Introducing Geremy (and Behe)

John I do not mean to ignore your questions, it’s just a matter of neglect not intent. There so may of you to respond to and only one of me. As I see it evolutionary theory is designed to be a general theory of biology, but it is not. I think that population genetics still is limited to explaining current and recent genetic conditions, and that the coalescent theory is limited to species that share genes. My goal isn’t to make a speculative theory of everything, but rather to show that biological systems are too interconnected and the genetic mechanism of evolution are to limited to paint an accurate picture of biological history. These are the reasons that evolutionary explanations are limited.

Chromosomal changes are not driven by random chance mutations, but the shortened telomeres of old age.
Since chromosome configuration and number vary from species to species, I decided to look into what the known causes of chromosome change are, and this is how I learned about the role of telomere shortening. Here is how one paper explains this connection:

In the well-established tumorigenesis model, telomeres in human somatic cells gradually become shortened with each cell division. After 50 to 60 cell cycles, cells with shortened telomeres provoke replicative senescence by chromosomal instability and p53 activation, which is induced by the DNA damage response according to telomere shortening [76,77,78]. However, some cells that can overcome senescence by the acquisition of genetic mutations in p53 or other checkpoint proteins continue to proliferate; thus, telomeres become critically short, and apoptosis is subsequently induced (crisis) [79,80]. At this point, a minor population of the cells that activate telomerase (or ALT pathway) acquires immortality and proceeds to carcinogenesis [79]…
Given that telomerase-mediated telomere elongation is important for the infinite proliferation of TERT-positive cancer cells, genetic or pharmacological inhibition of telomerase activity in cancer cells induces gradual shortening of telomeres and eventual cell senescence or apoptosis [109,110,111]. Theoretically, the anticancer effect of telomerase inhibition would emerge earlier in cancer cells with shorter telomeres. In fact, short telomere length could be a predictive biomarker of telomerase inhibitors [[112]

To explain the differences in in chromosomal arrangements evolutionary theorists often claim that these changes are due to random mutations, followed by evolutionary bottle necks. There are two problems with this claim. One easiest problem with this model to demonstrate are the claimed bottlenecks need to fixate the number of changes. After reading about the long chain of chance events, followed by a severe population bottleneck needed to claim that human chromosome 2 fusion happened just by chance. I wondered how many bottlenecks would it take to explain the chromosomal differences between humans and gibbons. Which is how I learned about the research of one oncologist who asked the same question. He writes:

How many bottlenecks are required to generate this kind of karyotypical mess between closely related species? a Gibbon (Hylobates lar) karyotype in comparison to b human karyotype based on correspond- ing color code. Every sporadic chromosomal aberration reduces fertility of heterozygotes due to loss of genetically unbalanced offspring.

https://www.researchgate.net/publication/260091237_The_telomeric_sync_model_of_speciation_Species-wide_telomere_erosion_triggers_cycles_of_transposon-mediated_genomic_rearrangements_which_underlie_the_saltatory_appearance_of_nonadaptive_characters

The above researcher then develops his own hypothesis of convergent evolution based on progressive telomere erosion while I am not endorsing his hypothesis, I think that the if one wants to claim that chromosome differences are all due to chance driven mutations there would need to be some explanation other than countless low probability mutations, which would cause countless population bottlenecks. The researcher above is aware of the second problem of telomere shortening due to his research in cancer, as I read the profiles of evolutionary biologists who think that there broader theory of evolution is not explained by the current theory I noticed that many of theses biologist are cancer researchers, and physiologists. The reason that I think that this is the case is because cancer researchers get to see the causes and effects of evolution up close in humans, and since different organisms have different genetic toolkits they can see that the sort of model organism based evolutionary explanations that are used to structure evolutionary theory, are not actually universal but confined to the species that have those abilities.

I think the true extent of common descent is unknowable from a scientific standpoint.

This is an interesting consequence of intelligent design, designers make choices even today, a human synthetic biologist might decide to print out functional gene sequences made from scratch, or she/ he may decide to modify existing organisms using guided evolution or both. Without knowing what the designer was thinking, one can not use science alone to demonstrate the limits of common decent, because intelligent agents can do things that chance alone can not. This fact is best explained by of all people Richard Dawkins with his Meme theory, a idea can be reproduced, and adapted to many situations just like a gene can be. So from the standpoint of intelligent design proteins, genomes, lipid structures are ideas, that we can best understand in the terms of mathematics and physics.

