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Another rabbit jumps the hat: 419 mya JAWED fish

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Remember we were discussing how current Darwinian evolution theory would not be challenged even if a modern rabbit were found back in the 550 mya Cambrian era (and Darwin followers in the combox appeared to agree).

Hippety hop. A 419 mya jawed vertebrate.

The ancestors of modern jawed vertebrates are commonly portrayed as fishes with a shark-like appearance. But a stunning fossil discovery from China puts a new face on the original jawed vertebrate. [US$18 paywall]

National Geographic News reports*,

“Entelognathus primordialis is one of the earliest, and certainly the most primitive, fossil fish that has the same jawbones as modern bony fishes and land vertebrates including ourselves,” said study co-author Min Zhu of the Chinese Academy of Sciences in Beijing.

But in the new fossil, found in China, has a distinctive three-bone system still used by chewing vertebrates today: a lower jawbone called the dentary and two upper jaw bones called the premaxilla (holding the front teeth) and the maxilla (holding the canine and cheek teeth).

“The exciting thing about this fossil is that when you look at the top of it, it looks like a placoderm, but when you look at the side of the fish and the structure of the jaw, it doesn’t look like any placoderm that we know of,” Friedman said.

“This tends to suggest the exciting possibility that these jawbones evolved way deep down in the lineage, so these features we used to hold as being unique to bony fishes may not be so unique.”

In other words, less evolution and more stasis.

The fish seems to lave lived at the end of the Silurian period, 443 mya to 417 mya.

*Reports it, that is, under the curious title,

”Fish Fossil Has Oldest Known Face, May Influence Evolution“

Influence evolution? Baby, if they found it back then, it IS evolution. Unless, of course, you mean Evolution, the Religion. In other words, the fish may shake up your dogmatics a bit, but whose problem is that, besides yours, at this point?

Fish guy, yer gettin’ ta be a rabbit with me.

