Common Design vs. Common Descent

I promised John Harshman for several months that I would start a discussion about common design vs. common descent, and I’d like to keep my word to him as best as possible.

Strictly the speaking common design and common descent aren’t mutually exclusive, but if one invokes the possibility of recent special creation of all life, the two being mutually exclusive would be inevitable.

If one believes in a young fossil record (YFR) and thus likely believes life is young and therefore recently created, then one is a Young Life Creationist (YLC). YEC (young earth creationists) are automatically YLCs but there are a few YLCs who believe the Earth is old. So evidence in favor of YFR is evidence in favor of common design over common descent.

One can assume for the sake of argument the mainstream geological timelines of billions of years on planet Earth. If that is the case, special creation would have to happen likely in a progressive manner. I believe Stephen Meyer and many of the original ID proponents like Walter Bradley were progressive creationists.

Since I think there is promising evidence for YFR, I don’t think too much about common design vs. common descent. If the Earth is old, but the fossil record is young, as far as I’m concerned the nested hierarchical patterns of similarity are due to common design.

That said, for the sake of this discussion I will assume the fossil record is old. But even under that assumption, I don’t see how phylogenetics solves the problem of orphan features found distributed in the nested hierarchical patterns of similarity. I should point out, there is an important distinction between taxonomic nested hierarchies and phylogenetic nested hierarchies. The nested hierarchies I refer to are taxonomic, not phylogenetic. Phylogeneticsits insist the phylogenetic trees are good explanations for the taxonomic “trees”, but it doesn’t look that way to me at all. I find it revolting to think giraffes, apes, birds and turtles are under the Sarcopterygii clade (which looks more like a coelacanth).

Phylogeny is a nice superficial explanation for the pattern of taxonomic nested hierarchy in sets of proteins, DNA, whatever so long as a feature is actually shared among the creatures. That all breaks down however when we have orphan features that are not shared by sets of creatures.

The orphan features most evident to me are those associated with Eukaryotes. Phylogeny doesn’t do a good job of accounting for those. In fact, to assume common ancestry in that case, “poof” or some unknown mechanism is indicated. If the mechanism is unknown, then why claim universal common ancestry is a fact? Wouldn’t “we don’t know for sure, but we believe” be a more accurate statement of the state of affairs rather than saying “universal common ancestry is fact.”

So whenever orphan features sort of poof into existence, that suggests to me the patterns of nested hierarchy are explained better by common design. In fact there are lots of orphan features that define major groups of creatures. Off the top of my head, eukaryotes are divided into unicellular and multicellular creatures. There are vetebrates and a variety of invertebrates. Mammals have the orphan feature of mammary glands. The list could go on and on for orphan features and the groups they define. Now I use the phrase “orphan features” because I’m not comfortable using formal terms like autapomorphy or whatever. I actually don’t know what would be a good phrase.

So whenever I see an orphan feature that isn’t readily evolvable (like say a nervous system), I presume God did it, and therefore the similarities among creatures that have different orphan features is a the result of miraculous common design not ordinary common descent.

3,738 thoughts on “Common Design vs. Common Descent

  1. When ornithologist Kim Bostwick goes hunting with her binoculars, she’s not just looking for birds; she’s looking for untold evolutionary stories.

    As if we need yet more evidence that evolution is story-telling.

  2. John Harshman,

    Now, if convergence were the result of design, wouldn’t we expect the convergent features to be identical rather than just fairly similar? Wouldn’t we expect octopus eyes and vertebrate eyes to be anatomically and developmentally the same rather than radically different in detail?

    It would depend on the design criteria. Since we observe diversity in life I would expect the design optimized to the animal and so therefor different.

  3. colewd:
    John Harshman,

    It would depend on the design criteria.Since we observe diversity in life I would expect the design optimized to the animal and so therefor different.

    Then why aren’t they optimized to the animal and its surroundings, rather than apparently determined by ancestry?

    You just make claims, you don’t demonstrate anything. We’ve got the apparent limitations of ancestry throughout life, you just have excuses that you never ever demonstrate to be true.

    Why don’t you actually try to do science with ID instead of excusing its lameness and looking for evolution killers? Because even if you showed that evolution doesn’t work–nothing you’ve come close to doing–you’d still have to begin showing that design explains anything at all.