To illustrate this point let’s look at the theory of endosymbiosis, which explains that both chloroplasts and mitochondria are remarkably similar to bacteria, and so hypothesizes that their ancestors were bacteria. From an ID perspective bacteria, archaea and eukaryotes all began as ideas in a mind, so the hypothesis that an intelligent agent could combine elements of each to make something new is simple and easy to understand from an engineering standpoint. Now lets look at it from a blind chance perspective. A eukaryotic cell is much more than a just an archaeal cell with mitochondria, so even assuming that an ancient eukaryote engulfed bacteria long ago wouldn’t in itself explain the origins of eukaryotes. So the more common speculation is that an ancient archaea host cell engulfed a bacterial cell and developed a symbiotic relationship. Of course there is one huge problem neither archaean nor bacteria are capable of phagocytosis, so how did this happen in the past? Despite the claims of some researchers there are no demonstrably transitional organisms between archaean and eukaryotes, the claims about Lokiarchaea such claims are contradicted by available data, such as the paper that I linked below:

As I mentioned in an earlier post mutations are caused by physics, so some genetic sequences are simply more stable than others. As explained in Koonin’s common descent paper that I mentioned earlier it would absurd to credit all of this similarity to convergent evolution, however it is not absurd to think that an intelligent agent would use the most stable genetic sequences over and over again to prevent the destruction of these sequences by evolution. This is why I do not agree that phylogenetic trees are genealogical unless common ancestry can be demonstrated by other evidence.

Genome interconnectivity makes gene driven evolution impossible
As I mentioned in an earlier paper most complex traits are spread throughout the entire genome, this design feature is a good way of inhibiting the impact of gene evolution. Another way would be to place the global regulation of genes outside of the reach of physics driven gene evolution. I think that mechanobiologists who think that gene regulation is regulated by mechanical pressures have it right, and that the biologist here who don’t see how such a system of mechanical pressure regulation of the genome can inherited across the theoretical evolutionary tree of life, see the exact same problem that I see and if the above can be demonstrated to be true, the only real solution will be ID, because it is simply a brute fact that intelligent agents can do things that blind natural forces cannot.

So how could mechanobiology regulate gene transcription? This is a long conversation already so I will only provide one example taken from a mechanobiology paper, it explains:

Like twist, tension in the substrate DNA can be critical to this sort of long-range regulatory function. DNA loop formation is driven by thermal fluctuations and intracellular interactions that randomly bend and twist the DNA. When two binding sites come in close proximity to one another, a regulatory protein may form a bridge between the operators to generate a loop in the intervening DNA. The force associated with thermal fluctuations, needed to form such a loop, can be estimated from the persistence length of the DNA at around 0.1 pN—only a fraction of the scale of forces exerted on the DNA during normal cell functioning, like those discussed in §1. It was, therefore, predicted that forces as small as a few hundred femtonewtons could supersede the thermal fluctuations and easily suppress the rate of formation of protein-mediated DNA loops [43,44], effectively preventing all loop formation and, in turn, dramatically altering transcription levels…

In a separate experiment, Chen et al . [46] found that by applying a fluctuating level of tension to the DNA they could greatly enhance the rate of loop formation. The experiment was meant to simulate the fluctuating micromechanical environment of the cellular interior, where fluctuating forces arise from a wide range of intracellular processes. The introduced fluctuations were formally equivalent to increasing the effective temperature of the system and it was found that the loop formation rate could be more than doubled by adding an effective temperature of only 10 per cent of the thermal background. This rate enhancement, owing to force fluctuations, might explain why DNA loops result in a several 100-fold level of repression in vivo [47] despite the observation of equal lifetimes in the looped and unloooped states in vitro . Moreover, the sensitivity of the loop formation rate to the additive fluctuations was shown to be independent of the baseline static tension in the substrate DNA. This led the authors to suggest that schemes which employ mechanical tension as a regulatory switch can be surprisingly robust even in a mechanically noisy environment.

So this is why I consider evolutionary tree of life to be speculative.

Not exactly evidence against. However, there is at least one problem in this claim that seems to me to be insuperable, and which proponents of ID Creationism virtually never even acknowledge, let alone address.

Evolution is a theory that explains how Intelligent Designers come into existence without any need for such a being at the outset.

ID, OTOH, presumes the existence of such a being prior to the existence of living things.

The problem is that every single instance we have of an Intelligent Designer is of a living thing. So if living things require the prior existence of an Intelligent Designer, it would appear there is no possibility of living things coming into existence, since this would require that living things called Intelligent Designers have already come into existence. There is no way for this circular process to get started.

So I’d be interested to see if you have any solution to this problem that does not encounter the same sort of problems that you find so vexing when you try to understand evolutionary theory. Thanks in advance.

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It’s not at all controversial in the field of gene regulation to acknowledge that genes are regulated, in large part, due to looping interactions between regulatory sequences and promoters. This physical looping is demonstrably driven by the binding of transcription factors and co-activators, histone modifications, etc. It’s still not clear to me how any of this is supposed to hinder evolution.

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This paper has been convincingly responded to by the original authors (Spang et al) and independent groups, e.g.:
https://www.nature.com/articles/s41559-019-1040-x
and
https://www.nature.com/articles/s41586-019-1916-6

The data currently supports the fact that the Asgard archaea are sister to eukaryotes.

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I’m sorry, but your reasons were gibberish. I don’t know what “a general theory of biology” means. Population genetics can explain conditions in the distant past as well as th present. All species share genes. And I’m not sure what you mean by “biological history”.

You need to learn the difference between germ line and soma. Your paper is talking about somatic mutations.

No bottleneck is necessary. Nor is any long chain of events, just one event. Your source was wrong. And in fact it looks like a crackpot article.