Comments
kf, She began her assault against Meyer by asserting he didn't know the difference between phyla and phylum. A statement so obviously wrong and so obviously contradicted by the very evidence she was attempting to use against him that the true objective was immediately apparent. Make it seem as if the book wasn't even worth picking up, much less given a serious reading. Of course, she was "preaching to the choir" over there at TSZ, and none of the "skeptics" I encountered (excluding Elizabeth) had read the book or even intended to read it anyways. And now I have serious reservations about whether Elizabeth really read it herself. But facts will speak for themselves. :)
There have been numerous quantitative studies of morphologic disaparity since the early 1990s, and many (but not all) have identified a pattern of great, even maximal disparity early in clade histories. Our qualitative reading of the diversification patterns for the Cambrian clades discussed in this chapter suggests that these explosion groups generally followed this same disparity pattern. ...We have tended to use a Linnaean framework precisely because great early disparity was the common mode shown during he explosion. - Erwin and Valentine. The Cambrian Explosion
Techniques developed to quantify the increased morphological diversity (what paleontologists term disparity) found during the Cambrian explosion have recently been applied to Ediacaran organisms. ... As in the Cambrian radiation (chap. 6), morphologic disparity increased more rapidly than taxic diversity. - Erwin and Valentine. The Cambrian Explosion
Mung
September 29, 2013
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Mung, its obvious EL is not constrained by facts, or by fairness. Meyer must be indicted as leader of a dangerous heresy as an enemy of humanity and found guilty. By any means necessary. That much is obvious. He's guilty, let's find some evidence to hook it on. KFkairosfocus
September 29, 2013
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"Elizabeth, so you agree with Meyer then, that disparity precedes diversity?" - Mung "No, of course I don’t." - Elizabeth But that's a question of fact, right? So you may be wrong.
The radiation of animal life in the early Paleozoic reflects a proliferation of body plans more than a multiplication of species. Two of the principle conclusions of James W. Valentine's research on the Paleozoic biosphere are that morphological diversification (i.e., increase in morphological disparity) is concentrated early in the history of animal phyla, and that clades show different patterns of morphological diversification depending on their level in the taxonomic hierarchy. ...some recent studies based explicitly on morphological data point to the same conclusions as the taxonomic studies...morphological diversification is most rapid early in the history of several major animal groups. ...There is also evidence that subclades within these major groups attained their maximal morphological disparity more gradually than the more inclusive clade. - Mike Foote. Evolutionary Paleobiology
Mung
September 29, 2013
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The text matches the figures Mung. The mistake is in both. He seems to think that Common Descent predicts something other than what we observe. It doesn't.Elizabeth B Liddle
September 29, 2013
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No, of course I don't. And yes, two sister groups precisely DO a phylum (or rather two phyla) make if they happened in the remote past and have branched many times since then, generating subgroup after subgroup But at the time of branching they will be morphologically close. You seem to be as confused as Meyer. Who is hugely overcomplicating things. It is very simple: Common descent says that organisms start similar, and branch out, becoming more diverse. Each big branch is given a "higher taxon" label, and sub branches "lower" taxon" labels. Everything on the branch is given that label, although some might be referred to as "stem" groups rather than "crown" groups. It makes no difference. What we see is what makes sense under Common Descent. Relabeling things makes no difference to the actual observations which form a tree.Elizabeth B Liddle
September 29, 2013
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Elizabeth, so you agree with Meyer then, that disparity precedes diversity?Mung
September 29, 2013
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Elizabeth, it's pretty funny to me how now it's about what Meyer wrote, not the drawings. Do you think it has escaped our attention that you quote Meyer twice in your OP, and as near as I can tell disagree with neither of those quotes? Perhaps if you had restricted your critique to the text... For example: Meyer:
The actual pattern in the fossil record, however, contradicts this expectation (compare Fig. 2.12 to Fig 2.11b). Instead of more species eventually leading to more genera, leading to more families, orders, classes and phyla, the fossil record shows representatives of separate phyla appearing first followed by lower-level diversification on those basic themes.
"Well, of course it does, Dr Meyer!" - Elizabeth Liddle. Of course, that's a matter of fact, not one of logic, wouldn't you agree?Mung
September 29, 2013
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Elizabeth Liddle:
