I have to make this post because I’m getting bored of seeing the same tropes circle around in the pro-ID community. The two I have in mind here are two extremely grandiose and unsupported conclusions that ID proponents appear to have hallucinated from some articles that simply don’t support them.
1. Attempts to construct the minimal cell is not relevant to understanding the origin of life.
The first I have in mind is the idea that it has somehow been shown that a form of life simpler than a cell with 256 genes could not exist. This idea is apparently derived from the Craig Venter institute’s work on trying to design what they call “the minimal cell”, or “the cell with the minimal genome”.
I keep running into creationists and ID proponents propagating the falsehood that this is thought, intended, or implied to represent the first form of life to come into existence at the origin of life, or an attempt to make the simplest possible form of life.
It is not, and that idea is not supported anywhere in ANY of the references. It is not found in the introduction, or in the discussion, or in the conclusion in any of the references given in support of the claim. It is not in any popular press articles, and to my knowledge have not been stated anywhere in a presentation by any of the scientists working on those projects.
It is a fantasy entirely dreamt up by creationists and ID proponents. It appears to be what ID proponents want the results to imply. But that is all it is, a want inside the privacy of their heads. And once it comes out in the real world, it fails to make contact with any putative supporting evidence.
2. Experiments on fruit fly development do not even remotely imply that the gene regulatory networks that establish basic body plans could not have evolved.
Another trope that rears it’s ugly head here and there is the idea that basic body patterning genes, such as those that control bilateral symmetry, could not have evolved. This one seems to be based on various experiments done on fruit flies. Some where scientists have tried to select for things like asymmetry and failed to produce any are then interpreted by creationists to mean the symmetrical body patterning could not have evolved in the first place.
And even worse is where scientists have simply been using experiments designed to look for essential genes, and thus deliberately put mutations into genes to deactivate them, the idea being that if the mutation causes lethality, the deactivated gene must have been essential.
These results are then taken to by creationists to simultaneously imply both that basic body plan patterning could not evolve in the first place, and that any and all mutations in these only lead to death. As with the previous trope, none of these are of course implied by any of these experiments, nor stated in any of the publications on them, nor believed or supported by any of the authors of those experiments. Because it simply doesn’t follow nor is it even weakly indicated.
These tropes have been debunked probably hundreds of times on the internet, and yet they keep circulating apparently completely uncritically in the ID community, some times even finding their ways to people who ostensibly claim to not be creationists or ID proponents (such as James Tour). And yet they’re demonstrably false.
Dear ID proponents and creationists who post here, please stop propagating these historical and scientific falsehoods. If you see others within your community who regurgitate them, you should tell them to stop. They’re myths.
If one looks in the original publications (e.g., Hutchison et al. 2016, Nüsslein-Volhard and Wieschaus 1980) for statements like “this lower threshold of functionally essential genes disproves abiogenesis” or “these results disprove the macroevolution of animal form via mutations in regulatory elements,” then of course no such statements occur.
But data and experiments underdetermine their interpretation. Example: the Michaelson-Morley experiment, set up to detect the existence of the luminiferous ether: Michelson–Morley experiment - Wikipedia The negative results of the experiment were later interpreted by Einstein within the context of the theory of special relativity. Einstein wrote, in 1905:
…unsuccessful attempts to discover any motion of the earth relatively to the “light medium,” suggest that the phenomena of electrodynamics as well as of mechanics possess no properties corresponding to the idea of absolute rest.
Michaelson and Morley had no idea that Einstein’s theoretical shift of perspective, dropping an absolute rest frame of reference, lay right around the corner. Yet that’s just my point: experiments underdetermine their interpretation.
So a design theorist could look at “synthetic cell” experiments, such as Syn 3.0, and infer that any viable cell (given reasonable assumptions about available nutrients, environment, and so forth) will have a discoverable lower threshold of essential molecular components (proteins, large RNAs, lipids, etc). Does this disprove bottom-up theories of chemical evolution and abiogenesis? Not at all – that requires the further assumption that ALL cells will face similar functional demands.
One can deny that further assumption, as you do, with an existentially-quantified claim (“some cell, currently unknown, is simpler”) resting on your conviction that the bottom-up, chemistry-first path to life actually happened. OK, then show how, starting with chemistry, the lower threshold can be breached.