You may think so, but you have no basis for that belief. Again, you resort to gibberish. But there’s a kernel of truth: one can never reject design, because an omnipotent designer could produce results that look like anything, including common descent. In other words design “explains” everything and therefore nothing. That makes the theory of design scientifically useless. All science can do is suppose that if it looks like common descent, it isn’t something else.

This is the central problem of the autodidact: you read to look for confirmation, misunderstand much of what you read, and put it all together in nonsencical ways. Nothing you say here suggests that mechanical forces can be inherited, as indeed they can’t. Nothing you say here deals with the vast amount of phylogenetic data, which you seem never to have looked at. And you have yet to articulate any clear point.

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I’m going to divide this answer into three parts, first let’s talk little about your first few points:

I’m sorry, but your reasons were gibberish. I don’t know what “a general theory of biology” means. Population genetics can explain conditions in the distant past as well as th present. All species share genes. And I’m not sure what you mean by “biological history”.

There are general theories and specific theories, I am saying that evolution is a specific theory. As far as population genetics there is a huge difference between explaining something and explaining something accurately. And biological history is the history of life on earth that you call evolution, which creationists call creation, I am calling biological history so as to not project explanations that can not be supported with scientific evidence, that doesn’t assume the existence of any particular processes, it is just a neutral statement.

You need to learn the difference between germ line and soma. Your paper is talking about somatic mutations.

This is a fair point, however telomere shortening in mothers has also been linked to chromosomal mutations in their children as explained in this paper, below:

No bottleneck is necessary. Nor is any long chain of events, just one event. Your source was wrong. And in fact it looks like a crackpot article.

The papers that I have read on the fusion of chromosome two all present a long chain of events beginning with the with the hypothetical ancestor of humans, chimpanzees and gorillas and ending with a chromosome fusion just in humans, as you can see in their Figure 5 shown here:

Now as far as the population bottleneck, this part of the explanation is made by papers that seek to explain why humans only have 46 chromosomes as opposed to some of us having 46 and others having 48, it seems to be non controversial that this would have required a bottle neck. Different authors have created various speculative scenarios such as this one:

From what I have read about chromosome mutations in humans there seems to be pretty good evidence that phonetically normal people with chromosome mutations have a higher incidence of infertility and birth defects as mentioned in the paper below, which states:

Nevertheless, carriers of balanced chromosomal translocations, while normal phenotypically, may experience reduced fertility, spontaneous abortions or birth defects.45 Normal meiotic segregation of these translocations in the gametes can lead to duplication or deletion of the chromosomal regions involved in the translocation.45 Reduced fertility in translocation carriers may in part be the result of the requirement during meiosis for chromosomal translocations to form a quadrivalent or trivalent structure (reciprocal and Robertsonian translocations, respectively) to enable homologous chromosomes to pair. The formation of the quadrivalent or trivalent can lead to reduced fertility, firstly, due to the mechanics and time constraints to form such a structure46 and secondly, as a result of the disjunction of the structures which is prone to produce genetically unbalanced gametes.

So if a single individual has reduced fertility due to a chromosome fusion an population dominated by individuals with this same mutation would only reinforce those fertility problems, at first until the genome stabilized, which from what I have read this could happen in two ways: Either there would be a reversal of the mutation by it being reabsorbed into the larger population without the mutation, or as happens with hybrid crops that are repeatedly bred together fertility rates would improve overtime within the small group, which would be a bottleneck.

Now all that I did was push the question back further the farthest that I could find any estimates was going back to gibbons, which is how I found a paper asking the same question. As you mentioned I am autodidactic here so there are obviously holes in my understanding so if you are aware of evidence that contradicts what I mentioned above, I will definitely read it. I will post answers to your other points as well but I think it best address theses points one at a time, my hope is that either we can agree on the need of population bottlenecks as a real world consequence of what evolutionary theory posits, or that you present evidence that demonstrates that chromosomal mutations could be universally fixated in a population without population bottlenecks, at which point I will happily admit that what I posted above is in error.

I think that data was a little too incomplete, to demonstrate the relationship that the authors intended to demonstrate. Here’s a paper written by a neutral third party, that includes much more data: https://www.biorxiv.org/content/10.1101/2020.10.19.343400v3

You have answered a request to clarify gibberish with more gibberish, I’m afraid. I can’t do anything with that.

This is not true. The history of life on earth is one of common descent. “Creation” is something else and is incompatible with that history. You may mean something different by “creation”, but so far you haven’t said what. If it doesn’t include common descent, however, it’s wrong.

That paper doesn’t show what you think. And that should be obvious, since every egg cell that a female will ever have is already present at birth. Older women don’t have different eggs, so germ line telomeres don’t get shorter as they age.

What I see is that there is a single fusion event. What’s the relevance of the other events to that?

It’s certainly speculative. I see no reason to propose a bottleneck.

Love that typo. Are you phonetically normal? There can be a higher incidence, but usually not a significant one for acrocentric fusions. That article is discussing all sorts of aneuploidy and various sorts of translocations and fusions. If there is no sizeable selective disadvantage to a fusion, it will evolve neutrally and will eventually be either lost or fixed. In the present case, the latter happened. That’s all. No bottleneck needed.

