Recently, I was browsing through the latest posts over at Evolution News and Views, and an anonymous article titled, Imagine: 60 Million Proteins in One Cell Working Together, caught my eye. By now, most readers at TSZ will be aware that I consider it overwhelmingly likely that the first living thing was designed. However, I’m also highly critical of attempts to over-egg the case for intelligent design. The article I read was one such attempt: it contained some unfortunate errors and omissions.
The author tried to bolster his case by quoting from two articles in the same issues of Nature (volume 537, 15 September 2016): one by Aebersold & Mann, and the other by Huang, Boyken, and Baker. As it turned out, neither paper was about the origin of life: one was about the proteome (or the set of all the proteins in a cell), while the other discussed de novo protein design.
How many proteins are there in a single cell? And how many are needed?
The ENV article was titled, Imagine: 60 Million Proteins in One Cell Working Together. When I first saw that headline, I was a little puzzled. When I hear the phrase, “60 million proteins,” I automatically assume the speaker means different kinds of proteins. But what the author actually meant was: 60 million protein molecules inside a single cell.
“What kind of cell?” you may ask. Apparently the figure of 60 million is taken from a passage in the Nature article by Aebersold & Mann, where the authors are relating some astonishing facts about the proteins in a tiny yeast cell:
A proliferating Schizosaccharomyces pombe cell contains about 60 million protein molecules, which have abundances that range from a few copies to 1.1 million copies per expressed gene.
However, yeast cells are eukaryotic: they have a nucleus. The first living thing didn’t: it was prokaryotic, and it would have been much smaller than a yeast cell. How much smaller? We don’t know. But it turns out that the number of protein molecules in a tiny cell belonging to the bacterium Mycoplasma pneumoniae is only 0.05×106, or just 50,000. That’s three orders of magnitude less than the yeast cell described by Aebersold & Mann.
But the real question we need to ask is: how many different kinds of proteins are there in a simple bacterial cell? It turns out that a typical bacterium requires 4,000 proteins for growth and reproduction, while humans require more than 100,000 different kinds of proteins. Some bacteria, however, need far fewer than 4,000 proteins, according to MicrobeWiki:
In 1995, the entire genome of M. genitalium was sequenced in less than 6 months using the random shotgun sequencing technique. It was found to have the smallest known genome of any free-living organism at about 580 kilobase pairs long, with 479 coding sequences for proteins. For comparison M. pneumoniae has 677 protein coding sequences, H. influenzae has 1703, and E. coli K-12 has 4,288.
382 of the 482 protein-coding genes in Mycoplasma genitalium have since been identified as essential. Dr. Stephen Meyer, in his work, Signature in the Cell (New York: HarperOne, 2009), generously estimates (ibid., p. 213) that a minimally complex cell needs 250 different kinds of proteins. Dr. Michael W. W. Adams, in an article titled, The Influence of Environment and Metabolic Capacity on the Size of a Microrganism, makes a similar estimate: in a nutrient-rich environment, a life-form with a minimal biosynthetic capacity would require at least 250 genes.
So the first cellular life-form probably required 250 different kinds of proteins, in order to function. That’s still a pretty impressive number.
What proportion of amino acid sequences are functional?
The Evolution News and Views article refers to the recent article by Huang, Boyken, and Baker, before going on to cite the pioneering work of Intelligent Design researcher, Dr. Douglas Axe:
This paper is interesting because it relates to the work of Douglas Axe that resulted in a paper in the Journal of Molecular Biology in 2004. Axe answered questions about this paper earlier this year, and also mentioned it in his recent book Undeniable (p. 54). In the paper, Axe estimated the prevalence of sequences that could fold into a functional shape by random combinations. It was already known that the functional space was a small fraction of sequence space, but Axe put a number on it based on his experience with random changes to an enzyme. He estimated that one in 1074 sequences of 150 amino acids could fold and thereby perform some function — any function.