The reason the lower threshold looks pretty strong isn’t the particular set of components (proteins and RNAs, lipids and carbohydrates) in question. Rather, it’s the set of essential functions – metabolism, information storage and transfer, selective transport across the cell boundary, reproduction, and so on – that any free-living entity must perform. “All living things,” writes Stuart Kauffman, “seem to have a minimal complexity below which it is impossible to go” (1995, p. 42).
Parallel case: controlled heavier-than-air flight in an atmosphere like Earth’s requires (1) lift, (2) thrust, (3) three-axis control (pitch, roll, yaw). These are functions, and can be instantiated by any variety of suitable materials. Arguably the major breakthrough of the Wright brothers was to find out how to perform (3) without killing themselves. Now, as noted, one can get (1), (2), and (3) with wood, fabric, aluminum, carbon composites, propellers, jet engines, you name it – but if you want to take off a heavier-than-air craft, move it directionally with yourself aboard to a destination (hot air balloons go where the wind takes them), and land, without killing yourself, you need lift, thrust, and three-axis control.
That is a major error in inference. Perhaps a design theorist would make this inference, but no biologist who understands the problem would make that inference. It relies on a large equivocation.
And this is exactly the problem, you have an assumption that doesn’t lead to the conclusion you are trying to argue for. In a way the inference is based on having a particular restrictive definition of life.
If you’re going to say that for something to quality as life, it must be essentially like a modern cell in that it must have a metabolism and be able to biosynthesize all it’s own components, have a nucleic acid or another organic polymer-based genome, and be able to self-replicate by genetically regulated enzymatic reactions, then whatever simpler version we can come up with that could lead to such a thing, you can just insist isn’t life.
But have you then succeeded in arguing that the origin of life must happen “all at once”, as if we must go from a dilute soup simple organic molecules and jump straight to that cellular stage? Not at all.
If a cell can’t biosynthesize it’s own components, is it then not a form of life? Suppose given your definition of life you say no, have you then successfully argued that life has to “start” at the fully-formed-cell-stage? No, all you’ve done is argued what you think qualifies as life (or a “minimal cell”), you have done nothing to argue that life starting is difficult or unlikely. Nor have you done any work to show that there could not be something simpler, still cell-like, that you just wouldn’t call a cell.
You have done no work to show that the stage you envision as qualifying for the category of life can not have got to there through a history of gradual increase in complexity.
The inference fails already at the level of reason. It simply doesn’t follow that because you decide to define life as having to possess these different qualities or components, that there could not be a gradual progression to that stage.
I’m not denying that assumption out of any prior convictions about how life must have come into existence. I am simply not joining you in making it, because I see no good reason to. And in fact I see good reasons not to.
No, I actually don’t have to do that. I only need to point out that your assumptions are unwarranted, and do not lead to the conclusion you are seeking to establish.
Let us recall that ID proponents are seeking to argue that life must have originated by some sort of intelligent design, because the “simplest” form of life we can imagine is apparently still way too complex to have just sort of arisen out of the “soup”. That’s basically the argument. That even with as little as 200 or just 100 genes, the probability of having such a polymer just assemble itself correctly, combine with lipids, protein enzymes and so on is so unlikely as to be outside of serious consideration.
Supposedly life is too complex even in it’s simplest form (ID proponents point to Craig Venter’s minimal cell here), and to believe that such a complex thing “just happened” is so ridiculous you might as well believe in magic, so the only other option is a kind of intelligent design. That’s essentially the argument. The conclusion you are seeking to establish is that life must have been intelligently designed, because it’s too complex to be rationally believed it could happen all at once.
But the crucial problem with this argument is that it ignores the possibility of a gradual process. That work on the minimal cell does not at all indicate that such a gradual process is unlikely or impossible.
This is where you try to invoke some arguments against the plausibility, or possibility of the gradual process. You might say, for example, that if we imagine that life was even simpler in the past in some way, it will be lacking one of those crucial functions. If it lacks this function, it isn’t alive.
I think you see the problem now. So what if that isn’t alive by your criterion? You have done no work to show there was not or could not be such a stage. A simpler stage you just won’t call “life” or a “minimal cell”. A stage in which some sort of entity did not replicate itself, but was replicated by some external cycle(in the same way, for example, a fluctuating temperature cycle does in PCR some of the work that a host of enzymes do in cells as we know them).
