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Manolis Kellis: Human Genome and Evolutionary Dynamics | Lex Fridman Podcast #113


small model | large model

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The following is a conversation with Manolis Kellis.
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He's a professor at MIT and head
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of the MIT Computational Biology Group.
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He's interested in understanding the human genome
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from a computational, evolutionary, biological,
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and other cross disciplinary perspectives.
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He has more big, impactful papers and awards
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than I can list, but most importantly,
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he's a kind, curious, brilliant human being,
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and just someone I really enjoy talking to.
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His passion for science and life in general is contagious.
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The hours honestly flew by,
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and I'm sure we'll talk again on this podcast soon.
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And now, here's my conversation with Manolis Kellis.
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What to you is the most beautiful aspect
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of the human genome?
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Don't get me started.
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So. We've got time.
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The first answer is that the beauty of genomes
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transcends humanity.
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So it's not just about the human genome.
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Genomes in general are amazingly beautiful.
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And again, I'm obviously biased.
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So in my view, the way that I like to introduce
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the human genome and the way that I like to introduce
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genomics to my class is by telling them,
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you know, we're not the inventors
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of the first digital computer.
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We are the descendants of the first digital computer.
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Basically, life is digital.
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And that's absolutely beautiful about life.
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The fact that at every replication step,
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you don't lose any information
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because that information is digital.
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If it was analog, if it was just sprouting concentrations,
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you'd lose it after a few generations.
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It would just dissolve away.
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And that's what the ancients
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didn't understand about inheritance.
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The first person to understand digital inheritance
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was Mendel, of course.
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And his theory, in fact, stayed in a bookshelf
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for like 50 years while Darwin was getting famous
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about natural selection.
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But the missing component was this digital inheritance,
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the mechanism of evolution that Mendel had discovered.
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So that aspect in my view is the most beautiful aspect
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but it transcends all of life.
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And can you elaborate maybe the inheritance part?
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What was the key thing that the ancients didn't understand?
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So the very theory of inheritance as discrete units,
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throughout the life of Mendel and well after he's writing,
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people thought that his P experiments
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were just a little fluke,
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that they were just a little exception
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that would normally not even apply to humans,
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that basically what they saw
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is this continuum of eye color,
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this continuum of skin color,
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this continuum of hair color,
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this continuum of height.
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And all of these continuums did not fit
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with a discrete type of inheritance
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that Mendel was describing.
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But what's unique about genomics
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and what's unique about the genome
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is really that there are two copies
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and that you get a combination of these.
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But for every trait,
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there are dozens of contributing variables.
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And it was only Ronald Fisher in the 20th century
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that basically recognized that even five Mendelian traits
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would add up to a continuum like inheritance pattern.
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And he wrote a series of papers
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that still are very relevant today
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about sort of this Mendelian inheritance
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of continuum like traits.
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And I think that that was the missing step in inheritance.
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So well before the discovery of the structure of DNA,
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which is again, another amazingly beautiful aspect,
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the double helix,
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what I like to call the most noble molecule of our time,
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holds within it the secret of that discrete inheritance,
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but the conceptualization of discrete elements
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is something that precedes that.
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So even though it's discrete,
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when it materializes itself into actual traits that we see,
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it can be continuous.
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Basically arbitrarily rich and complex.
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So if you have five genes that contribute to human height,
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and there aren't five, there's a thousand.
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If there's only five genes
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and you inherit some combination of them,
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and every one makes you two inches taller
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or two inches shorter,
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it'll look like a continuous trait.
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But instead of five, there are thousands.
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And every one of them contributes to less than one millimeter.
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We change in height more during the day
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than each of these genetic variants contributes.
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So by the evening, you're shorter than you walk up with.
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Isn't that weird then
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that we're not more different than we are?
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Why are we all so similar
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if there's so much possibility to be different?
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Yeah, so there are selective advantages to being medium.
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If you're extremely tall or extremely short,
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you run into selective disadvantages.
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So you have trouble breathing, you have trouble running,
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you have trouble sitting if you're too tall.
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If you're too short, you might, I don't know,
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have other selective pressures are acting against that.
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If you look at natural history of human population,
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there's actually selection for height in Northern Europe
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and selection against height in Southern Europe.
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So there might actually be advantages
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to actually being not super tall.
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And if you look across the entire human population,
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for many, many traits,
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there's a lot of push towards the middle.
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Balancing selection is the usual term
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for selection that sort of seeks to not be extreme
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and to sort of have a combination of alleles
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that sort of keep recombining.
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And if you look at mate selection,
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super, super tall people
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will not tend to sort of marry super, super tall people.
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Very often you see these couples
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that are kind of compensating for each other.
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And the best predictor of the kid's age
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is very often just take the average of the two parents
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and then adjust for sex and boom, you get it.
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It's extremely heritable.
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Let me ask, you kind of took a step back to the genome
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outside of just humans,
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but is there something that you find beautiful
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about the human genome specifically?
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So I think the genome,
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if more people understood the beauty of the human genome,
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there would be so many fewer wars,
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so much less anger in the world.
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I mean, what's really beautiful about the human genome
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is really the variation
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that teaches us both about individuality
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and about similarity.
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So any two people on the planet are 99.9% identical.
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How can you fight with someone who's 99.9% identical to you?
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It's just counterintuitive.
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And yet any two siblings of the same parents
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differ in millions of locations.
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So every one of them is basically two to the million unique
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from any pair of parents,
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let alone any two random parents on the planet.
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So that's, I think, something that teaches us
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about sort of the nature of humanity in many ways,
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that every one of us is as unique as any star
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and way more unique in actually many ways.
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And yet we're all brothers and sisters.
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Yeah, just like stars, most of it is just fusion reactions.
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Yeah, you only have a few parameters to describe stars.
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Mass, size, initial size, and stage of life.
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Whereas for humans, it's thousands of parameters
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scattered across our genome.
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So the other thing that makes humans unique,
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the other things that makes inheritance unique in humans
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is that most species inherit things vertically.
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Basically instinct is a huge part of their behavior.
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The way that, I mean, with my kids,
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we've been watching this nest of birds
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with two little eggs outside our window
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for the last few months,
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for the last few weeks as they've been growing.
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And there's so much behavior that's hard coded.
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Birds don't just learn as they grow.
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There's no culture.
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Like a bird that's born in Boston
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will be the same as a bird that's born in California.
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So there's not as much inheritance of ideas, of customs.
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A lot of it is hard coding in their genome.
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What's really beautiful about the human genome
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is that if you take a person from today
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and you place them back in ancient Egypt,
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or if you take a person from ancient Egypt
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and you place them here today,
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they will grow up to be completely normal.
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That is not genetics.
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This is the other type of inheritance in humans.
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So on one hand, we have the genetic inheritance,
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which is vertical from your parents down.
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On the other hand, we have horizontal inheritance,
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which is the ideas that are built up at every generation
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are horizontally transmitted.
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And the huge amount of time
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that we spend in educating ourselves,
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a concept known as neoteny,
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neo for newborn and then teny for holding.
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So if you look at humans,
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I mean, the little birds that were eggs two weeks ago,
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and now one of them has already flown off.
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The other one's ready to fly off.
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In two weeks, they're ready to just fend for themselves.
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Humans, 16 years, 18 years, 24, getting out of college.
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I'm still learning.
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So that's so fascinating,
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this picture of a vertical and the horizontal.
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When you talk about the horizontal,
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is it in the realm of ideas?
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Exactly.
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Okay, so it's the actual social interactions.
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That's exactly right.
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That's exactly right.
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So basically the concept of neoteny
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is that you spend acquiring characteristics
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from your environment
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in an extremely malleable state of your brain
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and the wiring of your brain for a long period of your life.
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Compared to primates, we are useless.
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You take any primate at seven weeks
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and any human at seven weeks, we lose the battle.
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But at 18 years, you know, all bets are off.
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Like we basically, our brain continues to develop
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in an extremely malleable form till very late.
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And this is what allows education.
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This is what allows the person from Egypt
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to do extremely well now.
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And the reason for that is that the wiring of our brain
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and the development of that wiring is actually delayed.
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So, you know, the longer you delay that,
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the more opportunity you have to pass on knowledge,
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to pass on concepts, ideals, ideas
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from the parents to the child.
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And what's really absolutely beautiful about humans today
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is that that lateral transfer of ideas and culture
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is not just from uncles and aunts and teachers at school,
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but it's from Wikipedia and review articles on the web
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and thousands of journals
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that are sort of putting out information for free
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and podcasts and videocasts and all of that stuff
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where you can basically learn about any topic,
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pretty much everything that would be in any
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super advanced textbook in a matter of days,
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instead of having to go to the library of Alexandria
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and sail there to read three books
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and then sail for another few days to get to Athens
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and et cetera, et cetera, et cetera.
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So the democratization of knowledge
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and the spread, the speed of spread of knowledge
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is what defines, I think, the human inheritance pattern.
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So you sound excited about it, are you also a little bit
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afraid or are you more excited by the power
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of this kind of distributed spread of information?
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So you put it very kindly that most people
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are kind of using the internet and looking Wikipedia,
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reading articles, reading papers and so on,
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but if we're honest, most people online,
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especially when they're younger,
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probably looking at five second clips on TikTok
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or whatever the new social network is,
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are you, given this power of horizontal inheritance,
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are you optimistic or a little bit pessimistic
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about this new effect of the internet
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and democratization of knowledge on our,
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what would you call this, this genome,
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would you use the term genome, by the way, for this?
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00:15:31.880
Yeah, I think we use the genome to talk about DNA,
link |
00:15:36.200
but very often we say, I'm Greek,
link |
00:15:38.960
so people ask me, hey, what's in the Greek genome?
link |
00:15:40.760
And I'm like, well, yeah, what's in the Greek genome
link |
00:15:42.800
is both our genes and also our ideas
link |
00:15:44.760
and our ideals and our culture.
link |
00:15:46.640
So the poetic meaning of the word.
link |
00:15:48.240
Exactly, exactly, yeah.
link |
00:15:50.080
So I think that there's a beauty
link |
00:15:55.960
to the democratization of knowledge,
link |
00:15:57.720
the fact that you can reach as many people
link |
00:16:00.200
as any other person on the planet
link |
00:16:02.800
and it's not who you are,
link |
00:16:04.280
it's really your ideas that matter,
link |
00:16:06.640
is a beautiful aspect of the internet.
link |
00:16:11.880
I think there's, of course, a danger of my ignorance
link |
00:16:15.560
is as important as your expertise.
link |
00:16:18.240
The fact that with this democratization
link |
00:16:21.360
comes the abolishment of respecting expertise.
link |
00:16:25.120
Just because you've spent 10,000 hours of your life
link |
00:16:28.880
studying, I don't know, human brain circuitry,
link |
00:16:33.320
why should I trust you?
link |
00:16:34.160
I'm just gonna make up my own theories
link |
00:16:35.640
and they'll be just as good as yours,
link |
00:16:37.240
is an attitude that sort of counteracts
link |
00:16:39.640
the beauty of the democratization.
link |
00:16:42.480
And I think that within our educational system
link |
00:16:47.400
and within the upbringing of our children,
link |
00:16:49.720
we have to not only teach them knowledge,
link |
00:16:52.320
but we have to teach them the means to get to knowledge.
link |
00:16:55.760
And that, it's very similar to sort of you fish,
link |
00:16:59.320
you catch a fish for a man for one day,
link |
00:17:01.400
you fed them for one day, you teach them how to fish,
link |
00:17:03.880
you fed them for the rest of their life.
link |
00:17:05.560
So instead of just gathering the knowledge
link |
00:17:07.640
they need for any one task,
link |
00:17:09.480
we can just tell them, all right,
link |
00:17:11.120
here's how you Google it,
link |
00:17:12.520
here's how you figure out what's real and what's not,
link |
00:17:14.640
here's how you check the sources,
link |
00:17:16.440
here's how you form a basic opinion for yourself.
link |
00:17:19.200
And I think that inquisitive nature
link |
00:17:22.880
is paramount to being able to sort through
link |
00:17:26.760
this huge wealth of knowledge.
link |
00:17:29.320
So you need a basic educational foundation
link |
00:17:32.560
based on which you can then add on
link |
00:17:35.520
the sort of domain specific knowledge,
link |
00:17:38.200
but that basic educational foundation
link |
00:17:39.720
should just not just be knowledge,
link |
00:17:42.400
but it should also be epistemology,
link |
00:17:45.240
the way to acquire knowledge.
link |
00:17:47.240
I'm not sure any of us know how to do that
link |
00:17:49.720
in this modern day, we're actually learning.
link |
00:17:51.680
One of the big surprising thing to me
link |
00:17:53.600
about the coronavirus, for example,
link |
00:17:57.280
is that Twitter has been
link |
00:17:59.680
one of the best sources of information.
link |
00:18:02.800
Basically like building your own network of experts,
link |
00:18:07.960
as opposed to the traditional centralized expertise
link |
00:18:11.040
of the WHO and the CDC,
link |
00:18:13.680
or maybe any one particular respectable person
link |
00:18:19.280
at the top of a department in some kind of institution,
link |
00:18:21.760
you instead look at 10, 20, hundreds of people,
link |
00:18:26.520
some of whom are young kids that are incredibly good
link |
00:18:32.600
at aggregating data and plotting and visualizing that data.
link |
00:18:35.800
That's been really surprising to me.
link |
00:18:37.240
I don't know what to make of it.
link |
00:18:39.880
I don't know how that matures into something stable.
link |
00:18:45.480
I don't know if you have ideas.
link |
00:18:47.000
If you were to just try to explain to your kids
link |
00:18:49.960
of where should you go to learn about coronavirus,
link |
00:18:54.960
what would you say?
link |
00:18:56.800
It's such a beautiful example.
link |
00:18:58.080
And I think the current pandemic
link |
00:18:59.920
and the speed at which the scientific community has moved
link |
00:19:03.960
in the current pandemic,
link |
00:19:04.780
I think exemplifies this horizontal transfer
link |
00:19:08.060
and the speed of horizontal transfer of information.
link |
00:19:10.820
The fact that the genome was first sequenced
link |
00:19:15.320
in early January,
link |
00:19:16.380
the first sample was obtained December 29, 2019,
link |
00:19:20.360
a week after the publication of the first genome sequence,
link |
00:19:23.560
Moderna had already finalized its vaccine design
link |
00:19:27.800
and was moving to production.
link |
00:19:29.500
I mean, this is phenomenal.
link |
00:19:31.820
The fact that we go from not knowing
link |
00:19:34.980
what the heck is killing people in Wuhan
link |
00:19:36.740
to wow, it's SARS CoV2 and here's the set of genes,
link |
00:19:41.900
here's the genome, here's the sequence,
link |
00:19:43.580
here are the polymorphisms, et cetera,
link |
00:19:45.660
in the matter of weeks is phenomenal.
link |
00:19:48.220
In that incredible pace of transfer of knowledge,
link |
00:19:52.760
there have been many mistakes.
link |
00:19:54.380
So, some of those mistakes
link |
00:19:56.620
may have been politically motivated
link |
00:19:57.940
or other mistakes may have just been innocuous errors.
link |
00:20:00.860
Others may have been misleading the public
link |
00:20:02.820
for the greater good, such as don't wear masks
link |
00:20:05.540
because we don't want the mask to run out.
link |
00:20:07.220
I mean, that was very silly in my view
link |
00:20:09.060
and a very big mistake.
link |
00:20:11.360
But the spread of knowledge
link |
00:20:15.060
from the scientific community was phenomenal.
link |
00:20:17.300
And some people will point out to bogus articles
link |
00:20:20.680
that snuck in and made the front page.
link |
00:20:22.860
Yeah, they did.
link |
00:20:23.700
But within 24 hours, they were debunked
link |
00:20:26.100
and went out of the front page.
link |
00:20:27.500
And I think that's the beauty of science today.
link |
00:20:30.160
The fact that it's not, oh, knowledge is fixed.
link |
00:20:33.220
It's the ability to embrace that nothing is permanent
link |
00:20:36.980
when it comes to knowledge,
link |
00:20:37.860
that everything is the current best hypothesis
link |
00:20:40.020
and the current best model that best fits the current data
link |
00:20:42.900
and the willingness to be wrong.
link |
00:20:45.780
The expectation that we're gonna be wrong
link |
00:20:48.260
and the celebration of success based on
link |
00:20:50.660
how long was I not proven wrong for,
link |
00:20:52.700
rather than, wow, I was exactly right.
link |
00:20:55.620
Because no one is gonna be exactly right
link |
00:20:57.020
with partial knowledge.
link |
00:20:58.940
But the arc towards perfection,
link |
00:21:03.140
I think is so much more important
link |
00:21:05.280
than how far you are in your first step.
link |
00:21:08.700
And I think that's what sort of
link |
00:21:10.380
the current pandemic has taught us.
link |
00:21:13.420
The fact that, yeah, no, of course,
link |
00:21:14.780
we're gonna make mistakes,
link |
00:21:16.140
but at least we're gonna learn from those mistakes
link |
00:21:18.300
and become better and learn better
link |
00:21:20.340
and spread information better.
link |
00:21:21.340
So if I were to answer the question of,
link |
00:21:23.320
where would you go to learn about coronavirus?
link |
00:21:27.700
First textbook, it all starts with a textbook.
link |
00:21:29.960
Just open up a chapter on virology
link |
00:21:32.580
and how coronaviruses work.
link |
00:21:34.420
Then some basic epidemiology
link |
00:21:36.940
and sort of how pandemics have worked in the past.
link |
00:21:39.860
What are the basic principles surrounding
link |
00:21:41.860
these first wave, second wave?
link |
00:21:43.480
Why do they even exist?
link |
00:21:45.420
Then understanding about growth,
link |
00:21:47.240
understanding about the R0 and RT
link |
00:21:50.260
at various time points.
link |
00:21:52.420
And then understanding the means of spread,
link |
00:21:55.260
how it spreads from person to person.
link |
00:21:57.340
Then how does it get into your cells?
link |
00:22:00.080
From when it gets into the cells,
link |
00:22:01.580
what are the paths that it takes?
link |
00:22:03.260
What are the cell types that express
link |
00:22:05.180
the particular ACE2 receptor?
link |
00:22:07.300
How is your immune system interacting with the virus?
link |
00:22:09.940
And once your immune system launches a defense,
link |
00:22:12.300
how is that helping or actually hurting your health?
link |
00:22:15.520
What about the cytokine storm?
link |
00:22:16.920
What are most people dying from?
link |
00:22:18.560
Why are the comorbidities
link |
00:22:20.020
and these risk factors even applying?
link |
00:22:23.900
What makes obese people respond more
link |
00:22:25.940
or elderly people respond more to the virus
link |
00:22:28.580
while kids are completely,
link |
00:22:32.500
very often not even aware that they're spreading it?
link |
00:22:36.380
So I think there's some basic questions
link |
00:22:41.180
that you would start from.
link |
00:22:42.740
And then I'm sorry to say,
link |
00:22:44.340
but Wikipedia is pretty awesome.
link |
00:22:45.700
Yeah, it is. Google is pretty awesome.
link |
00:22:47.780
It used to be a time,
link |
00:22:48.620
it used to be a time maybe five years ago.
link |
00:22:50.500
I forget when,
link |
00:22:52.000
but people kind of made fun of Wikipedia
link |
00:22:54.260
for being an unreliable source.
link |
00:22:57.260
I never quite understood it.
link |
00:22:58.500
I thought from the early days, it was pretty reliable
link |
00:23:01.260
or better than a lot of the alternatives.
link |
00:23:03.660
But at this point,
link |
00:23:04.780
it's kind of like a solid accessible survey paper
link |
00:23:08.340
on every subject ever.
link |
00:23:10.620
There's an ascertainment bias and a writing bias.
link |
00:23:14.620
So I think this is related to sort of people saying,
link |
00:23:17.820
oh, so many nature papers are wrong.
link |
00:23:20.720
And they're like, why would you publish in nature?
link |
00:23:22.540
So many nature papers are wrong.
link |
00:23:23.680
And my answer is no, no, no.
link |
00:23:26.120
So many nature papers are scrutinized.
link |
00:23:29.440
And just because more of them are being proven wrong
link |
00:23:31.980
than in other articles is actually evidence
link |
00:23:35.380
that they're actually better papers overall
link |
00:23:37.060
because they're being scrutinized at a rate
link |
00:23:39.140
much higher than any other journal.
link |
00:23:41.040
So if you basically judge Wikipedia
link |
00:23:45.560
by not the initial content,
link |
00:23:49.820
but by the number of revisions,
link |
00:23:52.420
then of course it's gonna be the best source
link |
00:23:53.900
of knowledge eventually.
link |
00:23:55.300
It's still very superficial.
link |
00:23:57.120
You then have to go into the review papers,
link |
00:23:58.780
et cetera, et cetera, et cetera.
link |
00:24:00.180
But I mean, for most scientific topics,
link |
00:24:03.380
it's extremely superficial,
link |
00:24:05.060
but it is quite authoritative
link |
00:24:07.660
because it is the place that everybody likes to criticize
link |
00:24:10.780
as being wrong.
link |
00:24:11.660
You say that it's superficial.
link |
00:24:13.620
And a lot of topics that I've studied a lot of,
link |
00:24:18.340
I find it, I don't know if superficial is the right word.
link |
00:24:24.380
Because superficial kind of implies that it's not correct.
link |
00:24:27.700
No, no, no.
link |
00:24:29.100
I don't mean any implication of it not being correct.
link |
00:24:31.660
It's just superficial.
link |
00:24:32.860
It's basically only scratching the surface.
link |
00:24:35.540
For depth, you don't go to Wikipedia.
link |
00:24:37.140
You go to the review articles.
link |
00:24:38.340
But it can be profound in the way that articles rarely,
link |
00:24:41.860
one of the frustrating things to me
link |
00:24:43.300
about certain computer science,
link |
00:24:46.580
like in the machine learning world,
link |
00:24:48.380
articles, they don't as often take the bigger picture view.
link |
00:24:54.900
There's a kind of data set and you show that it works
link |
00:24:57.440
and you kind of show that here's an architecture thing
link |
00:24:59.660
that creates an improvement and so on and so forth.
link |
00:25:02.300
But you don't say, well, what does this mean
link |
00:25:05.300
for the nature of intelligence for future data sets
link |
00:25:08.580
we haven't even thought about?
link |
00:25:10.080
Or if you were trying to implement this,
link |
00:25:11.940
like if we took this data set of 100,000 examples
link |
00:25:15.940
and scale it to 100 billion examples with this method,
link |
00:25:19.260
like look at the bigger picture,
link |
00:25:21.220
which is what a Wikipedia article would actually try to do,
link |
00:25:25.540
which is like, what does this mean in the context
link |
00:25:28.540
of the broad field of computer vision or something like that?
link |
00:25:32.380
Yeah, no, I agree with you completely, but it depends
link |
00:25:35.340
on the topic.
link |
00:25:36.180
I mean, for some topics, there's been a huge amount of work.
link |
00:25:38.420
For other topics, it's just a stub.
link |
00:25:40.300
So, you know.
link |
00:25:41.580
I got it.
link |
00:25:42.420
Yeah.
link |
00:25:43.240
Well, yeah, actually the, which we'll talk on,
link |
00:25:46.380
genomics was not great.
link |
00:25:48.060
Yeah, it's very shallow, yeah, yeah.
link |
00:25:50.460
It's not wrong, it's just shallow.