    Glen Davidson

  4. Mung,

    Nested hierarchies

    Common ancestry is conspicuous.
    Evolution predicts that living things will be related to one another in what scientists refer to as nested hierarchies — rather like nested boxes. Groups of related organisms share suites of similar characteristics and the number of shared traits increases with relatedness. This is indeed what we observe in the living world and in the fossil record and these relationships can be illustrated as shown below.

    cladogram illustration showing nested hierarchies

    In this phylogeny, snakes and lizards share a large number of traits as they are more closely related to one another than to the other animals represented. The same can be said of crocodiles and birds, whales and camels, and humans and chimpanzees. However, at a more inclusive level, snakes, lizards, birds, crocodiles, whales, camels, chimpanzees and humans all share some common traits.

    Humans and chimpanzees are united by many shared inherited traits (such as 98.7% of their DNA). But at a more inclusive level of life’s hierarchy, we share a smaller set of inherited traits in common with all primates. More inclusive still, we share traits in common with other mammals, other vertebrates, other animals. At the most inclusive level, we sit alongside sponges, petunias, diatoms and bacteria in a very large “box” entitled: living organisms.

  5. GlenDavidson,

    Why don’t you actually try to do science with ID instead of excusing its lameness and looking for evolution killers? Because even if you showed that evolution doesn’t work–nothing you’ve come close to doing–you’d still have to begin showing that design explains anything at all.

    I don’t think you can do science with ID beyond the surface level of design detection.

    Then why aren’t they optimized to the animal and its surroundings, rather than apparently determined by ancestry?

    A eye popping up twice with a different configuration that fits two different animals looks like design to me. The design requirement is a DNA sequence for an eye that fits the animal. All these eyes seem to fit. Where did that sequence come from?

  6. colewd:
    John Harshman,

    It would depend on the design criteria.Since we observe diversity in life I would expect the design optimized to the animal and so therefor different.

    No, no, you can’t use the existence of diversity in life to explain diversity in life. That’s circular. And you’re wrong. “Design optimized to the animal” doesn’t explain the patterns we see. Fish have eyes similar to those of mammals, not squid. It’s not the optimization to the animal that account for the difference, it’s the phylogenetic history. Fish have vertebrate eyes, while squid have cephalopod eyes, and yet the life styles of a squid and a fish are much more similar than either’s to a chipmunk’s.

  7. John Harshman,

    No, no, you can’t use the existence of diversity in life to explain diversity in life. That’s circular.

    I am using the observation of the diversity of life in order to make an inference that I would expect different designs of the components. This argument is in no way circular.

    Eye’s appear well fitted to all animal types with a diversity of size and shape. If you want to take on the details of the tradeoffs of eye design knock yourself out but it is above my pay grade.

  8. colewd:
    GlenDavidson,

    I don’t think you can do science with ID beyond the surface level of design detection.

    Then it really is nothing, isn’t it? The trouble is that you’ve depleted the meaning of “design” enough to fit anything, thus you can’t do any science, especially it can’t be falsified by any conceivable criteria that could exist in life.

    A eye popping up twice with a different configuration that fits two different animals looks like design to me.

    Sure, but what doesn’t look like design to you? If two functional eyes are the same, it’s common design, if they’re different but actually work properly (there has to be convergence if lens eyes are going to evolve more than once), they look like design to you. You don’t look for anything that might deflate your cherished belief, you only rationalize anything and everything to fit with your a priori claims.

    The design requirement is a DNA sequence for an eye that fits the animal.All these eyes seem to fit.Where did that sequence come from?

    Well there isn’t “a sequence” that fits both. There are some very deep homologies, according to some, but no sequence governing structure that is shared by cephalopods and vertebrates.

    Maybe I was wrong, your ideas are falsifiable, and were just falsified. Nah, I know better than that, now it won’t depend on “a sequence” for eyes that is shared across long-separated lineages. You’re just committed to design no matter what, and sans any meaningful evidence, while the reams of evidence for evolution is to be discounted by flimsy attacks and lame excuses.

    Glen Davidson

  9. colewd,

    The real obstacle to your acceptance of common descent is emotional, not scientific. The same is true of Sal.

    Instead of contorting reality to conform to your religious beliefs, why not modify your religious beliefs to better conform to reality? Or be brave and give them up entirely?

  10. colewd: There is no way to link to the page.

    keiths found it.

    Yeah, that’s pretty silly. People can look at birds and crocodiles and just see how closely related they are. Same with camels and whales. These aren’t even proper clades.

  11. John Harshman: No, no, you can’t use the existence of diversity in life to explain diversity in life. That’s circular.

