[00:00:04] Speaker A: ID the Future, a podcast about evolution and intelligent design.
[00:00:12] Speaker B: Welcome to id the future. I'm your host, Steve Dilley, and I'm pleased today to welcome Dr. Casey Luskin. Casey, great to have you on the program.
[00:00:24] Speaker A: Thanks for having me on, Steve. And you better call me Casey. Only my wife is allowed to call me doctor. No, actually, that's not even true. Nobody, I don't like being called doctor. I find it very know you call me Casey every other day of the week. So let's just go with our normal routine here.
[00:00:40] Speaker B: That sounds great. Of course, listeners to id the future know about you, that you've been an interviewer and an expert on the program many, many times. But for those who may be new, Casey holds a PhD in geology from the University of Johannesburg and bachelor's and master's degrees in earth sciences from the University of California, San Diego, and a JD also from the University of California, San Diego. He's currently the associate director of the center for Science and Culture at Discovery Institute. And in that capacity, we work closely together.
Casey, today I want to chat with you a little bit about a paper that you co authored, peer reviewed paper that you published last summer in the journal religions. It's titled on the relationship between design and evolution.
And the paper gives an extended analysis of a really formidable and interesting book, the compatibility of evolution and design, which is written by a University of Helsinki theologian, rope Kajonin.
And listeners should know we'll provide a link to Casey's paper in the description of this episode. Listeners may also know that we've done a series on Kajonin's book at id of the future, as well as posts on evolution news.
So we're continuing that today. Thanks for joining, Casey.
[00:02:24] Speaker A: Yeah. And it's also your paper, Steve. You were the lead author and did a fantastic job of taking the lead and writing that paper and helping us to put all of our thoughts together into one document. And we're really happy with how it turned out. So thank you for.
[00:02:39] Speaker B: Yeah, great. Yeah, it was a fun project for all of us.
For those who may be just joining this series, Casey, tell us, give us a brief overview of the compatibility of evolution and design. What is Kajonin up to in the book?
[00:02:58] Speaker A: Yeah. So what rope Kajonin wants to do is he wants to argue that evolution and design are compatible at very deep fundamental levels and that even that design can help us, or I should say evolution can help us make an argument for design. It's a very, very interesting thesis, and it grabbed our attention because it was kind of a novel way of looking at things. And some folks might think, well, it doesn't sound like it's that hard to really marry or merge evolution and design into a single model. Because, for example, you could have things that are changing over time. And in that sense, they're evolving, and yet they're designed. And we see this all the time. There's the famous example of the Corvette. Where you see the models of the Corvette changing through the years. It's evolving in the sense that it is changing over time. But, of course, all that evolution is being driven. By the actions of intelligence agents. Who are designing and building new models of the Corvette as the years go on. So, in one sense, it's not that hard to merge evolution and design. But what rope Kajon wants to argue. Is that you can actually marry evolution and design. At very deep, fundamental levels. When it comes to the origin and evolution of life. So he would argue that mainstream evolutionary biology. And everything that basically mainstream biology. Would say about the origin and evolution of life. Is fundamentally correct. That it has been nothing but blind and mechanistic material causes. All the way down back to essentially the beginning of the universe. But yet he would say that we can also make a robust case for design. And so this is sort of a novel thesis, again, that grabbed our attention. We thought it might be something that a lot of folks who call themselves theistic evolutionists. Would probably find attractive. And we wanted to ask, is this actually a successful merger of evolution and design? Does he actually make a case that works? And just to sort of give a sneak peek at the punchline, what we found is that it might be possible to live in a universe that rope Kajonin predicts. Where, basically, the universe is designed from the very beginning. To allow for evolution to work. There's sort of all this front loaded information. Built into the laws of nature, the laws of the universe, the initial conditions of the universe, to allow evolution to unfold in a totally sort of blind and unguided, in the sense that it operates on its own. Without any external guidance whatsoever. And so, basically, the universe just does its thing, and all of life evolves through natural mechanisms. You could potentially create a universe like that. But when we look at where Kajonin says. That we're supposed to find evidence. For the universe being designed so that evolution can work, we don't see that the universe is actually designed in that way. The universe does not appear to be designed in a way that rope Kajonin proposes to allow evolution to work. And we'll get into this in more detail. So ultimately, we basically said that his argument fails on the facts. And also we found that if his argument was valid, it actually would do harm to our ability to detect design. I'm sure we'll get into that, too.
