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Topic: Phillip L. Engle: New Evolutionary Theory: The End of Ideology
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Pim van Meurs
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Member # 541
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posted 01. May 2004 00:23
Scott: I disagree with the proposal that Darwinian theory expects monophyletic groups or that monophyletic groups in any way provide evidence for the truth of Darwinian theory.
Why not? As I see it monophyletic trees is what would be expected from common descent, wouldn't it?
Scott: I do not believe that nested hierarchies as as strong as is commonly supposed. I do not believe that cladograms present us with nested hierarchies. I think that the topic of nested hierarchies would require its own thread, and so will not comment further here, as we are probably already getting a bit off topic for this thread.
Nested hierarchies are contrary to Scott's belief quite strong. Cladograms do not enforce nested hierarchies and would fail to provide nested hierarchies. It would be interesting to pursue this in a separate thread since I believe that nested hierarchies are 1) strong evidence for common descent 2) strongly supported by the evidence 3) compatible with Darwinian evolution. If nature failed to be nested hierarchically, cladograms would fail.
Douglas Theobalt presents the argument that
quote:
As seen from the phylogeny in Figure 1, the predicted pattern of organisms at any given point in time can be described as "groups within groups", otherwise known as a nested hierarchy. The only known processes that specifically generate unique, nested, hierarchical patterns are branching evolutionary processes.
Link
So while cladistics are succesful for nature they would fail to work for lets say cars
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Because of these facts, a cladistic analysis of cars will not produce a unique, consistent, well-supported tree that displays nested hierarchies.
[ 01. May 2004, 00:27: Message edited by: Pim van Meurs ]
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Scott
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posted 01. May 2004 01:53
quote:
So while cladistics are succesful for nature they would fail to work for lets say cars.
Patently false. Sorry Pim, no disrespect, but if you had done your homework you would know this is incorrect.
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Cladistics does not assume any particular theory of evolution, only the background knowledge of descent with modification. Thus, cladistic methods can be, and recently have been, usefully applied to non-biological systems, including determining language families in historical linguistics and the filiation of manuscripts in textual criticism.
http://en.wikipedia.org/wiki/Cladogram
There is no reason whatsoever that cladistics could not be applied to automobiles.
And to anticipate a further questions, do you really think that copying (descent with modification) does not occur in automobile design? And if so, what do you think distinguishes copying (descent with modification) in languages and texts from copying (descent with modification) in design? Inadvertent error?
In any event, how would this exclude the basic element of cladistics, synapomorphies.
regards
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Scott
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posted 01. May 2004 02:00
quote:
As I see it monophyletic trees is what would be expected from common descent, wouldn't it?
Does "common descent" predict monophyletic groups? I believe that the answer to this is no.
Would a polyphyletic group falsify "common descent"? I also believe that the answer to this is no.
Therefore, we cannot say that "monophyletic trees is what would be expected from common descent."
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nosivad
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Member # 767
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posted 01. May 2004 06:12
Both nosivad and Engle had disclosed their identities long before joining brainstorms. If Pim will not tell us who "we" are, then Pim should stop using that pronoun. It creates the illusion that brainstorms is a closed intellectual shop. I know of no example of an organism disappearing at the moment that it produced two new evolutionary products. Neither does anyone else. Evolution by splitting is biologically unsound. I am confident that new species were produced one at a time by saltational events for which I have provided a potential mechanism. The subsequent fate of the ancestor is of no significance to that process. There are numerous examples of related but distinct creatures coexisting for varying periods of time. Man and Neanderthal is an obvious example. Incidentally, if Neanderthal was not our immediate ancestor, just who was?
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nosivad
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posted 01. May 2004 06:36
I agree entirely with Scott's analysis of common descent. If evolution has been prescribed, as I now definitely believe, there was no barrier to polyphyletic origins in any lineage in which the required information was still present in as yet unexpressed or latent form. Please note my insistence on the past tense, as I see no prospect for new life forms being produced at present, at least by sexual processes. As I have repeatedly indicated, all tangible evidence indicates a highly conservative role for sexual reproduction. It prevents, rather than promotes, evolutionary change. To ignore that evidence, as the doctrinaire Darwinian continues to do, is inexcusable.