Right. So we don’t actually call an ancient branching a branching into two “species”, but it is nonetheless a “speciation event”, whether it happened recently that all we have now is two species, or so long ago that what we have now are two phyla.
sigh. You are so confused. Two sister species do not two phylum make, whether now or in the past. Talk about errors in logic. To quote, once again, Briggs and Fortey (2005):
There are, by definition, no extinct phyla - only clades with living representatives merit phylum status.
And to quote from Figure 1:
Extinct taxa A to D belong to the stem group, but are not part of the phylum. The phylum is defined by five synapomorphies; extinct taxon D, which has just one fewer, is disqualified from membership.
p.s. And whether it was a speciation event back then or a speciation even now they are still two different sister species. Just because it happened "back then" doesn't make them not species.Mung
September 29, 2013
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Don’t you think you’re trying to make a mountain out of a molehill?
Only in the sense that Meyer's book is unlikely to be read by many people and certainly will have zero impact on the field of palaeontology, except possibly to distract the odd palaeontologist from her work in order to pen an exasperated review. But it certainly isn't a "molehill" in the view. Meyer bases a very large part of his book on his "hey disparity is supposed to follow diversity, and, look disparity comes first!" argument, which is nonsense. It only appears to make sense because Meyer thinks that phylum (or other "higher" taxon)=a group of organisms very different from another group, and that "phyla" also appeared before "genera". Without apparently noticing that when the phyla appeared they didn't consist of "a group of organisms very different from another group". And compounding his error by only circling round the late arrivals on the branch and calling only those organisms members of a phyla, not the ones at the root. And,to boot, circling paraphyletic groups.Elizabeth B Liddle
September 29, 2013
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Mung:
Do you think these diagrams that you find so egregiously wrong are intended by Meyer to be actual cladograms or phylogenetic trees, and if so, which are which?
No, I don't think they are supposed to be actual anything. It's a major fault of the book that he doesn't actually provide any actual computed cladograms. They seem largely to be general sketches of a principle (styled to look "back-of-the-envelope"), and some are supposed to indicate what "we would expect" under some theory that Meyer doesn't believe.
Do you think that in doing so Meyer intended to represent only monopyletic groupings?
I have very little idea what he intended to represent, but he certainly misrepresented the concept of a phylum, genus and family. Nothing in the text indicates that he is deliberately only circling branches that he thinks have extant or fossil representatives, and in any case that would be meaningless as they aren't specific anyway, just generic branchy things.
Do you know what an abstraction is?
Of course. But if these drawings are "abstractions" they are "abstractions" of a mistake.
How about a pedagogical illustration?
A pedagogical illustration should clearly represent what it is supposed to teach. If these illustrations are supposed to teach something, then they are teaching something wrong. Ironically, the drawings on which they seem to have been based are not nearly as bad.Elizabeth B Liddle
September 29, 2013
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Elizabeth, I have just a few questions for you: Do you think these diagrams that you find so egregiously wrong are intended by Meyer to be actual cladograms or phylogenetic trees, and if so, which are which? Do you think that in doing so Meyer intended to represent only monopyletic groupings? Do you know what an abstraction is? How about a pedagogical illustration? The Role of Abstraction in Scientific Illustration: Implications for Pedagogy Don't you think you're trying to make a mountain out of a molehill?Mung
September 29, 2013
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KF:
Nope, if an original species acquires such a load of new traits, it is no longer THE species, but a (much branched) descendant. If there is a howler here, it is yours, methinks.
Right. So we don't actually call an ancient branching a branching into two "species", but it is nonetheless a "speciation event", whether it happened recently that all we have now is two species, or so long ago that what we have now are two phyla. And the organisms that comprise that phyla are called members of that phyla whether they come from the root of the branch or the tip. And if two organisms, one from each of two phyla, coexisted near the root they would have been very similar. And if they coexisted near the tip, they would have been very different. Meyer can't have it both ways. But I appreciate you taking this seriously, KF. Someone on the ID side needs to take a good look at this.
Looking back at Meyer’s 2.11, p. 42, and laying aside the exact status of his circles for a moment, we can see the point. A circled cluster of particular related forms enfolds a set of species. As the hypothesised — NOT observed — process of macro evo proceeds, we move from one species to THAT SPECIES PLUS ITS DESCENDANT CLUSTER. In the second stage we have one cluster labelled Genus 1. By the third, new branches appear BELOW it, and within it. It is now higher on the tree. In the fourth, we can see ongoing branching and pruning back, presumably due to extinctions.