[00:06:04] Speaker B: Yeah, that sounds great. And thank you for that overview, Casey. Obviously, the paper itself is pretty involved. It's a very long treatment, 25,000 words or so. And you were intimately involved in the whole thing and in particular sections.
Particular subarguments used to evaluate Rope's thesis.
Take us through some of the particular sections that you were really closely involved with in the paper, really the whole thing, but were the lead thinker in some particular areas.
[00:06:43] Speaker A: Yeah, and maybe I could tell a little bit of the background here also of how we got involved with this. I mean, I've known Rope Kajonin and his work for a number of years. I would say I think very highly of his work, even though I don't always agree with what he's arguing. He is a very careful and thoughtful thinker, and I found that he often will. For example, when he describes intelligent design, he's very careful to make sure that he's representing it accurately, even if he doesn't fully agree with, say, folks like Behe or Demsky or Meyer. He's very careful in trying to make sure that he describes id accurately. And he often also will respond to critics of intelligent design in a way that I would know. I often agree with him, and he says, no, look, whether or not he agrees with intelligent design, he'll say, this is not a very good objection to intelligent design, and he'll do a good job of responding to those objections. So I've often found rope, aka Jonan's work, his papers, his books, to be very thoughtful and carefully argued. His book, the compatibility of evolution design was no exception to that. So when this book came out, I thought, I think that we, as a team at discovery, should go through the book very carefully, do a book club, and that's what we did back in 2022, which led to this paper. So I guess in a way, like, having known of his work for a while and thought highly of rope Kajonin's work, I wanted us to look at this carefully. It sort of came from out of that, that this paper came from. But when it came to actually writing the paper, yeah, I mean, certainly was involved with all, I think all of us who co authored the paper, you, me, Brian Miller, Emily Reeves, we were all involved with the whole thing, but certainly did a lot of dialoguing. With you about the framing. What did we actually think about his argument? The biggest section I probably worked on was the material on the bacterial flagellum. Also helped Brian Miller with the protein evolution section. That was largely his brainchild. But I helped a lot with the writing of that, and then worked with you on a lot of the material on design detection. And in fact, I think that one sort of, if I contributed one thing to the section on design detection, it was that I really felt like that if his view of design fails, that actually has negative implications for the plausibility of mainstream evolution and the reason why. And we'll get into this, I'm sure. But what's really interesting about rope Kajonin's thesis is he basically says that, look, all other things being equal, a mainstream evolutionary account or a mainstream evolutionary mechanism is not usually going to work very well to build the kind of complexity of life that we see on earth. And he says that actually, for evolution to work, you need fine tuning. You need design to be built into the laws of nature to sort of give evolution a boost so that, say, one protein sequence can be able to evolve into another protein sequence without getting stuck in some non functional stage of a fitness valley, something like that, in a fitness landscape where it can't traverse from one point to another. So he says that the fitness landscapes of protein sequence space have to be fine tuned to allow for evolution to work in order to basically give evolution that helping hand it needs. But without that helping hand, without that sort of serendipitous fine tuning that he says we see in our universe, evolution is not going to work. So he sort of acknowledged that evolution is going to have a tough time. All other things being equal, evolution is going to have a tough time to do the job that it's got to do. But so what we found is that, okay, well, if the fine tuning that Professor Kajonin says evolution needs in order to work isn't there, then that actually has implications for whether evolution works in our universe. And of course, we argued that we don't see that fine tuning, but again, I'm sure we'll get into that, too.