link |
00:25:51.860
It's shallow.
link |
00:25:52.700
Yeah, every time I criticize something,
link |
00:25:54.700
I should feel partly responsible.
link |
00:25:56.320
Basically, if more people from my community went there
link |
00:25:58.740
and edited, it would not be shallow.
link |
00:26:01.120
It's just that there's different modes of communication
link |
00:26:04.020
in different fields.
link |
00:26:05.280
And in some fields, the experts have embraced Wikipedia.
link |
00:26:08.980
In other fields, it's relegated.
link |
00:26:11.180
And perhaps the reason is that if it was any better
link |
00:26:15.860
to start with, people would invest more time.
link |
00:26:18.000
But if it's not great to start with,
link |
00:26:19.980
then you need a few initial pioneers who will basically
link |
00:26:22.860
go in and say, ah, enough, we're just gonna fix that.
link |
00:26:26.460
And then I think it'll catch on much more.
link |
00:26:29.120
So if it's okay, before we go on to genomics,
link |
00:26:32.220
can we linger a little bit longer on the beauty
link |
00:26:35.420
of the human genome?
link |
00:26:37.140
You've given me a few notes.
link |
00:26:38.580
What else do you find beautiful about the human genome?
link |
00:26:41.660
So the last aspect of what makes the human genome unique,
link |
00:26:44.860
in addition to the, you know, similarity and the differences
link |
00:26:49.980
and the individuality is that, so very early on,
link |
00:26:56.340
people would basically say, oh, you don't do that
link |
00:26:58.020
experiment in human, you have to learn about that in fly,
link |
00:27:01.260
or you have to learn about that in yeast first,
link |
00:27:03.140
or in mouse first, or in a primate first.
link |
00:27:05.900
And the human genome was in fact relegated to sort of,
link |
00:27:09.040
oh, the last place that you're gonna go
link |
00:27:11.020
to learn something new.
link |
00:27:12.640
That has dramatically changed.
link |
00:27:14.220
And the reason that changed is human genetics.
link |
00:27:18.620
We are the species in the planet
link |
00:27:22.500
that's the most studied right now.
link |
00:27:24.660
It's embarrassing to say that,
link |
00:27:26.260
but this was not the case a few years ago.
link |
00:27:28.380
It used to be, you know, first viruses, then bacteria,
link |
00:27:33.840
then yeast, then the fruit fly and the worm,
link |
00:27:37.880
then the mouse, and eventually human was very far last.
link |
00:27:42.420
So it's embarrassing that it took us this long
link |
00:27:44.740
to focus on it, or the...
link |
00:27:46.580
It's embarrassing that the model organisms
link |
00:27:49.220
have been taken over because of the power of human genetics.
link |
00:27:52.660
That right now, it's actually simpler to figure out
link |
00:27:55.420
the phenotype of something by mining
link |
00:27:58.820
this massive amount of human data
link |
00:28:01.380
than by going back to any of the other species.
link |
00:28:04.020
And the reason for that is that if you look
link |
00:28:05.540
at the natural variation that happens
link |
00:28:07.360
in a population of seven billion,
link |
00:28:09.700
you basically have a mutation in almost every nucleotide.
link |
00:28:13.380
So every nucleotide you wanna perturb,
link |
00:28:15.680
you can go find a living, breathing human being
link |
00:28:18.780
and go test the function of that nucleotide
link |
00:28:20.360
by sort of searching the database and finding that person.
link |
00:28:22.620
Wait, why is that embarrassing?
link |
00:28:23.660
It's a beautiful data set.
link |
00:28:24.700
It's a beautiful data set.
link |
00:28:26.380
It's embarrassing for the model organism.
link |
00:28:29.300
For the flies.
link |
00:28:30.140
Yeah, exactly.
link |
00:28:30.980
I mean, do you feel on a small tangent,
link |
00:28:34.940
is there something of value in the genome of a fly
link |
00:28:40.060
and other of these model organisms that you miss
link |
00:28:43.740
that we wish we would be looking at deeper?
link |
00:28:47.420
So directed perturbation, of course.
link |
00:28:49.900
So I think the place where humans are still lagging
link |
00:28:54.140
is the fact that in an animal model,
link |
00:28:55.700
you can go and say,
link |
00:28:56.540
well, let me knock out this gene completely
link |
00:28:58.620
and let me knock out these three genes completely.
link |
00:29:00.580
And the moment you get into combinatorics,
link |
00:29:02.780
it's something you can't do in the human
link |
00:29:04.180
because there just simply aren't enough humans
link |
00:29:05.980
on the planet.
link |
00:29:07.060
And again, let me be honest,
link |
00:29:08.820
we haven't sequenced all seven billion people.
link |
00:29:11.180
It's not like we have every mutation,
link |
00:29:12.820
but we know that there's a carrier out there.
link |
00:29:15.060
So if you look at the trend and the speed
link |
00:29:17.500
with which human genetics has progressed,
link |
00:29:19.460
we can now find thousands of genes involved
link |
00:29:23.300
in human cognition, in human psychology,
link |
00:29:27.060
in the emotions and the feelings
link |
00:29:29.100
that we used to think are uniquely learned.
link |
00:29:31.780
It turns out there's a genetic basis to a lot of that.
link |
00:29:34.380
So the human genome has continued to elucidate
link |
00:29:42.540
through these studies of genetic variation,
link |
00:29:44.860
so many different processes that we previously thought
link |
00:29:47.500
were something like free will.
link |
00:29:52.300
Free will is this beautiful concept
link |
00:29:54.260
that humans have had for a long time.
link |
00:29:58.060
In the end, it's just a bunch of chemical reactions
link |
00:29:59.860
happening in your brain.
link |
00:30:00.740
And the particular abundance of receptors
link |
00:30:03.140
that you have this day based on what you ate yesterday
link |
00:30:06.100
or that you have been wired with based on your parents
link |
00:30:10.380
and your upbringing, et cetera,
link |
00:30:12.580
determines a lot of that quote unquote free will component
link |
00:30:15.700
to sort of narrow and narrow sort of slices.
link |
00:30:20.700
So how much on that point, how much freedom
link |
00:30:24.140
do you think we have to escape the constraints
link |
00:30:29.020
of our genome?
link |
00:30:30.420
You're making it sound like more and more
link |
00:30:31.980
we're discovering that our genome is actually has the,
link |
00:30:35.060
a lot of the story already encoded into it.
link |
00:30:37.740
How much freedom do we have?
link |
00:30:39.580
I, so let me describe what that freedom would look like.
link |
00:30:45.140
That freedom would be my saying,
link |
00:30:47.620
ooh, I'm gonna resist the urge to eat that apple
link |
00:30:51.540
because I choose not to.
link |
00:30:54.500
But there are chemical receptors that made me
link |
00:30:57.620
not resist the urge to prove my individuality
link |
00:31:01.340
and my free will by resisting the apple.
link |
00:31:04.100
So then the next question is,
link |
00:31:05.580
well, maybe now I'll resist the urge to resist the apple
link |
00:31:08.220
and I'll go for the chocolate instead
link |
00:31:09.540
to prove my individuality.
link |
00:31:10.780
But then what about those other receptors that, you know?
link |
00:31:14.460
That might be all encoded in there.
link |
00:31:17.780
So it's kicking the bucket down the road
link |
00:31:19.460
and basically saying, well, your choice
link |
00:31:22.020
will may have actually been driven by other things
link |
00:31:24.900
that you actually are not choosing.
link |
00:31:27.860
So that's why it's very hard to answer that question.
link |
00:31:30.020
It's hard to know what to do with that.
link |
00:31:31.420
I mean, if the genome has,
link |
00:31:35.820
if there's not much freedom, it's a...
link |
00:31:38.500
It's the butterfly effect.
link |
00:31:40.500
It's basically that in the short term,
link |
00:31:42.900
you can predict something extremely well
link |
00:31:45.700
by knowing the current state of the system.
link |
00:31:48.100
But a few steps down, it's very hard to predict
link |
00:31:50.700
based on the current knowledge.
link |
00:31:52.380
Is that because the system is truly free?
link |
00:31:55.220
When I look at weather patterns,
link |
00:31:56.340
I can predict the next 10 days.
link |
00:31:57.860
Is it because the weather has a lot of freedom
link |
00:32:00.260
and after 10 days it chooses to do something else?
link |
00:32:03.420
Or is it because in fact the system is fully deterministic
link |
00:32:07.300
and there's just a slightly different magnetic field
link |
00:32:10.100
of the earth, slightly more energy arriving from the sun,
link |
00:32:12.420
a slightly different spin of the gravitational pull
link |
00:32:15.140
of Jupiter that is now causing all kinds of tides
link |
00:32:18.860
and slight deviation of the moon, et cetera.
link |
00:32:20.860
Maybe all of that can be fully modeled.
link |
00:32:22.940
Maybe the fact that China is emitting
link |
00:32:25.740
a little more carbon today is actually gonna affect
link |
00:32:28.180
the weather in Egypt in three weeks.
link |
00:32:31.460
And all of that could be fully modeled.
link |
00:32:33.860
In the same way, if you take a complete view
link |
00:32:36.780
of a human being now, I model everything about you.
link |
00:32:42.700
The question is, can I predict your next step?
link |
00:32:44.860
Probably, but at how far?
link |
00:32:47.740
And if it's a little further, is that because of stochasticity
link |
00:32:51.260
and sort of chaos properties of unpredictability
link |
00:32:54.580
of beyond a certain level?
link |
00:32:56.100
Or was that actually true free will?
link |
00:32:58.260
Yeah, so the number of variables might be so,
link |
00:33:01.260
you might need to build an entire universe to be able to model.
link |
00:33:05.260
To simulate a human, and then maybe that human
link |
00:33:07.740
will be fully simulatable.
link |
00:33:09.420
But maybe aspects of free will will exist.
link |
00:33:12.220
And where's that free will coming from?
link |
00:33:13.380
It's still coming from the same neurons
link |
00:33:14.980
or maybe from a spirit inhabiting these neurons.
link |
00:33:17.580
But again, it's very difficult empirically
link |
00:33:19.740
to sort of evaluate where does free will begin
link |
00:33:22.540
and sort of chemical reactions and electric signals.
link |
00:33:26.700
So on that topic, let me ask the most absurd question
link |
00:33:31.140
that most MIT faculty rolled their eyes on.
link |
00:33:33.900
But what do you think about the simulation hypothesis
link |
00:33:38.260
and the idea that we live in a simulation?
link |
00:33:40.220
I think it's complete BS.
link |
00:33:41.580
Okay.
link |
00:33:44.540
There's no empirical evidence.
link |
00:33:45.740
No, it's not. Absolutely not.
link |
00:33:47.060
Not in terms of empirical evidence or not,
link |
00:33:49.020
but in terms of a thought experiment,
link |
00:33:52.380
does it help you think about the universe?
link |
00:33:54.860
I mean, so if you look at the genome,
link |
00:33:57.500
it's encoding a lot of the information
link |
00:33:59.180
that is required to create some of the beautiful
link |
00:34:01.500
human complexity that we see around us.
link |
00:34:04.220
It's an interesting thought experiment.
link |
00:34:05.940
How much parameters do we need to have
link |
00:34:11.340
in order to model this full human experience?
link |
00:34:15.300
Like if we were to build a video game,
link |
00:34:17.540
how hard it would be to build a video game
link |
00:34:19.980
that's like convincing enough and fun enough
link |
00:34:22.660
and it has consistent laws of physics, all that stuff.
link |
00:34:28.340
It's not interesting to use a thought experiment.
link |
00:34:31.380
I mean, it's cute, but it's Occam's razor.
link |
00:34:35.060
I mean, what's more realistic,
link |
00:34:36.820
the fact that you're actually a machine
link |
00:34:38.340
or that you're a person?
link |
00:34:39.740
What's the fact that all of my experiences exist
link |
00:34:43.340
inside the chemical molecules that I have
link |
00:34:45.540
or that somebody is actually simulating all that?
link |
00:34:49.540
Well, you did refer to humans
link |
00:34:50.860
as a digital computer earlier.
link |
00:34:52.540
Of course, of course.
link |
00:34:53.420
But that does not.
link |
00:34:54.260
It's a kind of a machine, right?
link |
00:34:55.300
I know, I know.
link |
00:34:56.380
But I think the probability of all that is nil
link |
00:35:01.740
and let the machines wake me up
link |
00:35:03.500
and just terminate me now if it's not.
link |
00:35:07.540
I challenge you machines.
link |
00:35:08.860
They're gonna wait a little bit
link |
00:35:10.940
to see what you're gonna do next.
link |
00:35:12.380
It's fun.
link |
00:35:13.220
It's fun to watch, especially the clever humans.
link |
00:35:17.380
What's the difference to you
link |
00:35:18.540
between the way a computer stores information
link |
00:35:21.300
and the human genome stores information?
link |
00:35:24.020
So you also have roots and your work.
link |
00:35:27.020
Would you say when you introduce yourself at a bar.
link |
00:35:31.980
It depends who I'm talking to.
link |
00:35:34.020
Would you say it's computational biology?
link |
00:35:36.180
Do you reveal your expertise in computers?
link |
00:35:43.300
It depends who I'm talking to, truly.
link |
00:35:45.340
I mean, basically, if I meet someone who's in computers,
link |
00:35:47.700
I'll say, oh, I'm a professor in computer science.
link |
00:35:51.100
If I meet someone who's in engineering,
link |
00:35:52.500
I say computer science and electrical engineering.
link |
00:35:54.780
If I meet someone in biology,
link |
00:35:55.980
I'll say, hey, I work in genomics.
link |
00:35:57.220
If I meet someone in medicine,
link |
00:35:58.300
I'm like, hey, I work on genetics.
link |
00:36:00.740
So you're a fun person to meet at a bar.
link |
00:36:02.220
I got you, but so.
link |
00:36:03.940
No, no, but what I'm trying to say is that I don't,
link |
00:36:07.460
I mean, there's no single attribute
link |
00:36:09.100
that I will define myself as.
link |
00:36:11.140
There's a few things I know.
link |
00:36:12.140
There's a few things I study.
link |
00:36:13.140
There's a few things I have degrees on
link |
00:36:15.100
and there's a few things that I grant degrees in.
link |
00:36:17.980
And I publish papers across the whole gamut,
link |
00:36:22.900
the whole spectrum of computation to biology, et cetera.
link |
00:36:26.380
I mean, the complete answer is that I use computer science
link |
00:36:31.580
to understand biology.
link |
00:36:34.180
So I develop methods in AI and machine learning,
link |
00:36:39.460
statistics and algorithms, et cetera.
link |
00:36:41.700
But the ultimate goal of my career
link |
00:36:44.060
is to really understand biology.
link |
00:36:45.700
If these things don't advance our understanding
link |
00:36:47.780
of biology, I'm not as fascinated by them.
link |
00:36:51.980
Although there are some beautiful computational problems
link |
00:36:54.940
by themselves, I've sort of made it my mission
link |
00:36:57.940
to apply the power of computer science
link |
00:37:01.660
to truly understand the human genome, health, disease,
link |
00:37:07.500
and the whole gamut of how our brain works,
link |
00:37:10.100
how our body works and all of that,
link |
00:37:11.740
which is so fascinating.
link |
00:37:13.980
And so the dream, there's not an equivalent
link |
00:37:16.940
sort of complimentary dream of understanding
link |
00:37:20.940
human biology in order to create an artificial life
link |
00:37:23.340
or an artificial brain or artificial intelligence
link |
00:37:26.060
that supersedes the intelligence
link |
00:37:27.660
and the capabilities of us humans.
link |
00:37:30.740
It's an interesting question.
link |
00:37:31.860
It's a fascinating question.
link |
00:37:33.260
So understanding the human brain is undoubtedly coupled
link |
00:37:39.740
to how do we make better AI?
link |
00:37:42.180
Because so much of AI has in fact been inspired
link |
00:37:46.420
by the brain.
link |
00:37:47.260
It may have taken 50 years
link |
00:37:49.060
since the early days of neural networks
link |
00:37:51.140
till we have all of these amazing progress
link |
00:37:55.420
that we've seen with deep belief networks
link |
00:38:00.820
and all of these advances in Go, in Chess,
link |
00:38:06.460
in image synthesis, in deep fakes, in you name it.
link |
00:38:10.420
But the underlying architecture is very much inspired
link |
00:38:17.020
by the human brain,
link |
00:38:18.060
which actually posits a very, very interesting question.
link |
00:38:22.580
Why are neural networks performing so well?
link |
00:38:27.220
And they perform amazingly well.
link |
00:38:28.980
Is it because they can simulate any possible function?
link |
00:38:32.580
And the answer is no, no.
link |
00:38:34.420
They simulate a very small number of functions.
link |
00:38:37.180
Is it because they can simulate every function
link |
00:38:39.420
in the universe?
link |
00:38:40.500
And that's where it gets interesting.
link |
00:38:41.540
The answer is actually, yeah, a little closer to that.
link |
00:38:44.740
And here's where it gets really fun.
link |
00:38:47.700
If you look at human brain and human cognition,
link |
00:38:51.700
it didn't evolve in a vacuum.
link |
00:38:53.980
It evolved in a world with physical constraints,
link |
00:38:58.780
like the world that inhabits us.
link |
00:39:00.700
It is the world that we inhabit.
link |
00:39:03.220
And if you look at our senses, what do they perceive?
link |
00:39:08.220
They perceive different parts of the electromagnetic spectrum.
link |
00:39:13.220
The hearing is just different movements in air,
link |
00:39:17.260
the touch, et cetera.
link |
00:39:18.820
I mean, all of these things,
link |
00:39:20.100
we've built intuitions for the physical world
link |
00:39:22.700
that we inhabit.
link |
00:39:23.980
And our brains and the brains of all animals evolved
link |
00:39:27.660
for that world.
link |
00:39:29.140
And the AI systems that we have built
link |
00:39:32.660
happen to work well with images
link |
00:39:34.700
of the type that we encounter
link |
00:39:36.100
in the physical world that we inhabit.
link |
00:39:38.380
Whereas if you just take noise and you add random signal
link |
00:39:42.420
that doesn't match anything in our world,
link |
00:39:44.420
neural networks will not do as well.
link |
00:39:46.940
And that actually basically has this whole loop around this,
link |
00:39:52.900
which is this was designed by studying our own brain,
link |
00:39:57.620
which was evolved for our own world.
link |
00:39:59.580
And they happen to do well in our own world.
link |
00:40:01.940
And they happen to make the same types of mistakes
link |
00:40:04.140
that humans make many times.
link |
00:40:07.020
And of course you can engineer images
link |
00:40:08.740
by adding just the right amount of sort of pixel deviations
link |
00:40:12.580
to make a zebra look like a bamboo and stuff like that,
link |
00:40:15.780
or like a table.
link |
00:40:18.380
But ultimately the undoctored images at least
link |
00:40:23.580
are very often mistaken, I don't know,
link |
00:40:25.940
between muffins and dogs, for example,
link |
00:40:28.860
in the same way that humans make those mistakes.
link |
00:40:31.220
So there's no doubt in my view
link |
00:40:35.820
that the more we understand about the tricks
link |
00:40:38.580
that our human brain has evolved
link |
00:40:40.580
to understand the physical world around us,
link |
00:40:42.900
the more we will be able to bring
link |
00:40:44.740
new computational primitives in our AI systems
link |
00:40:48.780
to again better understand not just the world around us,
link |
00:40:52.220
but maybe even the world inside us,
link |
00:40:54.460
and maybe even the computational problems that arise
link |
00:40:57.180
from new types of data that we haven't been exposed to,
link |
00:41:00.380
but are yet inhabiting the same universe that we live in
link |
00:41:03.460
with a very tiny little subset of functions
link |
00:41:06.100
from all possible mathematical functions.
link |
00:41:08.140
Yeah, and that small subset of functions,
link |
00:41:10.220
all that matters to us humans really, that's what makes.
link |
00:41:12.940
It's all that has mattered so far.
link |
00:41:14.860
And even within our scientific realm,
link |
00:41:17.100
it's all that seems to continue to matter.
link |
00:41:19.740
But I mean, I always like to think about our senses
link |
00:41:24.860
and how much of the physical world around us we perceive.
link |
00:41:29.380
And if you look at the LIGO experiment
link |
00:41:35.020
over the last year and a half has been all over the news.
link |
00:41:38.220
What did LIGO do?
link |
00:41:39.660
It created a new sense for human beings,
link |
00:41:42.940
a sense that has never been sensed
link |
00:41:45.820
in the history of our planet.
link |
00:41:48.980
Gravitational waves have been traversing the earth
link |
00:41:53.020
since its creation a few billion years ago.
link |
00:41:55.220
Life has evolved senses to sense things
link |
00:41:59.580
that were never before sensed.
link |
00:42:02.220
Light was not perceived by early life.
link |
00:42:05.780
No one cared.
link |
00:42:07.580
And eventually photoreceptors evolved
link |
00:42:11.260
and the ability to sense colors
link |
00:42:14.220
by sort of catching different parts
link |
00:42:16.060
of that electromagnetic spectrum.
link |
00:42:19.140
And hearing evolved and touch evolved, et cetera.
link |
00:42:23.380
But no organism evolved a way to sense neutrinos
link |
00:42:27.700
floating through earth or gravitational waves
link |
00:42:29.940
flowing through earth, et cetera.
link |
00:42:31.260
And I find it so beautiful in the history
link |
00:42:33.860
of not just humanity, but life on the planet
link |
00:42:37.020
that we are now able to capture additional signals
link |
00:42:40.460
from the physical world than we ever knew before.
link |
00:42:43.620
And axions, for example, have been all over the news
link |
00:42:46.340
in the last few weeks.
link |
00:42:47.460
And the concept that we can capture and perceive
link |
00:42:53.580
more of that physical world is as exciting
link |
00:42:57.660
as the fact that we were blind to it
link |
00:43:01.980
is traumatizing before.
link |
00:43:04.620
Because that also tells us, you know, we're in 2020.
link |
00:43:09.380
Picture yourself in 3020 or in 20, you know.
link |
00:43:12.820
What new senses might we discover?
link |
00:43:15.580
Is it, you know, could it be that we're missing
link |
00:43:19.580
nine tenths of physics?
link |
00:43:21.900
That like, there's a lot of physics out there
link |
00:43:23.980
that we're just blind to, completely oblivious to it.
link |
00:43:27.900
And yet they're permeating us all the time.
link |
00:43:29.340
Yeah, so it might be right in front of us.
link |
00:43:31.140
So when you're thinking about premonitions,
link |
00:43:35.060
yeah, a lot of that is ascertainment bias.
link |
00:43:37.580
Like, yeah, you know, every now and then you're like,
link |
00:43:39.420
oh, I remember my friend.
link |
00:43:41.020
And then my friend doesn't appear
link |
00:43:42.660
and I'll forget that I remembered my friend.
link |
00:43:44.540
But every now and then my friend will actually appear.
link |
00:43:45.980
I'm like, oh my God, I thought about you a minute ago.
link |
00:43:48.340
You just called me, that's amazing.
link |
00:43:50.140
So, you know, some of that is this,
link |
00:43:51.980
but some of that might be that there are,
link |
00:43:55.060
within our brain, sensors for waves
link |
00:43:59.900
that we emit that we're not even aware of.
link |
00:44:03.220
And this whole concept of when I hug my children,
link |
00:44:07.020
there's such an emotional transfer there
link |
00:44:10.460
that we don't comprehend.