Well, drawing 2.11 is particularly awful, but I think it is supposed to represent the same true at different times. So branches can't appear "below" or it makes no sense at all. I think the branches on the left and right at the lowest level are supposed to be the same branches in every drawing. That's the only way I can make any sense of it at all. But what he seems to be trying to say in that drawing that when a branch initially gets going, it would be called a species, then, when it's been going a bit longer, and has some sub-branches, we'd call it something else. But that's nonsense because taxonomy is all retrospective. What we have is the fully grown tree, and from our vantage point we can see that what were two little species actually gave rise to two huge branching lineages with sub branches, and so we now call everything on one branch one "phylum" and everything on the other branch another.
Blend in a further factor, that taxonomical clusters should be based on observed clusters, and we can see one possible reason why he has drawn circles that cut in at a point above a single point ancestral node.
Well, no. This doesn't make any sense. In any case, it is completely unclear what the drawing is supposed to represent - if it is supposed to represent what we actually have fossils of, then it shouldn't be continuous. If it is supposed to represent what someone thinks actually occurred, then the portions labeled with a taxon should be a complete clade. They aren't. Sorry, KF, there is simply no excuse for these drawings. Meyer probably didn't draw them himself, but he must have commissioned them from drawings he wanted, and then looked at them carefully when he wrote the text. And indeed, he draws attention to the very features that are erroneous to make his point.
Meyer makes the strong emphasis on p. 41 that on Darwin’s explanation of his original tree diagram, diversity would precede disparity, i.e. morphological differentiation should expand across time from initially small differences to later larger differences reflected in higher classifications.
Yes, and it does. Low down in the tree there are fewer branches; higher in the tree there are more. But low in the tree the "morphological distance" between the "disparate" groups is as close as it is between "lower" taxa further up the tree. So the only "disparity" problem is created by the artefact of nomenclature - in living species, members of different phyla are more "morphologically distant" from each other than members of the same phylum are from each other. But we cannot extrapolate from living species to the point when the same two phyla had only just separated from each other. To a fictitious contemporary taxonomist they would just be two species, very similar, perhaps one with a two-ended nerve, one with a three, or five. Look a few hundred million years later and the descendents of the organism with a two-ended nerve have a spinal chord, and the descendents of the five-ended nerve column is starfish. Very "morphologically distant" at the ends - and, we would say "disparate", but not at the time where it matters. So diversity does precede disparity, just as Common Descent predicts, and just as the record shows. There is no "disparity first" pattern. There is simply a "higher taxonomic group first" pattern, which is entirely an artefact of the terminology.Elizabeth B Liddle
September 29, 2013
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EL:
For there to be “higher taxonomic categories”, then sure, species must accumulate new traits. But then it is the entire species that becomes the “higher taxonomic category” not just the organisms with “new traits” – these in fact will be part of what was a single “species” but is now labeled as a “phylum” or whatever.
Nope, if an original species acquires such a load of new traits, it is no longer THE species, but a (much branched) descendant. If there is a howler here, it is yours, methinks. Looking back at Meyer's 2.11, p. 42, and laying aside the exact status of his circles for a moment, we can see the point. A circled cluster of particular related forms enfolds a set of species. As the hypothesised -- NOT observed -- process of macro evo proceeds, we move from one species to THAT SPECIES PLUS ITS DESCENDANT CLUSTER. In the second stage we have one cluster labelled Genus 1. By the third, new branches appear BELOW it, and within it. It is now higher on the tree. In the fourth, we can see ongoing branching and pruning back, presumably due to extinctions. And, Genus 1 and 2 form a cluster by contrast with 3 and 4, so we now have two families, perhaps like dogs vs cats. Blend in a further factor, that taxonomical clusters should be based on observed clusters, and we can see one possible reason why he has drawn circles that cut in at a point above a single point ancestral node. If the ancestral node is hypothesised rather than observed, it is in fact outside the circle of observed species in a higher level group. So, I can see a possible reason why he could argue for circling the OBSERVED family but not all the way back to the root species, presumably not observed. And presumably with somewhat distinct characteristics that