[00:10:23] Speaker B: Yeah, that is fascinating. He's essentially said, if I understand his argument correctly, that evolution requires a very specific kind of preconditions, fine tuning. And part of your work in the paper, Casey, shows that there is no such preconditions or fine tuning. And that would, of course, have negative implications, accepting Kajonin's very framing of whether or not mainstream evolution would succeed. So, yeah, let's we'll circle back to that. That's, I think, just an excellent insight on your part.
One of the sections you mentioned that you really put a lot of time and thought in is a section on the bacterial flagellum. So let's tunnel in on that a little bit. So start us off just in a basic way. First, what is the bacterioflagellum?
[00:11:14] Speaker A: Yes, so the bacterial flagellum is a very famous molecular machine, which exists in many prokaryotic organisms to help them to essentially swim through a liquid medium to be able to find food. And it kind of looks like an outboard motor. It's this whip like appendage that spins around, propelling it through, again, some kind of a water based medium, to be able to find food. And the flagellum, of course, has become an icon of intelligent design, sort of the paradigm of irreducible complexity. The idea, coined by Michael Behe, that there are many features of biology which require a certain core number of parts in order for them to function. And if any of those parts are missing or don't work right, then that system is not going to be able to function. So essentially, he calls them irreducibly complex, because you cannot reduce their complexity without them ceasing to function. And the argument has been made that the bacterial flagellum is irreducibly complex. And, of course, some folks will say, well, there is no one single bacterial flagellum. There's many different variations of flagella out there in biology, and there is some truth to that. There are great variety within the world of prokaryotes, of different flagella. But actually, there was a paper a number of years ago in Nature reviews microbiology, which found that all flagella have a certain sort of core set of parts that seem to be indispensable, and also that they have certain core subsystems which seem to always be there. You've got to have the motor, you've got to have the anchor, you've got to have the chemotaxis system, you've got to have the appendix that spins around. So even if different bacteria, different types of prokaryotes, have slightly different variants on their flagella, there is sort of a core set of parts that have to be there for the flagellum to work. And you do find those parts pretty universally around different flagella.
[00:13:09] Speaker B: So, I mean, in general, it sounds like the bacterial flagellum counts as evidence for design.
And, of course, kajonin is championing a model of designed evolution, you could say, in which he accepts full blown mainstream evolution. And if that's the case, why has he discussed the philagellum? It would seem like it may pose a problem, at least initially, for his theory. Why discuss it at all? Why is it in the book?
[00:13:43] Speaker A: Yeah. So the standard rejoinder to Michael Behe's arguments for irreducible complexity is that maybe the flagellum didn't start off as a molecular machine that helps bacteria swim through.
Or maybe the parts of the flagellum did not start off as being part of a molecular machine that helps bacteria to swim and find food. Maybe they started off having other functions in biological systems and they were co opted, or there was a process of what's called exaptation, where basically parts are borrowed, tweaked, changed and retooled to perform entirely new functions in different systems. And so all the parts of the flagellum, according to the way many evolutionarists will try to explain the origin of the flagellum, initially they were doing other things in other systems, they were borrowed, co opted, and then they were retooled to be able to suddenly perform some new function in the flagellum. And so this kind of a model fundamentally depends on the ability of proteins to be radically retooled and reshaped to do totally new kinds of functions. And in our protein section of this paper, we saw that with rope cajonin. He actually tackles the evolution of proteins. And he talks about some of the research of idea theorists like Douglas Axe, who have found that functional protein sequences are actually very, very rare. And he argues, well, actually that's not a problem for evolution, because even if protein sequences are rare, you might be able to have fine tuning of protein sequence space, so you can evolve from one protein sequence to another through sequence space, remaining functional at each small mutational step of that evolutionary pathway. And it's because essentially the fitness landscapes and protein sequence space is finely tuned to allow for these very narrow bridges through sequence space that allow you to remain functional from one protein sequence that's functional to another. So this essentially shows that the fitness landscapes of protein sequence space have been set up by God, have been fine tuned, he argues, by God, to allow for new types of proteins to evolve. And he says that this same kind of fine tuning would allow for the co option of flagellar proteins, okay, that you could take some flagellar filament protein that's originally doing something totally different in a biological system, and you could tweak it and mutate it from whatever its initial function was until it's now being able to be co opted to be able to function in the flagellum. And what he actually recognizes, it's a very interesting argument, Steve. He actually recognizes that for some kind of a co option account of the origin of the flagellum to work, it's going to be requiring a lot of what he calls serendipity. He says, quote, there is indeed quite a bit of serendipity in parts useful for one purpose, being so easily adaptable to another role, he says. It seems, then, that defending the power of evolutionary mechanisms requires assuming that the landscape of possible biological forms has some fairly serendipitous properties. And he says the ability of evolution to generate teleology appears to depend on teleology. So what he's basically saying is that to have these preconditions, these smooth fitness landscapes, to basically connect up very different, very totally unique and different structures within biological universe, this requires sort of a serendipitous fitness landscape that will allow these things to be able to evolve. And this shows that teleology was built, or design was built into the fitness landscapes of the biological universe. And so essentially is saying that under many universes, an idea, a model like cooption, is not going to work, but we happen to live in a universe that has been finely tuned to allow biological parts to be co opted very easily, to be able to then build new complex features like a bacterial flagellum. So essentially, our universe has been rigged to allow these things to evolve, even though normally they would be very difficult to evolve.