Where are you trying to go with this? You still haven’t presented any hypothesis of what actually happened. You’re just attacking the standard hypotheses. Makes it difficult to tell what you’re trying to say.

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I’m not sure why you cited Da Cuhna earlier then, if their data was too incomplete. You linked a non-peer-reviewed preprint, I will be interested to see how the final paper looks. It does indeed include more data which is certainly valuable. I look forward to seeing how researchers like Williams and Ettema comment on it. Assuming there are no problems with the analysis then this could at least muddy the waters, where currently it seemed there was a clear view of the 2D tree.

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Ok let me explain what I mean by specific theories of evolution. Very often I read about model organisms, for example in studying mammals mice are often used as a model species. However a mouse is not really a physiologically appropriate model for a human. Compared to humans mice are much more genetically diverse, with many different species and subspecies, and huge diversity within their species. For example there are hybrid zones where various species of mice freely mix despite chromosomal differences as mentioned in the paper below:

There is nothing similar to the hybrid zones of mice when you study humans, we only have one species, and have very little genetic diversity in comparison to mice. We also do not have groups of humans with different numbers of chromosomes, so we do not have the same genetic toolkit as a mouse, and so shouldn’t be expected to evolve in the same way as a mouse. At the same time no one would ever try to suggest that mice can use a human level of technical ingenuity to adapt to new environments, so why should we argue that humans have the same abilities to evolve genetically as mice which can breed with other species of mice? It would be much more complex but much more accurate to only use physiologically appropriate models

I also think that it is important to point out that hybridization between species with different chromosomes seems to be a routine method of creating stable Robertsonian translocations as mentioned in the paper below:

What I have yet to find is evidence that a chromosome fusion that wasn’t due to hybridization would not only not be a pathological mutation, but would take over a complete population without a population bottleneck that wasn’t based on assumptions, that it must have happened that way.

This is not true. The history of life on earth is one of common descent. “Creation” is something else and is incompatible with that history. You may mean something different by “creation”, but so far you haven’t said what. If it doesn’t include common descent, however, it’s wrong.

Common descent is a property of populations of living things so in a trivial sense it is true. The real question is the ability of one population of living things to give rise to another population with slightly different characteristics a sufficient causal mechanism to create all of the different population characteristics we see on earth? As I mentioned earlier if it isn’t, then whether life has an intelligent designer who chooses just to guide evolutionary processes, or a Creator who reuses the most stable genetic sequences by recreating them from scratch is dependent on the abilities and decisions of that designer. As far as I can tell physical constraints on reproduction would cause both progressive creation and common descent to be impossible to differentiate, to explain why in more detail I have to address my inability so far to explain my hypothesis about why ontogeny must be guided by mechanical constraints on gene expression.

Nothing you say here suggests that mechanical forces can be inherited, as indeed they can’t. Nothing you say here deals with the vast amount of phylogenetic data, which you seem never to have looked at. And you have yet to articulate any clear point.

This must seem true from your perspective so let me more clearly explain what it is that I am saying. Mechanical forces in biology are produced ultimately by chemical reactions, so by reproducing the same series of chemical reactions the same mechanical pressures are recreated. How mechanical forces are reproduced is easy to understand if we take the example of a vinyl record player. Mechanical forces created by sound waves which are nothing but pressure waves, reshape the surface of the record as it is rotated. This pattern of deformation is a three dimensional record of how to recreate the precise pattern of pressure waves in precisely the same sequence that originally created it. This is very much like what happens during ontogeny. I had to search for papers that refer to tensors and the mechanical pressures of ontogeny so as to explain this concept in a way that you are accustomed to, which led me to the following paper:

This paper explains:

At the surface of animal cells the cytoskeleton couples to integrins, which are transmembrane proteins that are part of macromolecular complexes called focal adhesions (Ingber, 2008; Wojtaszek, 2011). The intracellular domain of integrins binds to the cytoskeleton via actin-associated proteins such as talin, α-actinin, filamin and vinculin (Ingber, 2008). The extracellular domain of integrins binds to ECM proteins such as fibronectin, laminin, vitronectin and collagen (Baluska et al., 2003). In this manner, the inside of the cells is connected to the outside by a fibrous continuum linking the cytoskeleton, plasma membrane and ECM (Figure 1). However, focal adhesions are not fixed; they are dynamic and respond to mechanical stimuli exerted on the cells. When mechanical stresses are focused on these sites, focal adhesions change their shape and induce the influx of calcium through stress-sensitive ion channels, activate the phosphorylation of proteins and small GTPase pathways, and increase signaling through the cAMP (Mammoto et al., 2004). All these responses can stimulate the transcription of specific genes that in turn may affect the proliferative or differentiation fate of cells. For example, tension application to integrins activates Rho GTPases and its downstream effectors (Mammoto et al., 2004). This signaling cascade results in the regulation of the F-box protein Skp2 that controls the degradation of the critical cyclin-dependent kinase (CDK) inhibitor p27, which regulates the G1/S transition (Mammoto et al., 2004). Then, rather than just anchoring the cell to the ECM, focal adhesions function as mechanosensors that transmit the mechanical state of the ECM to the cell interior (Engler et al., 2006; Wojtaszek, 2011). The dynamics of cell proliferation, in turn, cause changes in the local tension and compression conditions and feedback to the mechanical state of the tissues (Weiss, 1959; Wojtaszek, 2011; Barrio et al., 2013). In this model, contractile actomyosin filaments, and other cytoskeletal components are the major tension elements that winch in the cytoskeleton against tent peg-like adhesions, and microtubules are considered to resist compression and to balance tensile forces (Ingber, 2008; Wojtaszek, 2011) (Figure 1).