I’ll return to Dr. Axe’s estimate in a moment. The Evolution News and Views article went on to breathlessly declare that Axe’s figure of 1 in 1074 had actually been too generous, and that the true proportion of 150-aa sequences capable of performing a biological function was hundreds of orders of magnitude smaller (green bolding below is mine – VJT):
The new paper in Nature seems to point to a much smaller functional space. The authors say,
It is useful to begin by considering the fraction of protein sequence space that is occupied by naturally occurring proteins (Fig. 1a). The number of distinct sequences that are possible for a protein of typical length is 20200 sequences (because each of the protein’s 200 residues can be one of 20 amino acids), and the number of distinct proteins that are produced by extant organisms is on the order of 1012. Evidently, evolution has explored only a tiny region of the sequence space that is accessible to proteins.…
Since 20200 is about 10260, and the space actually sampled by living organisms is 1012, the numbers differ by at least 240 orders of magnitude for proteins of length 200, or about 183 orders of magnitude the 150-amino-acid chains Axe used. No wonder the authors say that “the natural evolutionary process has sampled only an infinitesimal subset” of sequence space.
This, I have to say, is a complete misreading of the paper in Nature by Huang, Boyken, and Baker. The authors are not trying to answer the question explored by Axe – namely, what proportion of 200-amino acid sequences are capable of performing a useful biological function? Rather, what they are estimating is the proportion of possible 200-amino acid sequences which are found in nature. Their answer is: 1012 divided by 20200 (which is approximately 10260), or in other words, 1 in 10248. But instead of concluding that any amino acid sequences which are not found in nature are non-functional, as the writer of the Evolution News and Views article appears to do, they draw the opposite conclusion: “The huge space that is unlikely to be sampled during evolution is the arena for de novo protein design.” In other words, there are a whole lot of new proteins out there which nature hasn’t created yet, but which scientists can create.
Back to Dr. Axe’s estimate of the proportion of 150-amino acid sequences which are capable of performing a biological function: I have previously discussed his figure of 1 in 1074 in my online review of his latest book, Undeniable: How Biology Confirms Our Intuition That Life Is Designed (New York: HarperOne, 2016). I quoted from various professors, including an expert in protein structure who argued that the proteins in the first living things would have all contained considerably less than 100 amino acids:
So I think the counterargument to the ID folks is not that sequence populations of 10E80 needed to be searched to find a 100-mer with robust enzyme activity, but rather that random populations of a few million relatively small proteins could contain a few molecules from which to start the evolutionary process.
Another professor whom I cited regarded Dr. Axe’s work as highly biased, because he had based his studies and calculations on very large sequences of amino acids (150-amino acid chains), even though much shorter sequences (such as polypeptides) were known to have biological functions.
Additionally, I quoted from a third professor, who kindly pointed out to me that because a very large number of different amino acid sequences were capable of performing the same biological function, the actual number of attempts that would be required to make a molecule with the same function as one of these proteins was likely to be much lower than 1060 or 1080. This professor also estimated that the number of attempts that would have been available to evolution had been estimated at 1042 – far greater than the number of attempts that could be made by doing man-made experiments (no more than 1012, which means that any protein which is too difficult for human experiments to generate might still be created by natural processes). This professor added that that while he was very sympathetic towards arguments against the natural origins of the first cell, and while he thought Dr. Axe may well be correct in arguing that abiogenesis was astronomically unlikely, in his opinion, Dr. Axe seemed to be trying to calculate the probability of an unknown process, and was therefore overstating his case.
Bottom line: we don’t really know how rare functional 150-amino-acid proteins are in sequence space, and we don’t know that they couldn’t have been derived from shorter proteins.
How did life get to be left-handed?
The Evolution News and Views article went on to say that there were
Axe’s estimate of one in 1074, one must note, referred to mutations to existing proteins in the universal proteome of all organisms. When considering random chains of amino acids in a primordial soup, however, Steve Meyer noted in Signature in the Cell (pp. 210-212) two other requirements. The amino acids must be one-handed, and they must form only peptide bonds. Applying generous probabilities of 0.5 for handedness and 0.5 for peptide bonds, Meyer reduced the probability for a lucky functional protein chain of 150 amino acids to one in 10164, far beyond the universal probability bound (p. 212). [Green bolding mine – VJT.]
