Stephen Meyer: Darwin’s Doubt

[Music] thank you wasn't that a terrific talk in the last hour I did my PhD work on the origin of life problem I wrote the big books signature in the cell and it's just tremendous to listen to Jim explain the details of the chemistry that have to be overcome that have to be manipulated the sequencing problem all of that it's just fascinating and it as I was listening to him it reminded me of something that I wrote in the prologue to Darwin's doubt which I'll be talking about in this hour which is not about the problem of the of chemical evolution the which is the attempt to explain the origin of the first life from simpler nonliving chemicals but rather the problems faced by biological evolution and in the prologue to to my book I wrote that rarely has there been such a great disparity between the popular perception of a theory and its actual standing in the relevant peer-reviewed scientific literature sound familiar this kind of same thing that Jim was just saying about prebiotic chemistry and chemical evolution today modern neo-darwinism seems to enjoy almost universal acclaim among science journalists bloggers biology textbook writers and other popular spokespersons for science as the great unifying theory of all biology but then I go on to say but there's book problems with the theory that are being reported in the peer-reviewed literature that are not being reported to the public and this idea came home to me with great force here in the state of Texas 2009 okay so I'm testifying 2009 Texas State Board of Education they have a standard that they're considering to encourage teachers to teach the strengths and weaknesses of competing scientific theories seems like sweet reason to almost everybody but the Darwin only science education Lobby turns up in force and they says you can't and they say we you can't apply that standard to Darwinian theory because and this is Eugenie Scott speak to the Dallas Morning News at the time there are no weaknesses in the theory of evolution and I thought them is a kind of very common statement did you hear you know and but I thought it was breathtaking I was there to testify I had 100 peer-reviewed papers to submit in evidence of significant problems with contemporary theory of evolution known as neo-darwinism the standard textbook theory that we all have been taught and is still being taught in modern high school and college biology texts the Theory emphasizes the role the creative power of mutation and natural selection many leading evolutionary biologists to say nothing of molecular cell developmental or other types of biologists have been have been pointing out problems with that claim for a long time the mechanism does a good job of explaining small-scale variation peppered mahse have their wings during light and dark and light again or finchy Biggs to get a little bigger a little smaller in response to varying environmental conditions but it does a really it doesn't pour in an adequate job of explaining the origin of birds or moths or insects or mammals or animals in the first place and so I I testified at the hearing but I found this was really striking and you get of course he said this the same kind of overstatement next slide please in in lots of popular presentations of the theory this is of course Richard Dawkins I love this because he just he's such delicious invective against people disagrees is it's absolutely safe to say that if you meet somebody who claims not to believe in evolution that person is either ignorant stupid or insane but then you know he he's so kind here he says or wicked but I'd rather not consider that so we had this little thing going on at one of the main news and public affairs magazines right now and a writer has called intelligent design a rube bait idea rube ate intelligent and when when my book first came out one of the Amazon reviewers called it mendacious intellectual pornography you know so you get you get this wonderful invective anyway there is the public presentation of the theory every reasonable person agrees Michael ruse at one point said it's fact fact fact but yet you get into that you get into the peer-reviewed literature you start talking to people who were actually wrestling with these issues at a scientific level and it's not so simple so next slide this this really came home to a number of us at this meeting at the Royal Society in 2016 we're leading evolutionary biologists called a meeting to discuss the need for a new theory of evolution and what the next slide the the the conference kicked off with a presentation from GERD Muller a leading Austrian theoretical and evolutionary biologist with a talk titled the explanatory deficit of the modern synthesis the modern synthesis is another name for neo-darwinism which synthesized classical Darwinian theory with something called population to genetics to give evolutionary theory of mathematical basis and Muller went on to explain next slide please the several he had a list of five but I for this purpose list three of the major explanatory deficits things that neo-darwinism can't explain it doesn't explain the origin of phenotypic complexity the phenotype refers to divisible attributes of the an organism's body and so organisms are really complex they have an integrated complexity neo-darwinism doesn't explain that he went on to say it doesn't explain the origin of anatomical novelty good again does a good job explaining the small scale variations but not the major innovations that occur in the history of life is documented by the fossil record the big changes and it doesn't explain the origin of non gradual modes of transition that's another way of talking about abrupt change in the fossil record where fundamentally new forms of life emerge very abruptly without any connection to similar forms in lower in lower strata so it happens that next slide I wrote a book about this the last two issues the book is Darwin's doubt and it's about the the mystery of the Cambrian explosion and-and-and the Cambrian explosion relates to the points that Muller was making because it is an event in the history of life that documents the abrupt appearance of major new morphology or new forms of life and in fact almost all of the major groups of animals arise abruptly in the Cambrian period now next slide please so the Cambrian explosion we can define as a geologically abrupt or sudden appearance of most of the major animal groups and body plants where a body plan is a unique configuration of or arrangement to use the word that Jim use a very important thing in biology we were talking about arranging of parts so it's a body plant is a unique arrangement of body parts and tissues and you see in this this different line up here a number of the different major phyla where the phyla represents the that is the largest division of classification among the animals and they would correspond to specific body plans and so you might look at for example on the far right you've got the arthropods they have a hard exoskeleton and just to the left then we have the chordates and those are things like fishes or us which have either an internal notochord or a vertebrae and a skeletal system internal to the body this is a totally different body logic and depending on whether you have an exoskeleton and an internal skeleton the your gonna arrange the the organism is required going to require very different arrangement of parts to have a functional integrity and so these body plans are real divisions of a way conceptually but also exemplified in real organisms very different ways of of being alive and these very different ways of being alive or come into existence very abruptly in the Cambrian period next slide please so here's a depiction I love this slide one of our our