may not fit a pattern developed form observations. (Down that line lies the stem vs crown group issue, i.e. there would be a different cluster-able group emerged BELOW the "Genus 1," etc. Meyer did not circle, but that is not unreasonable. And indeed we can then see a pattern where a bigger yet circle might enfold the above and below. Providing you have observational evidence.) If the presumed root species is not observed, it is inferred not observed. And that would extend to higher levels of classification. Meyer makes the strong emphasis on p. 41 that on Darwin's explanation of his original tree diagram, diversity would precede disparity, i.e. morphological differentiation should expand across time from initially small differences to later larger differences reflected in higher classifications. Of course the whole point of 42 - 43 is to show that disparity precedes diversity. That was known to Darwin with specific reference tot he Cambrian but he expected new fossil finds to produce the pattern he predicted. As the fossil findings became more and more representative, the gaps would be filled. But instead, 150 years later [+ 250,000 fossil species, and millions of examples in museums with billions of similar specimens in the ground], we have seen the disparity first pattern reinforced. Hence the continued relevance of the Cambrian fossil revolution issue. KFkairosfocus
September 29, 2013
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If you picture the tree as a tree (root down), then a phylum will start lower on the tree than a genus. If you want to count number of twigs on a phylum, it will tend to be bigger than that of a genus. If you want to estimate the distance between one phylum and another, the answer will depend whether you measure near they it start or somewhere near where they finish.Elizabeth B Liddle
September 29, 2013
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Lower on the tree? Higher in the sense of a patriarch? Pardon my intrusion if I'm talking rot. It's certainly a subject I know nothing about.Axel
September 29, 2013
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For our solar system’s 10^57 atoms for 10^17 s changing state at the fastest rate for chem rxns (ionic) we see the entire set of possible observations standing as a one straw size blind sample to a cubical haystack 1,000 light years across [as thick as the galactic centre] relative to the number of configs accessible to 500 bits. For 1,000 bits, the capacity of the observable cosmos is even more dramatically swallowed up. That is the basis for thresholds of 500 – 1,000 bits.
I don't immediately see the importance of this for the particular topic, i.e. a clarification of what you meant by 'marginally plausible' in a particular context. I guess you've generalised the discussion to the same old talking point. Probably my mistake to think you were being more specific when you were talking about
Do the calc on numbers of new cell types needed from a single celled original form, thence new proteins, and compare the numbers on observed animals. You will see that the calc gets you to the low end on order of mag, and the observations are in the 100+ Mbit range. You will see an example in Meyer 2004.
And before that:
It can in fact be calculated that a new body plan, the relevant issue, will take about 10 – 100+ mn bits of new genetic info to account for unfolding the body plan from zygote or equivalent, and to provide cell types, tissues, organs and tightly integrated systems.
It's the math involved in the body plan quote I'm most interested in. I'd like to really nail that down: how many bit of new genetic 'info' does it take? Are you sure you don't have any academic references? Otherwise it's just all you think vs I think.Jerad
September 29, 2013
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KF, quoting Meyer:
For represenatives of higher taxonomic categories to arise, these new species must accumulate new traits and evolve further.
Nope. He's still wrong. For there to be "higher taxonomic categories", then sure, species must accumulate new traits. But then it is the entire species that becomes the "higher taxonomic category" not just the organisms with "new traits" - these in fact will be part of what was a single "species" but is now labeled as a "phylum" or whatever. I think what's gone wrong here is that Meyer is so hooked on the "ladder" view of evolution that he can't get it into his head that "higher" doesn't mean "more complex" or "more evolved" but simply category that includes sub-categories. So how are we supposed to believe anything else he says, when he gets this so completely wrong?Elizabeth B Liddle
September 29, 2013
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There does seem to be a problem with diagrams, though the fundamental point in the text is quite correct, as I have quoted. As well, in comparing 2.11, 7.3 and 2.12, I note that in 2.11 all three branches from a common point as circled, which looks a lot like he has captured the main point. You sound a lot like someoine looking for an error to dismiss, nto to engage the substantial matter.
I have fully engaged in the substantial matter, KF. The error is not confined to the diagrams, it is repeated over and over again in the text, including of course text in which he draws attention to the diagrams. He writes:
Darwin's theory implied that as new animal forms first began to emerge from a common ancestor, they would at first be quite similar to each other, and that large differences in the forms of life - what palaeontologists call disparity - would only emerge much later as the result of the accumulation of many incremental changes.
Which is correct. He then says this:
In its technical sense, disparity refers to the major differences in form that separate the higher-level taxonomic categories such as phyla, classes, and orders.
But this is only true when considering later members of taxonomic group - they all start similar at the root. But let's assume he means "later members of the taxonomic group" for now... He then says:
In contrast, the term diversity refers to minor differences among organisms classified as different genera or species.
Well, not always. Disparity can be part of the measure of diversity, but let that pass for now and use his definition...
Put another way, disparity refers to life's basic themes; diversity refers to the variations on those themes. The more body plans in a fossil assembly, the greater the disparity.
Yes. But now:
According to Darwin's theory, the differences in form, or "morphological distance," between evolving organisms should increase gradually over time as small-scale variations accumulate by natural selection to produce increasingly complex forms and structures (including, eventually, new body plans). In other words, one would expect small-scale differences or diversity among species to precede large-scale morphological disparity among phyla.
Yes, but only if we define phyla as later members of the taxonomic group. This is important. In both his diagram, and in his text, he is saying that phyla are separated from each other by a large morphological distance which is true if they are defined as later members of the taxonomic group. But not if they are defined as they are defined in biology. If they are defined as they are defined in biology they will be very similar near the node. He then says:
In [Darwin's] view, this process [of modification by natural selection] would continue until it produced differences in form that were great enough that taxonomists would classify them as new classes or phyla. In short, diversity would preceded disparity, and phyla-level differences would only emerge after species-, genus-, family-, order-, and class- level differences appeared.
No. Here is his problem. Using his idiosyncratic (i.e. wrong) definition of phyla, classes, etc, this makes no sense. If we do it his way, then (look at his diagram) we only recognise a phylum once it contains classes, and we only recognise classes once they are contained in a phylum. So using his nomenclature (wrong), they would happen at the same time. Or, any time he choose to circle, it seems. Using the correct nomenclature he has it precisely backwards. According to common descent, the roots of phyla will appear first, then classes, then orders, then families, then genera, etc. Sure, two phyla look pretty similar when you compare them near the root, but that's precisely what Common Descent predicts. By the time they have diverged, and are "morphologically distant" then of course a great deal of time has passed, and they contains classes, orders etc as well. But that doesn't mean the phyla came later. The basal nodes of the phyla of course preceded the subsequently nested classes, orders etc, just we would expect under Common Descent. So what we see in the fossil record (and which he draws crudely but more or less correctly) is exactly what fits with Common Descent. Meyer tries to say that Common Descent predicts the opposite, but that is because he has got his terminology confused, as is evident in both text and diagrams. Yes, it is incompetent. I think it's absolutely amazing that a man with no training in palaeontology thinks he can write an important book about palaeontology without even getting the basic terminology and concepts of the domain correct.Elizabeth B Liddle
September 29, 2013
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Jerad, For our solar system's 10^57 atoms for 10^17 s changing state at the fastest rate for chem rxns (ionic) we see the entire set of possible observations standing as a one straw size blind sample to a cubical haystack 1,000 light years across [as thick as the galactic centre] relative to the number of configs accessible to 500 bits. For 1,000 bits, the capacity of the observable cosmos is even more dramatically swallowed up. That is the basis for thresholds of 500 - 1,000 bits. KFkairosfocus
September 29, 2013
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F/N: I also suggest you have omitted the points made by Mung at 50 - 52 supra. Let me clip: ________ >> 50 MungSeptember 28, 2013 at 5:52 pm Elizabeth Liddle: Let me know either here or at TSZ what you disagree with. As you wish. :) I disagree with your entire approach of ignoring evidence inconsistent with your thesis and cherry-picking one half of one diagram and hanging your entire argument on it. “he circles only the tips of his drawings, not the whole branch.” Read on – diagram by diagram: Figure 2.8 on Page 36. Two groups are explicitly labelled phylum and those two obviously include all the sub groups. There are no circles to be found, at the tips or anywhere else. No “howler” here. But Elizabeth ignores this contrary evidence because it dosn’t fit her narrative. Figure 2.11 on Page 42. Family #1 