    Now they complain about tautologies. But animals are diverse because they are different. Everyone knows that.

  12. Nice quote mine, Mung.

    What John actually wrote:

    And you’re wrong. “Design optimized to the animal” doesn’t explain the patterns we see. Fish have eyes similar to those of mammals, not squid. It’s not the optimization to the animal that account for the difference, it’s the phylogenetic history.

    You’re a bottom feeder, Mung.

  13. GlenDavidson: The trouble is that you’ve depleted the meaning of “design” enough to fit anything, thus you can’t do any science, especially it can’t be falsified by any conceivable criteria that could exist in life.

    Name one feature of a living organism that cannot be “explained” by evolutiondidit.

  14. keiths,

    The real obstacle to your acceptance of common descent is emotional, not scientific. The same is true of Sal.

    Is there a real argument in your future. Mind reading is not your strong suit.

    I would speculate that belief in universal common descent is emotional and not scientific at this point.

    Common descent is just an argument with strengths and weaknesses. For you it seems important as an ideological pillar of atheism. But I am trying to read your mind, my bad.

  15. colewd,

    Common descent fits the evidence literally trillions of times better than common design. The real obstacle to your acceptance of common descent is emotional, not scientific.

  16. colewd:
    John Harshman,
    I am using the observation of the diversity of life in order to make an inference that I would expect different designs of the components.This argument is in no way circular.

    In retrospect, I see that it isn’t circular, just very badly stated. My apologies. However, it’s still wrong, and you haven’t dealt with my counterexample.

    Eye’s appear well fitted to all animal types with a diversity of size and shape.If you want to take on the details of the tradeoffs of eye design knock yourself out but it is above my pay grade.

    When you say “eye design” you’re assuming your conclusion. Yes, the eyes of different species show adaptations, but why can’t evolution account for them? Fish eyes differ from chipmunk eyes in many ways, most of them explicable by adaptation to different environments. But the problem for your claim isn’t that. It’s the differences between fish eyes and squid eyes. Why should that exist? I know, it’s above your pay grade, but you’re the one making the claim for design on that basis. If you can’t explain it, you can’t legitimately make the claim.

  17. There are two nested hieararchies in question, and they are not equal. It would be helpful if people would describe which one they are talking about!

    There is the Taxonomic Nested Hierarchy which creationists were the first to pioneer. That is empirically demonstrable.

    Then there is the supposed phylogenetic nested hieararchy (PNH), which tries to explain the Taxonomic Nested Hierachy (TNH), but not very well. Example. the PNH says we are in the clade of Sarcopterygii (a lungfish-like creature). The taxonomic absurdity of such a claim should be blatantly obvious.

    Taxonomic Nested Hierarchies are empirically demonstrable. We have Eukaryotes and Prokaryotes. Eukaryotes have the orphan feature of membrane bound organelles.

    Within the Eukaryotes are single cell and multicelled creatures. We have some that lay eggs, some that don’t. We have Vertebrates and then invertebrates. We have mammals. The mammals are split into placental and marsupial forms. In Mammals we have Rhodents and Primates. In primates we have monkeys and humans. The taxonomic nested hierarchy defined by morphological orphan features should be beyond dispute. To a weaker extent, that taxonomy can be seen in individual genes or proteins, but not quite as prominently and distinctly. An example of the weakness taxonomy in individual molecules is in the Cytochrome C. A chimp and human’s cytochrome C is identical. However, when accounting for all characters, the taxonomic nested hierarchy is brutally obvious.

    A few people, like that maddog Joe G, insist there is no nested hierarchy. There maybe overlapping nested hierarchies that don’t give one unique nested hierarchy, but that not the same as saying there is no nested hierarchy.

    The notion of taxonomic nested hierarchies was well entrenched by creationists like Linnaeus who often said: “God created, Linnaeus classified (Deus creavit, Linnaeus disposuit)”.

    Then Darwinists came along and made a total mess of things by conflating their hypothetical phylogenetic hierarchies with empirical taxonomic hierarchies.

  18. There are two nested hieararchies in question, and they are not equal.

    There are many nested hierarchies, Sal. Christ, it’s like pulling teeth to get you guys to read and understand Theobald:

    This phenomenal corroboration of universal common descent is referred to as the “twin nested hierarchy”. This term is something of a misnomer, however, since there are in reality multiple nested hierarchies, independently determined from many sources of data.

  19. stcordova: The taxonomic absurdity of such a claim should be blatantly obvious.