slide designers did this for us so it packs a lot of information on the right hand side we have the sedimentary record the left-hand side the standard geological timescale in millions of years and then we have just some of the many organisms that arose in this Cambrian period which is dated about 520 to 530 million years ago and so it's a very abrupt geologically sudden emergence of these new forms of life with in almost all of these cases no discernable connection to any similar form of life in the lower late Precambrian strata and that's the that's the mystery okay next next slide so again that's give you a picture of the geologic time scale and the how abrupt the explosion is next slide so here's here's that here's the rub of the problem especially from an evolutionary or Darwinian point of view Darwin deep not only proposed the mechanism of natural selection and random variation and now we would talk about random mutations to explain the origin of these new forms of life but the nature of the mechanism requires it to work very gradually over long periods of time it's a mechanism that accumulates incremental change little by little by little as those incremental changes allegedly confer some functional advantage on the organism in which they occur and so the the the the mechanism must work very gradually Darwin also argued on independent grounds that the history of life could be best depicted as a gradually unfolding branching tree where the base of the tree would represent something like that first one celled organism that the origin of life people are trying to explain and then all the other forms of life are morphing and changing and branching off from that until finally we get to you know this would be the the tree leading to the first animals we could all we could extend that tree all the way to the present think of all the forms of life that exist today but this is this is the the picture of the history of life or the vertical axis is time the horizontal access axis is morphological change or distance so we got lots of lots of different forms of life arising and but they're alleged to have done so very gradually with many transitional intermediates leading on the way to those first animal forms in fact what we find in the fossil record is next slide please a very strikingly divergent picture because the the major groups of organisms do arise very abruptly and so the next slide shows the tension between the data and the theory and this is that this is the the problem known as the Cambrian explosion now Darwin next slide was very aware of this and in the Origin of Species discussed it quite extensively and he said as to the question why we do not find rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system I can give no satisfactory answer and so he left this as an unsolved mystery and in my book I call it Darwin's doubt I didn't mean to imply and I've clarified this that Darwin woods didn't doubt that he had it right he thought his theory was correct but he he was aware that he had there were classes of evidence that his theory couldn't adequately explain and they did give him pause and this is evidence of that of that of that doubt about the adequacy of the theory or its ability to explain all the evidence even if he wasn't at the end of the day going to doubt his basic concept of evolution by natural selection okay so I call this in the book next slide the mystery of the missing fossils and that mystery Darwin thought would be resolved by future fossil finds you might have noticed that in the conference so far there's been a little bit of a reversal of a narrative you often hear that it's the advance of science that makes the god hypothesis unnecessary it's the advance of the hypothesis that makes you know the evidence of design evaporate well no it's actually been just the opposite the more we've learned about the fine-tuning the more acute the problem has been the more we've learned about cosmology and we're confident we are the universe had a beginning and in biology the more we learned about fossils the more distinct this pattern of discontinuity has become Darwin hoped that in the ensuing years after 1859 there would be new fossil finds that would fill in those missing ancestral forms that were represented by the blue dots on my diagram a bit ago and this was called the artifact hypothesis by later paleontologists and the idea was that the that the missing ancestral forms that we expect to find aren't there as because they're that's just an artifact of incomplete sampling of the fossil record we haven't looked hard enough or else it's an artifact of incomplete preservation for some reason or another the depositional environments were capable of preserving the the ancestral precursors now after a hundred and sixty some odd years since the publication of the Origin of Species the pattern of abrupt appearance discontinuity and then what paleontologists call stasis where major groups of organisms persist through the fossil record without significant directional change in their structure that pattern has become much more pronounced not less pronounced and one of the fossil finds that that that established or reinforced that pattern for the Cambrian explosion was the great fine that Stephen Jay Gould wrote about in the Burgess Shale in Canada and if some of you are discovery supporters we did a big trip up there two summers ago and it was fantastically hiked to the top of the birches and saw the wonderful fossils but another find more recent in the 1980s right up to the present is they find in southern China the the Mao Shan Shale and they're tiny was so dramatic that Time magazine did a cover story on this in 1995 they called it evolutions big bang one of the paleontologists in the in the article quoted said what I like to ask my evolutionary biologist friends is this how much faster does this event have to happen before we stop stop calling it evolution because what they found was that the time the timeframe of the Cambrian explosion shrunk further and the number of different dis disparate morphological forms increased completely new animal forms that were unknown before but they also very abruptly in the fossil record the standard date now for the time the Cambrian explosion is about a ten million year window but the the there were thirteen to sixteen new body plans that emerged within a five-year five to six million year window within just a few feet of sediment and this is just extraordinary it's you know within the error bars at paleontological time measuring and so this is really dramatic and five to six million years may not sound a lot also from a biological point of view but this is also biologically abrupt there's a whole branch of the evolutionary biology called population genetics which is in that way by which if you know certain factors you can estimate how much evolutionary change could occur in a given amount of time or conversely if a given enough time if a certain amount of time is enough time for a given amount of evolutionary change to occur and the factors are popular population size generation time from one parent to offspring and mutation rates and on that basis five to six million years is also a blink of the eye there's a mathematical biology team at Cornell that looked at some Michael Behe made an argument based on population genetics in his book the edge of evolution and he argued that to get two coordinated mutations in the hominid line it would take about a half a billion years about five hundred million years and these mathematical biologists at Cornell came back and said no no no that's that's not right we worked that rework the math it would only be two hundred and sixteen million years to get two coordinated mutations the the alleged chimp human