link |
00:44:12.220
I mean, sure, yeah, of course we're all like hard wire
link |
00:44:15.100
for all kinds of touchy feely things
link |
00:44:16.700
between parents and kids, it's beautiful,
link |
00:44:18.220
between partners, it's beautiful, et cetera.
link |
00:44:20.660
But then there are intangible aspects
link |
00:44:24.900
of human communication
link |
00:44:27.340
that I don't think it's unfathomable
link |
00:44:30.020
that our brain has actually evolved waves and sensors
link |
00:44:32.060
for it that we just don't capture.
link |
00:44:33.940
We don't understand the function
link |
00:44:35.220
of the vast majority of our neurons.
link |
00:44:37.420
And maybe our brain is already sensing it,
link |
00:44:40.100
but even worse, maybe our brain is not sensing it at all.
link |
00:44:43.940
And we're oblivious to this until we build a machine
link |
00:44:46.620
that suddenly is able to sort of capture
link |
00:44:48.300
so much more of what's happening in the natural world.
link |
00:44:50.340
So what you're saying is physics
link |
00:44:52.620
is going to discover a sensor for love.
link |
00:44:57.220
And maybe dogs are off scale for that.
link |
00:45:01.460
And we've been oblivious to it the whole time
link |
00:45:04.140
because we didn't have the right sensor.
link |
00:45:05.740
And now you're gonna have a little wrist that says,
link |
00:45:07.420
oh my God, I feel all this love in the house.
link |
00:45:09.660
I sense a disturbance in the forest.
link |
00:45:11.860
It's all around us.
link |
00:45:13.660
And dogs and cats will have zero.
link |
00:45:15.780
None. None.
link |
00:45:17.020
It's just.
link |
00:45:17.860
Oh, no signal.
link |
00:45:20.100
But let's take a step back to our unfortunate place.
link |
00:45:24.540
To one of the 400 topics that we had actually planned for.
link |
00:45:29.580
But to our sad time in 2020
link |
00:45:31.820
when we only have just a few sensors
link |
00:45:33.860
and very primitive early computers.
link |
00:45:37.620
So you have a foot in computer science
link |
00:45:41.820
and a foot in biology.
link |
00:45:43.500
In your sense, how do computers represent information
link |
00:45:48.300
differently than like the genome or biological systems?
link |
00:45:52.300
So first of all, let me correct
link |
00:45:55.540
that no, we're in an amazing time in 2020.
link |
00:46:00.340
Computer science is totally awesome.
link |
00:46:02.460
And physics is totally awesome.
link |
00:46:03.980
And we have understood so much of the natural world
link |
00:46:06.900
than ever before.
link |
00:46:08.500
So I am extremely grateful and feeling extremely lucky
link |
00:46:13.140
to be living in the time that we are.
link |
00:46:16.180
Cause you know, first of all,
link |
00:46:17.540
who knows when the asteroid will hit.
link |
00:46:20.140
And second, you know, of all times in humanity,
link |
00:46:26.140
this is probably the best time to be a human being.
link |
00:46:29.380
And this might actually be the best place
link |
00:46:31.100
to be a human being.
link |
00:46:31.940
So anyway, you know, for anyone who loves science,
link |
00:46:34.420
this is it.
link |
00:46:35.260
This is awesome.
link |
00:46:36.100
This is a great time.
link |
00:46:36.940
At the same time, just a quick comment.
link |
00:46:39.300
All I meant is that if we look several hundred years
link |
00:46:43.060
from now and we end up somehow not destroying ourselves,
link |
00:46:48.500
people will probably look back at this time
link |
00:46:50.300
in computer science and at your work of Manos at MIT.
link |
00:46:55.620
As infantile.
link |
00:46:56.580
As infantile and silly and how ignorant it all was.
link |
00:46:59.620
I like to joke very often with my students
link |
00:47:02.500
that, you know, we've written so many papers.
link |
00:47:04.220
We've published so much.
link |
00:47:05.260
We've been citing so much.
link |
00:47:06.460
And every single time I tell my students, you know,
link |
00:47:08.380
the best is ahead of us.
link |
00:47:09.700
What we're working on now
link |
00:47:11.380
is the most exciting thing I've ever worked on.
link |
00:47:13.860
So in a way, I do have this sense of, yeah,
link |
00:47:16.420
even the papers I wrote 10 years ago,
link |
00:47:18.540
they were awesome at the time,
link |
00:47:20.300
but I'm so much more excited about where we're heading now.
link |
00:47:22.380
And I don't mean to minimize any of the stuff
link |
00:47:24.500
we've done in the past,
link |
00:47:25.460
but you know, there's just this sense of excitement
link |
00:47:29.020
about what you're working on now
link |
00:47:30.980
that as soon as a paper is submitted,
link |
00:47:33.380
it's like, ugh, it's old.
link |
00:47:35.540
You know, I can't talk about that anymore.
link |
00:47:37.140
I'm not gonna talk about it.
link |
00:47:37.980
At the same time, you're not,
link |
00:47:38.820
you probably are not going to be able to predict
link |
00:47:41.340
what are the most impactful papers and ideas
link |
00:47:45.500
when people look back 200 years from now at your work,
link |
00:47:47.860
what would be the most exciting papers.
link |
00:47:50.740
And it may very well be not the thing that you expected.
link |
00:47:54.220
Or the things you got awards for or, you know.
link |
00:47:58.100
This might be true in some fields.
link |
00:47:59.980
I don't know.
link |
00:48:00.820
I feel slightly differently about it in our field.
link |
00:48:02.340
I feel that I kind of know what are the important ones.
link |
00:48:05.660
And there's a very big difference
link |
00:48:07.300
between what the press picks up on
link |
00:48:09.180
and what's actually fundamentally important for the field.
link |
00:48:11.620
And I think for the fundamentally important ones,
link |
00:48:13.380
we kind of have a pretty good idea what they are.
link |
00:48:15.580
And it's hard to sometimes get the press excited
link |
00:48:18.140
about the fundamental advances,
link |
00:48:20.100
but you know, we take what we get
link |
00:48:23.700
and celebrate what we get.
link |
00:48:24.740
And sometimes, you know, one of our papers,
link |
00:48:27.180
which was in a minor journal,
link |
00:48:28.500
made the front page of Reddit
link |
00:48:30.180
and suddenly had like hundreds of thousands of views.
link |
00:48:33.500
Even though it was in a minor journal
link |
00:48:34.980
because, you know, somebody pitched it the right way
link |
00:48:37.020
that it suddenly caught everybody's attention.
link |
00:48:39.380
Whereas other papers that are sort of truly fundamental,
link |
00:48:42.020
you know, we have a hard time
link |
00:48:43.660
getting the editors even excited about them
link |
00:48:46.060
when so many hundreds of people
link |
00:48:47.860
are already using the results and building upon them.
link |
00:48:50.860
So I do appreciate that there's a discrepancy
link |
00:48:54.420
between the perception and the perceived success
link |
00:48:57.420
and the awards that you get for various papers.
link |
00:48:59.500
But I think that fundamentally, I know that, you know,
link |
00:49:02.500
some paper, I'm so, so when you write.
link |
00:49:04.380
So is there a paper that you're most proud of?
link |
00:49:06.820
See, now you just, you trapped yourself.
link |
00:49:09.340
No, no, no, no, I mean.
link |
00:49:10.340
Is there a line of work that you have a sense
link |
00:49:14.620
is really powerful that you've done to date?
link |
00:49:17.580
You've done so much work in so many directions,
link |
00:49:20.180
which is interesting.
link |
00:49:21.860
Is there something where you think is quite special?
link |
00:49:25.340
I mean, it's like asking me to say
link |
00:49:28.740
which of my three children I love best.
link |
00:49:30.380
I mean.
link |
00:49:34.060
Exactly.
link |
00:49:34.900
So, I mean, and it's such a gimme question
link |
00:49:38.500
that is so, so difficult not to brag
link |
00:49:42.580
about the awesome work that my team
link |
00:49:44.740
and my students have done.
link |
00:49:47.060
And I'll just mention a few off the top of my head.
link |
00:49:49.940
I mean, basically there's a few landmark papers
link |
00:49:53.060
that I think have shaped my scientific path.
link |
00:49:56.780
And, you know, I like to somehow describe it
link |
00:50:00.380
as a linear continuation of one thing led to another
link |
00:50:03.620
and led to another led to another.
link |
00:50:05.340
And, you know, it kind of all started with,
link |
00:50:11.020
skip, skip, skip, skip, skip.
link |
00:50:12.340
Let me try to start somewhere in the middle.
link |
00:50:14.020
So my first PhD paper was the first comparative analysis
link |
00:50:20.460
of multiple species.
link |
00:50:21.820
So multiple complete genomes.
link |
00:50:23.580
So for the first time we basically developed the concept
link |
00:50:27.340
of genome wide evolutionary signatures.
link |
00:50:29.980
The fact that you could look across the entire genome
link |
00:50:32.940
and understand how things evolve.
link |
00:50:35.660
And from these signatures of evolution
link |
00:50:38.260
you could go back and study any one region
link |
00:50:41.540
and say, that's a protein coding gene.
link |
00:50:44.020
That's an RNA gene.
link |
00:50:45.540
That's a regulatory motif.
link |
00:50:47.260
That's a, you know, binding site and so on and so forth.
link |
00:50:50.100
So.
link |
00:50:50.940
I'm sorry, so comparing different.
link |
00:50:52.660
Different species.
link |
00:50:53.780
Species of the same.
link |
00:50:55.060
So take human, mouse, rat and dog.
link |
00:50:57.140
Yeah.
link |
00:50:58.060
You know, they're all animals, they're all mammals.
link |
00:50:59.980
They're all performing similar functions with their heart,
link |
00:51:02.820
with their brain, with their lungs, et cetera, et cetera.
link |
00:51:05.860
So there's many functional elements
link |
00:51:08.140
that make us uniquely mammalian.
link |
00:51:10.900
And those mammalian elements are actually conserved.
link |
00:51:14.620
99% of our genome does not code for protein.
link |
00:51:18.940
1% codes for protein.
link |
00:51:20.780
The other 99%, we frankly didn't know what it does
link |
00:51:25.100
until we started doing this comparative genomic studies.
link |
00:51:28.140
So basically these series of papers in my career
link |
00:51:32.060
have basically first developed that concept
link |
00:51:34.540
of evolutionary signatures and then apply them to yeast,
link |
00:51:37.460
apply them to flies, apply them to four mammals,
link |
00:51:40.140
apply them to 17 fungi,
link |
00:51:41.620
apply them to 12 Drosophila species,
link |
00:51:43.700
apply them to then 29 mammals and now 200 mammals.
link |
00:51:46.900
So sorry, so can we.
link |
00:51:48.820
So the evolutionary signatures seems like
link |
00:51:51.380
it's such a fascinating idea.
link |
00:51:53.580
And we're probably gonna linger on your early PhD work
link |
00:51:57.380
for two hours.
link |
00:51:58.220
But what is, how can you reveal something interesting
link |
00:52:04.260
about the genome by looking at the multiple,
link |
00:52:08.500
multiple species and looking at the evolutionary signatures?
link |
00:52:11.900
Yeah, so you basically align
link |
00:52:16.900
the matching regions.
link |
00:52:20.820
So everything evolved from a common ancestor way, way back.
link |
00:52:23.980
And mammals evolved from a common ancestor
link |
00:52:26.020
about 60 million years back.
link |
00:52:27.860
So after the meteor that killed off the dinosaurs landed
link |
00:52:35.460
near Machu Picchu, we know the crater.
link |
00:52:38.780
It didn't allegedly land.
link |
00:52:41.700
That was the aliens, okay.
link |
00:52:42.860
No, just slightly north of Machu Picchu
link |
00:52:44.660
in the Gulf of Mexico, there's a giant hole
link |
00:52:47.100
that that meteor impact.
link |
00:52:49.060
Sorry, is that definitive to people?
link |
00:52:51.380
Have people conclusively figured out
link |
00:52:56.380
what killed the dinosaurs?
link |
00:52:58.180
I think so.
link |
00:52:59.220
So it was a meteor?
link |
00:53:00.540
Well, volcanic activity, all kinds of other stuff
link |
00:53:04.860
is coinciding, but the meteor is pretty unique
link |
00:53:09.580
and we now have. That's also terrifying.
link |
00:53:11.180
I wouldn't, we still have a lot of 2020 left,
link |
00:53:14.940
so if anything.
link |
00:53:15.780
No, no, but think about it this way.
link |
00:53:17.220
So the dinosaurs ruled the earth for 175 million years.
link |
00:53:24.420
We humans have been around for what?
link |
00:53:28.380
Less than 1 million years.
link |
00:53:29.940
If you're super generous about what you call humans
link |
00:53:32.900
and you include chimps basically.
link |
00:53:35.340
So we are just getting warmed up
link |
00:53:38.580
and we've ruled the planet much more ruthlessly
link |
00:53:42.500
than Tyrannosaurus Rex.
link |
00:53:46.220
T Rex had much less of an environmental impact
link |
00:53:48.340
than we did.
link |
00:53:49.580
And if you give us another 174 million years,
link |
00:53:54.020
humans will look very different if we make it that far.
link |
00:53:58.380
So I think dinosaurs basically are much more
link |
00:54:02.180
of life history on earth than we are in all respects.
link |
00:54:06.100
But look at the bright side, when they were killed off,
link |
00:54:08.740
another life form emerged, mammals.
link |
00:54:10.860
And that's that whole evolutionary branching
link |
00:54:14.620
that's happened.
link |
00:54:15.460
So you kind of have,
link |
00:54:17.060
when you have these evolutionary signatures,
link |
00:54:19.180
is there basically a map of how the genome changed?
link |
00:54:22.660
Yeah, exactly, exactly.
link |
00:54:23.540
So now you can go back to this early mammal
link |
00:54:26.180
that was hiding in caves and you can basically ask
link |
00:54:29.260
what happened after the dinosaurs were wiped out.
link |
00:54:31.300
A ton of evolutionary niches opened up
link |
00:54:34.060
and the mammals started populating all of these niches.
link |
00:54:37.460
And in that diversification,
link |
00:54:40.660
there was room for expansion of new types of functions.
link |
00:54:44.740
So some of them populated the air with bats flying,
link |
00:54:50.140
a new evolution of flight.
link |
00:54:53.260
Some populated the oceans with dolphins and whales
link |
00:54:57.460
going off to swim, et cetera.
link |
00:54:58.700
But we all are fundamentally mammals.
link |
00:55:01.380
So you can take the genomes of all these species
link |
00:55:04.220
and align them on top of each other
link |
00:55:06.260
and basically create nucleotide resolution correspondences.
link |
00:55:11.860
What my PhD work showed is that when you do that,
link |
00:55:14.220
when you line up species on top of each other,
link |
00:55:17.180
you can see that within protein coding genes,
link |
00:55:19.860
there's a particular pattern of evolution
link |
00:55:21.980
that is dictated by the level at which
link |
00:55:25.780
evolutionary selection acts.
link |
00:55:27.700
If I'm coding for a protein and I change
link |
00:55:30.700
the third codon position of a triplet
link |
00:55:34.340
that codes for that amino acid,
link |
00:55:36.580
the same amino acid will be encoded.
link |
00:55:38.980
So that basically means that any kind of mutation
link |
00:55:42.020
that preserves that translation that is invariant
link |
00:55:46.140
to that ultimate functional assessment
link |
00:55:49.580
that evolution will give is tolerated.
link |
00:55:52.420
So for any function that you're trying to achieve,
link |
00:55:55.100
there's a set of sequences that encode it.
link |
00:55:57.820
You can now look at the mapping,
link |
00:56:00.380
the graph isomorphism, if you wish,
link |
00:56:04.460
between all of the possible DNA encodings
link |
00:56:07.460
of a particular function and that function.
link |
00:56:09.780
And instead of having just that exact sequence
link |
00:56:12.420
at the protein level, you can think of the set
link |
00:56:15.020
of protein sequences that all fulfill the same function.
link |
00:56:18.020
What's evolution doing?
link |
00:56:19.420
Evolution has two components.
link |
00:56:20.820
One component is random, blind, and stupid mutation.
link |
00:56:25.300
The other component is super smart, ruthless selection.
link |
00:56:32.020
That's my mom calling from Greece.
link |
00:56:35.220
Yes, I might be a fully grown man, but I am a Greek.
link |
00:56:40.060
Did you just cancel the call?
link |
00:56:41.540
Wow, you're in trouble.
link |
00:56:42.380
I know, I'm in trouble.
link |
00:56:43.220
No, she's gonna be calling the cops.
link |
00:56:44.860
Honey, are you okay?
link |
00:56:45.700
I'm gonna edit this clip out and send it to her.
link |
00:56:47.700
Sure.
link |
00:56:51.660
So there's a lot of encoding
link |
00:56:53.060
for the same kind of function.
link |
00:56:54.300
Yeah, so you now have this mapping
link |
00:56:56.620
between all of the set of functions
link |
00:56:58.740
that could all encode the same,
link |
00:57:00.900
all of the set of sequences
link |
00:57:02.180
that can all encode the same function.
link |
00:57:04.260
What evolutionary signatures does
link |
00:57:06.580
is that it basically looks at the shape
link |
00:57:08.980
of that distribution of sequences
link |
00:57:11.180
that all encode the same thing.
link |
00:57:13.060
And based on that shape, you can basically say,
link |
00:57:15.220
ooh, proteins have a very different shape
link |
00:57:17.940
than RNA structures, than regulatory motifs, et cetera.
link |
00:57:21.340
So just by scanning a sequence, ignoring the sequence
link |
00:57:24.500
and just looking at the patterns of change,
link |
00:57:26.740
I'm like, wow, this thing is evolving like a protein
link |
00:57:29.380
and that thing is evolving like a motif
link |
00:57:31.700
and that thing is evolving.
link |
00:57:33.180
So that's exactly what we just did for COVID.
link |
00:57:35.620
So our paper that we posted in bioRxiv about coronavirus
link |
00:57:39.020
basically took this concept of evolutionary signatures
link |
00:57:42.020
and applied it on the SARS CoV2 genome
link |
00:57:45.740
that is responsible for the COVID 19 pandemic.
link |
00:57:48.540
And comparing it to?
link |
00:57:50.540
To 44 serbicovirus species.
link |
00:57:52.460
So this is the beta.
link |
00:57:53.700
What word did you just use, serbicovirus?
link |
00:57:56.220
Serbicovirus, so SARS related beta coronavirus.
link |
00:58:00.460
It's a portmanteau of a bunch.
link |
00:58:01.460
So that whole family of viruses.
link |
00:58:03.060
Yeah, so.
link |
00:58:03.900
How big is that family by the way?
link |
00:58:05.100
We have 44 species that, or I mean.
link |
00:58:07.420
There's 44 species in the family?
link |
00:58:09.340
Yeah. Virus is a clever bunch.
link |
00:58:11.100
No, no, but there's just 44.
link |
00:58:12.900
And again, we don't call them species in viruses.
link |
00:58:15.660
We call them strains.
link |
00:58:16.500
But anyway, there's 44 strains.
link |
00:58:18.260
And that's a tiny little subset of maybe another 50 strains
link |
00:58:22.300
that are just far too distantly related.
link |
00:58:24.460
Most of those only infect bats as the host
link |
00:58:29.060
and a subset of only four or five have ever infected humans.
link |
00:58:34.020
And we basically took all of those
link |
00:58:35.660
and we aligned them in the same exact way
link |
00:58:37.740
that we've aligned mammals.
link |
00:58:39.020
And then we looked at what proteins are,
link |
00:58:42.340
which of the currently hypothesized genes
link |
00:58:44.980
for the coronavirus genome
link |
00:58:47.420
are in fact evolving like proteins and which ones are not.
link |
00:58:50.260
And what we found is that ORF10,
link |
00:58:52.940
the last little open reading frame,
link |
00:58:54.620
the last little gene in the genome is bogus.
link |
00:58:56.980
That's not a protein at all.
link |
00:58:58.700
What is it?
link |
00:58:59.900
It's an RNA structure.
link |
00:59:01.820
That doesn't have a.
link |
00:59:03.540
It doesn't get translated into amino acids.
link |
00:59:05.700
And that, so it's important to narrow down
link |
00:59:08.260
to basically discover what's useful and what's not.
link |
00:59:10.780
Exactly.
link |
00:59:11.620
Basically, what is even the set of genes?
link |
00:59:13.580
The other thing that these evolutionary signatures showed
link |
00:59:15.500
is that within ORF3A lies a tiny little additional gene
link |
00:59:20.660
encoded within the other gene.
link |
00:59:22.700
So you can translate a DNA sequence
link |
00:59:24.540
in three different reading frames.
link |
00:59:26.820
If you start in the first one, it's ATG, et cetera.
link |
00:59:30.100
If you start on the second one, it's TGC, et cetera.
link |
00:59:32.940
And there's a gene within a gene.
link |
00:59:36.620
So there's a whole other protein
link |
00:59:37.860
that we didn't know about that might be super important.
link |
00:59:41.180
So we don't even know the building blocks of SARS COVID 2.
link |
00:59:45.620
So if we want to understand coronavirus biology
link |
00:59:48.300
and eventually find it successfully,
link |
00:59:50.500
we need to even have the set of genes
link |
00:59:51.940
and these evolutionary signatures
link |
00:59:53.660
that I developed in my PhD work.
link |
00:59:55.540
Are you really useful here?
link |
00:59:56.380
We just recently used.
link |
00:59:57.420
You know what, let's run with that tangent
link |
00:59:59.500
for a little bit, if it's okay.
link |
01:00:01.100
Can we talk about the COVID 19 a little bit more?
link |
01:00:08.700
What's your sense about the genome, the proteins,
link |
01:00:13.180
the functions that we understand about COVID 19?
link |
01:00:16.340
Where do we stand in your sense?
link |
01:00:18.900
What are the big open problems?
link |
01:00:21.420
And also, you kind of said it's important to understand
link |
01:00:25.380
what are the important proteins
link |
01:00:29.860
and why is that important?
link |
01:00:34.140
So what else does the comparison of these species tell us?
link |
01:00:39.420
What it tells us is how fast are things evolving?
link |
01:00:43.020
It tells us about at what level is the acceleration
link |
01:00:46.620
or deceleration pedal set for every one of these proteins.
link |
01:00:50.820
So the genome has 30 some genes.
link |
01:00:54.100
Some genes evolve super, super fast.
link |
01:00:56.580
Others evolve super, super slow.
link |
01:00:59.020
If you look at the polymerase gene
link |
01:01:00.460
that basically replicates the genome,
link |
01:01:01.980
that's a super slow evolving one.
link |
01:01:04.220
If you look at the nucleocapsid protein,
link |
01:01:06.340
that's also super slow evolving.
link |
01:01:09.420
If you look at the spike one protein,
link |
01:01:11.460
this is the part of the spike protein
link |
01:01:13.380
that actually touches the ACE2 receptor
link |
01:01:15.740
and then enables the virus to attach to your cells.
link |
01:01:21.300
That's the thing that gives it that visual...
link |
01:01:23.820
Yeah, the corona look basically.
link |
01:01:24.860
The corona look, yeah.
link |
01:01:26.020
So basically the spike protein sticks out of the virus
link |
01:01:28.540
and there's a first part of the protein S1
link |
01:01:31.180
which basically attaches to the ACE2 receptor.