So what I am saying is that the organization of the phenotype needs genes to code for proteins, enzymes, and other protein machines that generate cell movement, but that cell movement itself is governed mostly by the environmental cues and other non genetic effects that are beyond the reach of genetic evolution to construct. Instead I think that the mechanical pressures that emerge during ontogeny are actually what regulate gene transcription globally during development, as explained in this excellent paper below:

https://par.nsf.gov/servlets/purl/10064200

This idea seems to be understood by many developmental biologists, who are looking for some sort of external environmental input that is capable of enabling evolution, for example a paper that I mentioned earlier explained:

The second deadlock concerns the integration of ecology or, more precisely, the active role of the environment in phenotypic evolution. Over the last few decades, it has become increasingly clear that genes and genetic programs are simply not sufficient to explain the ontogeny of most morphological traits (see, for example, Goodwin 1982; Oster and Alberch 1982; Nijhout 1990; Alberch 1991; Webster and Goodwin 1996; Keller 2000; Pigliucci 2010). Instead, a more interactive view has emerged—treating genes and their organismic as well as external environment as influencing each other in a regulative feedback loop (e.g., Waddington 1957; West-Eberhard 1998, 2003; Odling-Smee et al. 2003; Kirschner and Gerhart 2005; Gerhart and Kirschner 2007; Gilbert and Epel 2009; Moczek 2012). In this view, the environment is not just passively endured by an organism, determining its chances of survival. It plays an active and essential role in development through phenotypic plasticity (West-Eberhard 2003; Gilbert and Epel 2009), and is itself altered by the activity of the organism (Odling-Smee et al. 2003). An obvious example of the latter is humanity’s ability to massively change and manipulate the environment to our own (short-term) liking and comfort. A number of useful concepts, such as facilitated evolution (Kirschner and Gerhart 2005; Gerhart and Kirschner 2007), genetic accommodation (West-Eberhard 1998, 2003, 2005a, b), and niche construction (Odling-Smee 1995; Laland et al. 1999; Odling-Smee et al. 2003) have been proposed to tackle this challenge, but a unifying and rigorous framework to deal with the active role of the environment in developmental evolution is still missing (Moczek 2012).

Now while evolution does not explain the origins of this type of information, work currently being done in materials science that involves the deliberate programming of structural information into chemical compounds may be an example both of how one could set up chemical reactions to create a series of mechanical forces that control chemical reactions, and how in fact cells show evidence of this very sort of process. Here’s a good almost 20 year old paper on that subject:

https://www.pnas.org/content/99/8/4769

Finally you mentioned phylogeny, as being something that I ignore, actually I have thought a lot about, and I think there’s a discrepancy between what it is and what it is thought to be. Phylogeny was originally designed by Ernst Haeckel to provide support for his “biogenetic law”, which claims that ontogeny recapitulates evolutionary history so phylogeny is an evolutionary interpretation of comparative ontogeny not a neutral test of the veracity of common descent.

If we think briefly about the hierarchical structure of our bodies. Our bodies contain many functional systems that contain organs, the organs are composed of tissues, and the tissues are composed of cells. This is an example of a nested hierarchy, similarly, the most complex proteins are made up of smaller proteins, which are made up of protein domains, so if one groups the proteins into families based on comparative function one should equally expect the tree like pattern to emerge, for the most part except for truly unique proteins for which the analogy of phylogeny being equivalent to common descent obviously doesn’t work. With this principle in mind let’s revisit the paper I mentioned earlier that talked about the testability of the hypothesis of universal common descent, the authors recreated an earlier experiment that tried to recreate an experiment that claimed to formally test universal common descent and came to the following conclusion:

This experiment demonstrates that the phenomenon observed by Theobald [4] is, indeed, entirely a product of “our ability to accurately predict the sequence of a… related protein relative to an unrelated protein” regardless of the actual history of the corresponding sequences. Alignments of statistically similar but phylogenetically unrelated sequences successfully mimic the purported effect of common origin. Thus, the nature and origin of the similarity between the aligned sequences are irrelevant for the prediction of “common ancestry” of proteins under Theobald’s approach. Accordingly, common ancestry (or homology, in the modern, post-Darwinian sense) of the compared proteins remains an inference from sequence similarity rather than an independent property demonstrated by the likelihood analysis.

Since it isn’t actually a neutral test but one based on the assumption of common descent, I see no reason to treat it as a neutral test.

Sadly, what follows explains nothing to me. I conclude that you are incapable of clear writing, possibly also that you’re incapable of clear thinking.