is clearly drawn to include Genus #1 and Genus #2, and Family #2 is clearly drawn to include Genus #3 and Genus #4. just how far down the tree do you think he should have drawn the “family” circles and the “genus” circles? No “howler” here. But Elizabeth ignores this contrary evidence because it dosn’t fit her narrative. Figure 2.12 on Page 43. Once again Meyer usesthe term phylum. Two groups, which both clearly include classes and genera. There are no circles to be found, at the tips or anywhere else. No “howler” here. But Elizabeth ignores this contrary evidence because it dosn’t fit her narrative. So what does Elizabeth do? She cherry-picks a diagrem from Chaper 7. Figure 7.3 on Page 144. Even that diagram contradicts her narrative, but in true “skeptic” style she ignores that contrary evidence as well and forges ahead. On the right side of the diagram Meyer has, you guessed it, a phylum. It includes classes which include species. No “howler” here. But on the left hand side Elizabeth spies all the evidence she needs to convince her that the book can be ignored. 1. There are groups labelled phyla, not phylum. 2. While each “phyla” is drawn to include classes, the circles representing the “phyla” do not extend all the way to wherever on the drawing Elizabeth thinks they should extend. This is Meyer’s “howler.” And from this meagre bit of “evidence” Elizabeth claims to know that Meyer is ignorant of phylogenetics. That’s a bit of a stretch, imo. 51 MungSeptember 28, 2013 at 7:52 pm Mung: Do you mean to say that a phylum must include all no longer extant organisms which are believed to have given rise to the living members of the phylum? wd400: A taxon includes an ancestral species and all it’s descendants. Obviously, molecular phylogenies are (usually) limited to extant species (the tips), but that doesn’t change the definition of a taxon. You didn’t answer the question. Or you did, and you agree with me, but don’t want to appear like you agree with me. Please read my response to Elizabeth @50. In particular, see if you can help her draw where the circles in Meyer’s 7.3 ought to be. So as long a Meyer’s phyla each include an ancestral species and it’s descendants they qualify as a taxon. So where’s the howler? 52 MungSeptember 28, 2013 at 8:13 pm Further on Meyer’s alleged “howler.” Elizabeth, unfortunately for the case you are trying to make against Meyer, the facts are against you. > Defining the crown group as the phylum is convenient mechanistically, as it is straightforward to apply and avoids the difficulty of of how to separate members of sister phyla near their divergence from a common ancestor. It focuses on that part of the tree of life that includes extant animals and for which, therefore, molecular evidence is available. Restricting the concept of a phylum to the crown group as advocated by Budd and Jensen (2000) also has a number of drawbacks … > Figure 1A from their paper looks suspiciously like Meyer’s “howler.” Maybe they don’t understand phylogenetics either. > Debates about the Cambrian radiation have stimulated a debate over how “phyla” might be defined at all. One view bases a definition of phylum (or class) on the crown group and excludes stem groups as plesions. This has the advantage of objectivity and ensures that molecular data are available for the whole taxon except where primitive survivors pull fossil taxa into the crown clade.> Wonderful strife: systematics, stem groups, and the phylogenetic signal of the Cambrian radiation cf. A critical reappraisal of the fossil record of the bilaterian phyla. The Cambrian Fossil Record and the Origin of the Phyla >> ________ Seems there is more than one side to this story. But, while we are chasing away at a red herring led away to a strawman and soaked in ad hominems to be burned to poison and polarise the atmosphere, there is this, which is being missed, from Meyer, which is the main point, DD 142 - 3:
Darwin thought that the first representatives of the the higher taxonomic categories emerged after the emergence of the first representatives of each of the lower taxa . . . Instead, the first Cambrian animal forms are different enough from each other to justify classifying them as separate classes, subphyla, and phyla from their first appearance int eh fossil record (see Fig. 7.3. [i.e. p. 144]) This pattern creates an acute difficulty for the theory of punctuated equilibrium. [--> also] First, due to the action of allopatric speciation and species selection, advocates of punctuated equilibrium envision morphological change . . . arising in larger, more discontinuous increments of change, Nevertheless, like neo-Darwinists, they too see phyla-level differences arising from the “bottom up,” starting with lower level taxonomic differences — albeit occurring in increments involving whole new species rather than individuals or varieties within species. Indeed, according to the theory of punctuated equilibrium, allopatric speciation first produces new species in geographically isolated populations . . . For represenatives of higher taxonomic categories to arise, these new species must accumulate new traits and evolve further.
While you were busy straining at a gnat, you swallowed a camel. KFkairosfocus
September 29, 2013