link |
01:01:34.540
And then S2 is the latch that sort of pushes and channels
link |
01:01:39.500
the fusion of the membranes
link |
01:01:41.060
and then the incorporation of the viral RNA inside our cells
link |
01:01:47.060
which then gets translated into all of these 30 proteins.
link |
01:01:50.460
So the S1 protein is evolving ridiculously fast.
link |
01:01:55.460
So if you look at the stop versus gas pedal,
link |
01:01:59.460
the gas pedal is all the way down.
link |
01:02:02.660
ORF8 is also evolving super fast
link |
01:02:05.140
and ORF6 is evolving super fast.
link |
01:02:06.700
We have no idea what they do.
link |
01:02:08.020
We have some idea but nowhere near what S1 is.
link |
01:02:11.340
So what the...
link |
01:02:12.180
Isn't that terrifying that S1 is evolving?
link |
01:02:14.220
That means that's a really useful function
link |
01:02:16.900
and if it's evolving fast,
link |
01:02:18.780
doesn't that mean new strains could be created
link |
01:02:20.700
or it does something?
link |
01:02:21.540
That means that it's searching for how to match,
link |
01:02:24.220
how to best match the host.
link |
01:02:26.700
So basically anything in general in evolution,
link |
01:02:29.260
if you look at genomes,
link |
01:02:30.100
anything that's contacting the environment
link |
01:02:32.300
is evolving much faster than anything that's internal.
link |
01:02:34.980
And the reason is that the environment changes.
link |
01:02:37.140
So if you look at the evolution of the cervical viruses,
link |
01:02:42.180
the S1 protein has evolved very rapidly
link |
01:02:44.420
because it's attaching to different hosts each time.
link |
01:02:47.420
We think of them as bats,
link |
01:02:48.500
but there's thousands of species of bats
link |
01:02:50.540
and to go from one species of bat to another species of bat,
link |
01:02:52.900
you have to adjust S1 to the new ACE2 receptor
link |
01:02:55.940
that you're gonna be facing in that new species.
link |
01:02:58.100
Sorry, quick tangent.
link |
01:02:59.740
Is it fascinating to you that viruses are doing this?
link |
01:03:03.540
I mean, it feels like they're this intelligent organism.
link |
01:03:06.900
I mean, does it give you pause how incredible it is
link |
01:03:12.380
that the evolutionary dynamics that you're describing
link |
01:03:16.500
is actually happening and they're freaking out,
link |
01:03:19.260
figuring out how to jump from bats to humans
link |
01:03:22.180
all in this distributed fashion?
link |
01:03:24.220
And then most of us don't even say
link |
01:03:25.620
they're alive or intelligent or whatever.
link |
01:03:27.660
So intelligence is in the eye of the beholder.
link |
01:03:31.340
Stupid is as stupid does, as Forrest Gump would say,
link |
01:03:34.940
and intelligent is as intelligent does.
link |
01:03:36.580
So basically if the virus is finding solutions
link |
01:03:39.220
that we think of as intelligent,
link |
01:03:40.900
yeah, it's probably intelligent,
link |
01:03:42.260
but that's again in the eye of the beholder.
link |
01:03:43.940
Do you think viruses are intelligent?
link |
01:03:45.700
Oh, of course not.
link |
01:03:47.300
Really?
link |
01:03:48.140
No.
link |
01:03:49.060
It's so incredible.
link |
01:03:50.180
So remember when I was talking about the two components
link |
01:03:52.740
of evolution, one is the stupid mutation,
link |
01:03:55.900
which is completely blind,
link |
01:03:57.100
and the other one is the super smart selection,
link |
01:04:00.260
which is ruthless.
link |
01:04:01.820
So it's not viruses who are smart.
link |
01:04:04.780
It's this component of evolution that's smart.
link |
01:04:06.860
So it's evolution that sort of appears smart.
link |
01:04:10.380
And how is that happening?
link |
01:04:12.020
By huge parallel search across thousands of parallel
link |
01:04:17.020
of parallel infections throughout the world right now.
link |
01:04:21.700
Yes, but so to push back on that,
link |
01:04:23.980
so yes, so then the intelligence is in the mechanism,
link |
01:04:27.980
but then by that argument,
link |
01:04:31.380
viruses would be more intelligent
link |
01:04:32.860
because there's just more of them.
link |
01:04:34.700
So the search, they're basically the brute force search
link |
01:04:38.740
that's happening with viruses
link |
01:04:40.340
because there's so many more of them than humans,
link |
01:04:43.220
then they're taken as a whole are more intelligent.
link |
01:04:47.540
I mean, so you don't think it's possible that,
link |
01:04:51.260
I mean, who runs, would we even be here if viruses weren't,
link |
01:04:55.580
I mean, who runs this thing?
link |
01:04:58.380
So humans or viruses?
link |
01:04:59.700
So let me answer, yeah, let me answer your question.
link |
01:05:03.060
So we would not be here if it wasn't for viruses.
link |
01:05:10.460
And part of the reason is that
link |
01:05:11.820
if you look at mammalian evolution early on
link |
01:05:14.340
in this mammalian radiation
link |
01:05:16.100
that basically happened after the death of the dinosaurs
link |
01:05:18.580
is that some of the viruses that we had in our genome
link |
01:05:22.740
spread throughout our genome
link |
01:05:24.580
and created binding sites
link |
01:05:27.260
for new classes of regulatory proteins.
link |
01:05:30.340
And these binding sites that landed all over our genome
link |
01:05:33.340
are now control elements that basically control our genes
link |
01:05:36.860
and sort of help the complexity of the circuitry
link |
01:05:40.420
of mammalian genomes.
link |
01:05:42.220
So, you know, everything's coevolution.
link |
01:05:45.100
That's fascinating, we're working together.
link |
01:05:47.780
And yet you say they're dumb.
link |
01:05:48.620
We've coopted them.
link |
01:05:49.620
No, I never said they're dumb.
link |
01:05:51.660
They just don't care.
link |
01:05:53.620
They don't care.
link |
01:05:54.980
Another thing, oh, is the virus trying to kill us?
link |
01:05:56.980
No, it's not.
link |
01:05:58.020
The virus is not trying to kill you.
link |
01:05:59.980
It's actually actively trying to not kill you.
link |
01:06:02.820
So when you get infected, if you die,
link |
01:06:05.980
bomber, I killed him,
link |
01:06:07.340
is what the reaction of the virus will be.
link |
01:06:09.140
Why? Because that virus won't spread.
link |
01:06:12.060
Many people have a misconception of,
link |
01:06:13.780
oh, viruses are smart or oh, viruses are mean.
link |
01:06:16.780
They don't care.
link |
01:06:18.620
It's like, you have to clean yourself
link |
01:06:20.780
of any kind of anthropomorphism out there.
link |
01:06:23.300
I don't know.
link |
01:06:24.140
Oh, yes.
link |
01:06:24.980
So there's a sense when taken as a whole that there's...
link |
01:06:31.780
It's in the eye of the beholder.
link |
01:06:32.980
Stupid is as stupid does.
link |
01:06:34.180
Intelligent is as intelligent does.
link |
01:06:35.940
So if you want to call them intelligent, that's fine.
link |
01:06:38.460
Because the end result is that
link |
01:06:40.420
they're finding amazing solutions.
link |
01:06:42.700
I mean, I am in awe.
link |
01:06:44.300
They're so dumb about it.
link |
01:06:45.580
They're just doing dumb.
link |
01:06:46.420
They don't care.
link |
01:06:47.260
They're not dumb and they're just don't care.
link |
01:06:48.580
They don't care.
link |
01:06:50.060
The care word is really interesting.
link |
01:06:51.780
I mean, there could be an argument that they're conscious.
link |
01:06:54.380
They're just dividing.
link |
01:06:55.460
They're not.
link |
01:06:56.300
They're just dividing.
link |
01:06:57.620
They're just a little entity
link |
01:07:00.020
which happens to be dividing and spreading.
link |
01:07:02.660
It just doesn't want to kill us.
link |
01:07:04.420
In fact, it prefers not to kill us.
link |
01:07:06.340
It just wants to spread.
link |
01:07:07.580
And when I say wants, again, I'm anthropomorphizing,
link |
01:07:11.020
but it's just that if you have two versions of a virus,
link |
01:07:15.060
one acquires a mutation that spreads more,
link |
01:07:17.420
that's going to spread more.
link |
01:07:18.620
One acquires a mutation that spreads less,
link |
01:07:20.260
that's going to be lost.
link |
01:07:21.740
One acquires a mutation that enters faster,
link |
01:07:24.020
that's going to be kept.
link |
01:07:25.100
One acquires a mutation that kills you right away,
link |
01:07:27.020
it's going to be lost.
link |
01:07:28.420
So over evolutionary time,
link |
01:07:30.500
the viruses that spread super well
link |
01:07:32.700
but don't kill the host
link |
01:07:33.940
are the ones that are going to survive.
link |
01:07:36.260
Yeah, but so you brilliantly described
link |
01:07:39.060
the basic mechanisms of how it all happens,
link |
01:07:41.060
but when you zoom out and you see the entirety of viruses,
link |
01:07:46.500
maybe across different strains of viruses,
link |
01:07:49.980
it seems like a living organism.
link |
01:07:52.380
I am in awe of biology.
link |
01:07:55.020
I find biology amazingly beautiful.
link |
01:07:58.340
I find the design of the current coronavirus,
link |
01:08:01.100
however lethal it is, amazingly beautiful.
link |
01:08:04.260
The way that it is encoded,
link |
01:08:06.340
the way that it tricks your cells
link |
01:08:08.980
into making 30 proteins from a single RNA.
link |
01:08:12.340
Human cells don't do that.
link |
01:08:14.340
Human cells make one protein from each RNA molecule.
link |
01:08:18.180
They don't make two, they make one.
link |
01:08:20.220
We are hardwired to make only one protein
link |
01:08:22.340
from every RNA molecule.
link |
01:08:23.780
And yet this virus goes in,
link |
01:08:25.700
throws in a single messenger RNA.
link |
01:08:28.700
Just like any messenger RNA,
link |
01:08:29.980
we have tens of thousands of messenger RNAs
link |
01:08:32.140
in our cells in any one time.
link |
01:08:34.140
In every one of our cells.
link |
01:08:35.820
It throws in one RNA and that RNA is so,
link |
01:08:40.620
I'm gonna use your word here, not my word, intelligent.
link |
01:08:44.100
That it hijacks the entire machinery of your human cell.
link |
01:08:49.300
It basically has at the beginning,
link |
01:08:52.500
a giant open reading frame.
link |
01:08:54.460
That's a giant protein that gets translated.
link |
01:08:57.140
Two thirds of that RNA make a single giant protein.
link |
01:09:01.540
That single protein is basically
link |
01:09:03.340
what a human cell would make.
link |
01:09:04.540
It's like, oh, here's a start code.
link |
01:09:06.340
I'm gonna start translating here.
link |
01:09:07.700
Human cells are kind of dumb.
link |
01:09:08.620
I'm sorry.
link |
01:09:09.460
Again, this is not the words I would normally use.
link |
01:09:12.420
But the human cell basically says,
link |
01:09:13.420
oh, this is an RNA, must be mine.
link |
01:09:15.020
Let me translate.
link |
01:09:15.860
And it starts translating it.
link |
01:09:17.020
And then you're in trouble.
link |
01:09:18.460
Why?
link |
01:09:19.300
Because that one protein as it's growing,
link |
01:09:22.380
gets cleaved into about 20 different peptides.
link |
01:09:26.980
The first peptide and the second peptide start interacting
link |
01:09:30.940
and the third one and the fourth one.
link |
01:09:32.460
And they shut off the ribosome of the whole cell
link |
01:09:37.820
to not translate human RNAs anymore.
link |
01:09:42.820
So the virus basically hijacks your cells
link |
01:09:46.580
and it cuts, it cleaves every one of your human RNAs
link |
01:09:50.820
to basically say to the ribosome,
link |
01:09:52.100
don't translate this one, junk.
link |
01:09:53.500
Don't look at this one, junk.
link |
01:09:55.140
And it only spares its own RNAs
link |
01:09:58.740
because they have a particular mark that it spares.
link |
01:10:01.300
Then all of the ribosomes that normally make protein
link |
01:10:04.380
in your human cells are now only able
link |
01:10:06.860
to translate viral RNAs.
link |
01:10:09.220
And then more and more and more and more of them.
link |
01:10:11.460
That's the first 20 proteins.
link |
01:10:13.100
In fact, halfway down about protein 11,
link |
01:10:16.300
between 11 and 12,
link |
01:10:17.940
you basically have a translational slippage
link |
01:10:21.020
where the ribosome skips reading frame.
link |
01:10:23.420
And it translates from one reading frame
link |
01:10:24.980
to another reading frame.
link |
01:10:25.820
That means that about half of them
link |
01:10:27.100
are gonna be translated from one to 11.
link |
01:10:29.260
And the other half are gonna be translated
link |
01:10:30.900
from 12 to 16.
link |
01:10:32.700
It's gorgeous.
link |
01:10:34.260
And then you're done.
link |
01:10:37.380
Then that mRNA will never translate the last 10 proteins
link |
01:10:40.420
but spike is the one right after that one.
link |
01:10:42.540
So how does spike even get translated?
link |
01:10:45.140
This positive strand RNA virus has a reverse transcriptase
link |
01:10:50.020
which is an RNA based reverse transcriptase.
link |
01:10:52.340
So from the RNA on the positive strand,
link |
01:10:54.460
it makes an RNA on the negative strand.
link |
01:10:56.940
And in between every single one of these genes,
link |
01:10:59.620
these open reading frames,
link |
01:11:01.060
there's a little signal AACGCA or something like that,
link |
01:11:05.580
that basically loops over to the beginning of the RNA.
link |
01:11:09.940
And basically instead of sort of having
link |
01:11:11.700
a single full negative strand RNA,
link |
01:11:14.500
it basically has a partial negative strand RNA
link |
01:11:16.860
that ends right before the beginning of that gene.
link |
01:11:19.700
And another one that ends right before
link |
01:11:20.860
the beginning of that gene.
link |
01:11:21.980
These negative strand RNAs now make positive strand RNAs
link |
01:11:25.340
that then look to the human whole cell
link |
01:11:27.460
just like any other human mRNA.
link |
01:11:29.780
It's like, ooh, great, I'm gonna translate that one
link |
01:11:31.780
because it doesn't have the cleaving
link |
01:11:32.980
that the virus has now put on all your human genes.
link |
01:11:36.340
And then you've lost the battle.
link |
01:11:38.300
That cell is now only making proteins for the virus
link |
01:11:42.500
that will then create the spike protein,
link |
01:11:45.500
the envelope protein, the membrane protein,
link |
01:11:47.620
the nucleocapsid protein that will package up the RNA
link |
01:11:50.380
and then sort of create new viral envelopes.
link |
01:11:53.820
And these will then be secreted out of that cell
link |
01:11:57.780
in new little packages
link |
01:11:59.260
that will then infect the rest of the cells.
link |
01:12:00.580
Repeat the whole process again.
link |
01:12:01.980
It's beautiful, right?
link |
01:12:03.300
It's mind boggling.
link |
01:12:04.140
It's hard not to anthropomorphize it.
link |
01:12:05.620
I know, but it's so gorgeous.
link |
01:12:08.100
So there is a beauty to it.
link |
01:12:09.900
Of course.
link |
01:12:12.140
Is it terrifying to you?
link |
01:12:13.980
So this is something that has happened throughout history.
link |
01:12:16.940
Humans have been nearly wiped out
link |
01:12:19.700
over and over and over again,
link |
01:12:21.140
and yet never fully wiped out.
link |
01:12:23.260
So yeah, I'm not concerned about the human race.
link |
01:12:25.940
I'm not even concerned about the impact
link |
01:12:29.340
on sort of our survival as a species.
link |
01:12:33.780
This is absolutely something,
link |
01:12:35.620
I mean, human life is so invaluable
link |
01:12:38.660
and every one of us is so invaluable,
link |
01:12:40.060
but if you think of it as sort of,
link |
01:12:42.260
is this the end of our species?
link |
01:12:44.100
By no means, basically.
link |
01:12:46.420
So let me explain.
link |
01:12:48.100
The Black Death killed what, 30% of Europe?
link |
01:12:51.260
That has left a tremendous imprint,
link |
01:12:55.260
a huge hole, a horrendous hole
link |
01:12:59.260
in the genetic makeup of humans.
link |
01:13:03.620
There's been series of wiping out of huge fractions
link |
01:13:08.620
of entire species or just entire species altogether.
link |
01:13:12.180
And that has a consequence on the human immune repertoire.
link |
01:13:17.180
If you look at how Europe was shaped
link |
01:13:20.860
and how Africa was shaped by malaria, for example,
link |
01:13:24.700
all the individuals that carry a mutation
link |
01:13:26.940
that protects you from malaria
link |
01:13:29.220
were able to survive much more.
link |
01:13:31.100
And if you look at the frequency of sickle cell disease
link |
01:13:33.820
and the frequency of malaria,
link |
01:13:35.580
the maps are actually showing the same pattern,
link |
01:13:38.340
the same imprint on Africa.
link |
01:13:40.420
And that basically led people to hypothesize
link |
01:13:42.340
that the reason why sickle cell disease
link |
01:13:43.860
is so much more frequent is because
link |
01:13:45.660
sickle cell disease is so much more frequent
link |
01:13:47.620
in Americans of African descent
link |
01:13:50.060
is because there was selection in Africa against malaria
link |
01:13:55.260
leading to sickle cell, because when the cells sickle,
link |
01:13:57.780
malaria is not able to replicate inside your cells as well.
link |
01:14:01.380
And therefore you protect against that.
link |
01:14:03.060
So if you look at human disease,
link |
01:14:05.380
all of the genetic associations that we do
link |
01:14:07.540
with human disease,
link |
01:14:09.220
you basically see the imprint
link |
01:14:13.620
of these waves of selection killing off
link |
01:14:16.620
gazillions of humans.
link |
01:14:18.300
And there's so many immune processes that are coming up
link |
01:14:23.180
as associated with so many different diseases.
link |
01:14:25.900
The reason for that is similar
link |
01:14:27.500
to what I was describing earlier,
link |
01:14:28.620
where the outward facing proteins evolve much more rapidly
link |
01:14:33.620
because the environment is always changing.
link |
01:14:35.860
But what's really interesting in the human genome
link |
01:14:37.620
is that we have coopted many of these immune genes
link |
01:14:40.340
to carry out nonimmune functions.
link |
01:14:42.420
For example, in our brain,
link |
01:14:43.980
we use immune cells to cleave off neuronal connections
link |
01:14:48.860
that don't get used.
link |
01:14:50.140
This whole use it or lose it, we know the mechanism.
link |
01:14:52.820
It's microglia that cleave off neuronal synaptic connections
link |
01:14:57.820
that are just not utilized.
link |
01:14:59.900
When you utilize them, you mark them in a particular way
link |
01:15:02.020
that basically when the microglia come,
link |
01:15:04.380
tell it, don't kill this one, it's used now.
link |
01:15:07.820
And the microglia will go off
link |
01:15:08.940
and kill the ones you don't use.
link |
01:15:10.340
This is an immune function,
link |
01:15:12.780
which is coopted to do nonimmune things.
link |
01:15:14.980
If you look at our adipocytes,
link |
01:15:16.780
M1 versus M2 macrophages inside our fat
link |
01:15:19.900
will basically determine whether you're obese or not.
link |
01:15:22.620
And these are again, immune cells that are resident
link |
01:15:24.740
and living within these tissues.
link |
01:15:27.060
So many disease associations.
link |
01:15:30.220
That's it, that we coopt these kinds of things
link |
01:15:33.660
for incredibly complicated functions.
link |
01:15:36.660
Exactly, evolution works in so many different ways,
link |
01:15:39.860
which are all beautiful and mysterious.
link |
01:15:41.980
But not intelligent.
link |
01:15:43.340
Not intelligent, it's in the eye of the beholder.
link |
01:15:45.740
But the point that I'm trying to make is that
link |
01:15:51.060
if you look at the imprint that COVID will have,
link |
01:15:54.260
hopefully it will not be big.
link |
01:15:55.980
Hopefully the US will get attacked together
link |
01:15:57.980
and stop the virus from spreading further.
link |
01:16:00.420
But if it doesn't, it's having an imprint
link |
01:16:03.500
on individuals who have particular genetic repertoires.
link |
01:16:07.340
So if you look at now the genetic associations
link |
01:16:10.060
of blood type and immune function cells, et cetera,
link |
01:16:13.620
there's actually association, genetic variation
link |
01:16:15.740
that basically says how much more likely am I or you to die
link |
01:16:18.540
if we contact the virus.
link |
01:16:20.220
And it's through these rounds of shaping the human genome
link |
01:16:24.540
that humans have basically made it so far.
link |
01:16:27.380
And selection is ruthless and it's brutal
link |
01:16:32.620
and it only comes with a lot of killing.
link |
01:16:34.380
But this is the way that viruses and environments
link |
01:16:38.140
have shaped the human genome.
link |
01:16:39.540
Basically, when you go through periods of famine,
link |
01:16:41.420
you select for particular genes.
link |
01:16:43.660
And what's left is not necessarily better,
link |
01:16:46.540
it's just whatever survived.
link |
01:16:49.020
And it might have been the surviving one back then,
link |
01:16:51.980
not because it was better,
link |
01:16:53.140
maybe the ones that ran slower survived.
link |
01:16:54.980
I mean, again, not necessarily better,
link |
01:16:57.420
but the surviving ones are basically the ones
link |
01:17:00.020
that then are shaped for any kind
link |
01:17:02.420
of subsequent evolutionary condition
link |
01:17:05.420
and environmental condition.
link |
01:17:07.260
But if you look at, for example, obesity,
link |
01:17:09.580
obesity was selected for basically the genes
link |
01:17:12.420
that now predisposes to obesity
link |
01:17:14.420
were at 2% frequency in Africa.
link |
01:17:16.660
They rose to 44% frequency in Europe.
link |
01:17:19.020
Wow, that's fascinating.
link |
01:17:20.300
Because you basically went through the ice ages
link |
01:17:22.940
and there was a scarcity of food.
link |
01:17:24.620
So there was a selection to being able to store
link |
01:17:27.140
every single calorie you consume.
link |
01:17:29.260
Eventually, environment changes.
link |
01:17:31.860
So the better allele, which was the fat storing allele,
link |
01:17:35.140
became the worst allele
link |
01:17:36.500
because it's the fat storing allele.
link |
01:17:38.780
It still has the same function.
link |
01:17:40.940
So if you look at my genome, speaking of mom calling,
link |
01:17:44.100
mom gave me a bad copy of that gene, this FTO locus.
link |
01:17:48.500
Basically, makes me.
link |
01:17:49.340
The one that has to do with.
link |
01:17:50.460
Obesity.
link |
01:17:51.300
With obesity.
link |
01:17:52.140
Yeah, I basically now have a bad copy from mom
link |
01:17:54.500
that makes me more likely to be obese.
link |
01:17:56.340
And I also have a bad copy from dad
link |
01:17:59.180
that makes me more likely to be obese.
link |
01:18:00.020
So homozygous.
link |
01:18:01.860
And that's the allele, it's still the minor allele,
link |
01:18:05.860
but it's at 44% frequency in Southeast Asia,
link |
01:18:09.140
42% frequency in Europe, even though it started at 2%.