The problem of life’s one-handedness which Dr. Meyer raises in his book is a genuine one: without homochirality, life would not exist.
A recent article by Denise Henry in Phys.org, titled, Discovery demystifies origin of life chirality phenomenon (March 11, 2015) describes a promising breakthrough in the field:
University of Akron A. Schulman Professor of Polymer Science Tianbo Liu has discovered that Mother Nature’s clear bias toward certain amino acids and sugars and against others isn’t accidental.
Liu explains that all life molecules are paired as left-handed and right-handed structures. In scientific terms, the phenomenon is called chirality…
Liu found that any molecules, if large enough (several nanometers) and with an electrical charge, will seek their own type with which to form large assemblies. This “self-recognition” of left-handed and right-handed molecule pairs is featured in the March 10, 2015, issue of Nature Communications.
“We show that homochirality, or the manner in which molecules select other like molecules to form larger assemblies, may not be as mysterious as we imagined,” Liu says.
In their paper, Liu et al. summarized their results as follows:
In summary, chiral macroanions demonstrate chiral recognition behaviour by forming homogeneous blackberry structure via long-range electrostatic interactions between the individual enantiomers in their racemic mixture solutions. Adding chiral co-anions suppresses the self-assembly of one enantiomer while maintaining the assembly of the other one. This leads to a natural chiral selection and chiral amplification process, indicating that some environmental preferences can lead to a complete chiral selection. The fact that the relatively simple inorganic macroions exhibit chiral recognition and selection during their assembly process indicates that the related features of biomacromolecules might be due to their macroionic nature via long-range electrostatic interactions
Another, more recent paper in Chemistry World by Dr. Rachel Brazil, titled, The origin of homochirality provides an excellent overview of the work in the field done to date, and discusses new findings. Dr. Brazil puts forward her own hypothesis.
Readers may still be wondering: why are the amino acids in a protein linked by peptide bonds, instead of non-peptide bonds? I’d like to invite any biologists who may be reading this post to weigh in on this subject.
What the ENV article got right
The Evolution News and Views article redeems itself at the very end, when quoting from the paper by Huang, Boyken, and Baker. The authors state:
Despite the advances in technology of the past 100 years, human-made machines cannot compete with the precision of function of proteins at the nanoscale and they cannot be produced by self-assembly.
The authors go on to suggest that the extreme efficiency of these nanoscale proteins is the due to the fact that “selective pressure operated on randomly arising variants of primordial proteins, and there were also hundreds of millions of years in which to get it right.” But this is pure speculation. As the author of the ENV article aptly puts it:
Now ponder that. They are duly impressed by the intricate molecular machines that proteins make in the cell, yet their worldview does not allow them to consider this as evidence for design.
Indeed.
What I am arguing in this post is that while I see no reason in principle why nature cannot generate proteins capable of performing useful biological functions, and while the mathematical arguments against such proteins originating by natural processes strike me as inconclusive, it seems to me perfectly reasonable to ask why the proteins we observe in nature are capable of technical feats which even our best scientists cannot match. It is not enough to simply invoke “hundreds of millions of years”: this is lazy scientific thinking, which makes no testable predictions. In the absence of such predictions, intelligent design of these nano-machines by a super-intellect sounds like a plausible explanation which warrants consideration.
Here’s one questions I’d like to ask the biologists: do the most efficient nanoscale molecular machines tend to be relatively short (as we’d expect if they arose naturally) or relatively long?
Readers who would like to know more about the difficulties attending abiogenesis are welcome to view Dr. James Tour’s online talk, “The Origin of Life – An Inside Story,” here or here. The take-home message of Dr. Tour’s talk was that currently, scientists know nothing about how the ingredients of life originated, let alone life itself. Dr. Tour makes no attempt to “sell” intelligent design to his audience: indeed, he formulates his argument without even mentioning it. Readers will find it highly watchable.