divergence is five to six million years ago it was a moot point and it takes a lot more than two coordinated mutations to build a whole new form of animal life and so you know if I five to six million a year window a ten million year window give the Cambrian P you know the people twenty forty whatever it's not nearly enough time on the Darwinian mechanism to build the amount of new structure that's required that new morphologic and the new morphology so the explosions abrupt geologically its abrupt biologically and and so this is this has been a big mystery and I've called this in my book the first the first mystery next slide is the I called the mystery of the missing fossils and this this came home in a particularly poignant way in the year 2000 we at Discovery Institute in conjunction with one of our research fellows who's a marine paleo biologist Paul Qin were able to host a lecture from one of the leading Chinese paleontologists jy Chen at the University of Washington locally in Seattle and jy Chen was is one of the Chinese paleontologists who was finding all these wonderful new forms of life in the Cambrian strata they're beautifully preserved and word got out that he was going to bring fossils to this this talk and we had a really good audience of paleontologists and geologists and and evolutionary biologists and Chen gave a wonderful talk about what had been found the difference the stratigraphy there the they showed him a number of the different fossil finds and later in his talk he said you know this this whole discovery turns Darwin's Tree of Life and he held his hand up like this upside down and whereas in the tree of life the major differences in form arise as the result of a gradual transformation simple to complex over a long period of time that's the Darwinian picture but instead he's pointed out that the major differences in form were present right from the beginning and they were disparate they were very different from each other as man as exemplified in these different different body plans and so he said it turned the Tree of Life upside down there's even been in 1995 an article in people's daily talking about the problems of Darwinian theory and so this when he when he started to talk about the evolutionary implications of this finding there was a lot of uncomfortable shuffling of feet in the room and when we got to the Q&A one of the local university of washington professors in earth science said you know professor Chen that was a wonderful talk we'd love seeing the fossils but aren't you a little uneasy about talking about the this challenge to neo-darwinism it was more a warning than he shouldn't be but anyway he said aren't you a little uneasy talking about this the way these fossils challenged Darwinian theory coming as you do so from such an authoritarian country and that suddenly made things very uncomfortable because now not only had he kind of put the professor on warning he shouldn't be questioning Darwinism but he now insulted China which I thought was kind of in poor taste and but professor Chen was in and didn't miss a beat he was not thrown off by this at all and he just said oh he said no he said in in China we can question Darwinism just not the government and he then said in the United States he said you you you can question the government but you mustn't question Darwinism he said and he'd heard about our politically correct institutions so anyway this is the mystery of the missing fossils the the absence of ancestral intermediates the abrupt appearance of disparate forms of life without those precursors that are alleged to have produced that produced them on Darwinian grounds ok so that's and in my book I deal I have a lot about this and deal with various attempts to explain away this mystery but I think it's pretty clear now that mystery is persisted in fact recently I've done an article with the german paleontologist gunther Beckley so we're leading insect paleontologists in the world we've written another article in another volume about 17 similar explosions in the history of life this is this is the dominant pattern in the fossil record abrupt appearance and stasis it's not just the Cambrian period where we have this all right next slide so that going forward to go the other next slide maybe I've reviewed it ok that's the mystery of the missing fossils but there is a more fundamental mystery and that's what I really want to talk about in the in the rest of the time we have together so next slide discusses the real mystery and that is how do you build an animal or rather how would the evolutionary process build an animal form and that that mystery has become more acute it's not just the absence of the for the fossil intermediates it's really the engineering problem that's involved I didn't bring it this time I wish I had but I have a lovely sample of a trilobite one of those our Cambrian arthropods and in this particular specimen I have you can see the compound eyes and this is a very sophisticated visual apparatus insects modern insects have them and the but these compound eyes apparently existed from the very dawn of animal life there's no gradual working up to this you've got a very sophisticated visual apparatus right in the first animals it's incredible okay so how do you how would you build something like that how would you build all these different cell types all the different morphological structures involved in all these different forms of life how would the evolutionary process do that especially in the limited time that it apparently had but even if you had more time how could that be accomplished next slide this this this was of course the the the problem that Muller was highlighting he also had an earlier book with another biologist Stuart Newman from NYU and on page 7 is a really seminal book MIT press 2003 on the origination of organismal form they argue that neo-darwinism has as they put it no theory of the generative it does a really good job of preserving small advent a advantageous changes but it doesn't do a good job of innovation and in that they had a list of unsolved problems from neo-darwinism one of which was the origin of organismal form and I thought my goodness isn't that what Darwin is supposed to have explained back in 1859 did anyone not I mean the word simply that's another case the word hasn't gotten out there was no recall on that idea okay next slide so the it turns out that there's three main challenges to well actually there's four that I addressed in the book but I'm gonna address try to get through three we'll see how we do on time but I wanna I want to give you an I want to explain why there is growing skepticism about leading evolutionary biologists and mathematical biologists about the adequacy of the Mutai selection mechanism as an explanation for building new forms of animal life this is the engineering problem how do you how would the evolutionary process build those forms next slide so this problem became very much more acute as the result of something we've been talking a fair bit about in this conference you had next slide please and that is the problem of the origin of genetic information and again next slide we if we look at the abrupt appearance of all these new animal forms we now know that to build these new forms of life we need a lot of new information every new for every new form of animal life has lots of new anatomical structures new tissues new tissues are made of new we have new organs and tissues in the new body plant organs and tissues are made of distinct cell types so for example you have an animal with a gut you have to you have to have digestive enzymes enzymes in the gut but enzymes are proteins and proteins have to be built in accord with the information stored on another molecule let's skip