, one promising direction,
link |
02:04:44.700
I'd love to get your opinion on this.
link |
02:04:46.820
I don't know if you're familiar with the work of DeepMind
link |
02:04:49.020
and AlphaFold with protein folding and so on.
link |
02:04:52.180
Do you think it's possible
link |
02:04:54.060
that that will give us some breakthroughs in biology
link |
02:04:57.980
trying to basically simulate and model the behavior
link |
02:05:03.700
of trivial biological systems
link |
02:05:07.180
as they become complex biological systems?
link |
02:05:11.420
I'm sure it will.
link |
02:05:12.780
The interesting thing to me about protein folding
link |
02:05:16.340
is that for a long time, my understanding,
link |
02:05:19.780
this is not what I work on, so I may have got this wrong,
link |
02:05:21.580
but my understanding is that you take the sequence
link |
02:05:24.460
of a protein and you try to fold it.
link |
02:05:28.980
And there are multiple ways in which it can fold.
link |
02:05:31.020
And to come up with the correct conformation
link |
02:05:33.180
is not a very easy thing because you're doing it
link |
02:05:35.100
from first principles from a string of letters,
link |
02:05:37.420
which specify the string of amino acids.
link |
02:05:39.900
But what actually happens is when a protein
link |
02:05:43.460
is coming out of a ribosome,
link |
02:05:45.740
it's coming out of a charged tunnel
link |
02:05:47.940
and it's in a very specific environment,
link |
02:05:49.620
which is going to force this to go there now
link |
02:05:51.460
and then this one to go there and this one to come like that.
link |
02:05:53.340
And so you're forcing a specific conformational set
link |
02:05:55.900
of changes onto it as it comes out of the ribosome.
link |
02:05:58.420
So by the time it's fully emerged,
link |
02:06:00.060
it's already got its shape.
link |
02:06:01.860
And that shape depended on the immediate environment
link |
02:06:06.540
that it was emerging into one letter,
link |
02:06:09.100
one amino acid at a time.
link |
02:06:11.900
And I don't think that the field was looking at it that way.
link |
02:06:16.980
And if that's correct,
link |
02:06:18.740
then that's very characteristic of science,
link |
02:06:20.540
which is to say it asks very often the wrong question
link |
02:06:23.100
and then does really amazingly sophisticated analyses
link |
02:06:25.820
on something having never thought to actually think,
link |
02:06:27.860
well, what is biology doing?
link |
02:06:29.060
And biology is giving you a charged electrical environment
link |
02:06:31.860
that forces you to be this way.
link |
02:06:33.380
Now, did DeepMind come up through patterns
link |
02:06:37.940
with some answer that was like that?
link |
02:06:39.780
I've got absolutely no idea.
link |
02:06:41.820
It ought to be possible to deduce that
link |
02:06:44.420
from the shapes of proteins.
link |
02:06:46.500
It would require a much greater skill
link |
02:06:50.780
than the human mind has.
link |
02:06:52.820
But the human mind is capable of saying, well, hang on,
link |
02:06:55.140
let's look at this exit tunnel and try and work out
link |
02:06:57.080
what shape is this protein going to take?
link |
02:06:58.940
And we can figure that out.
link |
02:07:00.140
That's really interesting about the exit tunnel,
link |
02:07:01.580
but like sometimes we get lucky
link |
02:07:03.060
and just like in science, the simplified view
link |
02:07:08.540
or the static view will actually solve the problem for us.
link |
02:07:12.140
So in this case, it's very possible
link |
02:07:14.380
that the sequence of letters has a unique mapping
link |
02:07:17.220
to our structure without considering how it unraveled.
link |
02:07:21.440
So without considering the tunnel.
link |
02:07:23.740
And so that seems to be the case in this situation
link |
02:07:27.700
where the cool thing about proteins,
link |
02:07:29.700
all the different shapes they can possibly take,
link |
02:07:31.580
it actually seems to take very specific unique shapes
link |
02:07:35.300
given the sequence.
link |
02:07:36.660
That's forced on you by an exit tunnel.
link |
02:07:38.260
So the problem is actually much simpler than you thought.
link |
02:07:40.780
And then there's a whole army of proteins
link |
02:07:44.200
which change the conformational state, chaperone proteins.
link |
02:07:49.780
And they're only used when there's some presumably issue
link |
02:07:54.900
with how it came out of the exit tunnel
link |
02:07:56.500
and you wanna do it differently to that.
link |
02:07:58.020
So very often the chaperone proteins will go there
link |
02:08:00.780
and will influence the way in which it falls.