Do you think that evolutionary theory is a good explanation for the phenomena it purports to explain, or not?
Good that you notice. My point is that Darwinism intrudes into metaphysics. Just look how handily evolutionary assumptions swept over all sciences and gave rise to “cognitive” theories, social Darwinism and the like.
No, not good at all.
I have no idea what you’re talking about here. It looks as if you are conflating evolutionary explanations of cognition and thought with the politically motivated use of evolutionary explanations to support certain policy choices.
You do realize that those are different things, right?
And why is that? How did you arrive at that conclusion? What alternative scientific explanations would you prefer to evolutionary explanations?
I know the difference, but social Darwinists don’t. You see the connection, don’t you? The connection is “survival of the fittest”.
Scientific ones. Logically sound ones.
If biologists respected evidence half as much as linguists, common descent would not have been proposed. Common origin of all languages has not been proposed. There’s even no common origin to writing.
Did Gregory just change his name to “Erik”?
Can you be at all specific?
Yep, pretty much.
I have been quite specific. Re-read and re-think what’s been said about the analogy of biology and linguistics, the analogy that Darwin himself raised.
Biologists have no evidence for common descent and no reason to posit the primacy of matter. Darwin posited those things without giving any other reason than asserting that that would be “natural” and “the only possible arrangement”. Every next generation of biologists has swallowed these suppositions entirely without giving it a thought what they are doing.
Linguists, on the other hand, go by evidence. Yes, a single tree collecting all languages would look nice in the eyes of some, but since there is no evidence for it, the textbooks honestly say so and we have terms like related versus unrelated, language family versus language isolate.
KN, are you still of the opinion that admins here have nothing to do with the tone and atmosphere of the site? Doesn’t the force of evidence matter at all? Then you are a man of unfounded opinions.
POOF.
Let me see if I understand the argument here.
Are you saying that there’s no evidence for common descent because the analogy between biology and linguistics is weak?
Do you seriously think that the entire case for common descent rests on that one analogy?
I’m going to assume that that’s not your actual view, because that would be an astonishingly stupid claim.
Anyone even slightly acquainted with evolutionary theory would recognize that the underlying logic of Darwin’s thinking about the origins of language was, rather, as follows: there was probably a single original language because of the similarity in patterns between biological and linguistic evolution and because the evidence for common descent in biological evolution is compelling.
I don’t think it’s a particularly strong argument, and while I do think there was probably a single original language, I don’t think Darwin’s analogy gets us there.
But that’s neither here nor there: the point rather is that the evidence for common descent in biological evidence is compelling completely independent of the parallel with language, and also the evidence is pretty compelling that natural selection is one of the mechanisms at work here.
So I will ask one more time, Erik: what reasons do you have for your opinion that evolutionary theory is a bad explanation of biological phenomena?
There is no evidence for common descent. Full stop. Then on to the next point.
The analogy between biology and linguistics is either false or, if right, damaging to pretty much everything Darwinist evolutionary biologists believe.
Its metaphysics is bad. If you deny that there is metaphysics in evolutionary theory, then I can show that you are wrong. Or, you would perhaps say it’s okay to mix metaphysics and science, but surely this is not so when we are dealing with bad metaphysics.
As an explanation of biological phenomena… Well, what are biological phenomena? Life is. Does it explain the origin of life? No. Does it explain the origin of species (incidentally the title of Darwin’s magnum opus)? Sort of. But then you have already said there are no complete explanations, i.e. bad explanations is apparently all we can have. So what are you really asking?
What would evidence for common descent look like?
If humans and chimps share a common ancestor, what should be there that isn’t?
Erik:
Fercrissakes, Erik. Read Theobald:
29+ Evidences for Macroevolution
The Scientific Case for Common Descent
Common descent is not just about humans and chimps. It’s the claim that all life forms come genetically from earlier life forms, eventually from the first.