[00:18:00] Speaker B: Right. Yeah, thanks. That's helpful. So, to summarize on Kajonin's view, God created the laws of nature, and the laws of nature are such that they give rise to conditions that make evolution possible, including the formation of new proteins by selection and mutation.
And with the formation of new proteins, you can ultimately build protein machines. You can take something like a type three system and over time, cobble together a bacterial flagellum. So the universe is set up to allow for evolution to occur. And then I think he also says, when you get something like the bacterial flagellum, that does actually count as evidence for design.
It seems, on his view, that something like that would be too sophisticated to come about by chance, say, chance processes or in a naturalistic universe.
So he thinks the bacterial flagellum counts for design, but just in an evolved way.
[00:19:08] Speaker A: That's exactly right, Steve. He sees design in the flagellum. In fact, he says that Behee's argument for irreducible complexity, quote, could simply reveal the extent to which fine tuning is required by evolution. So he says, look, irreducible complexity, it's there.
It's a very robust case for design. It's a very elegant system. This shows even more to the extent that evolution requires fine tuning in order for it to work, because it has to have fine tuning. The universe has to be very specially set up in order for evolution to be able to work to build these complex features. So it's a very interesting argument.
[00:19:47] Speaker B: So this is interesting then, because so much of his case for design here hinges on fine tuning in a very particular way, so that you get proteins evolving to others, so that you get the emergence of protein machines.
So when it comes to the flagellum in particular, take us through that. Casey, what makes you think that Kajonin's case for design is suspect here when it comes to how design is supposed to come about, on his view, via evolutionary processes?
[00:20:24] Speaker A: Yeah. So he has to be able to make a case that the flagellum actually can evolve in our universe, that we see that there is design in the fitness landscapes of protein sequence space, and we see that the flagellum reflects its evolutionary history. And so what he relies upon, essentially, is what many folks have relied upon when they've argued that the flagellum could arise through these co option adaptation type models. And basically it comes down to what is called protein homology, where he argues that because two proteins are similar to each other, therefore, that shows that they share some evolutionary history, and this is evidence that the system evolved. And he basically makes a very standard kind of evolutionary argument for the evolution of the flagellum. Well, there's a number of problems with citing homology of flagellar proteins to argue that the flagellum evolved. Number one, you can't say that sequence similarity really what this homology means is it just means that flagellar proteins have similar amino acid sequences to other proteins out there in the quote, unquote, biological universe. The first problem, though, and Michael Behe talks about this in his books, that we shouldn't confuse sequence similarity with evidence for a step by step evolutionary know. You need to be able to demonstrate an evolutionary pathway, and sequence similarity alone does not show that. And then when we talk about whether or not flagellar proteins actually are homologous, he cites a couple of sources to claim that about 90% of the parts of the flagellum are similar or homologous to other parts in biology. So we went through his sources and sort of the citations and the arguments that they made very carefully and found that really, when you look at the data, it's not the case that 90% of flagellar proteins show homology to other systems. It's really, at best, only four out of the 42 proteins that were cited in these sources. So that's about 10% are homologous, to quote, similar parts in other systems, as he puts it, and could have potentially served as precursors to the flagellum. Quite a few of the proteins belong to another molecular machine called the type three secretory system, and this has often been cited as an evolutionary precursor to the flagellum. In fact, Kajonin calls it a potential precursor to the flagellum. But there are a number of reasons why the type three secretory system could not be an