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nosivad
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posted 01. May 2004 07:27
I note that Pim has suggested that I and Engle may be one and the same. Considering our fundamental differences, that becomes the most remarkable statement ever to grace the threads of this or any other other forum. About the only thing we share is our mutual disillusionment with the Darwinian model. I can only conclude that is what identifies us as a single intellectual entity.
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Pim van Meurs
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posted 01. May 2004 13:45
Scott: Does "common descent" predict monophyletic groups? I believe that the answer to this is no.
Common descent based on inheritance and variation would indeed predict monophyletic groups.
Scott: Would a polyphyletic group falsify "common descent"? I also believe that the answer to this is no.
That depends, if cladistics or phylogenetic trees failed to provide a consistent picture when applied based on different data then such discrepancies would pose a problem for common descent. Would it falsify it? That would depend on the extent of the problem.
There are some obvious complications namely horizontal gene transfer which would lead to gene mixing and could lead to polyphyletic groups in earliest life.
Scott: Therefore, we cannot say that "monophyletic trees is what would be expected from common descent."
I think that does not logically follow. Common descent definitely predicts nested hierarchies and monophyletic trees in my opinion. The existence of horizontal gene transfer however can complicate the picture.
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Rex Kerr
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posted 01. May 2004 15:27
To the extent that descent is common, you get monophyletic trees. Of course, in any measurement you can have noise and uncertainty and thus the finer branches may not always be resolvable.
Lateral gene transfer is one mechanism that is outside of common descent. It appears to be exceedingly rare in multicellular eukaryotes.
You can always form a cladogram from any set of data. If the data was not produced by common descent, two things happen: first, the confidence of any given branch drops dramatically and contradictions pop up in pairwise similarity tables; and second, forming the cladogram from different subsets of the data produces different trees.
When expected levels of measurement noise are taken into account, cladograms from DNA sequences of multicellular eukaryotes show extremely good agreement with what would be expected from common descent.
(The cases where I have seen this not be the case were usually tracked down to a bad assumption when forming the cladogram, namely that rates of change are identical in every branch--which has little to do with common descent and much to do with a fond hope that reality will conveniently permit easy analysis.)
Note that common descent assumes independent modification in each branch. If descent is common, but there are coordinated (intelligent? predetermined?) changes in unrelated organisms, it would appear as though common descent were violated. This could perhaps be used to assess whether evolution has unfolded according to some grand plan, or whether guiding intelligence is responsible for evolutionary changes. I can't quite formulate a precise set of predictions based on that, but perhaps others in this thread can think about it.
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Phillip L. Engle
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posted 01. May 2004 23:57
A few brief comments:
When I described my article "Symmetry in Evolution" as providing "proof" that evolution proceeded symmetrically, I was obviously using "proof" in a colloquial, inductive sense. The article states a hypothesis and provides inductive evidence for it. Colloquially, this is commonly known as an inductive "proof". Obviously, the appearance of additional inductive evidence that is contrary to my hypothesis might cause me to revise my hypothesis: That's the way science works. To pull the word "proof" out of context and foolishly imply that what I thought I was presenting in the article was a DEDUCTIVE proof, and that therefore I "don't know how science works", is, as far as I'm concerned, a cheap shot that badly misfired.
The accusation that John Davison and myself might really be "the same person" is equally absurd. Both John and I have clearly indicated our respective backgrounds, and John has clearly indicated in this thread where exactly he disagrees with me. Far more likely is the hypothesis that the hard-core Darwinians on this thread are really "the same person", since they insist on remaining anonymous as far as THEIR backgrounds are concerned.
I agree that calling Darwinism a differing "paradigm", rather than an "ideology", is probably preferable for irenic reasons. My use of the term in the article that started this thread was intentionally provocative, since I see so little evidence for the Darwinian paradigm.
I think that Denton concedes too much on page 105 of his book EVOLUTION: A THEORY IN CRISIS when he says that "the axioms of typology have been shown to be inapplicable at the level of the species". The only reason that typology is APPARENTLY inapplicable at the level of contemporary species is the success of Ernst Mayer and other neo-Darwinians in defining the word "species" in such a way that it includes huge numbers of biological differences that were formerly thought to be differences between VARIETIES, rather than differences between SPECIES. Thus re-defined, "species" typology vanishes (or is severely attenuated) and is easily replaced by Darwinian random variation, natural selection, and population genetics.