The evidence for it should be somewhat similar to the evidence for common descent of all languages, if we go by Darwin’s analogy.
The thing is this: Darwinian evolution looks suspiciously similar to Neoplatonic theory of emanation, except that the causality is reversed. Darwinian reversal does not make sense. Matter does not have the capacities attributed to it in Darwinian theory. Spirit or mind has.
So, if you people believe in Darwinian evolution, there’s actually no reason for you to disbelieve the theory of emanation. Because it’s the same theory, only more complete. Theory of emanation bears out the analogy with linguistics all the way.
I think you are misunderstanding “common descent”.
There has long been an argument about whether there is a single descent tree, or a forest of descent trees. The term “common descent” would apply in either case. Many early evolutionists probably thought that there might be a separate tree for each of the major phyla.
That it is all one tree comes mostly from the DNA evidence that connect humans with cabbages.
And yes, common descent is seen in languages. But in that case, it is not a single tree.
Okay, but what exactly are you denying then, the common descent of human and chimp, or the universal common ancestry of all life?
What would that look like in practice? Try to give a testable prediction.
Leaving universal common descent aside for the moment and focusing in on primates, suppose I say to you there’s a hypothesis of the common descent of all primates including humans. What should we expect to find if that is true? Would you say there’s something missing for that hypothesis to be believable and if so, what would that be? What would the missing piece(s) be?
A mechanism that does not involve teleology.
We already have that, it’s called random mutation, natural selection and genetic drift.
It’s not emanation in reverse to think that unguided processes can give rise to more complex organisms from simpler ones.
So the consilience across biogeography, embryology, paleontology, and genetics just doesn’t count for anything? Or inference to the best explanation as a tool of theory-building?
Well, if common ancestry as inference to the best explanation to explain the consilience across multiple lines of evidence isn’t good enough for you, then would would you prefer?
A good deal here depends on whether “bad” here means “false” or “dangerous”.
As to whether there is “metaphysics in evolutionary theory”, this phrase would need to be unpacked a bit.
Every scientific theory has its own ontological commitments: what must be the case in order for the theory to be true. That’s true for evolutionary theory, and it’s also true for classical mechanics, electromagnetism, general relativity, etc.
In those terms, the ontological commitments of evolutionary theory are that there populations of reproducing organisms, those those organisms have hereditable variation, and that not all offspring survive to reproduce.
I take it that none of those are contentious claims?
As to the claim that evolutionary processes are “unguided,” this means neither more nor less than the following: there are no empirically detectable processes that first determine what features will be adaptive in an environment and than cause novel phenotypes containing those features to come about.
It should be stressed that, when understood in those terms, evolutionary theory is fully compatible with most forms of theism.
As for the metaphysical uses and abuses of evolutionary theory, I’ll grant that evolutionary theory has been used to support false metaphysics and dangerous ethics/politics. But so have most scientific theories, so that’s hardly a reason for rejecting it.
I simply deny that an explanation is bad by virtue of being incomplete.
An explanation is bad by comparison with competing explanations that offer greater descriptive precision, yield more accurate predictions, or greater explanatory adequacy by taking into account a wider range of phenomena that the explanations purport to explain.
And thinking that an explanation is a good one grants no immunity to revision or even rejection in light of further evidence or subsequent theoretical innovation, and so is incomplete in the innocent way that all empirical explanations are incomplete.
(All this is rather elementary philosophy of science, by the way.)
Amazing that the argument always goes back to square one.
What is square one, petrushka?
And why is it that you constantly plug Wagner’s book but can never be bothered to start an OP on it? Surely it is an ID killer. Right?
I don’t need to give any more testable predictions than the theory evolution has. If I need to, then we are not being equal and fair.
The theory of evolution says one species evolves into another. Do we observe this in outside world? No. Has this been replicated in labs? No. Etc.