    A clade is defined by common features, it doesn’t say that all the members are identical.

    We are mammals, that doesn’t make us dairy cows.

    Sorry, It isn’t obviously absurd at all that the taxonomic rank sarcopterygii includes Homo Sapiens. Why is it obviously absurd?

  20. Sal, see if you can read and understand the following, from Theobald:

    So, how well do phylogenetic trees from morphological studies match the trees made from independent molecular studies? There are over 10^38 different possible ways to arrange the 30 major taxa represented in Figure 1 into a phylogenetic tree (see Table 1.3.1; Felsenstein 1982; Li 1997, p. 102). In spite of these odds, the relationships given in Figure 1, as determined from morphological characters, are completely congruent with the relationships determined independently from cytochrome c molecular studies (for consensus phylogenies from pre-molecular studies see Carter 1954, Figure 1, p. 13; Dodson 1960, Figures 43, p. 125, and Figure 50, p. 150; Osborn 1918, Figure 42, p. 161; Haeckel 1898, p. 55; Gregory 1951, Fig. opposite title page; for phylogenies from the early cytochrome c studies see McLaughlin and Dayhoff 1973; Dickerson and Timkovich 1975, pp. 438-439). Speaking quantitatively, independent morphological and molecular measurements such as these have determined the standard phylogenetic tree, as shown in Figure 1, to better than 38 decimal places.

    If common descent is false, as you claim, then why does the morphological tree match the independently derived cytochrome c tree to an accuracy of better than 38 decimal places?

    To reject common descent, as you do, is flat-earth stupid.

  21. stcordova: Then Darwinists came along and made a total mess of things by conflating their hypothetical phylogenetic hierarchies with empirical taxonomic hierarchies.

    The construction of molecular phylogenies is pretty much done by the same method. Group organisms according to number of similarities. The more similarities, the closer together you group them.

    What is remarkable is the degree of consilience between independently constructed phylogenies. Particularly for large multicellular eukaryotes they converge on the same overall tree structure. It is this fact (the consilience between trees done from different data sets) you’re supposed to explain with “common design”. As in actually explain why exists and looks the way it does, not just declare “That’s how God wanted it”.

    And remember, you would consider consilience between independent phylogenies to be a strong indicator of common descent at some arbitrarily picked lower level of taxonomic rank (perhaps like Muroidea which includes rats, mice and other quite similar rodents).
    Yet at some point when we move up through the taxonomic ranks, you put your foot down and say no more. Suddenly, for no reason at all that seems to make any sense, you declare that the method of inferring a common genealogical relationship by detecting highly congruent branching structures from independently constructed phylogenies, stops being valid.

    THAT, Sal, is absurd.

  22. Sal,

    The issue is settled. It isn’t just “well, most evolutionary biologists believe in common descent, but there’s some strong evidence against it.” There is no scientific controversy. The issue is settled because the biological community is simply not stupid enough to reject common descent. If a hypothesis fits the evidence trillions of times better than its competitors, why would anyone be idiotic enough to reject it? (That’s a rhetorical question; it neglects the Jebus Effect).

    To reject common descent puts you in a class with the flat-earthers, or with Neil, who thinks that geocentrism is a workable theory. It’s crackpot territory.

  23. colewd,

    I would speculate that belief in universal common descent is emotional and not scientific at this point.

    Common descent is just an argument with strengths and weaknesses.

    Write out the number 10^38, Bill. That’s a 1 followed by 38 zeroes. Given that common descent is scientifically confirmed to an accuracy of more than 1 in 10^38, using the tree in Theobald’s Figure 1, do you really think that we need emotional reasons to accept it? The 10^38 does the trick for me, and for any rational person.

  24. Rumraket: The construction of molecular phylogenies is pretty much done by the same method. Group organisms according to number of similarities. The more similarities, the closer together you group them.

    No, that isn’t how it works at all. It would work if there were a perfect, universal evolutionary clock. But of course there isn’t. Lineages evolve at different rates, and there’s random variation even in ideal rates. Instead, organisms are grouped by fit of data to a tree under various models. Parsimony is one such model: pick the tree that minimizes the number of inferred independent events (i.e. homoplasy, multiple hits, whatever you want to call it).

  25. stcordova:
    There are two nested hieararchies in question, and they are not equal.It would be helpful if people would describe which one they are talking about!

    These days, they’re the same, because taxonomy follows phylogeny. But I suppose you live in the past, say around 1900, when fish were fish and men were men.