forward till we see Watson and Crick here could we get to so you want to build new proteins you've got to have the information on the new information in DNA and so essentially the Cambrian explosion and other fossil explosions like that documented in the fossil record are not only explosions of new form of new biological form and structure they're explosions of new information and that raises a really big question where does that information come from next slide why you may remember 1953 I discussed this really briefly last night but Watson Crick elucidate the structure of DNA in 1953 in 1957 Crick who was a codebreaker in World War two I find this fascinating he's realizing that the informational attributes of the whole gene expression system and he posits the idea that DNA is encoding information in a digital form and that the four characters the the bases the a's t's g's and C's that we represent the chemists represent used to represent these nucleotide bases that they're functioning like alphabetic characters in a written language or digital characters in the machine code and this is this is a really important moment in the history of biology I mean this is this is stunning really if you stop and think about it that I used an example and signature in the cell of someone you know going to Antarctica and going and finding a cave and being pretty sure there was never any intelligent life ever on Antarctica before we get there in 1909 or whenever it was first really explored going in the cave and then finding complex hieroglyphic inscriptions written on the wall you get to some place you go inside this enclosure and there's there's information in a code script and this is essentially what biologists found in in the 1950s and and Crick posited this this sequence hypothesis and over the next seven to eight years by about 1965 the the scientists were pretty confident that he was right the molecular biologists working on both sides of the Atlantic and they had elucidated what's now known as the gene expression system or the system for protein synthesis we don't have time to show you this right now but there's a little nice little animation on my website and also on YouTube called journey inside this cell that shows how the digital information in the DNA molecule is used to build protein molecules and protein machines enzymes are one type of protein that dr. tor was talking about in the last session so next slide so this is the problem how do you get the new information not just to build proteins but to build whole new animal forms so you see this new animal forms you know that at the very least are going to require a lot of new proteins to service the new types of cells that are represented in those forms of life now the Darwinian explanation for that is that you have these random changes in the sequence of those nucleotide bases the essentially the genetic letters or the genetic characters in the in the in the digital code stored in the DNA molecule and that those random changes will confer some advantages they'll generate new information for building new proteins and you'll be able to build up these new structures that way as a result of these small incremental variations being and passed on now the product that the problem with that starts with a really an understanding of the kind of information that we have in DNA there are two types of information at least but this is the analytic there's a distinction that we need to be really clear on Claude Shannon the founder of modern mathematical information theory had defined information in terms of the exclusion of possibilities or the reduction of uncertainty and so in his mathematical theory that top sequence would be would have a lot of information or information carrying capacity he could measure the improv his theory allowed us to measure the improbability of a sequence of characters in a string like that but it didn't allow us to distinguish between functional and non functional information or meaningful and non meaningful information so you can see that in addition to you've got two very improbable strings of characters but there's a qualitative difference between the two isn't there everyone see it one is performing the communication function the other as far as we can tell is gibberish but both have an equivalent amount of Shannon information measured mathematically as a measure of the improbability of the sequences okay so when we're talking about information in biology and Crick was very clear on this right from the beginning we're not talking about merely Shannon information we're talking about information that performs a function and in the biological context it's the function of providing the instructions for building functional proteins okay next slide so the problem with the neo-darwinian mechanism is that it's relying on an undirected process of change mutant called mutation to change the character string without any concern for the outcome the the processes that produce mutation are random in the sense that they are not occurring with respect to the organism survival needs they could be any any any type of change but our experience of computer code is told us that this is not a really good way to generate new information any software developers or program here okay if you get a you know a random change to yours if you got a nice piece of software or a program or operating system you don't want I suspect random changes to your zeros and ones right bugs and glitches are the enemy of proper function they're overwhelmingly more likely to degrade function than to settle on something new that's going to be useful and functional and and so our experience of computer code is made a lot of scientists really skeptical about the this mechanism and next slide and this this and there's a mathematical reason for that if you have a if you make a series of random changes to a functional sequence of text or a functional sequence of computer code you're overwhelmingly more likely to degrade function than to build something new why is that that's because there's so many more ways to go wrong than there are to go right so for just a simple example for any 12 letter sequence in English if you had a meaningful sequence of 12 letters in English there are ten a hundred trillion other possible ways of arranging those same letters that don't convey meaning in English the functional sequences are extremely rare in comparison to the possible sequences and this turns out to be true of virtually of all communication systems that use use alphabetic digital or typographic characters okay so next slide so in the 1960s after it became really clear what was going on with the molecular biological revolution and that that molecular biologists had basically discovered information embedded in these large macromolecules the a lot of mathematicians who were following this or mathematically inclined scientists started to get really skeptical and there was a famous picnic at MIT in 1965 at the home of Victor Weisskopf a famous physicist and at that picnic there were biologists evolutionary biologists computer scientists mathematicians and and the quantitative science scientists and the biologists got into quite a heated argument over at this picnic about whether or not neo-darwinism could really explain the evolution the origin of new forms of life and this this argument was was inspired by the new discoveries that we're being made in the basically the mathematically inclined scientists were saying well if what you guys are saying you biologists are saying is true about DNA and proteins and their information-bearing properties we don't see how your origin story holds up we don't see how the neo-darwinian mechanism could be responsible because what we know about about computer