evolutionary precursor to the flagellum. For one, bacterial flagella are found very widespread among many different kinds of bacteria. And so it's sort of according, if you look at it from an evolutionary standpoint, that suggests that flagella go very deep in the evolutionary phylogeny. They rose very early in the history of bacteria because they're widespread among many types of bacteria. The type three secretory system, in contrast, is only found in a very narrow range of bacteria, and that suggests it's a much later innovation and that its genes are much younger than bacterial flagellum. So a number of folks have actually argued that rather than the type three secretory system being a precursor to the flagellum, it's probably more likely the other way around, that flagella have to be older than the type three secretory system. And if they are related, the flagellum is a precursor. And also, we have to consider, what is the type three Secretory system used to do? It's used by certain bacteria that actually predate upon eukaryotic cells. Okay, well, eukaryotes arose much, very late in the history of life, compared to when bacteria first arose. And flagella are used by all kinds of bacteria that don't predate upon bacteria to be able to swim around and find food. So it seems like the type three circuitry system is something that arose much later in the history of life. So the bottom line is that what Ropekajonin wants to argue, that we see all this sequence homology between flagellar proteins and parts in other systems. This shows that they could have been co opted. This shows that the flagellum evolved. We just don't see the vast majority of that sequence homology. And when it does show up, we don't see it in systems that look like they could have been evolutionary precursors. To the flagellum. So we just don't see this sort of this fitness landscape, this evolutionary pathway that led to the flagellum that Kajonin predicts had to have been there.
[00:24:54] Speaker B: So this sounds mean, I suppose a listener could say, hey, wait a minute, it sounds like you're criticizing Kajonin's view of evolution, about how, in evolutionary history, the bacteria of flagellum evolved.
But, of course, Kajonin takes evolution as a given, mainstream evolutionary theory as a given, and from that basis, tries to harmonize that view with intelligent design in biology. So bring it home here for the listener. What does your analysis of Kajonin's case have to do with criticizing his view of design, his version of design itself, or of his version of design and its harmony with evolutionary theory?
[00:25:42] Speaker A: Yeah, that's exactly right. I mean, our critique aims at Kajonin's view of design. He thinks that the laws of nature and fitness landscapes and so on, that they're fine tuned to allow for random mutation and blind selection to evolve proteins and molecular machines that are made out of these proteins. And that's why he talks about the bacterial flagellum. But we argue in the paper, and we show in the paper, that we don't see this design, this fine tuning of the laws of nature to allow for these proteins and molecular machines to be able to evolve. And really, the meat of this argument goes back to the section on protein evolution in the paper, where we say that we do not see that fitness landscapes of sequence space are finely tuned to allow for one protein sequence to be able to evolve into a very different kind of protein. And that then extends into his arguments for the flagellum. We don't see that proteins are co optible, because we don't see that proteins are easy to evolve. So when we see careful analysis of these fitness landscapes, the proteins and these molecular machines that are made of proteins, they showed that the kind of design that Professor Cajonin has in mind for our universe simply doesn't exist. And the empirical data basically run counter to his conception of design. And so we would argue that if his conception of design fails, if it's not what we find in the real world and the universe we live in, then his attempt to put design and evolution together likewise has problems. So that's why we get into this. But we also had to address along the way, some of his specific claims that the philagellum 90% of its proteins show homology. He's making those claims. It's part of his case that the universe is designed to make evolution work, and we had to look at those very carefully to show that it didn't work. Yeah.