    There is the Taxonomic Nested Hierarchy which creationists were the first to pioneer.That is empirically demonstrable.

    I’d like to see you try, and then show how your demonstration differs from phylogenetic analysis. No, really. When you make a claim, you need to back it up with more than “it’s obvious”.

    Then there is the supposed phylogenetic nested hieararchy (PNH), which tries to explain the Taxonomic Nested Hierachy (TNH), but not very well. Example. the PNH says we are in the clade of Sarcopterygii (a lungfish-like creature). The taxonomic absurdity of such a claim should be blatantly obvious.

    Again, it isn’t enough to say it’s obvious. Nor does Sarcopterygii mean “a lungfish-like creature”. It never did, even in 1900.

    Taxonomic Nested Hierarchies are empirically demonstrable.We have Eukaryotes and Prokaryotes. [blah, blah, examples] The taxonomic nested hierarchy defined by morphological orphan features should be beyond dispute.

    What do you mean by “orphan features”? Some of your “orphan features” are clearly derived from previous features and so can’t by any stretch be considered orphans. Some of your supposed groups are not defined by features at all, but by lacking those features. How does that fit our “empirically demonstrable” scenario?

    To a weaker extent, that taxonomy can be seen in individual genes or proteins, but not quite as prominently and distinctly. An example of the weakness taxonomy in individual molecules is in the Cytochrome C.A chimp and human’s cytochrome C is identical.However, when accounting for all characters, the taxonomic nested hierarchy is brutally obvious.

    Nope, your taxonomic hierarchy doesn’t appear at all in the molecular data. The phylogenetic hierarchy does. So why are chimp and human cytochrome-c identical? Why do they both differ by one residue from a macaque’s cytochrome-c? Can you explain that? I can.

    Then Darwinists came along and made a total mess of things by conflating their hypothetical phylogenetic hierarchies with empirical taxonomic hierarchies.

    You have just attached adjectives to two terms without justifying them. You have explained nothing. Two hierarchies you claim to exist are not different in the way you claim. They’re different in two other ways, though: the classifications of 1900 and (what you’re calling the taxonomic hierarchy) were based on less data than those of today, and back in 1900 nobody was concerned about the difference between clades and grades. (I pick 1900 because it’s a round number; in fact, classifications have been changing and often improving continually since Linnaeus, though much more rapidly in recent years.)

  26. John Harshman,

    When you say “eye design” you’re assuming your conclusion. Yes, the eyes of different species show adaptations, but why can’t evolution account for them? Fish eyes differ from chipmunk eyes in many ways, most of them explicable by adaptation to different environments.

    Adaption to environment or designed for its habitat or some of both.

    The big road block for me the origin of DNA sequences that build eyes that appear to fit all the animals well. Genetic variation from germ line to germ line finding the sequence to build all the cells required for an eye through serendipity seems like a real stretch. With convergent evolution an encore performance is required.

  27. colewd: Genetic variation from germ line to germ line finding the sequence to build all the cells required for an eye through serendipity seems like a real stretch.

    It is a real stretch. Maybe I should sell evolution in a bottle to people planning to visit Las Vegas.

  28. colewd:
    John Harshman,

    Adaption to environment or designed for its habitat or some of both.

    The big road block for me the origin of DNA sequences that build eyes that appear to fit all the animals well.Genetic variation from germ line to germ line finding the sequence to build all the cells required for an eye through serendipity seems like a real stretch.With convergent evolution an encore performance is required.

    In other words, because eyes can be made more than one way you’re pretending that it’s all the worse for evolution.

    Meanwhile, we have yet to see any sign of any design cause capable of producing the same effects, let alone one that can’t break out of the ancestral limitations that are visible in life. So you drearily attack the only theory that has evidence for it, preferring something that has to be made out of thin air.

    Glen Davidson

  29. colewd,

    There is only one event that caused the transition from your parents germ cells to you.

    There are a whole bunch of other events that preceded that. That my parents met each other, and not other people, I would call a ‘lucky accident’ in exactly the same way as you lot sneer at mutation. The sperm and egg that led to me were themselves one of billions and millions respectively.

    But somehow you don’t have a problem with the chance aspect here, which stretches back 1.5 billion years or so. Lucky accidents all. But not a problem, for some reason.

  30. Genetic variation from germ line to germ line finding the sequence to build all the cells required for an eye through serendipity seems like a real stretch. With convergent evolution an encore performance is required.