code is that you start changing that randomly you're gonna degrade function you're not gonna get something new and good and helpful and so this is this is they they decided as a result of this discussion to break this out into a larger discussion and have a conference and it was a now-famous conference held in 1966 at the Wistar Institute in Philadelphia called mathematical challenges to neo-darwinism and there were scientists on both sides of this one of the the initiators of the conference Murray Eden very high powered computer science professor there I had I had the privilege of meeting him at 89 in a conference 40 years on commemorating this still sharp as a tack and but this is what he said he said no currently existing existing formal language can tolerate random changes in the symbol sequences which expressed its sentences meaning is almost invariably destroyed and and again the reason for that which even explained beautifully in his talk at this conference and the proceedings were still are these are beautiful proceedings of you if you have a chance to get them next slide and the meaning and the reason for this is again lots more ways to go wrong than there are to go right now let me break this down into really fun example I alluded to this last night in the in the interview with Eric but if you if you want to a combination that opens a lock is an information-rich sequence it's only got four characters but it provides information for performing a function so let's imagine we we have outside the the auditorium here we have a nice a nice bicycle that's locked with one of these four dial locks if there's if I tell you that there's a thief that's coming up to have a go at the lock to see if he can steal the bicycle is it is it more likely that the thief is gonna succeed or fail to open the lock via a random search for the combination and I kind of I kind of gave this away last night in the interview but the standard answer I'll get from an audience when I pose this rhetorically is oh he's gonna fail more likely than you fail when they say wait a minute is a trick question because we need to know something else don't we need to know how many opportunities the thief has how diligent is this thief and you know I once did this math if the thief changed one dial you know what tried a different combination once every ten seconds in a little over 15 hours the thief could sample about five thousand a little bit of more than five thousand of the combinations well in this particular lock you've got four times ten or ten to the fourth possibilities which is 10,000 combinations so if the thief is gonna stay out there for 15 hours and we don't have any police walking the block it's it actually becomes more likely than not that the thief will succeed but what if the thief encounters this lock next slide please now he's got a little bit of a different problem on his hand and this gets back to the great illustration that Jim used about exponential numbers because now we've got ten times ten possibilities not 10 times 10 times 10 10 to the fourth and we got 10 to the 10 possibilities which is 10 billion now if you do that same lock and you give the thief a hundred years and the thief does nothing but change the dial every 10 seconds no potty breaks no dates no you know no meals the thief will only sell we'll only be able to sample a very small percentage about 3% of the total number of combinations in a hundred years now and so in that case we have to ask is it more likely that the thief will succeed or fail we ask again is it more likely that the people fail or succeed in opening the lock via a random search now it's more it's overwhelmingly more likely that the thief will fail rather than succeed you see the probabilistic reasoning involved there's all a chance but the question is is the chance hypothesis more likely to be true or false if it's overwhelmingly more likely that the thief will fail then the hypothesis that the thief will succeed is more likely to be false and true okay and in science we really prefer not to affirm hypotheses that we know are more likely to be false and true okay we go on and look for a better explanation okay so now what stuff what's all this have to do with the Cambrian explosion and the origin of information well this illustrates the problem that the mutation selection mechanism encounters in trying to generate the information that would be necessary first of all just to produce one gene capable of of generating a whole new form of a whole new protein but it also illustrates the bigger problem of getting lots and lots of new genes from there's lots and lots of new proteins to build a whole new animal so next slide so the in 1966 when they had this conference at the Wistar Institute it was not yet known whether the mutation selection mechanism could really do the job because there was something else we needed to know we didn't know in effect how rare the combination was in my lock example there's only one possible combination for opening the lock when you link together the amino acids that make up proteins it turns out there's a lot of different combinations that will fold into functional proteins but there's a lot more that won't so we need to know the ratio there in order to get a really solid estimate of how hard this random search problem is so in other words for every one of those nicely folded structure that will represent a protein fold how many of these amino acid combinations are there that don't okay so that was the key question that was not well-known in 1966 the biologists at the time said hey maybe functional proteins are really common maybe the in effect there's lots of combinations on the lock that will open the that will open the dials but the the mathematical scientists especially the computer guys were very skeptical of that because because the reason bike locks work the reason information can be convey'd is that you're eliminating possibilities all the time and so as you have lots of characters in in oscoda script there's gonna inevitably the exponential possibilities are going to mount and the code that the functional sequence seems they thought to necessarily require a lot of gibberish that you don't use so anyway this was unknown though in 1966 next slide now a colleague of mine Douglas axe decided to investigate this very rigorously for 13 was 13 14 years at Cambridge University at a Caltech PhD in chemical engineering but his PhD thesis at Caltech had a protein science molecular biology application so after his PhD he went to Cambridge he worked for 14 years on this crucial question how common or rare are the functional sequences among all the possible amino acid combinations you could ask the same question of the DNA sequence because the DNA sequence makes the protein sequence so are the sequences that are functional are they rare or are they common if they're common you can imagine the Darwinian mechanism working pretty well because you get a random change and you skip from one functional form to another pretty easily but if they're rare or if they're exponentially rare you can search and searched and searched and searched and searched and searched and never find them or you'll be you know like you're the Jim Carrey illustration last night ok so anyway this was Doug took this on next slide and in 2004 he published a fantastic research paper that was a result of several previous research papers in the Journal of molecular biology with a very definitive that with his results which was it was a very definitive quantitative estimate of the rarity of functional genes and proteins and what's called combinatorial sequence base and the conclusion that he reached was that for every functional fold of a fairly modest length he was working with a protein system