[00:27:29] Speaker B: So in one sense, you're just correcting errors, biological errors, about a certain percentage of homologous parts and so on. And in another sense, you're taking his particular conception of design seriously on its own terms, and asking, are there these fine tuned preconditions? Do proteins come about in the way that he says they do? Are landscape, fitness landscapes smooth? Which would all be crucial to his conception of how a design like the bacteria philagellum came about.
Okay, that's helpful. So that is really aimed at his understanding of design itself. Sort of stepping back a little bit.
As you mentioned, the bacteriophagellum has been around for a long time. Michael Behe made it famous. Does Behee's big picture intelligent design now? Does Behee's classic argument for the bacteria philagellum still hold up? Is it still good evidence of design, obviously, in a different way than Kajonin has in mind, we would argue?
[00:28:38] Speaker A: Definitely, yes. I have yet to see a stepwise evolutionary account of the bacterial flagellum. Instead, you see these very vague appeals to cooption. And what is the evidence for cooption? Well, it almost essentially always comes down to sequence similarity, protein homology between flagella proteins and other proteins that are out there. And I'm sorry, but that does not make for a stepwise evolutionary pathway. And even the sequence homology that we see is often quite suspect. When you look at it closely, it really does not hold up on closer scrutiny to give you any clues about how the flagella might have evolved. So, yes, I do think Beh's arguments still hold up.
[00:29:17] Speaker B: One final question.
As you mentioned earlier on this episode, Cajonin argues that evolution, even mainstream evolution on its own, is impotent. On its own. It can't produce biological complexity, it can't produce flora and fauna, and that it needs design, it needs designed preconditions, smooth fitness landscapes and so on. And you've argued, in the case of the bacteria flagellum, in the case of proteins, that there are no design preconditions in the way that Kajonin specifies.
What does this imply for his model? What does this imply for mainstream evolutionary theory? I think you had a really profound insight there. Take us through it.
[00:30:00] Speaker A: Well, thanks, Steve. I don't think I have profound insights very often. So it's good to hear that I had one here. I think what was going on as we read through rope Kajonin's book, the Compatibility of Evolution. Design is, we would see these comments where he would essentially say, look, evolution is going to require a lot of serendipity or fine tuning in order for it to work. So essentially what he was acknowledging is that all other things being equal and an unguided evolutionary mechanism, random mutation, natural selection, et cetera, is going to struggle to produce a lot of the complexity that we see in life. And so that's why he argues that our universe needs design. It needs this fine tuning in order for evolution to be able to work and get the job done to build the complexity of life. But the implication of that is that, all other things being equal, evolution is actually not a very good mechanism without design, without this helping hand from the design that comes in the form of the fine tuning of the universe and the laws of nature, without that helping hand, evolution is not going to work. And so there's sort of this implicit part of his argument that evolution is going to struggle to produce the complexity of life. So if this design that he proposes has to be there to help evolution to work, if that design isn't there, then that has huge implications for the validity of evolutionary theory in our universe. And we would argue that actually we don't see evidence for that fine tuning and that that therefore has really profound implications for the overall, I guess, efficacy of evolution to produce the complexity of life. If this helping hand isn't there, then evolution is in trouble. And that's sort of the way that we left it at the end of our paper. We're not trying to critique evolution generally, but he sort of put evolution on the chopping block here by saying it needs this design in order to work. But then when we find that that design that he's looking for isn't there, that actually means that evolution isn't going to work. And some other kind of design, not evolutionary design, maybe some other form of design is needed to explain what we see.
[00:32:11] Speaker B: Thank you, Casey. That is really well put. Thank you for being on the program. Great to chat with you.
For our listeners, please note that this is just one episode in our ongoing examination of Kajonin's book, the compatibility of evolution and design.
And do note that we also have an ongoing series on the same topic at evolution news, and that Casey's co authored paper, a link to it, will be in the description of this episode.
Once again, I'm Steve Dilley with idthefuture, and thanks for listening.
[00:32:51] Speaker A: Visit
[email protected] and intelligent. ##design org. This program is copyright discovery institute and recorded by its center for Science and Culture.