    Bill, there’s something called “selection” that you should acquaint yourself with. In the meantime, how about that 10^38 number you are conveniently ignoring?

  31. Allan Miller: That my parents met each other, and not other people, I would call a ‘lucky accident’ in exactly the same way as you lot sneer at mutation.

    I’d be willing to bet that your parents met other people too.

  32. colewd,

    Genetic variation from germ line to germ line finding the sequence to build all the cells required for an eye through serendipity seems like a real stretch. With convergent evolution an encore performance is required.

    But some bloke-like entity just going ‘ping’ – twice – you’re A-OK with?

  33. Allan Miller,

    There are a whole bunch of other events that preceded that. That my parents met each other, and not other people, I would call a ‘lucky accident’ in exactly the same way as you lot sneer at mutation. The sperm and egg that led to me were themselves one of billions and millions respectively.

    But somehow you don’t have a problem with the chance aspect here, which stretches back 1.5 billion years or so. Lucky accidents all. But not a problem, for some reason.

    With all this serendipity we can identify the mechanism that created you. Low and behold it is a deterministic mechanism. The question is not the probability of the event. The question is what is the cause and is the proposed cause likely based on the probability of that cause getting the proposed results. I am 100% confident in the cause that created the great Allan Miller. Lets drop it down to 99.999 to leave room for the second immaculate conception 🙂

  34. colewd,

    With all this serendipity we can identify the mechanism that created you. Low and behold it is a deterministic mechanism.

    Is it heck. There is considerable stochasticity in the formation of a gamete – that’s why they are all unique. Likewise the gamete that ends up in a zygote is one of billions. People meeting a given individual rather than one of a few billion others, making love today rather than yesterday … all these factors are ‘lucky accidents’.

    I think you might need to look up ‘determinism’.

  35. keiths,

    Bill, there’s something called “selection” that you should acquaint yourself with. In the meantime, how about that 10^38 number you are conveniently ignoring?

    So an eye re appears fully functional by “convergent evolution” with no identified intermediates. Where does selection help here?

    Waiting for you to back up your claim with some detail. Are you familiar with the counter arguments against Theobald cytochrome c claims?

  36. Allan Miller,

    Is it heck. There is considerable stochasticity in the formation of a gamete – that’s why they are all unique. Likewise the gamete that ends up in a zygote is one of billions. People meeting a given individual rather than one of a few billion others, making love today rather than yesterday … all these factors are ‘lucky accidents’.

    All good but again we have a bedroom tested mechanism 🙂

  37. John Harshman: Instead, organisms are grouped by fit of data to a tree under various models. Parsimony is one such model: pick the tree that minimizes the number of inferred independent events (i.e. homoplasy, multiple hits, whatever you want to call it).

    Doesn’t that pretty much amount to the same thing in the end? It sounds really strange to me if it would group considerably more divergent sequences together in preference to grouping together those that are more similar. What am I missing?

    I understand that variations in the clock will produce unequal variations in the number of mutations in homologous genes, and that this can make some genes more similar, and others less so, when more mutations accumulate in one locus compared to another(and so the trees you get from different genes are not exactly identical, but they are still more similar than you’d expect from chance alone). But I don’t understand how picking the most parsimonious tree for a single gene does not, in the end, also end up having put more similar sequences on branchers closer to each other.

  38. colewd,

    All good but again we have a bedroom tested mechanism

    Which is not deterministic, however arch you may wish to be.

    Indeed, we have a mechanism for mutation too, or rather several. Again, not deterministic. I see no fundamental difference in the ‘lucky accident’ department.

  39. It seems to me Bill is making the mistake of thinking random is synonymous with “doesn’t have a cause”.

    All the stochastic, aka random aspects of biological evolution, still have physical and chemical causes, in the same way the random segregation of alleles during meiosis have physical and chemical causes.

    When DNA polymerase copies a chromosome, and makes a copying mistake, that mistake has a chemical and physical cause. The same is true for the error correcting machinery that attempts to detect and correct such copying mistakes, it is itself subject to making errors, and those errors also have physical and chemical causes.

    They’re random yes, but they’re not uncaused. Allan Miller is right, there is no in principle difference between the term random when used about the segregation of chromosomes in meisosis, or the term random in the biochemical and physical causes of mutation, or the selection events that bias the changes in frequencies of alleles in populations.

    If Bill doesn’t think random in evolution means uncaused, perhaps Bill can clarify what he thinks the word random means in evolutionary biology.

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