of about 150 amino acids long most proteins are on average about 300 amino acids in length so there's a modest length protein for every functional protein there are there are 10 to the 77 other possible ways of a meaning of arranging amino acids that won't produce a functional a functional fold and so that means that if the mutation selection mechanism is searching it's good Search Search Search Search Search well wait a minute there's something else we need we need to know isn't there and that still we didn't know how many opportunities does that mechanism have to work all right and it turns out you can estimate that as well next slide you have to do that you need to know how many organisms there have been on planet earth because mutation events can occur when there's what's called a replication event when an organism reproduces or copies itself that's when you could have the DNA's the the the the arrangements of characters in the DNA code randomly change to produce perhaps a new peptide sequence or amino acid sequence that could form a new protein well it turns out there's there's been about 10 to the 40th organisms 10 to the 40th power that's a lot of organisms on planet Earth next slide but 10 to the 40th that would represent the number of trials to randomly change the the DNA in hopes of getting a new protein but that number pales in comparison to 10 to the 77 if you remember you're how to divide exponents you remember you subtract right so this this is equivalent this the the the the the measure of the difficulty of the search is that for every even if even if here's what how we say this if every replication event in the history of life from the beginning of the origin of life till now have been dedicated to searching for a new functional gene capable of building a new functional protein it would only get to search one over ten to the thirty seventh of the possibilities so we were talking a minute ago about searching for one thing out of 10 to the 4 or 10 to the 10th now the the the the portion of the search space that gets to be searched and this is taking into account the whole history of life is only 1 out of 10 to the 37th power or 110 trillion trillion trillionth of the space gets searched change the metaphor just a little bit from bike locks to needle and haystack got a massive haystack the size of Texas we've hidden one needle in it and we're gonna say that that massive haystack so that one needle it represents 110 trillion trillion trillionth of the size of the haystack now you ask yourself is it more likely that the person searching at random is going to find it or not find it well it becomes overwhelmingly more likely that a random search will fail because so such a small portion of the search space can be searched in the time available to get the reasoning okay so we find that to the protean case you know 10 to the 40 there's a lot of organism does there were a lot of replication events but the search space is so vastly in excess it's so much vastly bigger than that that still only a tiny tiny fraction will get searched and so it's still it's overwhelmingly more likely than not that the mutation selection mechanism will fail in generating even one gene capable of producing one new protein in the entire history of life on earth that's what we're up against with the mutation selection mechanism as a means of generating new information it's not an adequate mechanism and that's increasingly recognized the the recognition of this started in the 60s but the work of Doug axe and four or five other independent ways of investigating this question of the rarity of genes and proteins in sequence space have confirmed that the these the functional sequences are far too rare to be found by a random search method even with the role of natural selection preserving the the the the random thing if it happens to be functional is it it's just so unlikely that you would ever find anything functional there's nothing for natural selection to preserve okay all right so that's the information problem next slide how're we doing on time okay now another arguably even deeper problem is the problem that's known as the origin of developmental gene regulatory networks or the origin of genetic circuitry I've only been talking about the problem of getting one gene capable of building one new protein but to build whole new animal forms there is a coordination a choreography that is just breathtaking at the genetic level and this has been mapped out next slide please bye wonderful scientists who only recently died his name is Eric Davidson at Caltech the number of colleagues have worked with him on this but what he found is that is that it's not just to build a new organism cells go through multiple divisions start with the fertilized egg you divide into two into four and the eight and the 16 and at certain point those cells start to differentiate from each other some become muscle cells some become bone cells and become skin and each each of those different types of cells Express different genetic information for building different dedicated proteins and it's beautifully choreographed but in order for that to happen there has to be communication and you need what are called gene regulatory networks and these regulatory networks are genes that control the timing and expression of other genetic information so the right proteins are turned on at the right time as the cells are going through those those divisions and as Davidson and his colleagues mapped this out they would invariably come up with with diagrams like this what does that look like to say any engineers in the auditorium so look it's an integrated circuit and from a standpoint of information flow not electricity flow that's exactly what it is and so the way these things work is you'd have a gene that is not building proteins but it's coordinating everything else so it would express a gene product might be a protein actually or it could be a regulatory RNA and then that would turn on another part of the genome which would in turn turn on another building another gene product which would either turn off or turn on another part of the genome and so you'd get this complex choreography of the right things being expressed at the right time so the cells have exactly the right proteins they need as they begin to differentiate themselves from other cells as bone and and muscle skin and and and other things are being built as the animal is being constructed to the process of development fascinating okay cool really cool science but it also had a profound implication for evolutionary theory because what Davidson and his colleagues found was that these gene regulatory networks are are indeed they have a property that other integrated circuits have it's a rule in engineering that the more functionally integrated a system the more difficult it is to perturb any part of the system without defect to the whole you know you pull out the spark plugs of the the car doesn't work ok so integrated functioning integrated systems are highly sensitive to perturbation to change in their in any of their subsystems and the and and this system was no different what they found is these developmental gene regulatory networks in in their core elements could not be could not be altered even a little bit without shutting down animal development when animal development would shut down the organism would die and no more evolution could even possibly occur at that point so this was the rub you need gene regulatory networks to build new forms of animal life new animal body plants you've got an animal body plan here it's got its own gene regulatory network so you want to evolve one animal body plan into another that's the Darwinian story but that means you've got to move you got to change one