link |
02:08:03.520
So there's two ways of doing it.
link |
02:08:06.620
Either you can look at the structures
link |
02:08:09.280
and the sequences of all the proteins
link |
02:08:11.020
and you can apply an immense mind to it
link |
02:08:13.220
and figure out what the patterns are
link |
02:08:14.620
and figure out what happened.
link |
02:08:15.660
Or you can look at the actual situation where it is
link |
02:08:17.940
and say, well, hang on, it was actually quite simple.
link |
02:08:20.100
It's got a charged environment
link |
02:08:21.220
and then it's forced to come out this way.
link |
02:08:23.140
And then the question will be,
link |
02:08:24.040
well, do different ribosomes
link |
02:08:25.460
have different charged environments?
link |
02:08:27.060
What happens if a chaperone?
link |
02:08:28.780
You're asking a different set of questions
link |
02:08:30.460
to come to the same answer in a way
link |
02:08:31.780
which is telling you a much simpler story
link |
02:08:34.260
and explains why it is rather than saying it could be,
link |
02:08:37.800
this is one in a billion different possible conformational
link |
02:08:41.060
states that this protein could have.
link |
02:08:42.340
You're saying, well, it has this one
link |
02:08:43.460
because that was the only one it could take
link |
02:08:46.060
given its setting.
link |
02:08:48.340
Well, yeah, I mean, currently humans are very good
link |
02:08:51.100
at that kind of first principles thinking.
link |
02:08:52.940
I was stepping back, but I think AI is really good
link |
02:08:56.060
at collecting a huge amount of data
link |
02:08:58.980
and a huge amount of data of observation of planets
link |
02:09:01.980
and figure out that Earth is not at the center
link |
02:09:04.520
of the universe, that there's actually a sun,
link |
02:09:06.480
we're orbiting the sun.
link |
02:09:08.020
But then you can, as a human being, ask,
link |
02:09:10.060
well, how do solar systems come to be?
link |
02:09:15.240
What are the different forces that are required
link |
02:09:17.540
to make this kind of pattern emerge?
link |
02:09:19.940
And then you start to invent things like gravity.
link |
02:09:26.600
I mixed up the ordering of gravity,
link |
02:09:29.820
wasn't considered as a thing that connects planets,
link |
02:09:32.640
but we are able to think about those big picture things
link |
02:09:36.900
as human beings.
link |
02:09:38.300
AI is just very good to infer simple models
link |
02:09:42.260
from a huge amount of data.
link |
02:09:45.820
And the question is with biology,
link |
02:09:47.980
we kind of go back and forth at how we solve biology.
link |
02:09:50.980
Listen, protein folding was thought to be impossible
link |
02:09:54.500
to solve, and there's a lot of brilliant PhD students
link |
02:09:57.580
that worked one protein at a time
link |
02:09:59.460
trying to figure out the structure.
link |
02:10:00.900
And the fact that I was able to do that.
link |
02:10:03.540
Oh, I'm not knocking it at all,
link |
02:10:06.340
but I think that people have been asking
link |
02:10:08.940
the wrong question.
link |
02:10:09.780
But then, as the people start to ask
link |
02:10:13.500
better and bigger questions,
link |
02:10:17.220
the AI kind of enters the chat and says,
link |
02:10:20.980
I'll help you out with that.
link |
02:10:22.700
Can I give you another example for my own work?
link |
02:10:27.580
The risk of getting a disease as we get older,
link |
02:10:32.260
there are genetic aspects to it.
link |
02:10:35.260
If you spend your whole life overeating and smoking
link |
02:10:38.500
and whatever, that's a whole separate question.
link |
02:10:41.580
But there's a genetic side to the risk.
link |
02:10:43.260
And we know a few genes that increase your risk
link |
02:10:46.540
of certain things.
link |
02:10:47.380
And for probably 20 years now,
link |
02:10:49.660
people have been doing what's called GWAS,
link |
02:10:51.660
which is genome wide association studies.
link |
02:10:55.300
So you've effectively scanned the entire genome
link |
02:10:58.820
for any single nucleotide polymorphisms,
link |
02:11:02.220
which is to say a single letter change in one place,
link |
02:11:04.980
that has a higher association of being linked
link |
02:11:07.460
with a particular disease or not.
link |
02:11:09.260
And you can come up with thousands of these things
link |
02:11:10.940
across the genome.
link |
02:11:13.260
And if you add them all up and try and say,
link |
02:11:17.180
well, so do they add up to explain
link |
02:11:20.820
the known genetic risk of this disease?
link |
02:11:23.700
And the known genetic risk often comes from twin studies.