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Rex Kerr
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posted 02. May 2004 06:16
Inductive proofs aren't proofs, except in mathematics. The colloquial usage of proof, meaning "argument for", tends to be avoided by researchers, since it is far too clumsy an instrument to relay the wide array of distinctions in degree of confidence that one has about one's results.
I'd recommend that one only use "proof" to denote things of great certainty, even in colloquial usage. Other lines of argumentation can be labeled as "evidence", "demonstrations", "indications", and so on.
The reason that the definition of species has been broadened is largely because finding a clear dividing point that could be determined with a reasonable amount of work has been rather difficult.
Since there is very nearly a smooth continuum of different degrees of separation from intra-species variation through to distinct genera, any robust method of describing these differences has to be able to cope with a wide variety of levels of difference.
Typology is easy to apply, but simply calling everything that can't be disinguished by typology is rather odd, since it can include reproductively isolated species (e.g. species of fruit fly of the genus Drosophila), and it can suggest distinctions between members of the same species (e.g. if we didn't know better (from breeding), we'd tend to think of Mastiffs and Chihuahuas as different species). The problem is that typology alone isn't enough, since it doesn't tell you when you have different species, and when you only have varieties. (Really careful typology could potentially pick out the same cladograms as DNA sequencing--and for more divergent species where this is easier, it typically agrees with genetics.)
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nosivad
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posted 04. May 2004 16:41
Populations became the necessary units of evolutionary change when it finally became transparent that individual organisms were not capable of evolving beyond the level of variety. It was and remains pure mysticism. Populations are what result when a species multiplies. Nothing more and nothing less.
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nosivad
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posted 04. May 2004 16:56
Incidentally, it was a staunch Darwinian, Theodosius Dobzhansky, who proposed a perfectly defined definition of species. If two forms either cannot interbreed or, if they should interbreed, whether naturally or artificially, produce sterile offspring, they will be considered to be separate species. There is nothing vague about this definition. The Darwinians keep complaining about how species are not well defined. If they cannot accept the definition offered by one of their own, no wonder Darwinism is in big trouble. I have accepted Dobzhansky's definition without reservation and used it in support of my position as presented in the paper "Is Evolution Finished".
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nosivad
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posted 04. May 2004 18:41
Rex Kerr
Your statement which begins with "Since there is a very nearly smooth continuum of different degrees of separation from intraspecific varieties through to distinct genenera etc etc." is unacceptable. It is precisely the lack of a continuum that makes the recognition of species and genera unmistakable. Your assertion is classic propagaganda, designed to promote darwinian gradualism. One starts with an assertion that is without foundation and then proceeds to draw all sorts of conclusions from it. It is a sad commentary on the failed Darwinian ideology.
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peter borger
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posted 05. May 2004 07:19
Davison is one of the guys who stands up against the Darwinian claptrap. I always agree with him. For several previously discussed reasons. Another comes from RNAi. Anybody familiar with RNAi knows that (neo)darwinian evolution is as dead as a dodo. RNAi shows that:
1) there is a flow of information from the soma to the germline
2) thus acquired traits are passed down to the offspring
Refs:
Tabara et al, Science 1998, 282: 430-1.
Grishok et al, Science 2000, 287: 2494-7.
Schramke et al, Science 2003, 301: 1069-74.
etcetra, etcetera
(Worms fed with or soaked in dsRNA not only integrate these signals in their genomes but can pass it on to offspring. Apparently it affects the germline. This is Lamarck speaking)
Why is Darwin still dominating the field of evolutionism? For the sake of outdated naturalistic philosophy, would be my guess.
Peebee
[ 05. May 2004, 07:22: Message edited by: peter borger ]
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RB
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posted 05. May 2004 09:08
(Worms fed with or soaked in dsRNA not only integrate these signals in their genomes but can pass it on to offspring. Apparently it affects the germline. This is Lamarck speaking)
PeeBee:
Nope. you are wrong. The dsRNA affects the mRNA levels of the chosen genes by directly destablizing the mRNA. The "signal" remains in the cytoplasm. The gene of interest is still actively transcribed, no genome changes. As for generational transmission, there is a half life. It is not a permanent change. The phenotype penetrance and expressivity drops in successive generations. Cytoplasmically inherited dsRNA is diluted over time and the phenotype stops. Your logic is like saying DDT or mercury exposure that shows generational transmission proves evolution false.
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