developmental gene regulatory network into another type of gene regulatory network but that's the very thing we've discovered in the laboratory never happens and so Davidson who is no friend of theism creationism intelligent design anything like that just has called neo-darwinism a catastrophic error in thinking that the mechanism simply cannot account for this type of complexity and the need to transform one integrated complexity one integrated system of gene regulation into another ok this is a fundamental problem and you know like Jim's talk in the last hour how would people address this in evolutionary theory they really haven't they're just are not good proposals for solving this problem out there ok third problem next let's go next slide and this is in some ways perhaps the big the most fundamental and this is actually when I quoted the two guys Stuart Newman and GERD Muller this is one of the things that really has bothered them about neo-darwinism in their writing and this is the need for what's called epigenetic information we've been talking about all the important information in DNA but there are it turns out that DNA is necessary the information in DNA is necessary but not nearly sufficient to build a whole new animal form in that in just that picture of the cell that doctor tour showed with the carbohydrates and all the information that they have they're involved in intracellular signaling and that's really critical information to animal development as well and there are many many sources of information both in cells and in organisms as they're developing that are crucial to animal development only some of that's in the DNA so next slide let's get a kind of a sense of this so if I want to build a little you know a little fish here there's gonna be lots of new types of cells and organs that are gonna be needed those are gonna require new proteins and we're gonna need new DNA but the DNA information is only sufficient for building the proteins DNA turns out to be necessary but not sufficient for building higher levels of biological form and structure so here's an analogy next slide this is another information-rich hierarchy we've got a a laptop computer so we can now with the technology known as CAD cam we can we can use information to build single components of an electrical circuit so we take the flow of information we build maybe the capacitors and the resistors and the transistors mechanically using information that's encoded in this computer assisted manufacturer manufacturing process but that those parts do not a circuit board make nor does the circuit board make the personal computer what's critical to make that circuit boards you got to get all the parts arranged in the right way okay and that requires higher levels of in sembly instructions and then likewise to get the circuit board into a full the computer you've got to have a lot of other parts you get up switches and and cords and all kinds of wires and you gotta have the chassis and you got the keyboard and all of those parts require assembly instructions as well so the information for build the low-level parts does not suffice to build the whole high-level system and the same exact thing is true in biology DNA codes provides information for building proteins but that information alone is not sufficient to build the higher-level structures and now what that means for evolutionary theory is really profound because the mute the mutation selection mechanism is operating at the lowest level of that biological hierarchy if we can just go back one slide to look at that again we look at the DNA we the the whole idea of the neo-darwinism is you get changes in the DNA strand and the nucleotide sequence and that's going to give you a new protein but that means that in the best of cases even if you can overcome the long odds that we've just been describing to find one of those new proteins in that vast combinatorial sequence space you're still not going to get to build new cell types organs tissues or body plans because you need higher-level instructions other sources of information in my book Darwin's doubt I talked about some of those other sources that are known there's a situs skeletal arrays there's the distribution of membrane targets there's a sugar code there's intracellular signaling and we know more and more about some of those other sources of information that are necessary to build full animal body plans and yet there's a lot of research to be done on this we know there's a lot more out there other sources of information this sometimes it's called epigenetic information or ontogenetic information the point is we know that this additional information is necessary it's not stored in the DNA and that means you could mutate the DNA til the cows come home or indefinitely over billions of years and you will never get beyond generating a new protein even if you can solve those probabilistic problems I was just talking about this is a really fundamental problem and it's leading a lot of evolutionary biologists to say we need a new theory ok now next slide let's let's let's bring this home many people have proposed new evolutionary theories so I don't want to only critique neo-darwinism because in some way that B is critiquing a straw man James Shapiro was the leader in this Third Way was looking for new theories of evolution his is called the one he prefer is called natural genetic engineering he says criticism of neo-darwinism is so early 90s now that word also hasn't gotten into the textbooks affair apparently or into the popular culture but in Darwin's doubt I'm sensitive to the fact that there are many new theories of evolution that have been proposed and many of them have some real advantages over Standard neo-darwinism but what I found in researching these is that none of them actually solve the crucial information problem professor Shapiro's model is a good illustration of this he talks about the processes whereby it's evident that there is sort of a built-in adaptive capacity that if you put an organism under an environmental stress it will trigger the expression of genetic information that was not being expressed before in order to allow the organism to respond to that stress and so this is a kind of evolutionary change the organism is expressing new information but the information was already there it was it just wasn't being it wasn't being expressed that the environmental change triggered it but it didn't explain its origin and as I've looked at each of these different models of evolutionary theory you don't have to go to the book to find out about all of them that the same problem occurs that they tend to they invariably presuppose unexplained sources of information or they just don't talk about the problem of the origin of genetic and epigenetic information that is necessary to build new animal form so my estimation and this is the case I make in the book is that evolutionary theory has really reached an impasse with respect to this foundational question of how you build new form how do you build new animals how do you generate how would the evolutionary process generate new information there are not adequate explanations of that next slide on the other hand oh yeah at this Royal Society meeting that was called by the Third Way people Susan missourah being one of them after afterwards summed up she said the meeting was was characterized by a lack of momentous the problem was really well characterized but there were no real fundamental solutions offered so where do we go then are we stuck well this is where I think the theory of intelligent design when you think about something like the model of natural genetic engineering you're talking about a system with pre-programmed adaptive capacity what's that sound like where