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Do the calc on numbers of new cell types needed from a single celled original form, thence new proteins, and compare the numbers on observed animals. You will see that the calc gets you to the low end on order of mag, and the observations are in the 100+ Mbit range. You will see an example in Meyer 2004.
Okay. I may not have the time to follow up on this. It's something I'm sadly lacking in understanding. But it is interesting.
In any case the threshold for blind processes even being marginally plausible is 4 orders of magnitude below the low end.
Four orders? Are you sure? 10,000 times? Could you codify your criteria of 'marginally plausible' a bit? I'd rather be sure I'm actually addressing the issue you're raising rather than going off on an incorrect tangent. I understand back-of-the-napkin type estimations and I'm not going to object to that. I would like some indication of what limits you have put on your 'marginally plausible' zone.Jerad
September 29, 2013
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F/N: When you -- EL -- are willingly and in the teeth of correction, hosting a site that slanderously declares leaders and names the DI, as ENEMIES OF HUMANITY, you have forfeited the presumption of good faith. Your arguments are then to be seen from the position of a declared, ruthless and implacable enemy who has no respect or regard to people who s/he disagrees with, or for fairness or truthfulness. You may not like that but that is what you have earned. KFkairosfocus
September 29, 2013
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EL: There does seem to be a problem with diagrams, though the fundamental point in the text is quite correct, as I have quoted. As well, in comparing 2.11, 7.3 and 2.12, I note that in 2.11 all three branches from a common point as circled, which looks a lot like he has captured the main point. You sound a lot like someoine looking for an error to dismiss, nto to engage the substantial matter. KF Jerad, Do the calc on numbers of new cell types needed from a single celled original form, thence new proteins, and compare the numbers on observed animals. You will see that the calc gets you to the low end on order of mag, and the observations are in the 100+ Mbit range. You will see an example in Meyer 2004. In any case the threshold for blind processes even being marginally plausible is 4 orders of magnitude below the low end. KFkairosfocus
September 29, 2013
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KF: if it is to "taint" someone's competence to point out an enormous error, so be it. Yes, I think Meyer's book is incompetent. In fact I think it is obviously incompetent. I've yet to see a single person here defend his depiction of a "phylum" or a "family" as a paraphyletic group. Not surprisingly, because it is simply wrong.Elizabeth B Liddle
September 29, 2013
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I am contradicting Meyer on his understanding of what a phylum, or any other taxon is. As you seem to agree, it can either refer to a crown group or a crown+ stem group. Meyer circles, in his diagrams, something that is neither, and claims it is what various "Darwinian" models predict. It is not. Therefore his claim that what we observe is not what Darwinian models predict is wrong. Are you going to defend those diagrams or not? If not, let's agree that they are incorrect. Massively incorrect.Elizabeth B Liddle
September 29, 2013
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The opening of the OP at TSZ:
Quite apart from any factual errors, about which I’m not at all qualified to judge, here is what seems to me to be Meyer’s fundamental logical error IMO:
Mung
September 29, 2013
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So now you're contradicting Meyer on the facts, Elizabeth?Mung
September 29, 2013
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kf:
the above exchange where it seems you have tried to taint Meyer’s basic competence
Oh, there is no seems about it kf. None at all.Mung
September 29, 2013
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The problem with his diagrams, Mung, is that he is inviting us to contrast them. If one is correct, and the other is wrong, then the difference between them will be wrong, right? No, the case is not "awfully thin". Meyer has repeatedly, throughout the book, presented diagrams representing what is "expected" under "Darwinian" common descent, and contrasted it against "what we find". Often "what we find" is correct. What is wrong is "expected under Darwinian common descent". Eye-wateringly wrong. Your defense is of Meyer is rather like excusing someone from having a thumb on the scales by saying that they only had their thumb on one side.Elizabeth B Liddle
September 29, 2013
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Elizabeth Liddle:
Meyer’s diagrams neither circle crown groups nor crown+stem groups. His diagrams make no sense at all.
EL:
Failing to make an error in one diagram does not make the error in other diagrams go away
EL:
Figure 2.12 is correct.
Well pardon me if I thought you were lumping all his diagrams together as if they were all wrong and cherry-picking one to try to make a point. EL:
... the figures I am referring to are 2.11, 2.12, and 7.3.
Your case against Meyer is awfully thin, Elizabeth. Did you even bother to check the Bibliography? Did you even attempt to check the papers I referenced before firing off a response to me?Mung
September 29, 2013
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