Where it’s “essential” components like the cell-membrane (composed perhaps of fatty acids or other simple amphiphiles) weren’t synthesized by it’s own genetically encoded enzymes, but by geochemistry, where growth and division was not regulated and catalyzed by genes and enzymes, but by driven again by some environmental factors.
To get any further with your argument now, you’re going to have to start making either bare assertions, or arguments from ignorance. You’re going to start having to declare, despite not actually knowing, that such a stage could not exist. Or ask seemingly rhetorically, how could such a thing that lacked component X persist? Or, how could it evolve into a cell?
Well, that’s why it’s called research into the origin of life. The whole point is to try to find out what and how that could be.
And we haven’t even looked at the actual evidence for life having been simpler in the past(you know, that phylogenetic thing ID proponents always try to handwave away).
But your point in the OP was that it’s unreasonable to interpret data in any way other than supporting a naturalistic premise. There I do disagree. “Bottom-up, chemistry-first” OOL research is predicated on the assumption that such a pathway actually existed. I think the evidence fails to support that assumption; the difference in our two cases is (a) you assume naturalism, and (b) I don’t. The difference is philosophical, not scientific (although it has consequences for what research problems one thinks worth pursuing).
This paper (below) is relevant. CAVEAT: I am NOT claiming that the authors support ID. They don’t.
Can you expand on your thoughts on that paper? It’s an interesting paper, and certainly relevant, but I fail to see how it could be interpreted in support of your case. If anything, passages like one seem to undermine it:
Presumably, early‐earth life forms originated through an accumulation of changes of ever increasing complexity, resulting eventually in photosynthetic prokaryotes. In this sense, extant assembly‐pathways almost certainly echo their own evolutionary history, that is, a protein is guided to its cellular destination along a route that was established at an earlier time and subsequently fortified by other, similarly developed, interdependent cellular processes. Supporting evidence for this conclusion is provided by a recent mass‐spectroscopy study of the conservation and formation of the quaternary structure of protein homomers.37 This study confirmed that structure alone is sufficient to infer both the evolutionary and physical path of subunit assembly, an example of “ontogeny recapitulates phylogeny” at the cellular level.
That’s a rather strange reading of my post. First of all it’s not true that was the point of my OP. Second, I find it odd that you appear to be contrasting ID with naturalism, unless you think all forms of intelligent design are by definition supernatural. Third, the actual point was that it is unreasonable to interpret the data (in this case work towards synthesizing the “minimal cell”) as making the gradualistic origin of life appear unlikely, and thus to require ID.
You seem to have a hard time distinguishing a claim that only X types of explanations are allowed, from the claim that the data does not support Y-type explanations. I am doing the latter.
I am trying to explain that it is a misconception going around in ID circles, that work towards constructing a “minimal cell” has implications for the origin of life. And by implications I mean the conclusion ID proponents are usually extracting from estimations for the minimal genome, that because the “minimal genome” still has hundreds of genes, such a thing is too unlikely to have originated without involvement by an Intelligent Designer.
I tried to expand on some of the reasons why it is a misconception in my response to you.
If you define life to be something like the minimal cell with your mentioned functions, then you’ve made it the challenge before the origin of life field to find an explanation for how such a thing came to exist.
Here my crucial point is that merely saying that something simpler than this wouldn’t be alive (because it couldn’t self-replicate, for example), isn’t actually saying something about the plausibility or probability of the origin of life. All you’ve done is made a statement about where you draw the line between life and non-life. You have not said anything about what kinds off processes could lead to life. Hence the conclusions ID proponents are seeking to draw, that ID is the only plausible explanation for the origin of life, are totally misguided. That conclusion is not even weakly implied.
One problem here is that the prototypical ID argument based on this kind of “minimal genome” or “minimal cell” work is never actually rigorously spelled out. If you were to try to construct a proper syllogism that ends with the conclusion that ID is required to explain the origin of life, you’d need to have one or more premises in that argument that assert it is extremely unlikely or impossible that there is a gradualistic process leading to the first life. I have yet to see any such argument that wasn’t basically arguments from ignorance, or blind assertions.
Yes. And the only way to find out if that is true is to do the research. But it’s actually not just an assumption.
There really is some evidence for simpler stages in the early history of life. Not much, but it is there and can’t just be ignored. Hints from phylogenetics of a simpler time, before cells had evolved the biosynthetic pathways for making their own amino acids.