“Mouse” is a general term for a small rodent that isn’t a squirrel. But in fact the model organism often referred to as “mouse” is one particular species, Mus musculus. And that’s what’s in your paper: different populations of Mus musculus. Yes, humans have no chromosomal races. So what? The example shows that chromosomal differences don’t have to be a barrier to reproduction; it depends on just what those differences are. The many differences in size, technology, and such between H. sapiens and M. musculus are not relevant to this fact.

The second paper isn’t relevant to the situation in humans.

The situation in M. musculus is just such an example. All that’s necessary is that fertility not be significantly affected. Drift takes care of the rest. Most neutral mutations are quickly lost, of course. But a few become fixed, and the chromosome 2 fusion could easily have been one of them.

You are correct that sufficiently subtle guided evolution is indistinguishable from unguided evolution and that sufficiently subtle fiat creation is indistinguishable from common descent. But in either case, aren’t unguided evolution and common descent the simpler hypotheses and so should be accepted in the absence of incompatible evidence? And I have no idea why “physical constraints on reproduction” should be relevant here.

That’s not something you seem able to do. The record player analogy makes no sense whatsoever: what are the grooves in a cell? I ask again what you think are the differences between species that are inherited and allow similar-looking single-celled zygotes to develop into different sorts of organisms?

Then how are they inherited?

This is just not true. Haeckel is not the originator of phylogeny, and nobody models phylogenetic analyses after Haeckel’s claims.

It is, sort of. But not the sort that phylogenies cover.

One doesn’t group them based on comparative function. Have you ever read a single paper on phylogenetic analysis?

Theobald had a response to that. Have you read it? At any rate it’s not universal common descent you should be addressing, but common descent of species within families, or families within classes, and such. Here, try something simple:
https://www.researchgate.net/publication/10734528_True_and_False_Gharials_A_Nuclear_Gene_Phylogeny_of_Crocodylia

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Yet you didn’t; I say this as a mouse geneticist who has spent a lot of time looking at mouse-human synteny. Maybe keep things simpler?

False. If you disagree, please name 10 genes in mice that lack an ortholog in humans and vice versa.

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Sadly, what follows explains nothing to me. I conclude that you are incapable of clear writing, possibly also that you’re incapable of clear thinking.

Unnecessarily insulting and irrelevant to my clearly expressed point.

But in fact the model organism often referred to as “mouse” is one particular species, Mus musculus. And that’s what’s in your paper: different populations of Mus musculus. Yes, humans have no chromosomal races. So what? The example shows that chromosomal differences don’t have to be a barrier to reproduction; it depends on just what those differences are. The many differences in size, technology, and such between H. sapiensand M. musculus are not relevant to this fact.

The second paper isn’t relevant to the situation in humans.

First, you didn’t read the second paper at least not in it’s entirety, if you had you would have read this part:

The second (“post-zygotic”) scenario assumes the formation of post-zygotic reproductive isolation in the hybrid offspring through sorting of chromosomes (Rieseberg et al., 1995; Lukhtanov et al., 2015; Leducq et al., 2016) and gene alleles (Hermansen et al., 2014; Schumer et al., 2015; Blanckaert and Bank, 2018) resulting in genome or gene incompatibility between the incipient hybrid and both parental species. According to the chromosome-based version of the second scenario (=chromosomal model), two species differentiated by several fixed chromosomal rearrangements hybridize, and then, following an initial heterozygous stage, a new population system is formed that is homozygous for a novel combination of chromosomal rearrangements (Rieseberg, 1997; Coyne and Orr, 2004). Thus, under such a model, speciation is a consequence of the formation of a new recombinant karyotype (Lukhtanov et al., 2015).

The plausibility of the chromosomal model of HHS was shown in laboratory experiments on interspecific hybridization of some plants, where parents were artificially selected (reviewed by Coyne and Orr, 2004: 343-344). This model has also been studied in plants of the genus Helianthus (Rieseberg, 1997; Goulet et al., 2017). In animals, it was demonstrated in studies conducted on the butterfly subgenus Agrodiaetus (Lukhtanov et al., 2015). The latter study also demonstrated that the diploid chromosome number in hybrid species is drastically different from those in both parental forms if these are differentiated by multiple chromosome fusions/fissions. This model was also supported by findings in hybrid mammals (Giménez et al., 2016) and yeasts (Leducq et al., 2016).

So what hybrid mammals are the authors talking about? Mus muculus. So as I stated earlier the example of mice is not applicable to what happened to humans, unless one is saying that the chromosome fusion created partial sterility and a population bottleneck, as occurs with mice, butterflies and many other known examples of a chromosome fusion taking over a population.

In the above cases there are in fact different populations of animals with different chromosome numbers because that is a necessary precondition. This means that as some evolutionary biologists have understood for a long time, who disagree with you, that the unguided evolutionary narrative of the chromosome 2 fusion, requires the existence of an extreme bottleneck event, which led not only to the establishment of human chromosome 2 in all human populations, but at the very least the genetic extinction of all human populations in which this fusion did not take place.

I can imagine why evolutionary biologists who condemn the speculations of someone like a Richard Buggs who suggests that a extreme population bottleneck is recoverable and could demonstrate at least one way for there to have been a literal Adam and Eve, would hate to understand that the evidence supporting their unguided evolutionary narrative also requires a similar population bottleneck, however no one has ever showed me evidence that such claims are truly possible.