link |
01:18:12.740
It was an awesome allele to have 100 years ago.
link |
01:18:16.060
Right now, it's pretty terrible allele.
link |
01:18:17.900
So the other concept is that diversity matters.
link |
01:18:21.980
If we had 100 million nuclear physicists
link |
01:18:25.660
living the earth right now, we'd be in trouble.
link |
01:18:28.420
You need diversity, you need artists
link |
01:18:31.820
and you need musicians and you need mathematicians
link |
01:18:33.980
and you need politicians, yes, even those.
link |
01:18:37.100
And you need like.
link |
01:18:37.940
Well, let's not get crazy.
link |
01:18:39.580
But because then if a virus comes along or whatever.
link |
01:18:43.100
Exactly, exactly.
link |
01:18:44.900
So, no, there's two reasons.
link |
01:18:45.980
Number one, you want diversity in the immune repertoire
link |
01:18:48.820
and we have built in diversity.
link |
01:18:50.820
So basically, they are the most diverse.
link |
01:18:53.380
Basically, if you look at our immune system,
link |
01:18:54.900
there's layers and layers of diversity.
link |
01:18:57.100
Like the way that you create your cells generates diversity
link |
01:19:01.540
because of the selection for the VDJ recombination
link |
01:19:04.820
that basically eventually leads
link |
01:19:06.580
to a huge number of repertoires.
link |
01:19:08.140
But that's only one small component of diversity.
link |
01:19:10.220
The blood type is another one.
link |
01:19:11.540
The major histocompatibility complex, the HLA alleles
link |
01:19:15.900
are another source of diversity.
link |
01:19:18.020
So the immune system of humans is by nature,
link |
01:19:21.660
incredibly diverse and that basically leads to resilience.
link |
01:19:25.580
So basically what I'm saying that I don't worry
link |
01:19:27.460
for the human species because we are so diverse immunologically,
link |
01:19:32.460
we are likely to be very resilient
link |
01:19:34.860
against so many different attacks like this current virus.
link |
01:19:39.020
So you're saying natural pandemics may not be something
link |
01:19:42.100
that you're really afraid of because of the diversity
link |
01:19:45.180
in our genetic makeup.
link |
01:19:48.380
What about engineered pandemics?
link |
01:19:50.380
Do you have fears of us messing with the makeup of viruses
link |
01:19:55.740
or well, yeah, let's say with the makeup of viruses
link |
01:19:58.860
to create something that we can't control
link |
01:20:00.820
and would be much more destructive
link |
01:20:02.700
than it would come about naturally?
link |
01:20:05.300
Remember how we were talking about how smart evolution is?
link |
01:20:08.020
Humans are much dumber.
link |
01:20:09.300
So.
link |
01:20:10.140
You mean like human scientists, engineers?
link |
01:20:11.860
Yeah, humans, humans just like.
link |
01:20:13.180
Humans overall?
link |
01:20:14.020
Yeah, humans overall.
link |
01:20:14.860
Okay.
link |
01:20:15.700
But I mean, even the sort of synthetic biologists
link |
01:20:19.660
you know, basically if you were to create,
link |
01:20:25.700
you know, virus like SARS that will kill a lot of people,
link |
01:20:29.700
you would probably start with SARS.
link |
01:20:32.860
So whoever, you know, would like to design such a thing
link |
01:20:37.460
would basically start with a SARS tree
link |
01:20:39.980
or at least some relative of SARS.
link |
01:20:42.460
The source genome for the current virus
link |
01:20:45.580
was something completely different.
link |
01:20:47.140
It was something that has never infected anyone
link |
01:20:49.100
and never infected humans.
link |
01:20:50.620
No one in their right mind would have started there.
link |
01:20:52.900
But when you say sources like the nearest.
link |
01:20:55.020
The nearest relative.
link |
01:20:56.260
Relative.
link |
01:20:57.100
Is in a whole other branch.
link |
01:20:58.420
Interesting.
link |
01:20:59.260
No species of which has ever infected humans
link |
01:21:00.980
in that branch.
link |
01:21:02.580
So, you know, let's put this to rest.
link |
01:21:05.340
This was not designed by someone to kill off the human race.
link |
01:21:08.580
So you don't believe it was engineered?
link |
01:21:12.020
The. Or likely.
link |
01:21:13.100
Yeah, the path to engineering a deadly virus
link |
01:21:16.140
did not come from this strain that was used.
link |
01:21:21.220
Moreover, there's been various claims of,
link |
01:21:26.940
ha ha, this was mixed and matched in lab
link |
01:21:29.300
because the S1 protein has three different components,
link |
01:21:32.580
each of which has a different evolutionary tree.
link |
01:21:34.700
So, you know, a lot of popular press basically said,
link |
01:21:37.300
aha, this came from pangolin
link |
01:21:39.260
and this came from, you know, all kinds of other species.
link |
01:21:42.980
This is what has been happening
link |
01:21:44.900
throughout the coronavirus tree.
link |
01:21:46.900
So basically the S1 protein has been recombining
link |
01:21:49.380
across species all the time.
link |
01:21:50.420
Remember when I was talking about the positive strand,
link |
01:21:52.020
the negative strand, sub genomic RNAs,
link |
01:21:54.340
these can actually recombine.
link |
01:21:55.780
And if you have two different viruses
link |
01:21:57.140
infecting the same cell,
link |
01:21:58.540
they can actually mix and match
link |
01:21:59.780
between the positive strand and the negative strand
link |
01:22:01.340
and basically create a new hybrid virus with recombination
link |
01:22:04.700
that now has the S1 from one
link |
01:22:06.700
and the rest of the genome from another.
link |
01:22:08.780
And this is something that happens a lot in S1,
link |
01:22:10.580
in Orfet, et cetera.
link |
01:22:12.060
And that's something that's true of the whole tree.
link |
01:22:13.940
For the whole family of viruses.
link |
01:22:15.780
So it's not like someone has been messing with this
link |
01:22:18.020
for millions of years and, you know, changing.
link |
01:22:20.860
This happens naturally.
link |
01:22:21.700
That's, again, beautiful that that somehow happens,
link |
01:22:24.420
that they recombine.
link |
01:22:25.900
So two different strands can infect the body
link |
01:22:27.740
and then recombine.
link |
01:22:30.460
So all of this actually magic happens inside hosts.
link |
01:22:35.100
Like all, like.
link |
01:22:36.300
Yeah, that's why classification wise,
link |
01:22:39.220
virus is not thought to be alive
link |
01:22:40.700
because it doesn't self replicate.
link |
01:22:41.940
It's not autonomous.
link |
01:22:43.020
It's something that enters a living cell
link |
01:22:45.740
and then co ops it to basically make it its own.
link |
01:22:48.740
But by itself, people ask me,
link |
01:22:50.660
how do we kill this bastard?
link |
01:22:51.580
I'm like, you stop it from replicating.
link |
01:22:54.180
It's not like a bacterium that will just live
link |
01:22:57.660
in a, you know, puddle or something.
link |
01:23:01.060
It's a virus.
link |
01:23:02.460
Viruses don't live without their host.
link |
01:23:04.420
And they only live with their host for very little time.
link |
01:23:07.380
So if you stop it from replicating,
link |
01:23:09.100
it'll stop from spreading.
link |
01:23:11.260
I mean, it's not like HIV, which can stay dormant
link |
01:23:13.220
for a long time.
link |
01:23:14.060
Basically, coronaviruses just don't do that.
link |
01:23:15.580
They're not integrating genomes.
link |
01:23:16.780
They're RNA genomes.
link |
01:23:18.060
So if it's not expressed, it degrades.
link |
01:23:20.220
RNA degrades.
link |
01:23:21.180
It doesn't just stick around.
link |
01:23:23.380
Well, let me ask also about the immune system you mentioned.
link |
01:23:27.340
A lot of people kind of ask, you know,
link |
01:23:31.500
how can we strengthen the immune system
link |
01:23:34.140
to respond to this particular virus,
link |
01:23:36.300
but the viruses in general.
link |
01:23:37.740
Do you have from a biological perspective,
link |
01:23:40.420
thoughts on what we can do as humans
link |
01:23:43.140
to strengthen our immune system?
link |
01:23:43.980
If you look at the death rates across different countries,
link |
01:23:46.620
people with less vaccination have been dying more.
link |
01:23:49.700
If you look at North Italy,
link |
01:23:51.380
the vaccination rates are abysmal there.
link |
01:23:53.940
And a lot of people have been dying.
link |
01:23:55.860
If you look at Greece, very good vaccination rates.
link |
01:23:58.780
Almost no one has been dying.
link |
01:24:00.300
So yes, there's a policy component.
link |
01:24:03.580
So Italy reacted very slowly.
link |
01:24:05.980
Greece reacted very fast.
link |
01:24:07.460
So yeah, many fewer people died in Greece,
link |
01:24:09.780
but there might actually be a component
link |
01:24:11.740
of genetic immune repertoire.
link |
01:24:14.100
Basically, how did people die off, you know,
link |
01:24:16.700
in the history of the Greek population
link |
01:24:19.020
versus the Italian population.
link |
01:24:20.740
Wow. There's a...
link |
01:24:22.300
That's interesting to think about.
link |
01:24:24.580
And then there's a component
link |
01:24:25.980
of what vaccinations did you have as a kid
link |
01:24:28.940
and what are the off target effects of those vaccinations?
link |
01:24:32.460
So basically a vaccination can have two components.
link |
01:24:34.900
One is training your immune system
link |
01:24:37.620
against that specific insult.
link |
01:24:39.500
The second one is boosting up your immune system
link |
01:24:42.140
for all kinds of other things.
link |
01:24:44.580
If you look at allergies,
link |
01:24:47.100
Northern Europe, super clean environments,
link |
01:24:50.220
tons of allergies.
link |
01:24:51.420
Southern Europe, my kids grew up eating dirt.
link |
01:24:54.980
No allergies.
link |
01:24:57.060
So growing up, I never had even heard of what allergies are.
link |
01:25:00.420
Like, was it really allergies?
link |
01:25:01.940
And the reason is that I was playing in the garden.
link |
01:25:03.580
I was putting all kinds of stuff in my mouth from,
link |
01:25:05.940
you know, all kinds of dirt and stuff,
link |
01:25:07.380
tons of viruses there, tons of bacteria there.
link |
01:25:09.620
You know, my immune system was built up.
link |
01:25:11.500
So the more you protect your immune system from exposure,
link |
01:25:16.700
the less opportunity it has to learn
link |
01:25:18.820
about non self repertoire in a way that prepares it
link |
01:25:23.100
for the next insult.
link |
01:25:24.380
So that's the horizontal thing too,
link |
01:25:25.860
like the, so it's throughout your lifetime
link |
01:25:28.100
and the lifetime of the people that, your ancestors,
link |
01:25:33.220
that kind of thing.
link |
01:25:34.060
What about the...
link |
01:25:35.060
So again, it returns against free will.
link |
01:25:37.900
On the free will side of things,
link |
01:25:39.540
is there something we could do
link |
01:25:40.980
to strengthen our immune system in 2020?
link |
01:25:44.780
Is there like, you know, exercise, diet,
link |
01:25:49.100
all that kind of stuff?
link |
01:25:50.700
So it's kind of funny.
link |
01:25:52.900
There's a cartoon that basically shows two windows
link |
01:25:55.940
with a teller in each window.
link |
01:25:58.300
One has a humongous line and the other one has no one.
link |
01:26:02.220
The one that has no one above says health.
link |
01:26:04.700
No, it says exercise and diet.
link |
01:26:07.220
And the other one says pill.
link |
01:26:10.300
And there's a huge line for pill.
link |
01:26:12.140
So we're looking basically for magic bullets
link |
01:26:13.940
for sort of ways that we can, you know,
link |
01:26:16.860
beat cancer and beat coronavirus and beat this
link |
01:26:18.980
and beat that.
link |
01:26:19.820
And it turns out that the window with like,
link |
01:26:21.420
just diet and exercise is the best way
link |
01:26:23.980
to boost every aspect of your health.
link |
01:26:26.100
If you look at Alzheimer's, exercise and nutrition.
link |
01:26:31.220
I mean, you're like, really?
link |
01:26:32.580
For my brain, neurodegeneration?
link |
01:26:34.700
Absolutely.
link |
01:26:36.140
If you look at cancer, exercise and nutrition.
link |
01:26:40.420
If you look at coronavirus, exercise and nutrition,
link |
01:26:43.780
every single aspect of human health gets improved.
link |
01:26:47.300
And one of the studies we're doing now
link |
01:26:48.620
is basically looking at what are the effects
link |
01:26:51.260
of diet and exercise?
link |
01:26:52.940
How similar are they to each other?
link |
01:26:55.340
We basically take in diet intervention
link |
01:26:58.220
and exercise intervention in human and in mice.
link |
01:27:01.380
And we're basically doing single cell profiling
link |
01:27:03.580
of a bunch of different tissues
link |
01:27:04.980
to basically understand how are the cells,
link |
01:27:08.020
both the stromal cells and the immune cells
link |
01:27:10.900
of each of these tissues responding
link |
01:27:13.260
to the effect of exercise.
link |
01:27:15.100
What are the communication networks
link |
01:27:16.900
between different cells?
link |
01:27:18.540
Where the muscle that exercises sends signals
link |
01:27:23.900
through the bloodstream, through the lymphatic system,
link |
01:27:25.980
through all kinds of other systems
link |
01:27:27.660
that give signals to other cells that I have exercised
link |
01:27:31.580
and you should change in this particular way,
link |
01:27:33.980
which basically reconfigure those receptor cells
link |
01:27:37.620
with the effect of exercise.
link |
01:27:39.860
How well understood is those reconfigurations?
link |
01:27:43.860
Very little.
link |
01:27:44.700
We're just starting now, basically.
link |
01:27:46.940
Is the hope there to understand the effect on,
link |
01:27:52.420
so like the effect on the immune system?
link |
01:27:54.300
On the immune system, the effect on brain,
link |
01:27:56.220
the effect on your liver, on your digestive system,
link |
01:27:59.060
on your adipocytes?
link |
01:28:00.900
Adipose, the most misunderstood organ.
link |
01:28:03.620
Everybody thinks, oh, fat, terrible.
link |
01:28:05.780
No, fat is awesome.
link |
01:28:07.460
Your fat cells is what's keeping you alive
link |
01:28:09.940
because if you didn't have your fat cells,
link |
01:28:11.420
all those lipids and all those calories
link |
01:28:13.940
would be floating around in your blood
link |
01:28:15.420
and you'd be dead by now.
link |
01:28:16.940
Your adipocytes are your best friend.
link |
01:28:18.460
They're basically storing all these excess calories
link |
01:28:21.820
so that they don't hurt all of the rest of the body.
link |
01:28:24.900
And they're also fat burning in many ways.
link |
01:28:28.940
So, again, when you don't have
link |
01:28:31.540
the homozygous version that I have,
link |
01:28:33.460
your cells are able to burn calories much more easily
link |
01:28:36.500
by sort of flipping a master metabolic switch
link |
01:28:39.980
that involves this FTO locus that I mentioned earlier
link |
01:28:42.380
and its target genes, RX3 and RX5,
link |
01:28:45.060
that basically switch your adipocytes
link |
01:28:47.540
during their three first days of differentiation
link |
01:28:50.780
as they're becoming mature adipocytes
link |
01:28:52.300
to basically become either fat burning
link |
01:28:54.340
or fat storing fat cells.
link |
01:28:57.100
And the fat burning fat cells are your best friend.
link |
01:28:58.980
They're much closer to muscle
link |
01:29:00.460
than they are to white adipocytes.
link |
01:29:02.820
Is there a lot of difference between people
link |
01:29:05.340
that you could give, science could eventually give advice
link |
01:29:09.540
that is very generalizable
link |
01:29:12.260
or is our differences in our genetic makeup,
link |
01:29:16.100
like you mentioned, is that going to be basically
link |
01:29:18.700
something we have to be very specialized individuals,
link |
01:29:22.800
any advice we give in terms of diet,
link |
01:29:24.900
like what we were just talking about?
link |
01:29:25.740
Believe it or not, the most personalized advice
link |
01:29:28.380
that you give for nutrition
link |
01:29:29.620
don't have to do with your genome.
link |
01:29:31.460
They have to do with your gut microbiome,
link |
01:29:34.420
with the bacteria that live inside you.
link |
01:29:35.900
So most of your digestion is actually happening
link |
01:29:37.940
by species that are not human inside you.
link |
01:29:40.800
You have more nonhuman cells than you have human cells.
link |
01:29:43.060
You're basically a giant bag of bacteria
link |
01:29:46.740
with a few human cells along.
link |
01:29:48.320
And those do not necessarily have to do
link |
01:29:53.120
with your genetic makeup.
link |
01:29:54.900
They interact with your genetic makeup.
link |
01:29:56.760
They interact with your epigenome.
link |
01:29:58.000
They interact with your nutrition.
link |
01:29:59.600
They interact with your environment.
link |
01:30:01.280
They're basically an additional source of variation.
link |
01:30:07.000
So when you're thinking about sort of
link |
01:30:08.120
personalized nutritional advice,
link |
01:30:10.080
part of that is actually how do you match your microbiome?
link |
01:30:13.640
And part of that is how do we match your genetics?
link |
01:30:17.080
But again, this is a very diverse set of contributors.
link |
01:30:22.160
And the effect sizes are not enormous.
link |
01:30:24.640
So I think the science for that is not fully developed yet.
link |
01:30:27.920
Speaking of diets,
link |
01:30:28.760
because I've wrestled in combat sports,
link |
01:30:30.640
but sports my whole life were weight matters.
link |
01:30:32.640
So you have to cut and all that stuff.
link |
01:30:35.340
One thing I've learned a lot about my body,
link |
01:30:38.240
and it seems to be, I think,
link |
01:30:39.900
true about other people's bodies,
link |
01:30:41.680
is that you can adjust to a lot of things.
link |
01:30:45.120
That's the miraculous thing about this biological system,
link |
01:30:48.280
is like I fast often.
link |
01:30:52.360
I used to eat like five, six times a day
link |
01:30:54.920
and thought that was absolutely necessary.
link |
01:30:57.020
How could you not eat that often?
link |
01:30:58.960
And then when I started fasting,
link |
01:31:01.320
your body adjusted to that.
link |
01:31:02.720
And you learn how to not eat.
link |
01:31:04.360
And it was, if you just give it a chance
link |
01:31:07.600
for a few weeks, actually,
link |
01:31:09.140
over a period of a few weeks,
link |
01:31:10.320
your body can adjust to anything.
link |
01:31:11.800
And that's a miraculous, that's such a beautiful thing.
link |
01:31:14.120
So I'm a computer scientist,
link |
01:31:15.480
and I've basically gone through periods of 24 hours
link |
01:31:18.040
without eating or stopping.
link |
01:31:19.680
And then I'm like, oh, must eat.
link |
01:31:22.080
And I eat a ton.
link |
01:31:23.080
I used to order two pizzas just with my brother.
link |
01:31:27.440
So I've gone through these extremes as well,
link |
01:31:29.720
and I've gone the whole intermittent fasting thing.
link |
01:31:32.160
So I can sympathize with you both on the seven meals a day
link |
01:31:35.200
to the zero meals a day.
link |
01:31:37.580
So I think when I say everything with moderation,
link |
01:31:40.820
I actually think your body responds interestingly
link |
01:31:44.400
to these different changes in diet.
link |
01:31:47.400
I think part of the reason why we lose weight
link |
01:31:49.920
with pretty much every kind of change in behavior
link |
01:31:52.220
is because our epigenome and the set of proteins
link |
01:31:55.960
and enzymes that are expressed and our microbiome
link |
01:31:58.640
are not well suited to that nutritional source.
link |
01:32:02.080
And therefore, they will not be able
link |
01:32:03.880
to sort of catch everything that you give them.
link |
01:32:06.680
And then a lot of that will go undigested.
link |
01:32:09.160
And that basically means that your body can then
link |
01:32:11.920
lose weight in the short term,
link |
01:32:13.200
but very quickly will adjust to that new normal.
link |
01:32:16.160
And then we'll be able to sort of perhaps gain
link |
01:32:18.200
a lot of weight from the diet.
link |
01:32:20.400
So anyway, I mean, there's also studies in factories
link |
01:32:24.400
where basically people dim the lights
link |
01:32:27.200
and then suddenly everybody started working better.
link |
01:32:28.720
It was like, wow, that's amazing.
link |
01:32:30.160
Three weeks later, they made the lights a little brighter.
link |
01:32:32.840
Everybody started working better.
link |
01:32:34.360
So any kind of intervention has a placebo effect of,
link |
01:32:39.440
wow, now I'm healthier and I'm gonna be running
link |
01:32:41.320
more often, et cetera.
link |
01:32:42.160
So it's very hard to uncouple the placebo effect
link |
01:32:44.600
of, wow, I'm doing something to intervene on my diet
link |
01:32:47.080
from the, wow, this is actually the right thing for me.
link |
01:32:50.280
So, you know.
link |
01:32:51.120
Yeah, from the perspective from a nutrition science,
link |
01:32:53.200
psychology, both things I'm interested in,
link |
01:32:55.760
especially psychology, it seems that it's extremely difficult
link |
01:32:59.560
to do good science because there's so many variables
link |
01:33:03.440
involved, it's so difficult to control the variables,
link |
01:33:06.560
so difficult to do sufficiently large scale experiments,
link |
01:33:10.280
both sort of in terms of the number of subjects
link |
01:33:12.840
and temporal, like how long you do the study for,
link |
01:33:17.040
that it just seems like it's not even a real science
link |
01:33:20.720
for now, like nutrition science.
link |
01:33:22.640
I wanna jump into the whole placebo effect
link |
01:33:24.840
for a little bit here.
link |
01:33:25.840
And basically talk about the implications of that.
link |
01:33:30.200
If I give you a sugar pill and I tell you it's a sugar pill,
link |
01:33:33.400
you won't get any better.
link |
01:33:35.520
But if I tell you a sugar pill and I tell you,
link |
01:33:38.240
wow, this is an amazing drug,
link |
01:33:40.000
it actually will stop your cancer,
link |
01:33:42.240
your cancer will actually stop with much higher probability.
link |
01:33:46.280
What does that mean?
link |
01:33:47.120
That's so amazing.
link |
01:33:47.960
That means that if I can trick your brain
link |
01:33:49.920
into thinking that I'm healing you,
link |
01:33:51.840
your brain will basically figure out a way to heal itself,
link |
01:33:54.560
to heal the body.
link |
01:33:55.920
And that tells us that there's so much
link |
01:33:58.600
that we don't understand in the interplay
link |
01:34:01.440
between our cognition and our biology,
link |
01:34:05.320
that if we were able to better harvest
link |
01:34:08.400
the power of our brain to sort of impact the body
link |
01:34:12.320
through the placebo effect,
link |
01:34:14.200
we would be so much better in so many different things.
link |
01:34:17.280
Just by tricking yourself into thinking
link |
01:34:19.200
that you're doing better, you're actually doing better.
link |
01:34:21.560
So there's something to be said
link |
01:34:22.640
about sort of positive thinking, about optimism,
link |
01:34:25.040
about sort of just getting your brain
link |
01:34:30.040
and your mind into the right mindset
link |
01:34:33.000
that helps your body and helps your entire biology.
link |
01:34:36.920
Yeah, from a science perspective, that's just fascinating.