does programming come from where does information come from in our experience next slide my argument has been that well that we have an experiential basis for answering that question you may recall from the interview last night I talked about my my time in Cambridge investigating the method of historical scientific reasoning and Darwin's method was was you know really instructive to me because what he was what he was doing was he was trying to reconstruct what happened in the remote past he was trying to identify the cause of the origin of new forms of life and he built his ideas about historical scientific reasoning from the work of on the work of Charles Lyell the famous geologist and John Lyle had a maxim he said that when we're trying to explain events in the remote past we should be looking for causes that are now in operation causes now in operation can I see the next slide is there something one more okay well you have to go back to this is a truncated version of the slides we had this little hiccup with the technology so I'll just do this without out slide for a minute I just want to explain that the the scientific rationale for the theory of intelligent design or the positive case for intelligent design so I'm studying the historical scientific reasoning and I come across Lyle and he says that that the job of the historical scientist is to find causes that are now in operation causes that produce the effect in question that we've seen in operation around us so for example when I was an undergraduate I studied or science and I was in Eastern Washington out in Eastern Washington they have this wonderful Palouse country with the rolling hills where they grow wheat but there's still little patches there of white powdery stuff left over from this event a few years ago and if you're a if you're a geologist and you go there and you find these white powdery patches and you didn't know about the explosion of Mount st. Helens you might wonder what weary what are these how did these how did these get here what caused these to get here so using Darwin's method you generate a lot of possible hypotheses you say maybe it was a maybe was an earthquake maybe it was a maybe was a flood maybe it was a big storm maybe it's a volcanic eruption of those four which is the best explanation using Lyle's criterion of a cause now in operation a cause that we have seen in our uniform and repeated experience producing the effect in question flood earthquake is the volcanic eruption because we've seen volcanoes produce white powdery stuff floods and storms don't usually do that okay so our knowledge our uniform and repeated experience of cause-and-effect relationships in the present enables us to reconstruct the causal history of events in the past that was the whole method that Darwin and Lyell developed Darwin called it looking for a very causa a true cause a cause known to produce the effect in question and as I got thinking about this I realized wait a minute this applies to the whole question of the origin of information where where does information come from in our experience where do we get programmed adaptive capacity or just a program well we get it from minds from intelligence and in fact whenever we see information and we trace it back to its source we're talking about a hieroglyphic inscription or a radio signal that has information embedded in it or a paragraph in a book or I would even argue when these origin of life researchers are following these complex recipes and building these molecules and sequencing them just the way they want and extracting the the reaction products and purifying things what they're doing in on the you know just basic accidents of information theory anytime you exclude one option and elect another anytime you say I want a zero not a one or an a not a T you're imparting a bit of information so the to the extent of these simulation experiments have modeled the origin of life or modeled chemistry that's least moving in that direction they're actually inadvertently modeling the need for intelligence to move the experiments in that direction so they're confirming this basic principle that information comes from an intelligent source and so when I was thinking about that I came across passage in a book on applying information theory to to biology to molecular biology and the information theorist Henry Cuellar said the the creation of new information is habitually associated with conscious activity a lightbulb went on for me that's the lie Elian dictum repeatedly associated as or that's our uniformly repeated experience that's what we use to infer causes in the past so what we know if information always comes from an intelligent source and there's information at the foundation of life and if new information is necessary to generate new forms of life new animal life and we know that the materialistic processes are not sufficient to do that we have a really strong grounds for inferring intelligent design is the best explanation for the origin of the information necessary yes to build the first life but also to build to construct the Cambrian explosion or to turn that around I would say that the Cambrian explosion with its informational requirements is best explained by the theory of intelligent design and I wouldn't stop there but I do want you to see on the previous slide how our critics have responded to this argument if we go back just one this is Charles Marshall I was I've never been more thrilled to have a negative review in my life this was written in science 2013 he reviewed Darwin's doubt it was a very respectful review he liked some things about it but he was also very critical of the fundamental thesis and he said Myers case depends upon the claim that the origin of new animal animal body plans requires vast amounts of novel genetic information in fact he says our present understanding of morphogenesis that just means body plan building indicates that new the new animals were not made by new genes but largely emerged through the rewiring of gene regulatory networks what oh gee no regulatory networks made of genes containing genetic information so in order to explain the origin of information he just invokes a prior unexplained source of information the information in the gene regulatory networks and he says that the evolutionary process somehow rewired those networks of genetic information which would have required multiple native changes in code which would have been another source of unexplained genetic information so you I think this is very instructive because you really don't have to be a PhD in biology to see the nature of this this dialectic that in order to refute the case for intelligent design people have either refused to engage the issue of the origin of genetic information or they have simply presupposed unexplained sources of information which doesn't solve the problem at all and if that's the best that the best can do and charles marshall is really one of the top scientists in the series a terrific scientist i admire his work but i think on this point he's come up sadly short if that's the best the best can do i think the theory of intelligent design is on very strong footing indeed thank you very much [Music]

Channel: Discovery Science

Views: 159,766

Keywords: science, philosophy, biology, evolution, Darwinism, neo-Darwinism, human origins, science and faith, intelligent design, Discovery Institute, Charles Darwin, biologic institute, icons of evolution, darwin's doubt, Stephen Meyer, Jonathan Wells, Douglas, Axe, Evolution News & Views, Michael Behe, William Dembski, John West, Jay W. Richards, Darwin Day in America, Darwin's Black Box, Privileged Planet, science and religion

Id: L0-hgSjnomA

Length: 65min 12sec (3912 seconds)

Published: Mon Mar 18 2019