One theory says the processes behave law-like in general, while possible aberrancies are recognized and eliminated in the long run, and that distinctions between species are required, i.e. species tend to be sticky, and when they change/evolve, there must be a critical mass of volition behind it. The volition is either in the individual (as it is in higher life-forms), in the group/species, or in the universal law itself. The other theory says matter acquires life and life-forms acquire cognition and volition without any guiding force, but it’s all law-like for no reason.
Roughly the same predictions, different ultimate cause. This is a point that I won’t let you obfuscate.
We disagree on something rather profound here. You seem to agree with ID-ists that “inference to the best explanation as a tool of theory-building” can be used without any guidance from basic logic. Basic logic as in law of identity and law of non-contradiction. From observing the changeability of matter you think it’s legitimate to posit that matter by itself does the changing and, further, it can change into anything whatsoever, building up consciousness and whatnot. Whereas basic logic dictates that if there is moving, then there is a mover on one hand and the moved on the other.
Yes, but the word “unguided” has nothing in it that would restrict it to the empirical realm, so it’s not true that it means neither more or less than what you make it to mean. What you make it to mean is a highly specialized contextual meaning and I don’t know of an atheist – beginning with Darwin himself – who would think that evolution would be compatible with theism, or with “most forms” of it. They don’t see it your way precisely because they assume it’s “unguided” both empirically and metaphysically.
Evolution is certainly viewed as a direct refutation of Genesis Chapter 1, which is the prevalent theism in the West. And the theory of evolution is also prevalent in the West, so they are in direct competition. Darwin saw it possible to insert God only into areas that pose difficulties to evolution, such as origin of life. Meaning, the main form of theism in the West that is so-to-speak compatible with evolution is God-of-the-gaps.
If we honestly speak of theisms in all diverse forms, then theories of evolution are nothing special. Namely, they are theories of emanation. For example, read Yoga Vasistha which recounts about a hundred creation stories, most of them emanation-like, perhaps only one or two comparable to genesis. In that sense, yeah, evolution is quite compatible with theism, except that, if truly understood to be compatible with theism, there is no room for atheism.
If we go strictly by the actual testable predictions of the theory, then common descent is a fact.
Obviously the reason I’m asking YOU for testable predictions of common descent is that you’re saying there is no evidence for it, which is amazing. That must mean you have a COMPLETELY different idea about what that evidence would actually look like.
I’m taking about the past. If common descent is true for extant orders, such as the primate order, what should we expect to find in these primates that would imply common descent? You seem to say there isn’t any property of primates that implies common descent.
.. Over hundreds of thousands of years. You creationists always leave that out, seemingly on purpose. It would become obvious that once you include it, your demand to see large-scale transitions in the lab becomes an irrational demand that is actually contrary to what the theory says.
We haven’t been around to record change for hundreds of thousands of years. Despite this, we still see divergence and we have cases of insipient speciation in both the wild and lab populations.
Not to mention fossil series such as the evolution of the horse. Or the origin of mammals. Or Birds from Dinosaurs. To pick some well-known examples.
Quite simply, if common descent isn’t true and evolution didn’t happen, these fossil series shouldn’t exist, at all.
Why would you expect to see a hundred thousand year process take place in a laboratory in mere decades? It is irrational to demand as demonstration something the theory says pretty much can’t happen.
It’s as much of a fact as common descent of all languages is. Meaning, it can be pondered as a possibility. But even so it has no direct metaphysical implications that atheists usually take it to have.
I’ve already said about five times what the evidence should look like: Like the evidence in linguistics.
Obviously, this argument cuts both ways on emanation. You cannot replicate, because Very Long Time™ – so your predictions/assumptions are as good as mine by that standard. Except that on emanation you should not be able to replicate this not only because Very Long Time™but also because of the kind of agent that it takes to do it. Basically, you’d need to invoke superhuman demonic forces to be able to do it. Which is why all is well as long as you don’t do it.