link |
01:34:39.840
Obviously most things about the brain
link |
01:34:41.600
is a total mystery for now,
link |
01:34:43.640
but that's a fascinating interplay
link |
01:34:46.160
that the brain can help cure cancer.
link |
01:34:54.240
I don't even know what to do with that.
link |
01:34:55.840
I mean, the way to think about that is the following.
link |
01:34:59.120
The converse of the equation is something
link |
01:35:01.240
that we are much more comfortable with.
link |
01:35:03.120
Like, oh, if you're stressed,
link |
01:35:05.720
then your heart rate might rise
link |
01:35:08.200
and all kinds of sort of toxins might be released
link |
01:35:10.960
and that can have a detrimental effect in your body,
link |
01:35:13.600
et cetera, et cetera, et cetera.
link |
01:35:14.800
So maybe it's easier to understand your body
link |
01:35:18.080
healing from your mind
link |
01:35:20.040
by your mind is not killing your body,
link |
01:35:23.040
or at least it's killing it less.
link |
01:35:24.560
So I think that aspect of the stress equation
link |
01:35:28.000
is a little easier for most of us to conceptualize,
link |
01:35:31.800
but then the healing part is perhaps the same pathways,
link |
01:35:35.160
perhaps different pathways,
link |
01:35:36.160
but again, something that is totally untapped scientifically.
link |
01:35:39.520
I think we try to bring this question up a couple of times,
link |
01:35:42.920
but let's return to it again,
link |
01:35:44.640
is what do you think is the difference
link |
01:35:46.440
between the way a computer represents information,
link |
01:35:49.480
the human genome represents and stores information?
link |
01:35:53.120
And maybe broadly, what is the difference
link |
01:35:55.560
between how you think about computers
link |
01:35:57.840
and how you think about biological systems?
link |
01:36:00.400
So I made a very provocative claim earlier
link |
01:36:02.520
that we are a digital computer.
link |
01:36:04.360
Like I said, at the core lies a digital code
link |
01:36:06.360
and that's true in many ways,
link |
01:36:07.520
but surrounding that digital core,
link |
01:36:09.480
there's a huge amount of analog.
link |
01:36:11.440
If you look at our brain, it's not really digital.
link |
01:36:13.680
If you look at our sort of RNA
link |
01:36:15.760
and all of that stuff inside our cell,
link |
01:36:17.160
it's not really digital.
link |
01:36:18.000
It's really analog in many ways,
link |
01:36:21.000
but let's start with the code
link |
01:36:22.800
and then we'll expand to the rest.
link |
01:36:24.800
So the code itself is digital.
link |
01:36:27.800
So there's genes.
link |
01:36:28.680
You can think of the genes as, I don't know,
link |
01:36:30.840
the procedures, the functions inside your language.
link |
01:36:33.840
And then somehow you have to turn these functions on.
link |
01:36:36.400
How do you call a gene?
link |
01:36:37.320
How do you call that function?
link |
01:36:39.360
The way that you would do it in old programming languages
link |
01:36:41.880
is go to address whatever in your memory
link |
01:36:44.560
and then you'd start running from there.
link |
01:36:46.240
And modern programming languages
link |
01:36:48.920
have encapsulated this into functions
link |
01:36:50.800
and objects and all of that.
link |
01:36:52.000
And it's nice and cute, but in the end, deep down,
link |
01:36:54.560
there's still an assembly code
link |
01:36:55.560
that says go to that instruction
link |
01:36:57.600
and it runs that instruction.
link |
01:36:59.680
If you look at the human genome
link |
01:37:01.600
and the genome of pretty much most species out there,
link |
01:37:06.800
there's no go to function.
link |
01:37:08.160
You just don't start transcribing in position 13,000,
link |
01:37:15.280
13,527 in chromosome 12.
link |
01:37:18.760
You instead have content based indexing.
link |
01:37:21.920
So at every location in the genome,
link |
01:37:25.120
in front of the genes that need to be turned on,
link |
01:37:28.760
I don't know, when you drink coffee,
link |
01:37:30.560
there's a little coffee marker in front of all of them.
link |
01:37:34.440
And whenever your cells that metabolize coffee
link |
01:37:38.480
need to metabolize coffee,
link |
01:37:39.760
they basically see coffee and they're like,
link |
01:37:41.280
ooh, let's go turn on all the coffee marked genes.
link |
01:37:44.720
So there's basically these small motifs,
link |
01:37:48.040
these small sequences that we call regulatory motifs.
link |
01:37:50.840
They're like patterns of DNA.
link |
01:37:52.040
They're only eight characters long or so,
link |
01:37:54.680
like GAT, GCA, et cetera.
link |
01:37:57.920
And these motifs work in combinations
link |
01:38:01.560
and every one of them has some recruitment affinity
link |
01:38:06.320
for a different protein that will then come and bind it
link |
01:38:09.520
and together collections of these motifs
link |
01:38:11.840
create regions that we call regulatory regions
link |
01:38:15.440
that can be either promoters near the beginning of the gene
link |
01:38:19.280
and that basically tells you
link |
01:38:20.160
where the function actually starts, where you call it,
link |
01:38:22.480
and then enhancers that are looping around of the DNA
link |
01:38:26.200
that basically bring the machinery
link |
01:38:28.200
that binds those enhancers
link |
01:38:29.800
and then bring it onto the promoter,
link |
01:38:32.520
which then recruits the right sort of the ribosome
link |
01:38:36.080
and the polymerase and all of that thing,
link |
01:38:37.800
which will first transcribe and then export
link |
01:38:40.560
and then eventually translate in the cytoplasm,
link |
01:38:42.680
you know, whatever RNA molecule.
link |
01:38:45.520
So the beauty of the way
link |
01:38:50.520
that the digital computer that's the genome works
link |
01:38:54.280
is that it's extremely fault tolerant.
link |
01:38:57.960
If I took your hard drive
link |
01:38:59.480
and I messed with 20% of the letters in it,
link |
01:39:03.160
of the zeros and ones and I flipped them,
link |
01:39:05.880
you'd be in trouble.
link |
01:39:07.400
If I take the genome and I flipped 20% of the letters,
link |
01:39:11.400
you probably won't even notice.
link |
01:39:13.880
And that resilience.
link |
01:39:15.320
That's fascinating, yeah.
link |
01:39:16.720
Is a key design principle.
link |
01:39:18.840
And again, I'm anthropomorphizing here,
link |
01:39:20.760
but it's a key driving principle
link |
01:39:22.400
of how biological systems work.
link |
01:39:24.320
They're first resilient and then anything else.
link |
01:39:27.880
And when you look at this incredible beauty of life
link |
01:39:32.160
from the most, I don't know, beautiful,
link |
01:39:35.480
I don't know, human genome maybe of humanity
link |
01:39:38.280
and all of the ideals that should come with it
link |
01:39:40.840
to the most terrifying genome,
link |
01:39:42.360
like, I don't know, COVID 19, SARS COVID 2
link |
01:39:45.520
and the current pandemic,
link |
01:39:47.640
you basically see this elegance
link |
01:39:50.280
as the epitome of clean design,
link |
01:39:54.520
but it's dirty.
link |
01:39:55.920
It's a mess.
link |
01:39:57.280
It's, you know, the way to get there is hugely messy.
link |
01:40:02.200
And that's something that we as computer scientists
link |
01:40:04.400
don't embrace.
link |
01:40:06.120
We like to have clean code.
link |
01:40:08.040
You know, like in engineering,
link |
01:40:10.360
they teach you about compartmentalization,
link |
01:40:12.240
about sort of separating functions,
link |
01:40:13.720
about modularity, about hierarchical design.
link |
01:40:17.080
None of that applies in biology.
link |
01:40:19.040
Testing.
link |
01:40:19.880
Testing, sure.
link |
01:40:22.320
Yeah, biology does plenty of that.
link |
01:40:24.200
But I mean, through evolutionary exploration.
link |
01:40:26.800
But if you look at biological systems,
link |
01:40:31.040
first they are robust
link |
01:40:33.440
and then they specialize to become anything else.
link |
01:40:36.680
And if you look at viruses,
link |
01:40:38.240
the reason why they're so elegant
link |
01:40:41.040
when you look at the design of this, you know, genome,
link |
01:40:44.600
it seems so elegant.
link |
01:40:46.120
And the reason for that is that it's been stripped down
link |
01:40:49.680
from something much larger
link |
01:40:51.600
because of the pressure to keep it compact.
link |
01:40:53.960
So many compact genomes out there
link |
01:40:56.040
have ancestors that were much larger.
link |
01:40:58.680
You don't start small and become big.
link |
01:41:00.760
You go through a loop of add a bunch of stuff,
link |
01:41:03.640
increase complexity, and then, you know, slim it down.
link |
01:41:07.240
And one of my early papers was in fact on genome duplication.
link |
01:41:12.120
One of the things we found is that baker's yeast,
link |
01:41:14.080
which is the, you know, yeast that you use to make bread,
link |
01:41:17.600
but also the yeast that you use to make wine,
link |
01:41:19.480
which is basically the dominant species
link |
01:41:20.960
when you go in the fields of Tuscany
link |
01:41:22.360
and you say, you know, what's out there,
link |
01:41:24.040
it's basically saccharomyces cerevisiae,
link |
01:41:26.320
or the way my Italian friends say,
link |
01:41:27.880
saccharomyces cerevisiae.
link |
01:41:30.120
So, so.
link |
01:41:33.000
Oh, which means what?
link |
01:41:34.480
Oh, saccharomyces, okay, I'm sorry, I'm Greek.
link |
01:41:36.680
So yeah, zacharo, mikis, zacharo is sugar,
link |
01:41:39.680
mikis is fungus.
link |
01:41:41.120
Yes, cerevisiae, cerveza, beer.
link |
01:41:44.520
So it means the sugar fungus of beer.
link |
01:41:47.200
Yeah.
link |
01:41:48.040
You know, less, less sounding to the ear.
link |
01:41:51.080
Still poetic, yeah.
link |
01:41:52.840
So anyway, saccharomyces cerevisiae,
link |
01:41:54.960
basically the major baker's yeast out there
link |
01:41:57.040
is the descendant of a whole genome duplication.
link |
01:42:00.440
Why would a whole gene duplication even happen?
link |
01:42:02.880
When it happened is coinciding
link |
01:42:06.080
with about a hundred million years ago
link |
01:42:08.240
and the emergence of fruit bearing plants.
link |
01:42:14.320
Why fruit bearing plants?
link |
01:42:15.560
Because animals would eat the fruit
link |
01:42:19.040
and would walk around and poop huge amounts of nutrients
link |
01:42:23.640
along with a seed for the plants to spread.
link |
01:42:26.480
Before that, plants were not spreading through animals,
link |
01:42:29.000
they were spreading through wind
link |
01:42:30.480
and all kinds of other ways.
link |
01:42:32.360
But basically the moment you have fruit bearing plants,
link |
01:42:34.720
these plants are basically creating this abundance
link |
01:42:38.760
of sugar in the environment.
link |
01:42:40.240
So there's an evolutionary niche that gets created.
link |
01:42:42.920
And in that evolutionary niche,
link |
01:42:44.080
you basically have enough sugar
link |
01:42:46.640
that a whole genome duplication,
link |
01:42:48.680
which initially is a very messy event,
link |
01:42:51.040
allows you to then, you know,
link |
01:42:53.760
relieve some of that complexity.
link |
01:42:56.000
So I had to pause, what does genome duplication mean?
link |
01:42:59.520
That basically means that instead of having eight chromosomes,
link |
01:43:03.200
you can now have 16 chromosomes.
link |
01:43:06.240
So, but the duplication at first,
link |
01:43:09.600
when you go to 16, you're not using that.
link |
01:43:13.760
Oh yeah, you are.
link |
01:43:15.120
Yeah, so basically from one day to the next,
link |
01:43:17.280
you went from having eight chromosomes
link |
01:43:18.600
to having 16 chromosomes.
link |
01:43:20.280
Probably a non disjunction event during a duplication,
link |
01:43:22.920
during a division.
link |
01:43:24.160
So you basically divide the cell
link |
01:43:25.800
instead of half the genome going this way
link |
01:43:27.760
and half the genome going the other way
link |
01:43:29.000
after duplication of the genome,
link |
01:43:30.640
you basically have all of it going to one cell
link |
01:43:33.000
and then there's sufficient messiness there
link |
01:43:35.840
that you end up with slight differences
link |
01:43:38.320
that make most of these chromosomes
link |
01:43:39.760
be actually preserved.
link |
01:43:42.280
It's a long story short to me.
link |
01:43:43.120
But that's a big upgrade, right?
link |
01:43:45.000
So that's...
link |
01:43:45.840
Not necessarily,
link |
01:43:46.760
because what happens immediately thereafter
link |
01:43:48.480
is that you start massively losing
link |
01:43:50.320
tons of those duplicated genes.
link |
01:43:52.280
So 90% of those genes were actually lost
link |
01:43:55.360
very rapidly after whole gene duplication.
link |
01:43:58.160
And the reason for that is that biology is not intelligent,
link |
01:44:01.680
it's just ruthless selection, random mutation.
link |
01:44:06.480
So the ruthless selection basically means
link |
01:44:08.520
that as soon as one of the random mutations hit one gene,
link |
01:44:11.400
ruthless selection just kills off that gene.
link |
01:44:13.360
It's just,
link |
01:44:16.680
if you have a pressure to maintain a small compact genome,
link |
01:44:19.520
you will very rapidly lose the second copy
link |
01:44:21.680
of most of your genes and a small number 10%
link |
01:44:24.240
were kept in two copies.
link |
01:44:25.720
And those had to do a lot with environment adaptation,
link |
01:44:28.800
with the speed of replication,
link |
01:44:31.080
with the speed of translation and with sugar processing.
link |
01:44:34.240
So I'm making a long story short
link |
01:44:36.000
to basically say that evolution is messy.
link |
01:44:38.720
The only way...
link |
01:44:39.960
Like, so the example that I was giving
link |
01:44:42.160
of messing with 20% of your bits in your computer,
link |
01:44:45.840
totally bogus.
link |
01:44:47.200
Duplicating all your functions
link |
01:44:48.720
and just throwing them out there in the same function,
link |
01:44:51.880
just totally bogus.
link |
01:44:52.840
Like this would never work in an engineer system.
link |
01:44:55.200
But biological systems,
link |
01:44:56.960
because of this content based indexing
link |
01:44:59.080
and because of this modularity that comes
link |
01:45:01.880
from the fact that the gene is controlled
link |
01:45:04.200
by a series of tags.
link |
01:45:05.200
And now if you need this gene in another setting,
link |
01:45:08.160
you just add some more tags
link |
01:45:09.760
that will basically turn it on also in those settings.
link |
01:45:12.560
So this gene is now pressured to do two different functions
link |
01:45:17.280
and it builds up complexity.
link |
01:45:19.760
I see a whole gene duplication
link |
01:45:21.240
and gene duplication in general
link |
01:45:22.560
as a way to relieve that complexity.
link |
01:45:24.560
So you have this gradual buildup of complexity
link |
01:45:26.640
as functions get sort of added onto the existing genes.
link |
01:45:30.920
And then boom, you duplicate your workforce.
link |
01:45:34.160
And you now have two copies of this gene.
link |
01:45:36.720
One will probably specialize to do one
link |
01:45:38.760
and the other one will specialize to do the other
link |
01:45:40.440
or one will maintain the ancestral function.
link |
01:45:42.160
The other one will sort of be free to evolve
link |
01:45:44.800
and specialize while losing the ancestral function
link |
01:45:47.720
and so on and so forth.
link |
01:45:48.640
So that's how genomes evolve.
link |
01:45:49.960
They're just messy things,
link |
01:45:52.040
but they're extremely fault tolerant
link |
01:45:54.600
and they're extremely able to deal with mutations
link |
01:45:58.400
because that's the very way that you generate new functions.
link |
01:46:03.800
So new functionalization comes
link |
01:46:05.440
from the very thing that breaks it.
link |
01:46:07.720
So even in the current pandemic,
link |
01:46:09.120
many people are asking me which mutations matter the most.
link |
01:46:12.560
And what I tell them is,
link |
01:46:13.800
well, we can study the evolutionary dynamics
link |
01:46:16.240
of the current genome to then understand
link |
01:46:19.520
which mutations have previously happened or not.
link |
01:46:23.120
And which mutations happen in genes
link |
01:46:26.040
that evolve rapidly or not.
link |
01:46:28.040
And one of the things we found, for example,
link |
01:46:29.720
is that the genes that evolved rapidly in the past
link |
01:46:33.840
are still evolving rapidly now in the current pandemic.
link |
01:46:36.720
The genes that evolved slowly in the past
link |
01:46:38.680
are still evolving slowly.
link |
01:46:40.040
Which means that they're useful?
link |
01:46:41.720
Which means that they're under
link |
01:46:43.360
the same evolutionary pressures.
link |
01:46:45.280
But then the question is what happens in specific mutations?
link |
01:46:49.440
So if you look at the D614 gene mutations,
link |
01:46:52.560
that's been all over the news.
link |
01:46:53.840
So in position 614, in the amino acids 614 of the S protein,
link |
01:46:59.720
there's a D2 gene mutation
link |
01:47:02.120
that sort of has creeped over the population.
link |
01:47:07.040
That mutation, we found out through my work,
link |
01:47:10.040
disrupts a perfectly conserved nucleotide position
link |
01:47:13.480
that has never been changed in the history
link |
01:47:15.800
of millions of years of equivalent
link |
01:47:17.920
per million evolution of these viruses.
link |
01:47:23.080
That basically means that it's a completely new adaptation
link |
01:47:25.960
to human.
link |
01:47:27.480
And that mutation has now gone from 1% frequency
link |
01:47:30.840
to 90% frequency in almost all outbreaks.
link |
01:47:33.800
So this mutation, I like how you say the 416,
link |
01:47:38.880
what was it, okay.
link |
01:47:39.720
Yeah, 614, sorry.
link |
01:47:40.640
614.
link |
01:47:41.480
D614G.
link |
01:47:43.200
D614, so literally, so what you're saying
link |
01:47:46.560
is this is like a chess move.
link |
01:47:48.440
So it just mutated one letter to another.
link |
01:47:50.560
Exactly.
link |
01:47:51.400
And that hasn't happened before.
link |
01:47:53.000
Yeah, never.
link |
01:47:54.320
And this somehow, this mutation is really useful.
link |
01:47:58.120
It's really useful in the current environment of the genome,
link |
01:48:02.000
which is moving from human to human.
link |
01:48:04.920
When it was moving from bat to bat,
link |
01:48:06.840
it couldn't care less for that mutation,
link |
01:48:08.680
but it's environment specific.
link |
01:48:09.960
So now that it's moving from human to human,
link |
01:48:12.560
it's moving way better, like by orders of magnitude.
link |
01:48:15.920
What do you, okay, so you're like tracking
link |
01:48:18.440
this evolutionary dynamics, which is fascinating,
link |
01:48:22.520
but what do you do with that?
link |
01:48:24.200
So what does that mean?
link |
01:48:25.320
What does this mean, what do you make,
link |
01:48:27.560
what do you make of this mutation
link |
01:48:29.120
in trying to anticipate, I guess,
link |
01:48:31.560
is one of the things you're trying to do
link |
01:48:34.120
is anticipate where, how this unrolls into the future,
link |
01:48:37.840
this evolutionary dynamics.
link |
01:48:39.760
Such a great question.
link |
01:48:40.640
So there's two things.
link |
01:48:42.880
Remember when I was saying earlier,
link |
01:48:44.680
mutation is the path to new things,
link |
01:48:47.040
but also the path to break old things.
link |
01:48:49.720
So what we know is that this position
link |
01:48:52.960
was extremely preserved through gazillions of mutations.
link |
01:48:56.600
That mutation was never tolerated
link |
01:48:58.440
when it was moving from bats to bats.
link |
01:49:00.200
So that basically means that that position
link |
01:49:02.480
is extremely important in the function of that protein.
link |
01:49:05.600
That's the first thing it tells.
link |
01:49:06.920
The second one is that that position
link |
01:49:09.280
was very well suited to bat transmission,
link |
01:49:12.360
but now is not well suited to human transmission,
link |
01:49:14.720
so it got rid of it.
link |
01:49:15.840
And it now has a new version of that amino acid
link |
01:49:18.840
that basically makes it much easier
link |
01:49:20.920
to transmit from human to human.
link |
01:49:22.720
So in terms of the evolutionary history
link |
01:49:27.440
teaching us about the future,
link |
01:49:29.800
it basically tells us here's the regions
link |
01:49:31.960
that are currently mutating.
link |
01:49:34.760
Here's the regions that are most likely
link |
01:49:36.400
to mutate going forward.
link |
01:49:37.880
As you're building a vaccine,
link |
01:49:39.440
here's what you should be focusing on
link |
01:49:41.680
in terms of the most stable regions
link |
01:49:43.520
that are the least likely to mutate.
link |
01:49:45.440
Or here's the newly evolved functions
link |
01:49:48.200
that are the most likely to be important
link |
01:49:50.240
because they've overcome this local maximum
link |
01:49:54.560
that it had reached in the bat transmission.
link |
01:49:59.360
So anyway, it's a tangent to basically say
link |
01:50:01.760
that evolution works in messy ways.
link |
01:50:04.080
And the thing that you would break
link |
01:50:07.400
is the thing that actually allows you
link |
01:50:10.320
to first go through a lull
link |
01:50:12.160
and then reaching new local maximum.
link |
01:50:15.200
And I often like to say that if engineers
link |
01:50:18.920
had basically designed evolution,
link |
01:50:21.200
we would still be perfectly replicating bacteria
link |
01:50:26.640
because it's my making the bacterium worse
link |
01:50:29.400
that you allow evolution to reach a new optimum.
link |
01:50:32.200
That's, just to pause on that,
link |
01:50:34.520
that's so profound.
link |
01:50:35.840
That's so profound for the entirety
link |
01:50:39.400
of this scientific and engineering disciplines.
link |
01:50:44.680
Exactly.
link |
01:50:45.520
We as engineers need to embrace breaking things.
link |
01:50:48.520
We as engineers need to embrace robustness
link |
01:50:50.960
as the first principle beyond perfection
link |
01:50:54.240
because nothing's gonna ever be perfect.
link |
01:50:56.040
And when you're sending a satellite to Mars,
link |
01:50:58.440
when something goes wrong, it'll break down.
link |
01:51:01.160
As opposed to building systems that tolerate failure
link |
01:51:04.600
and are resilient to that.
link |
01:51:08.840
And in fact, get better through that.
link |
01:51:11.080
So the SpaceX approach versus NASA for the...
link |
01:51:14.400
For example.
link |
01:51:16.200
Is there something we can learn about the incredible,
link |
01:51:21.320
take lessons from the incredible biological systems
link |
01:51:23.960
in their resilience, in the mushiness, the messiness
link |
01:51:27.600
to our computing systems, to our computers?
link |
01:51:31.880
It would basically be starting from scratch in many ways.
link |
01:51:35.280
It would basically be building new paradigms
link |
01:51:38.960
that don't try to get the right answer all the time,
link |
01:51:42.760
but try to get the right answer most of the time
link |
01:51:45.600
or a lot of the time.
link |
01:51:47.000
Do you see deep learning systems in the whole world
link |
01:51:49.280
of machine learning as kind of taking a step
link |
01:51:51.120
in that direction?
link |
01:51:52.000
Absolutely, absolutely.