That’s not something you seem able to do. The record player analogy makes no sense whatsoever: what are the grooves in a cell?

Or perhaps you have such a low opinion of me, due to my hypothesis that theses physics driven processes constrain evolution that you ignored both the papers that I listed and my earlier posts on this subject? However to answer your question simply the cytoskeleton and the nucleus configuration, including the 3D configuration of the genome, are shaped by the mechanical pressures of gastrulation, and tissue migrigation in much the same way as a vinyl record is shaped by mechanical forces transmited by the needle. Please unless you have taken the time to read both the papers that I posted on my earlier answer don’t comment on this subject as if I am somehow an thinking illogically about it. From one of the papers that you haven’t yet had the time to read:

Mechanical and biochemical signals that are sensed at the cell membrane can result in the activation of tran- scription factors85–92, which are then recruited to their target sites to activate cell type-specific gene expres- sion programmes. For example, cells have been found to activate different genes when they are subjected to shear, compression or stretch3,4. In addition, plating cells on different surface topographies (polarized ver- sus isotropic) changed the shape of their nuclei, which resulted in the activation of different gene expression programmes78. Furthermore, cells plated on substrates with different topographies and rigidities can exhibit distinct behaviours in terms of proliferation, differenti- ation and apoptosis7,19,20. An earlier study showed that systematic tuning of the contact area between the cell and extracellular matrix resulted in altered expression of the extracellular matrix protein collagen93. These observations suggest three possible, non-exclusive mechanisms by which the microenvironment can regu- late gene expression: control of the nuclear import of different transcription factors, alteration of 3D nuclear organization and chromosome intermingling (BOX 1) and spatiotemporal mechanoregulation of gene clustering.

https://par.nsf.gov/servlets/purl/10064200

I ask again what you think are the differences between species that are inherited and allow similar-looking single-celled zygotes to develop into different sorts of organisms?

You seem to think that I am claiming that DNA is irrelevant to the situation here, when of course it is extremely important. It is true that some traits are simple Mendelian traits that can evolve as easily as evolutionary theorists think that they can, what I am saying is that most are not. The unique characteristics of a genome however is not limited to such simple traits, but also includes the great majority of complex traits that are spread throughout the genome and rely on the interactions of how the three dimensional architecture of that specific genome interacts with the histones, nucleus shape, cytoskeletal shape, to regulate those genes in a given tissue in a given species.

Then how are they inherited?

In the same way that we inherit the ability to form lipid bilayers, these constraints emerge from the chemistry and physics of cell to cell and cell to ECM interactions.

This is just not true. Haeckel is not the originator of phylogeny, and nobody models phylogenetic analyses after Haeckel’s claims.

Much like Haeckel believed that comparative morphology represented a true history of life on earth, modern phylogeneticists believe that by comparing DNA sequences that they are seeing the true history of life on earth, so the two ideas are mirror images of each other.

One doesn’t group them based on comparative function.

This is correct.

Have you ever read a single paper on phylogenetic analysis?

Yes, and I can now add one more now that I read your paper, and it seems to me that there is no way to know for certain what the root is, or from my standpoint if there is a root at all. All of the other molecular trees show separate ancestry, while the speculative root your team created can be used to create the appearance of common ancestry that matches the speculative cladistics based on morphology. While this is better than the complete mismatch that existed before it is based on your assumption that alligators are most analogous to the common ancestor of the other groups.

Since you asked me to analyze you work from a different standpoint I will now do that: I think that since the three dimensional architecture of the nucleus in stem cells regulates the expression of genes during develop, that there will automatically be a correlation between how similar a gene that is expressed in many different tissues during ontogeny gene is shaped, and how similar the morphology of of those organism will be. Now C myc is expressed in many tissues during development so there should be a general correlation between the animal’s morphology and the similarity in gene sequence. Also I think that some of the details that you used to rule out any sort of functional convergence such as snout length may actually be physiological traits as suggested by this paper here:

Thus, the apparent correlation between gene sequence similarity and morphology, is likely caused by the degree of cell shape morphology similarity, which seems to correspond to the degree of similarity in gene shape, resulting in multiple tissues, where C myc is expressed during development having shape similarity that corresponds to genetic similarity. Now whether those similarities are actually caused by common descent is dependent on the ability of evolutionary mechanisms to regulate the cell movements that shape the stem cells throughout the embryo in some still undiscovered way.