link |
02:11:26.180
And you can say that if this twin gets epilepsy,
link |
02:11:30.620
there's a 40 or 50% risk that the other twin,
link |
02:11:33.620
identical twin will also get epilepsy.
link |
02:11:35.820
Therefore, the genetic factor is about 50%.
link |
02:11:39.100
And so the gene similarities that you see
link |
02:11:43.020
should account for 50% of that known risk.
link |
02:11:46.420
Very often it accounts for less than a 10th
link |
02:11:49.220
of the known risk.
link |
02:11:50.820
And there's two possible explanations.
link |
02:11:52.980
And there's one which people tend to do,
link |
02:11:54.460
which is to say,
link |
02:11:55.300
ah, well, we don't have enough statistical power.
link |
02:11:58.180
If we, maybe there's a million,
link |
02:12:00.260
we've only found a thousand of them.
link |
02:12:01.620
But if we find the other million,
link |
02:12:02.860
they're weakly related,
link |
02:12:03.820
but there's a huge number of them.
link |
02:12:05.140
And so we'll account for that whole risk.
link |
02:12:07.420
Maybe there's a billion of them.
link |
02:12:11.500
So that's one way.
link |
02:12:12.780
The other way is to say,
link |
02:12:15.260
well, hang on a minute, you're missing a system here.
link |
02:12:17.020
That system is the mitochondrial DNA,
link |
02:12:19.140
which people tend to dismiss because it's small
link |
02:12:21.860
and it doesn't change very much.
link |
02:12:27.020
But a few single letter changes in that mitochondrial DNA,
link |
02:12:30.860
it controls some really basic processes.
link |
02:12:33.620
It controls not only all the energy
link |
02:12:36.540
that we need to live and to move around
link |
02:12:38.780
and do everything we do,
link |
02:12:39.700
but also biosynthesis to make the new building blocks
link |
02:12:44.380
to make new cells.
link |
02:12:47.420
And cancer cells very often kind of take over
link |
02:12:49.780
the mitochondria and rewire them
link |
02:12:52.100
so that instead of using them for making energy,
link |
02:12:54.620
they're effectively using them as precursors
link |
02:12:56.500
for the building blocks for biosynthesis.
link |
02:12:58.460
You need to make new amino acids,
link |
02:12:59.940
new nucleotides for DNA.
link |
02:13:01.380
You wanna make new lipids to make your membranes and so on.
link |
02:13:04.700
So they kind of rewire metabolism.
link |
02:13:06.940
Now, the problem is that we've got all these interactions
link |
02:13:10.220
between mitochondrial DNA and the genes in the nucleus
link |
02:13:13.420
that are overlooked completely
link |
02:13:15.380
because people throw away,
link |
02:13:16.660
literally throw away the mitochondrial genes.
link |
02:13:18.740
And we can see in fruit flies that they interact
link |
02:13:21.060
and produce big differences in risk.
link |
02:13:24.500
So you can set AI onto this question
link |
02:13:29.500
of exactly how many of these base changes there are.
link |
02:13:35.100
And this is one possible solution
link |
02:13:36.940
that maybe there are a million of them
link |
02:13:39.100
and it does account for the greatest part of the risk.
link |
02:13:41.220
Or the other one is they aren't, it's just not there.
link |
02:13:43.660
That actually the risk lies in something
link |
02:13:45.300
you weren't even looking at.
link |
02:13:47.140
And this is where human intuition is very important.
link |
02:13:50.860
And just this feeling that, well, I'm working on this
link |
02:13:53.580
and I think it's important and I'm bloody minded about it.
link |
02:13:56.220
And in the end, some people are right.
link |
02:13:57.580
It turns out that it was important.
link |
02:14:00.180
Can you get AI to do that, to be bloody minded?
link |
02:14:03.180
And that, hang on a minute,
link |
02:14:06.620
you might be missing a whole other system here
link |
02:14:09.340
that's much bigger.
link |
02:14:11.140
That's the moment of discovery of scientific revolution.
link |
02:14:17.500
I'm giving up on saying AI can't do something.
link |
02:14:22.260
I've said it enough times about enough things.
link |
02:14:25.220
I think there's been a lot of progress.
link |
02:14:27.460
And instead I'm excited by the possibility
link |
02:14:30.220
of AI helping humans.
link |
02:14:31.420
But at the same time, just like I said,
link |
02:14:34.420
we seem to dismiss the power of humans.
link |
02:14:37.380
Yes, yes.