link |
01:51:53.600
Basically by allowing this much more natural evolution
link |
01:51:57.560
of these parameters, you basically...
link |
01:52:01.080
And if you look at sort of deep learning systems again,
link |
01:52:04.000
they're not inspired by the genome aspect of biology,
link |
01:52:07.440
they're inspired by the brain aspect of biology.
link |
01:52:10.160
And again, I want you to pause for a second
link |
01:52:12.560
and realize the complexity of the entire human brain
link |
01:52:18.720
with trillions of connections within our neurons,
link |
01:52:22.760
with millions of cells talking to each other,
link |
01:52:26.640
is still encoded within that same genome.
link |
01:52:29.040
That same genome encodes every single freaking cell type
link |
01:52:36.080
of the entire body.
link |
01:52:37.920
Every single cell is encoded by the same code.
link |
01:52:41.040
And yet specialization allows you to have
link |
01:52:45.240
the single viral like genome that self replicates,
link |
01:52:50.040
the single module, modular automaton,
link |
01:52:54.200
work with other copies of itself, it's mind boggling.
link |
01:52:57.360
Create complex organs through which blood flows.
link |
01:53:01.600
And what is that blood?
link |
01:53:02.680
The same freaking genome.
link |
01:53:05.560
Create organs that communicate with each other.
link |
01:53:09.840
And what are these organs?
link |
01:53:11.080
The exact same genome.
link |
01:53:13.120
Create a brain that is innervated by massive amounts
link |
01:53:17.560
of blood pumping energy to it,
link |
01:53:21.240
20% of our energetic needs to the brain from the same genome.
link |
01:53:28.240
And all of the neuronal connections,
link |
01:53:30.120
all of the auxiliary cells, all of the immune cells,
link |
01:53:33.920
the astrocytes, the ligodendrocytes, the neurons,
link |
01:53:35.920
the excitatory, the inhibitory neurons,
link |
01:53:37.360
all of the different classes of parasites,
link |
01:53:39.480
the blood brain barrier, all of that, same genome.
link |
01:53:42.880
One way to see that in a sad, this one is beautiful.
link |
01:53:47.680
The sad thing is thinking about the trillions
link |
01:53:50.800
of organisms that died to create that.
link |
01:53:55.240
You mean on the evolutionary path to humans?
link |
01:53:57.080
On the evolutionary path to humans.
link |
01:53:59.600
It's crazy, there's two descendant of apes
link |
01:54:02.680
just talking on a podcast.
link |
01:54:04.760
Okay, it's just so mind boggling.
link |
01:54:08.520
Just to boggle our minds a little bit more.
link |
01:54:11.120
Us talking to each other,
link |
01:54:13.920
we are basically generating a series of vocal utterances
link |
01:54:18.440
through our pulsating of vocal cords received through this.
link |
01:54:23.440
The people who listen to this
link |
01:54:26.160
are taking a completely different path
link |
01:54:29.240
to that information transfer, yet through language.
link |
01:54:32.880
But imagine if we could connect these brains
link |
01:54:36.160
directly to each other.
link |
01:54:38.920
The amount of information that I'm condensing
link |
01:54:41.600
into a small number of words is a huge funnel,
link |
01:54:46.360
which then you receive and you expand
link |
01:54:49.480
into a huge number of thoughts from that small funnel.
link |
01:54:55.760
In many ways, engineers would love
link |
01:54:58.080
to have the whole information transfer,
link |
01:54:59.880
just take the whole set of neurons and throw them away.
link |
01:55:02.640
I mean, throw them to the other person.
link |
01:55:05.440
This might actually not be better
link |
01:55:07.280
because in your misinterpretation
link |
01:55:10.640
of every word that I'm saying,
link |
01:55:13.000
you are creating new interpretation
link |
01:55:14.680
that might actually be way better
link |
01:55:16.080
than what I meant in the first place.
link |
01:55:17.920
The ambiguity of language perhaps
link |
01:55:21.760
might be the secret to creativity.
link |
01:55:25.000
Every single time you work on a project by yourself,
link |
01:55:28.400
you only bounce ideas with one person
link |
01:55:31.120
and your neurons are basically fully cognizant
link |
01:55:33.760
of what these ideas are.
link |
01:55:35.880
But the moment you interact with another person,
link |
01:55:37.720
the misinterpretations that happen
link |
01:55:41.080
might be the most creative part of the process.
link |
01:55:43.760
With my students, every time we have a research meeting,
link |
01:55:45.600
I very often pause and say,
link |
01:55:47.560
let me repeat what you just said in a different way.
link |
01:55:50.400
And I sort of go on and brainstorm
link |
01:55:52.400
with what they were saying,
link |
01:55:53.680
but by the third time,
link |
01:55:55.960
it's not what they were saying at all.
link |
01:55:58.000
And when they pick up what I'm saying,
link |
01:55:59.480
they're like, oh, well, dah, dah, dah.
link |
01:56:01.160
Now they've sort of learned something very different
link |
01:56:04.160
from what I was saying.
link |
01:56:05.000
And that is the same kind of messiness
link |
01:56:08.480
that I'm describing in the genome itself.
link |
01:56:10.960
It's sort of embracing the messiness.
link |
01:56:13.600
And that's a feature, not a book.
link |
01:56:15.400
Exactly.
link |
01:56:16.240
And in the same way, when you're thinking
link |
01:56:17.560
about sort of these deep learning systems
link |
01:56:19.960
that will allow us to sort of be more creative perhaps
link |
01:56:23.600
or learn better approximations of these complex functions,
link |
01:56:27.560
again, tuned to the universe that we inhabit,
link |
01:56:30.720
you have to embrace the breaking.
link |
01:56:33.680
You have to embrace the,
link |
01:56:35.400
how do we get out of these local optima?
link |
01:56:38.000
And a lot of the design paradigms
link |
01:56:40.960
that have made deep learning so successful
link |
01:56:43.400
are ways to get away from that,
link |
01:56:45.400
ways to get better training
link |
01:56:47.360
by sort of sending long range messages,
link |
01:56:50.520
these LSTM models and the sort of feed forward loops
link |
01:56:55.920
that sort of jump through layers
link |
01:56:59.280
of a convolutional neural network.
link |
01:57:00.920
All of these things are basically ways to push you out
link |
01:57:04.960
of these local maxima.
link |
01:57:07.360
And that's sort of what evolution does.
link |
01:57:08.840
That's what language does.
link |
01:57:09.840
That's what conversation and brainstorming does.
link |
01:57:12.360
That's what our brain does.
link |
01:57:14.120
So this design paradigm is something that's pervasive
link |
01:57:18.320
and yet not taught in schools,
link |
01:57:20.560
not taught in engineering schools
link |
01:57:22.280
where everything's minutely modularized
link |
01:57:24.520
to make sure that we never deviate
link |
01:57:26.040
from whatever signal we're trying to emit
link |
01:57:28.640
as opposed to let all hell breaks loose
link |
01:57:31.440
because that's the path to paradise.
link |
01:57:34.000
The path to paradise.
link |
01:57:35.440
Yeah, I mean, it's difficult to know how to teach that
link |
01:57:38.040
and what to do with it.
link |
01:57:39.320
I mean, it's difficult to know how to build up
link |
01:57:43.680
the scientific method around messiness.
link |
01:57:46.640
I mean, it's not all messiness.
link |
01:57:49.960
We need some cleanness.
link |
01:57:51.960
And going back to the example with Mars,
link |
01:57:54.400
that's probably the place where I want
link |
01:57:55.520
to sort of moderate error as much as possible
link |
01:57:58.800
and sort of control the environment as much as possible.
link |
01:58:01.080
But if you're trying to repopulate Mars,
link |
01:58:03.160
well, maybe messiness is a good thing then.
link |
01:58:05.320
On that, you quickly mentioned this
link |
01:58:09.280
in terms of us using our vocal cords
link |
01:58:12.920
to speak on a podcast.
link |
01:58:15.120
So Elon Musk and Neuralink are working
link |
01:58:17.800
on trying to plug, as per our discussion
link |
01:58:22.680
with computers and biological systems,
link |
01:58:24.920
to connect the two.
link |
01:58:25.840
He's trying to connect our brain to a computer
link |
01:58:30.640
to create a brain computer interface
link |
01:58:32.840
where they can communicate back and forth.
link |
01:58:36.160
On this line of thinking, do you think this is possible
link |
01:58:40.960
to bridge the gap between our engineered computing systems
link |
01:58:45.200
and the messy biological systems?
link |
01:58:49.280
My answer would be absolutely.
link |
01:58:51.920
You know, there's no doubt that we can understand
link |
01:58:54.440
more and more about what goes on in the brain
link |
01:58:57.120
and we can sort of train the brain.
link |
01:59:00.520
I don't know if you remember the Palm Pilot.
link |
01:59:03.600
Yeah, Palm Pilot, yeah.
link |
01:59:04.720
Remember this whole sort of alphabet that they had created?
link |
01:59:08.440
Am I thinking of the same thing?
link |
01:59:10.920
It's basically, you had a little pen
link |
01:59:13.280
and for every character, you had a little scribble
link |
01:59:17.000
that was unique that the machine could understand.
link |
01:59:19.800
And that instead of trying the machine
link |
01:59:22.520
and trying to teach the machine
link |
01:59:23.640
to recognize human characters,
link |
01:59:25.200
you had basically, they figured out
link |
01:59:27.200
that it's better and easier to train humans
link |
01:59:29.960
to create human like characters
link |
01:59:31.840
that the machine is better at recognizing.
link |
01:59:34.760
So in the same way, I think what will happen
link |
01:59:38.320
is that humans will be trained
link |
01:59:40.600
to be able to create the mind pattern
link |
01:59:43.200
that the machine will respond to
link |
01:59:45.160
before the machine truly comprehends our thoughts.
link |
01:59:47.760
So the first human brain interfaces
link |
01:59:50.160
will be tricking humans to speak the machine language
link |
01:59:53.640
where with the right set of electrodes,
link |
01:59:55.640
I can sort of trick my brain into doing this.
link |
01:59:57.640
And this is the same way that many people teach,
link |
02:00:00.240
like learn to control artificial limbs.
link |
02:00:02.960
You basically try a bunch of stuff
link |
02:00:04.520
and eventually you figure out how your limbs work.
link |
02:00:06.880
That might not be very different
link |
02:00:08.200
from how humans learn to use their natural limbs
link |
02:00:11.480
when they first grow up.
link |
02:00:13.080
Basically, you have these, you know,
link |
02:00:14.920
neoteny period of, you know,
link |
02:00:17.960
this puddle of soup inside your brain,
link |
02:00:21.320
trying to figure out how to even make neural connections
link |
02:00:23.840
before you're born and then learning sounds
link |
02:00:27.280
in utero of, you know, all kinds of echoes
link |
02:00:31.480
and, you know, eventually getting out in the real world.
link |
02:00:35.840
And I don't know if you've seen newborns,
link |
02:00:37.280
but they just stare around a lot.
link |
02:00:39.840
You know, one way to think about this
link |
02:00:41.680
as a machine learning person is,
link |
02:00:43.000
oh, they're just training their edge detectors.
link |
02:00:46.080
And eventually they figure out
link |
02:00:47.320
how to train their edge detectors.
link |
02:00:48.680
They work through the second layer of the visual cortex
link |
02:00:50.800
and the third layer and so on and so forth.
link |
02:00:52.640
And you basically have this learning
link |
02:00:58.320
how to control your limbs
link |
02:00:59.360
that probably comes at the same time.
link |
02:01:01.000
You're sort of, you know, throwing random things there
link |
02:01:03.280
and you realize that, oh, wow,
link |
02:01:04.720
when I do this thing, my limb moves.
link |
02:01:08.200
Let's do the following experiment.
link |
02:01:09.240
Take a breath.
link |
02:01:11.880
What muscles did you flex?
link |
02:01:13.480
Now take another breath and think what muscles do I flex?
link |
02:01:16.600
The first thing that you're thinking
link |
02:01:17.920
when you're taking a breath
link |
02:01:19.840
is the impact that it has on your lungs.
link |
02:01:22.320
You're like, oh, I'm now gonna increase my lungs
link |
02:01:24.080
or I'm not gonna bring air in.
link |
02:01:25.440
But what you're actually doing
link |
02:01:26.360
is just changing your diaphragm.
link |
02:01:29.160
That's not conscious, of course.
link |
02:01:31.880
You never think of the diaphragm as a thing.
link |
02:01:34.920
And why is that?
link |
02:01:36.000
That's probably the same reason
link |
02:01:37.360
why I think of moving my finger
link |
02:01:38.800
when I actually move my finger.
link |
02:01:40.520
I think of the effect instead of actually thinking
link |
02:01:42.520
of whatever muscle is twitching
link |
02:01:44.080
that actually causes my finger to move.
link |
02:01:46.440
So we basically in our first years of life
link |
02:01:49.240
build up this massive lookup table
link |
02:01:52.360
between whatever neuronal firing we do
link |
02:01:55.400
and whatever action happens in our body that we control.
link |
02:02:00.880
If you have a kid grow up with a third limb,
link |
02:02:04.280
I'm sure they'll figure out how to control them
link |
02:02:06.600
probably at the same rate as their natural limbs.
link |
02:02:09.440
And a lot of the work would be done by the...
link |
02:02:13.320
If a third limb is a computer,
link |
02:02:15.520
you kind of have a, not a faith, but a thought
link |
02:02:20.440
that the brain might be able to figure out...
link |
02:02:24.360
The plasticity would come from the brain.
link |
02:02:26.840
The brain would be cleverer than the machine at first.
link |
02:02:28.960
When I talk about a third limb,
link |
02:02:29.960
that's exactly what I'm saying, an artificial limb
link |
02:02:32.240
that basically just controls your mouse while you're typing.
link |
02:02:35.640
Perfectly natural thing.
link |
02:02:36.600
I mean, again, in a few hundred years.
link |
02:02:40.320
Maybe sooner than that.
link |
02:02:41.600
But basically, as long as the machine is consistent
link |
02:02:46.040
in the way that it will respond to your brain impulses,
link |
02:02:49.760
you'll figure out how to control that
link |
02:02:51.680
and you could play tennis with your third limb.
link |
02:02:53.920
And let me go back to consistency.
link |
02:02:57.480
People who have dramatic accidents
link |
02:03:01.280
that basically take out a whole chunk of their brain
link |
02:03:03.920
can be taught to coopt other parts of the brain
link |
02:03:07.000
to then control that part.
link |
02:03:08.560
You can basically build up that tissue again
link |
02:03:10.840
and eventually train your body how to walk again
link |
02:03:13.480
and how to read again and how to play again
link |
02:03:15.400
and how to think again, how to speak a language again,
link |
02:03:17.160
et cetera.
link |
02:03:18.080
So there's a massive amount of malleability
link |
02:03:21.280
that happens naturally in our way of controlling our body,
link |
02:03:26.600
our brain, our thoughts, our vocal cords, our limbs,
link |
02:03:29.720
et cetera.
link |
02:03:30.760
And human machine interfaces are inevitable
link |
02:03:35.640
if we sort of figure out how to read these electric impulses,
link |
02:03:39.240
but the resolution at which we can understand human thought
link |
02:03:43.400
right now is nil, is ridiculous.
link |
02:03:46.560
So how are human thoughts encoded?
link |
02:03:49.120
It's basically combinations of neurons that cofire
link |
02:03:53.560
and these create these things called engrams
link |
02:03:55.720
that eventually form memories and so on and so forth.
link |
02:03:58.920
We know nothing of all that stuff.
link |
02:04:01.920
So before we can actually read into your brain
link |
02:04:05.600
that you wanna build a program
link |
02:04:06.680
that does this and this and this and that,
link |
02:04:08.920
we need a lot of neuroscience.
link |
02:04:10.960
Well, so to push back on that,
link |
02:04:13.480
do you think it's possible that without understanding
link |
02:04:16.680
the functionally about the brain or from the neuroscience
link |
02:04:20.000
or the cognitive science or psychology,
link |
02:04:22.080
whichever level of the brain we'll look at,
link |
02:04:24.220
do you think if we just connect them,
link |
02:04:26.700
just like per your previous point,
link |
02:04:29.200
if we just have a high enough resolution
link |
02:04:30.840
between connection between a Wikipedia and your brain,
link |
02:04:34.400
the brain will just figure it out with us understanding
link |
02:04:38.160
because that's one of the innovations of Neuralink
link |
02:04:40.320
is they're increasing the number of connections
link |
02:04:43.540
to the brain to like several thousand,
link |
02:04:45.320
which before was in the dozens or whatever.
link |
02:04:48.280
You're still off by a few orders of magnitude
link |
02:04:51.000
on the order of seven.
link |
02:04:52.160
Right, but the thing is, the hope is if you increase
link |
02:04:57.480
that number more and more and more,
link |
02:04:58.800
maybe you don't need to understand anything
link |
02:05:00.600
about the actual how human thought
link |
02:05:03.780
is represented in the brain.
link |
02:05:04.960
You can just let it figure it out by itself.
link |
02:05:08.520
Keanu Reeves waking up and saying, I know cook food.
link |
02:05:10.680
Yeah, exactly.
link |
02:05:13.160
So yeah, sure.
link |
02:05:14.600
You don't have faith in the plasticity of the brain
link |
02:05:16.720
to that degree.
link |
02:05:18.240
It's not about brain plasticity.
link |
02:05:19.840
It's about the input aspect.
link |
02:05:21.880
Basically, I think on the output aspect,
link |
02:05:23.720
being able to control a machine is something
link |
02:05:25.440
that you can probably train your neural impulses
link |
02:05:28.440
that you're sending out to sort of match
link |
02:05:30.940
whatever response you see in the environment.
link |
02:05:33.280
If this thing moved every single time I thought
link |
02:05:35.600
a particular thought, then I could figure out,
link |
02:05:37.340
I could hack my way into moving this thing
link |
02:05:39.520
with just a series of thoughts.
link |
02:05:40.960
I could think guitar, piano, tennis ball,
link |
02:05:45.880
and then this thing would be moving.
link |
02:05:47.120
And then I would just have the series of thoughts
link |
02:05:50.640
that would sort of result in the impulses
link |
02:05:52.640
that will move this thing the way that I want it.
link |
02:05:54.040
And then eventually it'll become natural
link |
02:05:55.560
because I won't even think about it.
link |
02:05:57.640
I mean, in the same way that we control our limbs
link |
02:05:59.120
in a very natural way, but babies don't do that.
link |
02:06:01.360
Babies have to figure it out.
link |
02:06:03.160
And some of that is hard coded,
link |
02:06:04.840
but some of that is actually learned
link |
02:06:06.800
based on whatever soup of neurons you ended up with,
link |
02:06:10.320
whatever connections you pruned them to,
link |
02:06:13.440
and eventually you were born with.
link |
02:06:15.360
A lot of that is coded in the genome,
link |
02:06:17.740
but a huge chunk of that is stochastic.
link |
02:06:19.680
And sort of the way that you sort of create
link |
02:06:21.320
all these neurons, they migrate, they form connections,
link |
02:06:23.440
they sort of spread out,
link |
02:06:25.140
they have particular branching patterns,
link |
02:06:26.520
but then the connectivity itself,
link |
02:06:28.200
unique in every single new person.
link |
02:06:30.120
All this to say that on the output side,
link |
02:06:34.000
absolutely, I'm very, very, you know,
link |
02:06:36.920
hopeful that we can have machines
link |
02:06:38.640
that read thousands of these neuronal connections
link |
02:06:41.920
on the output side, but on the input side, oh boy.
link |
02:06:47.960
I don't expect any time in the near future
link |
02:06:51.240
we'll be able to sort of send a series of impulses
link |
02:06:53.400
that will tell me, oh, earth to sun distance,
link |
02:06:56.280
7.5 million, et cetera, et cetera.
link |
02:06:58.960
Like nowhere.
link |
02:07:00.720
I mean, I think language will still be the input way
link |
02:07:04.480
rather than sort of any kind of more complex.
link |
02:07:07.360
It's a really interesting notion
link |
02:07:08.760
that the ambiguity of language is a feature.
link |
02:07:12.600
And we evolved for millions of years
link |
02:07:16.520
to take advantage of that ambiguity.
link |
02:07:19.520
Exactly.
link |
02:07:20.520
And yet no one teaches us the subtle differences
link |
02:07:23.380
between words that are near cognates,
link |
02:07:26.080
and yet evoke so much more than, you know,
link |
02:07:29.320
one from the other.
link |
02:07:30.760
And yet, you know, when you're choosing words
link |
02:07:34.520
from a list of 20 synonyms,
link |
02:07:36.840
you know exactly the connotation
link |
02:07:38.400
of every single one of them.
link |
02:07:40.040
And that's something that, you know, is there.
link |
02:07:42.600
So yes, there's ambiguity,
link |
02:07:45.120
but there's all kinds of connotations.
link |
02:07:46.800
And in the way that we select our words,
link |
02:07:48.880
we have so much baggage that we're sending along,
link |
02:07:51.320
the way that we're emoting,
link |
02:07:52.960
the way that we're moving our hands
link |
02:07:54.720
every single time we speak,
link |
02:07:56.080
the, you know, the pauses, the eye contact, et cetera.
link |
02:07:58.880
So much higher baud rate than just a vocal,
link |
02:08:01.800
you know, string of characters.
link |
02:08:04.040
Well, let me just take a small tangent on that.
link |
02:08:07.120
Oh, tangent?
link |
02:08:07.960
We haven't done that yet.
link |
02:08:08.800
It's a good idea.
link |
02:08:09.640
Let's do a tangent.
link |
02:08:10.480
We'll return to the origin of life after.
link |
02:08:16.200
So, I mean, you're Greek,
link |
02:08:17.840
but I'm going on this personal journey.
link |
02:08:20.880
I'm going to Paris for the explicit purpose
link |
02:08:25.120
of talking to one of the most famous,
link |
02:08:29.360
a couple who's a famous translators of Russian literature,
link |
02:08:33.200
Dostoevsky, Tolstoy, and they go,
link |
02:08:36.280
that's their art is the translation.
link |
02:08:38.440
And everything I've learned about the translation art,
link |
02:08:44.320
it makes me feel,
link |
02:08:46.120
it's so profound in a way that's so much more profound
link |
02:08:53.240
than the natural language processing papers
link |
02:08:55.400
I read in the machine learning community,
link |
02:08:57.440
that there's such depth to language
link |
02:09:00.440
that I don't know what to do with.
link |
02:09:03.160
I don't know if you've experienced that in your own life
link |
02:09:05.720
with knowing multiple languages.
link |
02:09:08.760
I don't know what to,
link |
02:09:09.840
I don't know how to make sense of it,
link |
02:09:11.680
but there's so much loss in translation
link |
02:09:13.600
between Russian and English,
link |
02:09:15.320
and getting a sense of that.
link |
02:09:17.440
Like, for example,
link |
02:09:19.640
there's like just taking a single sentence
link |
02:09:22.000
from Dostoevsky, and like, there's a lot of them.
link |
02:09:25.440
You could talk for hours
link |
02:09:27.160
about how to translate that sentence properly.
link |
02:09:30.120
That captures the meaning, the period,
link |
02:09:34.360
the culture, the humor, the wit,
link |
02:09:36.560
the suffering that was in the context of the time,
link |
02:09:39.760
all of that could be a single sentence.
link |
02:09:42.280
You could talk forever about what it takes
link |
02:09:46.120
to translate that correctly.