Just like, there are ancient/extinct languages, therefore common descent? By the way, common descent in linguistics used to be posited in old times because of the story of tower of Babel: The mixing of languages there meant just splintering the original Hebrew into unintelligible dialects. Are you okay if we take common descent this way? Why not?
Whether it has metaphysical implications is entirely besides the point.
You claimed, quite unambigously, that there was zero evidence for common descent. At all.
I think there’s lots of it. So we must have entirely different ideas about what that evidence would look like. So far you’ve deflected by reference to some vague concept like “the evidence in linguistics”.
What would that look like in biology? Give a concrete example.
And that is so vague as to be pretty much unintelligible. Please give a more direct, concrete example of what you mean.
Use, as an example, the primate order. What should we see IN primates, if they share common descent, which we do NOT see, in your view?
You can do predictive hypothesis testing of past events by comparing the predictions of theory against field-observations.
For example, if a meteor of a certain size struck the Earth in 50.000 bce in some specific location, we should find a crater with a specific set of properties in that location. That’s a hypothesis that makes a prediction about a past event that we can observationally test in the present.
That’s how we can test common descent. Very superficially, If primates share common ancestry, we should expect to find that we can construct from genetic and morphological data, certain nesting patterns. We then go and look at them and see if we can, in fact, construct those predicted nesting genetic and morphological patterns.
If anyone actually, literally made inferences like that, then yes that would be silly. But that is not how the inference of common descent is arrived at.
I’m absolutely fine with that, if that is actually what the evidence shows. I have zero experience or credentials of relevance to linguistics, so I can’t comment on that and I actually don’t really care. The facts are what the facts are, but we are discussing the common descent of cellular life.
You claimed there is zero evidence for it. You’ve yet to even explain in a clear and concise manner what you would actually consider evidence for common descent.
Then you can surely list the best ones. Let me take a look. If you say “primates” then I say this is like saying that since Indo-European languages form a family, therefore all languages are a single family. Does not follow, because there are utterly unrelated languages.
ETA: In terms of biology, this means that I can peacefully concede that primates (humans and apes) are genetically related, but it does not follow that this serves as evidence of common descent for all life-forms. There must be some different evidence.
All (spoken) languages are made up of vowels and consonants, like all cellular life is made up of genes. Does not follow that there’s common descent. Much less does it follow that it evolved by itself unguided.
Agreed.
No. We are discussing Darwin’s analogy.
Here you go.
Obviously. Nobody would claim that because one can make a case for the common descent of all primates, that means all of cellular life shares common descent.
But I didn’t claim that anywhere. I brought up primates because I wanted you to explain what evidence for common descent would look like, taking a specific example (primates).
In other words, what would convince you that all currently existing primates evolved from a common ancestor? What would the evidence for this be like?
Of course not.
The evidence for UNIVERSAL common descent includes additional things besides the evidence for the common descent of primates. Yes. Of course.
I agree, the common descent of all life, or even just primates, does not hinge on the mere existence of genes in the constituent members of the groups. Just like it is not implied that because written languages are made up of letters that doesn’t in itself mean they have a common origin.
You’re stating a lot of completely basic and trivial things nobody would dispute.
Agreed. It does not follow from “all primates have genes” that therefore all primates evolved by itself unguided.
Well it seems to me you’re the one who WANTS to discuss it and I simply don’t care about linguistics. I want to focus on actual biology.
In succinctly quotable form please. This is internet.
Darwin did. Since we are already a page away from his quote, let me repeat it.
“It may be worth while to illustrate this view of classification, by taking the case of languages. If we possessed a perfect pedigree of mankind, a genealogical arrangement of the races of man would afford the best classification of the various languages now spoken throughout the world; and if all extinct, and all intermediate and slowly changing dialects, were to be included, such an arrangement would be the only possible one. Yet it might be that some ancient languages had altered very little and had given rise to few new languages, whilst others had altered much owing to the spreading, isolation, and state of civilisation of the several co-descended races, and had thus given rise to many new dialects and languages. The various degrees of difference between the languages of the same stock, would have to be expressed by groups subordinate to groups; but the proper or even the only possible arrangement would still be genealogical; and this would be strictly natural, as it would connect together all languages, extinct and recent by the closest affinities, and would give the filiation and origin of each tongue.”