link |
02:14:38.460
Like we're so limited in so many ways
link |
02:14:43.900
that we kind of, in what we feel like dumb ways,
link |
02:14:48.540
like we're not strong, we're kind of our attention,
link |
02:14:53.540
our attention, our memory is limited.
link |
02:14:57.060
Our ability to focus on things is limited
link |
02:15:00.260
in our own perception of what limited is.
link |
02:15:02.740
But that actually, there's an incredible computer
link |
02:15:05.460
behind the whole thing that makes this whole system work.
link |
02:15:08.900
Our ability to interact with the environment,
link |
02:15:11.860
to reason about the environment.
link |
02:15:13.300
There's magic there.
link |
02:15:14.940
And I'm hopeful that AI can capture
link |
02:15:17.340
some of that same magic.
link |
02:15:18.740
But that magic is not gonna look like
link |
02:15:20.820
Deep Blue playing chess.
link |
02:15:22.460
No, it's going to be more interesting.
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02:15:24.740
But I don't think it's gonna look
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02:15:25.940
like pattern finding either.
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02:15:27.980
I mean, that's essentially what you're telling me.
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02:15:29.620
It does very well at the moment.
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02:15:30.740
And my point is it works very well
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02:15:33.020
where you're looking for the right pattern.
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02:15:36.180
But we are storytelling animals
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02:15:38.540
and the hypothesis is a story.
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02:15:40.860
It's a testable story.
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02:15:42.500
But a new hypothesis is a leap into the unknown
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02:15:47.180
and it's a new story basically.
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02:15:48.460
And it says this leads to this leads to that.
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02:15:51.020
It's a causal set of storytelling.
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02:15:54.940
It's also possible that the leap into the unknown
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02:15:57.420
has a pattern of its own.
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02:15:58.660
Yes, it is.
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02:15:59.740
And it's possible that it's learnable.
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02:16:02.500
I'm sure it is.
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02:16:04.260
There's a nice book by Arthur Kessler
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02:16:06.820
on the nature of creativity.
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02:16:11.260
And he likens it to a joke where the punchline goes off
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02:16:13.980
in a completely unexpected direction
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02:16:15.580
and says that this is the basis of human creativity.
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02:16:18.500
That some creative switch of direction
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02:16:21.500
to an unexpected place is similar to a joke.
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02:16:25.020
I'm not saying that's how it works,
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02:16:26.300
but it's a nice idea and there must be some truth in it.
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02:16:30.740
And it's one of these,
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02:16:32.340
most of the stories we tell are probably the wrong story
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02:16:34.900
and probably going nowhere and probably not helpful.
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02:16:37.580
And we definitely don't do as well
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02:16:39.820
at seeing patterns in things.
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02:16:41.700
But some of the most enjoyable human aspects
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02:16:44.380
is finding a new story that goes to an unexpected place.
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02:16:47.660
And again, these are all aspects
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02:16:48.940
of what being human means to me.
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02:16:52.580
And maybe these are all things
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02:16:53.820
that AI figures out for itself,
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02:16:55.780
or maybe they're just aspects.
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02:16:58.020
But I just have the feeling sometimes
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02:17:00.300
that the people who are trying to understand
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02:17:04.860
what we are like,
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02:17:08.780
if we wish to craft an AI system
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02:17:10.620
which is somehow human like,
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02:17:12.740
that we don't have a firm enough grasp
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02:17:16.500
of what humans really are like in terms of how we are built.
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02:17:21.460
But we get a better, better understanding of that.
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02:17:25.020
I agree with you completely.
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02:17:26.620
We try to build a thing and then we go,
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02:17:29.300
hang on a minute, there's another system here.
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02:17:33.060
And that's actually the attempt to build AI
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02:17:35.900
that's human like,
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02:17:36.980
is getting us to a deeper understanding of human beings.
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02:17:39.940
The funny thing that I recently talked to Magnus Carlsen,
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02:17:42.900
why they consider to be the greatest chess player
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02:17:44.700
of all time.
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02:17:46.620
And he talked about AlphaZero,
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02:17:48.540
which is a system from DeepMind that plays chess.
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02:17:51.620
And he had a funny comment.
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02:17:55.260
He has a kind of dry sense of humor.
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02:17:57.620
But he was extremely impressed
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02:17:59.460
when he first saw AlphaZero play.
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02:18:02.100
And he said that it did a lot of things
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02:18:04.620
that could easily be mistaken for creativity.
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02:18:07.460
So he like, as a typical human,
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02:18:12.140
refused to give the system sort of its due.
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02:18:16.860
Because he came up with a lot of things
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02:18:18.540
that a lot of people are extremely impressed by.
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02:18:22.620
Not just the sheer calculation,
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