link |
02:09:47.160
I don't know what to do with that.
link |
02:09:48.720
So being Greek, it's very hard for me
link |
02:09:51.640
to think of a sentence or even a word
link |
02:09:54.480
without going into the full etymology of that word,
link |
02:09:59.000
breaking up every single atom of that sentence
link |
02:10:04.840
and every single atom of these words
link |
02:10:07.080
and rebuilding it back up.
link |
02:10:09.800
I have three kids.
link |
02:10:11.200
And the way that I teach them Greek
link |
02:10:13.680
is the same way that, you know,
link |
02:10:16.240
the documentary I was mentioning earlier
link |
02:10:17.640
about sort of understanding the deep roots
link |
02:10:19.720
of all of these, you know, words.
link |
02:10:23.880
And it's very interesting
link |
02:10:29.120
that every single time I hear a new word
link |
02:10:31.320
that I've never heard before,
link |
02:10:33.000
I go and figure out the etymology of that word
link |
02:10:34.720
because I will never appreciate that word
link |
02:10:36.760
without understanding how it was initially formed.
link |
02:10:40.160
Interesting, but how does that help?
link |
02:10:42.080
Because that's not the full picture.
link |
02:10:44.080
No, no, of course, of course.
link |
02:10:44.920
But what I'm trying to say is that knowing the components
link |
02:10:48.360
teaches you about the context of the formation of that word
link |
02:10:52.280
and sort of the original usage of that word.
link |
02:10:54.880
And then of course the word takes new meaning
link |
02:10:57.360
as you create it, you know, from its parts.
link |
02:11:00.840
And that meaning then gets augmented.
link |
02:11:04.120
And two synonyms that sort of have different roots
link |
02:11:08.160
will actually have implications
link |
02:11:09.200
that carry a lot of that baggage
link |
02:11:11.440
of the historical provenance of these words.
link |
02:11:14.240
So before working on genome evolution,
link |
02:11:16.640
my passion was evolution of language
link |
02:11:19.920
and sort of tracing cognates across different languages
link |
02:11:24.640
through their etymologies.
link |
02:11:27.280
That's fascinating that there's parallels between,
link |
02:11:30.320
I mean, the idea that there's evolutionary dynamics
link |
02:11:34.280
to our language.
link |
02:11:35.520
Yeah, every single word that you utter, parallels, parallels.
link |
02:11:41.560
What does parallels mean?
link |
02:11:42.680
Para means side by side.
link |
02:11:44.800
Alleles from alleles, which means identical twins.
link |
02:11:48.760
Parallels.
link |
02:11:49.600
I mean, name any word and there's so much baggage,
link |
02:11:53.200
so much beauty in how that word came to be
link |
02:11:56.880
and how this word took a new meaning
link |
02:11:58.920
than the sum of its parts.
link |
02:12:02.240
Yeah, and there's just, there's so many different words
link |
02:12:05.440
that are just words.
link |
02:12:06.280
They don't have any physical grounding.
link |
02:12:08.800
And now you take these words
link |
02:12:10.240
and you weave them into a sentence.
link |
02:12:13.600
The emotional invocations of that weaving are fathomless.
link |
02:12:19.280
And all of those emotions all live in the brains of humans.
link |
02:12:25.480
In the eye of the beholder.
link |
02:12:28.680
No, seriously, you have to embrace this concept
link |
02:12:30.840
of the eye of the beholder.
link |
02:12:32.440
It's the conceptualization that nothing takes meaning
link |
02:12:37.960
with one person creating it.
link |
02:12:39.400
Everything takes meaning in the receiving end
link |
02:12:42.480
and the emergent properties of these communication networks
link |
02:12:47.760
where every single, you know,
link |
02:12:49.320
if you look at the network of our cells
link |
02:12:50.960
and how they're communicating with each other,
link |
02:12:52.480
every cell has its own code.
link |
02:12:54.200
This code is modulated by the epigenome.
link |
02:12:56.200
This creates a bunch of different cell types.
link |
02:12:57.960
Each cell type now has its own identity.
link |
02:12:59.960
Yet they all have the common root of the stem cells
link |
02:13:02.200
that sort of led to them.
link |
02:13:04.760
Each of these identities is now communicating
link |
02:13:06.600
with each other.
link |
02:13:08.120
They take meaning in their interaction.
link |
02:13:11.800
There's an emergent property that comes
link |
02:13:13.760
from a bunch of cells being together
link |
02:13:15.680
that is not in any one of the parts.
link |
02:13:17.920
If you look at neurons communicating,
link |
02:13:19.320
again, these engrams don't exist in any one neuron.
link |
02:13:23.360
They exist in the connection and the combination of neurons.
link |
02:13:26.480
And the meaning of the words that I'm telling you
link |
02:13:29.040
is empty until it reaches you
link |
02:13:31.880
and it affects you in a very different way
link |
02:13:34.120
than it affects whoever's listening
link |
02:13:35.440
to this conversation now.
link |
02:13:37.520
Because of the emotional baggage that I've grown up with,
link |
02:13:40.400
that you've grown up with, and that they've grown up with.
link |
02:13:43.280
And that's, I think, the magic of translation.
link |
02:13:46.800
If you start thinking of translation
link |
02:13:48.720
as just simply capturing that emotional set of reactions
link |
02:13:53.720
that you evoke, you need a different set of words
link |
02:13:57.880
to evoke that same set of reactions to a French person
link |
02:14:01.240
than to a Russian person,
link |
02:14:02.760
because of the baggage of the culture that we grew up in.
link |
02:14:05.480
Yeah, I mean, there's...
link |
02:14:07.320
So basically, you shouldn't find the best word.
link |
02:14:10.440
Sometimes it's a completely different sentence structure
link |
02:14:13.120
that you will need,
link |
02:14:15.160
matched to the cultural context
link |
02:14:18.960
of the target audience that you have.
link |
02:14:20.560
Yeah, there's a lot of different words
link |
02:14:22.360
in the target audience that you have.
link |
02:14:23.800
Yeah, it's, I mean, you're just...
link |
02:14:26.480
I usually don't think about this,
link |
02:14:27.720
but right now, there's this feeling,
link |
02:14:30.000
as a reminder, that it's just you and I talking,
link |
02:14:32.680
but there's several hundred thousand people
link |
02:14:35.280
will listen to this.
link |
02:14:36.440
There's some guy in Russia right now running,
link |
02:14:40.840
like in Moscow, listening to us.
link |
02:14:44.120
There's somebody in India, I guarantee you.
link |
02:14:46.680
There's somebody in China and South America.
link |
02:14:48.680
There's somebody in Texas,
link |
02:14:51.240
they all have different...
link |
02:14:53.120
Emotional baggage.
link |
02:14:54.120
They probably got angry earlier on
link |
02:14:56.160
about the whole discussion about coronavirus
link |
02:14:58.360
and about some aspect of it.
link |
02:15:02.080
Yeah, and there's that network effect that's...
link |
02:15:06.960
It's a beautiful thing.
link |
02:15:08.000
And this lateral transfer of information,
link |
02:15:10.880
that's what makes the collective, quote unquote,
link |
02:15:12.920
genome of humanity so unique from any other species.
link |
02:15:17.920
Yeah.
link |
02:15:19.920
So you somehow miraculously wrapped it back
link |
02:15:22.640
to the very beginning of when we were talking
link |
02:15:25.160
about the beauty of the human genome.
link |
02:15:29.120
So I think this is the right time,
link |
02:15:31.240
unless we wanna go for a six to eight hour conversation.
link |
02:15:34.880
We're gonna have to talk again,
link |
02:15:36.000
but I think for now, to wrap it up,
link |
02:15:39.120
this is the right time to talk about
link |
02:15:41.080
the biggest, most ridiculous question of all,
link |
02:15:44.960
meaning of life.
link |
02:15:45.900
Off mic, you mentioned to me
link |
02:15:47.340
that you had your 42nd birthday.
link |
02:15:52.480
42nd being a very special, absurdly special number.
link |
02:15:58.480
And you had a kind of get together with friends
link |
02:16:03.040
to discuss the meaning of life.
link |
02:16:04.400
So let me ask you,
link |
02:16:05.920
in your, as a biologist, as a computer scientist,
link |
02:16:09.800
and as a human, what is the meaning of life?
link |
02:16:14.640
I've been asking this question for a long time,
link |
02:16:18.880
ever since my 42nd birthday,
link |
02:16:21.160
but well before that,
link |
02:16:22.080
in even planning the meaning of life symposium.
link |
02:16:25.280
And symposium, sim means together,
link |
02:16:29.800
posy actually means to drink together.
link |
02:16:31.520
So symposium is actually a drinking party.
link |
02:16:33.560
So the meaning.
link |
02:16:36.040
Can you actually elaborate about this meaning of life
link |
02:16:37.880
symposium that you put together?
link |
02:16:39.480
It's like the most genius idea I've ever heard.
link |
02:16:42.280
So 42 is obviously the answer to life,
link |
02:16:44.640
the universe and everything,
link |
02:16:45.600
from the Hitchhiker's Guide to the Galaxy.
link |
02:16:47.640
And as I was turning 42,
link |
02:16:49.560
I've had the theme for every one of my birthdays.
link |
02:16:51.800
When I was turning 32, it's one, zero, zero, zero, zero, zero
link |
02:16:55.640
in binary.
link |
02:16:56.640
So I celebrated my 100,000th binary birthday,
link |
02:17:00.080
and I had a theme of going back 100,000 years,
link |
02:17:03.640
let's dress something in the last 100,000 years.
link |
02:17:07.160
Anyway, it was, I've always had these.
link |
02:17:09.600
It's such an interesting human being.
link |
02:17:12.320
Okay, that's awesome.
link |
02:17:13.160
I've always had these sort of numerology
link |
02:17:17.400
related announcements for my birthday parties.
link |
02:17:21.800
So what came out of that meaning of life symposium
link |
02:17:27.360
is that I basically asked 42 of my colleagues,
link |
02:17:29.720
42 of my friends, 42 of my collaborators,
link |
02:17:33.080
to basically give seven minutes species
link |
02:17:35.520
on the meaning of life, each from their perspective.
link |
02:17:38.520
And I really encourage you to go there
link |
02:17:40.600
because it's mind boggling
link |
02:17:42.560
that every single person said a different answer.
link |
02:17:46.280
Every single person started with,
link |
02:17:48.480
I don't know what the meaning of life is, but,
link |
02:17:50.920
and then give this beautifully eloquently answer,
link |
02:17:54.240
eloquent answer.
link |
02:17:55.440
And they were all different,
link |
02:17:57.320
but they all were consistent with each other
link |
02:18:01.360
and mutually synergistic and together forming
link |
02:18:04.360
a beautiful view of what it means to be human in many ways.
link |
02:18:08.560
Some people talked about the loss of their loved one,
link |
02:18:12.280
their life partner for many, many years
link |
02:18:14.520
and how their life changed through that.
link |
02:18:16.520
Some people talked about the origin of life.
link |
02:18:19.280
Some people talked about the difference
link |
02:18:21.080
between purpose and meaning.
link |
02:18:24.160
I'll maybe quote one of the answers,
link |
02:18:28.600
which is this linguistics professor,
link |
02:18:30.880
friend of mine at Harvard, who basically said,
link |
02:18:35.880
that she was gonna, she's Greek as well.
link |
02:18:37.800
And she said, I will give a very Pythian answer.
link |
02:18:40.120
So Pythia was the Oracle of Delphi,
link |
02:18:42.960
who would basically give these very cryptic answers,
link |
02:18:45.280
very short, but interpretable in many different ways.
link |
02:18:48.320
There was this whole set of priests
link |
02:18:50.480
who were tasked with interpreting what Pythia had said.
link |
02:18:53.440
And very often you would not get a clean interpretation,
link |
02:18:56.440
but she said, I will be like Pythia
link |
02:18:59.000
and give you a very short and multiply interpretable answer.
link |
02:19:02.520
But unlike her, I will actually also give you
link |
02:19:04.800
three interpretations.
link |
02:19:07.000
And she said, the answer to the meaning of life
link |
02:19:09.800
is become one.
link |
02:19:12.840
And the first interpretation is like a child,
link |
02:19:16.320
become one year old with the excitement
link |
02:19:18.720
of discovering everything about the world.
link |
02:19:21.400
Second interpretation, in whatever you take on,
link |
02:19:25.040
become one, the first, the best, excel,
link |
02:19:28.840
drive yourself to perfection for every one of your tasks
link |
02:19:32.600
and become one when people are separate,
link |
02:19:38.480
become one, come together, learn to understand each other.
link |
02:19:43.600
Damn, that's an answer.
link |
02:19:45.400
And one way to summarize
link |
02:19:46.880
this whole meaning of life symposium
link |
02:19:48.760
is that the very symposium was illustrating
link |
02:19:52.920
the quest for meaning,
link |
02:19:54.680
which might itself be the meaning of life.
link |
02:19:58.120
This constant quest for something sublime,
link |
02:20:01.400
something human, something intangible,
link |
02:20:04.880
some aspect of what defines us as a species
link |
02:20:09.680
and as an individual.
link |
02:20:11.320
Both the quest of me as a person through my own life,
link |
02:20:16.360
but the meaning of life could also be
link |
02:20:19.200
the meaning of all of life.
link |
02:20:20.840
What is the whole point of life?
link |
02:20:22.040
Why life?
link |
02:20:22.880
Why life itself?
link |
02:20:24.480
Because we've been talking about the history
link |
02:20:26.720
and evolution of life,
link |
02:20:28.360
but we haven't talked about why life in the first place?
link |
02:20:31.080
Is life inevitable?
link |
02:20:32.520
Is life part of physics?
link |
02:20:35.880
Does life transcend physics
link |
02:20:37.720
by fighting against entropy,
link |
02:20:40.320
by compartmentalizing and increasing concentrations
link |
02:20:42.960
rather than diluting away?
link |
02:20:45.320
Is life a distinct entity in the universe
link |
02:20:51.520
beyond the traditional very simple physical rules
link |
02:20:55.080
that govern gravity and electromagnetism
link |
02:20:58.560
and all of these forces?
link |
02:21:00.600
Is life another force?
link |
02:21:02.120
Is there a life force?
link |
02:21:03.120
Is there a unique kind of set of principles that emerge,
link |
02:21:05.920
of course, built on top of the hardware of physics,
link |
02:21:09.080
but is it sort of a new layer of software
link |
02:21:11.840
or a new layer of a computer system?
link |
02:21:14.400
And so that's at the level of big questions.
link |
02:21:18.480
There's another aspect of gratitude
link |
02:21:21.200
of basically what I like to say is,
link |
02:21:27.000
during this pandemic,
link |
02:21:27.920
I've basically worked from 6 a.m. until 7 p.m.
link |
02:21:30.800
every single day, nonstop, including Saturday and Sunday.
link |
02:21:34.280
I've basically broken all boundaries
link |
02:21:36.440
of where life, personal life begins
link |
02:21:39.120
and work life ends.
link |
02:21:42.000
And that has been exhilarating for me,
link |
02:21:46.280
just the intellectual pleasure that I get
link |
02:21:50.480
from a day of exhaustion,
link |
02:21:53.840
where at the end of the day, my brain is hurting.
link |
02:21:55.520
I'm telling my wife, wow, I was useful today.
link |
02:22:00.360
And there's a certain pleasure
link |
02:22:04.720
that comes from feeling useful.
link |
02:22:08.360
And there's a certain pleasure
link |
02:22:09.880
that comes from feeling grateful.
link |
02:22:12.440
So I've written this little sort of prayer for my kids
link |
02:22:16.440
to say at bedtime every night,
link |
02:22:19.520
where they basically say,
link |
02:22:21.000
thank you, God, for all you have given me
link |
02:22:24.720
and give me the strength to give onto others
link |
02:22:28.560
with the same love that you have given onto me.
link |
02:22:33.160
We as a species are so special,
link |
02:22:36.560
the only ones who worry about the meaning of life.
link |
02:22:40.800
And maybe that's what makes us human.
link |
02:22:44.680
And what I like to say to my wife and to my students
link |
02:22:47.960
during this pandemic work extravaganza
link |
02:22:53.280
is every now and then they ask me, but how do you do this?
link |
02:22:56.400
And I'm like, I'm a workaholic.
link |
02:22:58.880
I love this.
link |
02:23:00.880
This is me in the most unfiltered way.
link |
02:23:04.800
The ability to do something useful,
link |
02:23:07.280
to feel that my brain is being used,
link |
02:23:09.640
to interact with the smartest people on the planet
link |
02:23:12.600
day in, day out, and to help them discover aspects
link |
02:23:15.880
of the human genome, of the human brain,
link |
02:23:18.520
of human disease and the human condition
link |
02:23:21.960
that no one has seen before
link |
02:23:24.560
with data that we're capturing that has never been observed.
link |
02:23:29.880
And there's another aspect, which is on the personal life.
link |
02:23:34.480
Many people say, oh, I'm not gonna have kids, why bother?
link |
02:23:37.560
I can tell you as a father,
link |
02:23:41.280
they're missing half the picture, if not the whole picture.
link |
02:23:44.560
Teaching my kids about my view of the world
link |
02:23:49.040
and watching through their eyes
link |
02:23:51.200
the naivete with which they start
link |
02:23:53.480
and the sophistication with which they end up,
link |
02:23:56.920
the understanding that they have
link |
02:24:00.080
of not just the natural world around them, but of me too.
link |
02:24:05.120
The unfiltered criticism that you get from your own children
link |
02:24:10.120
that knows no bounds of honesty.
link |
02:24:15.200
And I've grown components of my heart
link |
02:24:18.840
that I didn't know I had
link |
02:24:20.800
until you sense that fragility,
link |
02:24:25.000
that vulnerability of the children,
link |
02:24:30.360
that immense love and passion,
link |
02:24:34.040
the unfiltered egoism,
link |
02:24:36.560
that we as adults learn how to hide so much better.
link |
02:24:40.080
It's just this back of emotions
link |
02:24:43.720
that tell me about the raw materials that make a human being
link |
02:24:48.720
and how these raw materials can be arranged
link |
02:24:50.880
with more sophistication that we learn through life
link |
02:24:53.880
to become truly human adults.
link |
02:24:57.760
But there's something so beautiful
link |
02:24:59.960
about seeing that progression between them
link |
02:25:02.480
and seeing that progress and that progress
link |
02:25:05.040
and that progression between them,
link |
02:25:07.280
the complexity of the language growing
link |
02:25:10.600
as more neural connections are formed
link |
02:25:13.720
to realize that the hardware is getting rearranged
link |
02:25:18.560
as their software is getting implemented on that hardware,
link |
02:25:22.640
that their frontal cortex continues to grow
link |
02:25:24.880
for another 10 years.
link |
02:25:27.840
There's neuronal connections that are continuing to form,
link |
02:25:29.960
new neurons that actually get replicated and formed.
link |
02:25:33.120
And it's just incredible that we have these,
link |
02:25:38.120
not just you grow the hardware for 30 years
link |
02:25:40.680
and then you feed it all of the knowledge.
link |
02:25:42.640
No, no, the knowledge is fed throughout
link |
02:25:45.200
and is shaping these neural connections as they're forming.
link |
02:25:48.480
So seeing that transformation from either your own blood
link |
02:25:52.840
or from an adopted child
link |
02:25:54.560
is the most beautiful thing you can do as a human being.
link |
02:25:57.520
And it completes you, it completes that path, that journey.
link |
02:26:00.760
The create life, oh sure, that's at conception, that's easy.
link |
02:26:04.880
But create human life to add the human part,
link |
02:26:08.400
that takes decades of compassion, of sharing,
link |
02:26:13.160
of love and of anger and of impatience and patience.
link |
02:26:18.640
And as a parent,
link |
02:26:21.880
I think I've become a very different kind of teacher
link |
02:26:25.960
because again, I'm a professor.
link |
02:26:27.080
My first role is to bring adult human beings
link |
02:26:31.040
into a more mature level of adulthood
link |
02:26:34.440
where they learn not just to do science,
link |
02:26:37.040
but they learn the process of discovery
link |
02:26:39.840
and the process of collaboration, the process of sharing,
link |
02:26:42.280
the process of conveying the knowledge
link |
02:26:44.840
of encapsulating something incredibly complex
link |
02:26:48.000
and sort of giving it up in sort of bite sized chunks
link |
02:26:51.200
that the rest of humanity can appreciate.
link |
02:26:54.400
I tell my students all the time, if you, you know,
link |
02:26:57.440
like when an apple fall,
link |
02:26:58.720
when a tree falls in the forest
link |
02:27:00.840
and no one's there to listen, has it really fallen?
link |
02:27:03.040
The same way you do this awesome research,
link |
02:27:05.280
if you write an impenetrable paper that no one will understand,
link |
02:27:08.640
it's as if you never did the awesome research.
link |
02:27:11.040
So conveying of knowledge, conveying this lateral transfer
link |
02:27:15.200
that I was talking about at the very beginning
link |
02:27:17.520
of sort of humanity and sort of the sharing of information,
link |
02:27:22.480
all of that has gotten so much more rich
link |
02:27:27.200
by seeing human beings grow in my own home
link |
02:27:32.240
because that makes me a better parent
link |
02:27:35.080
and that makes me a better teacher and a better mentor
link |
02:27:38.920
to the nurturing of my adult children,
link |
02:27:42.240
which are my research group.
link |
02:27:43.960
First of all, beautifully put, connects beautifully
link |
02:27:48.280
to the vertical and the horizontal inheritance of ideas
link |
02:27:52.240
that we talked about at the very beginning.
link |
02:27:54.440
I don't think there's a better way to end it
link |
02:27:57.320
on this poetic and powerful note.
link |
02:28:01.320
Manolis, thank you so much for talking to me.
link |
02:28:02.920
It was a huge honor.
link |
02:28:03.760
We'll have to talk again about the origin of life,
link |
02:28:07.240
about epigenetics, epigenomics,
link |
02:28:10.520
and some of the incredible research you're doing.
link |
02:28:13.600
Truly an honor. Thanks so much for talking to me.
link |
02:28:15.320
Thank you. Such a pleasure. It's such a pleasure.
link |
02:28:17.240
I mean, your questions are outstanding.
link |
02:28:19.080
I've had such a blast here and I can't wait to be back.
link |
02:28:21.880
Awesome.
link |
02:28:23.240
Thanks for listening to this conversation
link |
02:28:24.800
with Manolis Kellis, and thank you to our sponsors,
link |
02:28:28.000
Blinkist, 8sleep, and Masterclass.
link |
02:28:31.360
Please consider supporting this podcast
link |
02:28:33.200
by going to blinkist.com slash lex,
link |
02:28:35.640
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link |
02:28:41.040
Click the links, buy the stuff, get the discount.
link |
02:28:44.160
It's the best way to support this podcast.
link |
02:28:47.040
If you enjoy this thing, subscribe on YouTube,
link |
02:28:48.800
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link |
02:28:50.920
support it on Patreon,
link |
02:28:52.280
or connect with me on Twitter at lexfreedman.
link |
02:28:55.480
And now let me leave you with some words
link |
02:28:57.360
from Charles Darwin that I think Manolis
link |
02:29:00.080
represents quite beautifully.
link |
02:29:02.600
If I had my life to live over again,
link |
02:29:04.840
I would have made a rule to read some poetry
link |
02:29:07.560
and listen to some music at least once every week.
link |
02:29:11.640
Thank you for listening, and hope to see you next time.