Inferences of ancestral nodes in the phylogenetic trees of the oldest (most widely conserved) protein sequences increasingly mirror the abiotic distribution of amino acids produced by nonbiological chemical reactions, as we go further and further back in time. That’s evidence right there that the earliest proteins were synthesized from amino acids that existed in the environment, and that the biosynthetic pathways for their synthesis subsequently evolved. The “modern” distribution of amino acids we see in extant proteins drops off the further back we go, and larger and more complex amino acids like Tryptophan become less frequent, while the simpler amino acids like glycine, alanine, valine and so on become more and more frequent. This trend converges on the same distribution expected from chemical thermodynamic calculations of the ease of their synthesis, the distribution observed in various carbonaceous chondrites, and mirrors the distribution also seen in various experiments in abiotic organic chemistry, such as simulated hydrothermal conditions, spark-discharge experiments and so on.
See:
Higgs PG, Pudritz RE. A thermodynamic basis for prebiotic amino acid synthesis and the nature of the first genetic code. Astrobiology. 2009 Jun;9(5):483-90.
DOI: 10.1089/ast.2008.0280
Brooks DJ, Fresco JR, Lesk AM, Singh M. Evolution of amino acid frequencies in proteins over deep time: inferred order of introduction of amino acids into the genetic code. Mol Biol Evol. 2002 Oct;19(10):1645-55. DOI: 10.1093/oxfordjournals.molbev.a003988
Jordan IK, Kondrashov FA, Adzhubei IA, Wolf YI, Koonin EV, Kondrashov AS,
Sunyaev S. A universal trend of amino acid gain and loss in protein evolution. Nature. 2005 Feb 10;433(7026):633-8. Epub 2005 Jan 19. Erratum in: Nature. 2005
May 26;435(7041):528. DOI: 10.1038/nature03306
This evidence also fits well with the evidence for the length of pathways of biosynthesis for the individual amino acids(and hence their order of evolution and incorporation into the genetic code), which imply a gradual evolutionary history of the extant genetic code and translation system. It fits together, and a gradual evolutionary history of life from simpler stages explains the existence of these patterns in the sequences of shared similar genes in a way no sensible ID theory can.
Of course, there are other good reasons for making such an assumption that also don’t have to do with any prior commitments to “naturalism”. For example that in science we generally prefer simpler and more likely explanations to more complex and unlikely ones. That’s a heuristic for sorting among candidate explanations and testing them, not some sort of inviolable adherence to a preconceived conclusion.
There isn’t a whole lot of evidence for it, but it’s false to say there is none. Of course, there is actually zero evidence for the assumption that life was intelligently designed.
And to make matters worse, there is no model of intelligent design to test. Heck, we can’t even evaluate the probability of intelligent design at all. It doesn’t make sense for ID proponents to say that a physical and chemical origin of life is so unlikely as to be outside of rational consideration so ID mustadunit, because if you’re going to say that you prefer the more likely over the less likely, you’re going to need to say how you know how likely the preferred explanation is. What is the probability of ID? What is your number?
With respect to you saying I assume naturalism, that’s actually false. But in contrast to me, you actually do make an assumption about the origin of life. You’re a Christian and you think God created life. Yet you can show no actual scientific evidence in support of it.
With respect to your last point I agree, if you assume God created life and that there can be no gradual pathway to the “minimal cell”, then you’re going to think origin of life research isn’t worth pursuing. But as I argued above, that’s an assumption you’re making and it’s not at all supported by work on the so-called “minimal cell”.
If questions concerning the origin of life are beyond what we can know from the evidence we have, then we have no evidence that it was intelligently designed.
Either we have such evidence or we do not. To say we have such evidence is to say we have some model or hypothesis which, if true, makes that data more likely or expected. But such a model does not exist, hence none of the data we have can be said to constitute evidence for it. Even if we charitably stipulate that such a model will be made in the future, and that with this model in hand some of the data we already have will be shown to be more likely, and/or better explained, the fact is we are not in that situation right now. So no matter how you put it, there is no evidence we have that life was intelligently designed.
The strongest claim you can really make at the moment is that we know next to nothing about what occurred at the origin of life. There is a little bit of evidence of life having been even simpler than current work towards constructing the minimal cell have succeeded at. But besides that we know almost nothing.