– Origin of Species p. 459 https://archive.org/details/originofspecies00darwuoft
Not only is Darwin insisting on common descent here, but also (a) he is doing it without any empirical evidence, except the leap of induction, (b) he is doing it appealing to (false or reductive – take your pick) analogy on languages, (c) every successive generation of biologists has swallowed this point unquestioningly, and (d) this illogic has historically spilled over to many other sciences, quite brutally affecting even philosophers who should know better.
False — speciation has been observed (see here and here).
Here it is you who insists on turning evolutionary theory into bad metaphysics. Try and stick with the science, please.
There’s nothing here that involves “basic logic” — just more questionable metaphysics and dubious grammar.
I’m not appealing to the dictionary definition of “unguided.” I’m appealing to how the word is actually used by biologists like Ernst Mayr and philosophers of biology like Elliot Sober.
Yes, the kind of meaning that words take on when used in scientific theories.
The majority of atheists might not see evolutionary theory and theism as compatible, but they are wrong. In any event, I can think of two prominent philosophers of biology, both atheists, who do think that theism and evolutionary biology are nevertheless compatible: Michael Ruse and Elliot Sober.
This idea that evolution is a refutation of Genesis 1 would certainly come as a surprise to theistic evolutionists, to the majority of Thomists, and also the majority of Catholics. Aquinas’s “creatio non est mutatio, and his distinction between primary causes and secondary causes, is pretty much all you need in order to make evolutionary theory and theism fully compatible.
If that’s true, it’s only because theism in the West is no longer classical theism but rather imagines God to be a sort of demiurge.
Certainly evolutionary theory eliminates the need for a providential demiurge to explain adaptation and speciation. Abiogenesis — if we were ever to settle on a sufficiently good explanation — would eliminate the need for a providential demiurge to explain the origins of life.
Frankly I’m astonished that you of all people would endorse the idea that evolutionary theory and theism are incompatible. Perhaps they are incompatible if one has a demiurgic conception of God, but from the perspective of classical theism. that conception is itself a form of idolatry.
Why can’t evolutionary theory be compatible with both theism and atheism?
Likewise. And philosophy of science.
Sterile species is not a species, but a contradiction in terms. About as good as saying that homosexuality is a gender.
Inter-fertile species are not distinct species. I can say so because I have read how Darwin defines species.
You keep making evolutionary theory out for something else than what it is in the view of those who matter, such as Darwin or Felsenstein.
This is a major misunderstanding on your part. Perhaps wilful. Here’s my point for the last time in yet another way.
Evolutionary theory, if we see it in terms of metaphysics of (spiritual) emanation, is perfectly compatible with theism. Obviously so, because the theory of emanation directly derives from theism. But Darwin’s theory, the one actually employed by scientists, is understood in reductive materialist terms.
No problem if evolution is not taken reductively. But it is. (“Reductive” means here: Species evolved in terms of a diverging tree-like genealogy and there are no causes outside of that tree.) It was reductive with some hesitation in Darwin’s work, because he still made references to God-of-the-gaps. But this pretention was dropped already in Darwin’s lifetime, because God-of-the-gaps was seen rapidly shrinking. God-of-the-gaps may be good enough for ID-ists, but it’s not good for theists.
Darwin’s evolutionary theory, as it stands since 1900’s, is not compatible with theism. According to your persuasion, the theory has no metaphysics (materialism or what not). On my view, metaphysics must be there for physics and the rest to be sensible. If metaphysics is said to be not there, then the rest does not make any sense and can be handwaved away in a rational debate. Your lowest point in this thread was when you asserted that there cannot be complete explanations, while there still somehow can be “genuine” ones.