Let’s start by just focusing on the differences between human mouse and great ape telomeres using a couple of papers:

The telomeres of most laboratory mice are 5 to 10 times longer than in humans, but their lifespan is 30 times shorter…

Complete absence of telomerase has little expression in phenotype over several generations in mice, whereas heterozygosity for telomerase mutations in humans is sufficient to result in organ regeneration defect and cancer development…

Murine telomeres do not serve as a mitotic clock for replicative aging, as primary cells constitutively express telomerase, in contrast to humans, in whom telomeres play a part in replicative senescence and telomerase expression is repressed.5,29 In humans, the Hayflick limit is determined by telomere shortening, but murine fibroblasts stop dividing after 10 to 15 population doublings in vitro, before any appreciable sign of telomere erosion…

In mammals, telomere length inversely correlates with lifespan and telomerase expression inversely correlates with body mass,30 indicating that telomeres serve different purposes in different species and that telomere elongation and telomerase activation may represent an adaptive evolutionary advantage of small short-lived mammals in exchange for energy-expensive oxidative DNA damage mechanisms.30 Even within the rodent order, telomerase expression inversely correlates with body mass; while in large rodents (e.g., capybara, beaver) telomerase function is inhibited, small rodents (mouse) constitutively express telomerase in somatic cells, subverting replicative senescence.31

So we know of at least these four examples where we can’t use the telomere function in mice as models for telomere function in humans. In fact if we look at the four species most similar in gene sequence to humans we find difference in telomere function, as the study below explains:

Despite the high sequence conservation between genomes of higher primates at the nucleotide level, significant variations at the chromosomal structural level exist (33–35). One striking example is constituted by the heterochromatic caps found at the end of chimpanzee and gorilla chromosomes and absolutely absent from the orangutan and human chromosome ends. Recent in-depth analyses of sequence composition of duplicated domains linked to the heterochromatic caps indicated that these chromosome regions have evolved independently in the gorilla and chimpanzee lineages (19). Interestingly, although, the subterminal satellite Cht7 is associated with these heterochromatic caps both in gorilla and chimpanzee (21), supporting the notion that this association precedes the segmental expansion events that independently took place in both species. In addition, the Cht7 minisatellite sequences also co-localize with a heterochromatic region found in the middle of the long arm of chromosome 7 in chimpanzee (21), suggesting an association between minisatellite sequences and heterochromatic potential.

So I think it’s safe to say that while the sequences are very similar, that there are important functional differences between mouse and human telomeres, and that there are even significant differences in how telomeres function in humans and chimpanzees despite the high degree of genetic similarity overall.

It wasn’t intended to be insulting, just descriptive. Your point wasn’t clearly expressed — I still don’t know what it is — and you should know that.

What point are you trying to make? Still do’t know.

How so? Mus musculus is a single species, not of hybrid origin. That paper is talking about “chromosomal races”, some of which may be of hybrid origin, and some of which may be mutually reproductively isolated. What is your point, I ask again?

Further, the particular mice in question are not the relevant ones, which are the several populations in which there are chromosomal polymorphisms that don’t reduce interbreeding.

Precondition for what? Certainly not for fixation of an acrocentric fusion, which can occur in a single population.

What claims? What would that evidence be?

But you are. Nothing you have posted is relevant to anything I’ve asked about. Nobody is saying that mechanical signals don’t affect gene expression. But these mechanical signals are not inherited by gametes or zygotes. They can’t explain the differences among species.

What changes the three dimensional architecture of the genome so as to result in differences in adult morphology among species? Does that perhaps result from differences in genome sequences?

That doesn’t make a lot of sense. Lipid bilayers self-assemble; the ability doesn’t need to be inherited. Why do the chemistry and physics of these interactions differ among species? You still haven’t addressed that question.

Note that you have elided from recapitulation to comparative morphology. The latter actually does work pretty well, though genetics works better. Again, it’s unclear what point you’re trying to make by this facile analogy.

Then you haven’t read the paper. The rooting is by outgroup (birds).

They do not. Where did you get that idea?

I made no such assumption. Where did you get that idea?

What do you mean by “how a gene is shaped”? Do you understand that much of the sequence used in that study is not tra.?nslated and is excised from the mature mRNA? You should also know that phylogenetic analysis is not done by simple similarity.

That paper says nothing about snout length being a physiological trait, as indeed it isn’t; it’s a morphological trait. Nor did I use snout length to rule out functional convergence. Where, again, did you get that? The paper is simple, but you seem to have understood nothing in it.

That makes no sense. Are you familiar with the term “word salad”? And again, phylogenetic analysis isn’t about just similarity.

Word salad too. Whether sequence similarities are caused by common descent has nothing to do with cell movements but with the structure of the comparative data, a consistent nested hierarchy. We know what causes changes in DNA sequences: various sorts of mutations whose mechanisms are fairly well understood. You have to answer this simple question: why a nested hierarchy?

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Why? What point are you trying to make?

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He’s trying to impress you with how brilliant he is. How’s he doing so far?

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I am actually not, I have a perspective that is very different from yours. I do think that what I am saying is correct, however being correct has no relationship with brilliance. In my experience the people who are the most brilliant are just as likely to be wrong as anyone else, so it’s better to just try to gain a correct understanding of a subject by taking everyone seriously and keeping an open mind. I will find a way of explaining my ideas that will be easier to understand, in the meantime I hope that you are enjoying your weekend.

Why would we focus on telomeres when my question was about orthologs?

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Why on earth would you possibly believe that? Haven’t you been paying attention to all the people who have been patiently explaining to you why you are wrong (See @Mercer’s last comment for just the latest exampe)? Are you unable to understand their explanations? Is your ego too large to allow you to accept you are wrong? Or what?

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