This is something I’ve really wanted to discuss. The ID argument that mutations in development can’t cause the evolution of new body plans because those mutations are always early in development and those early mutations are lethal. I’ve tried starting threads elsewhere on it but they never took off. So any informative input is appreciated
There is no one in the office over the weekend, but on Monday, I can ask one of the Discovery Institute media staffers to post the pdf of one of my lectures on this topic (e.g., the relative severity of body plan-affecting developmental mutations), which is loaded with references and illustrations from the evo-devo literature. You can tell me which references you would like, and I can email them, or, if open access, link to them here.
An enormous literature exists on this question, going back into the late 19th century, and the work of people like William Bateson and Hugo de Vries in the first decades of the 20th c… In the 1920s and 30s – e.g., in the writings of key neo-Darwinian theoreticians such as Ronald Fisher – macromutations were rejected as an evolutionary mechanism largely because such mutations required early developmental expression (in animals), were highly pleiotropic, and hence, overwhelmingly deleterious. A persistent theme then developed in evolutionary theorizing, which can be seen as a destructive dilemma (i.e., where either choice in the dilemma brings negative consequences): advocates of macromutation, such as Richard Goldschmidt (1878-1958), argued that gradual changes would not construct major features of organisms, whereas the mainstream, represented by Fisher or Dobzhansky, argued that macromutations would be inevitably deleterious. This dilemma comes right up to the present, in current evo-devo discussions.
Anyway, I’ll have Discovery give me a URL for the lecture pdf on Monday, and will post the link here. Then you can tell me what references you would like for further investigation.
In this case the classic issue of creationists ignoring that back when these developmental pathways first evolved, all the surrounding and related molecular and cellular interactions used to be different too. Many genetic interactions that later evolved on top of early developmental processes, often times did not even exist back when those early developmental processes themselves first evolved.
This problem undermines so much creationist thinking. We can see the same problem with the concept of irreducible complexity. The flagellum couldn’t have evolved because if you remove component X, the flagellum would stop working. But back when component X evolved the remaining components had other roles. The protein amino acid sequences were different in many ways. Since that time they have undergone both substitutions, deletions, insertions etc. etc. Sure if you take the modern counterpart and remove some component, the system might break down and stop performing some crucial function. But you have not actually recreated the ancestral state just by picking some particular thing out of a larger whole and knocking it out. You now have to retrace the evolutionary history of all the surrounding components it interacts with, each of which have accumulated many changes since that time, and change those too to the corresponding ancestral state. The only way to do that is to do comparative genetics and ancestor reconstruction.
Basically all creationist thinking about evolution ignores phylogeny. You don’t disprove that we evolved from worms by our not being able to survive with our arms and legs cut off.
Humans can survive with their arms and legs cut off (or missing). Many people do.
Seriously, Rum – wait for the pdf (sorry but I don’t have the capability, here in Chicago, of being able to archive pdfs on the secure server in Seattle). The problems I will describe arise within evolutionary theory itself – there’s hardly a “creationist” in sight in the entire lecture (which discusses phylogeny at length). If I could represent the situation in a Venn diagram, there would be an enormous region of overlap – most of their respective circles, in fact – between textbook evolutionary theory and ID. Go to an ID research meeting, and, if you’re an evolutionary biologist, you’ll feel right at home, except maybe for the occasional hymn singing on Sunday morning.
Not independently in the wild, which is obviously what Rum was referring to. The analogy applies just as well to organs like the heart or brain. The fact that us humans can’t live with our brain or heart cut out tells us nothing about the possibility of evolving from creatures that lacked both these organs.
It’s worse than that for this tired trope. You note that the trope must ignore or bypass thought about early evolution. It also correspondingly features old thought itself (cf. refs to Bateson, de Vries, Fisher) that necessarily occurred in the absence of detailed knowledge of genetics–specifically for one thing, knowledge of genetic control systems. This matters a lot IMO, because one of the biggest implications of regulatory evolution, central to evo-devo, is that pleiotropic effects of body-plan-altering polymorphisms can be (and are) avoided by tissue specificity.
So the argument about “macromutations” being bad bad bad has to dance between erasing the context of early evolution and erasing the knowledge of subsequent regulatory evolution. Robust conversations about the evolution of morphological novelty are happening right now, and by listening to them, one can immediately see the emptiness of this trope while heartily endorsing the importance and level of interest in the question.
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swamidass
(S. Joshua Swamidass)
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