Darwin Unhinged: The Bugs in Evolution

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(2017-10-23, 08:49 PM)nbtruthman Wrote: The "Weismann barrier" is the fundamental barrier to information transfer from phenotype back to into genotype, or in other words, significant hereditary information moves only from germline cells to somatic cells not the reverse. Significantly, creatively, violating this principle means the impossible requirements for both a reverse-engineering calculation from needed body/behavioral change to the corresponding required DNA changes plus an actual physical mechanism for the results of the calculation to be somehow transformed into the actual DNA changes in gametes.

I'm not sure what you're saying about the status of the Weismann barrier, but plants and some animals violate it:

https://en.wikipedia.org/wiki/Weismann_barrier

~~ Paul
If the existence of a thing is indistinguishable from its nonexistence, we say that thing does not exist. ---Yahzi
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(2017-10-23, 08:56 PM)Paul C. Anagnostopoulos Wrote: I'm not sure what you're saying about the status of the Weismann barrier, but plants and some animals violate it:

https://en.wikipedia.org/wiki/Weismann_barrier

~~ Paul

I pointed out how some plants can violate the Weismann barrier. Relatively simple animals like sponges and corals apparently are also exceptions to the rule and do it in roughly the same way, utilizing stem cell lineages that originate both body cells and gametes. But the mechanism is still random with respect to fitness variations culled by natural selection, with all the limitations of that mechanism. I think the Weismann barrier is still believed to apply to the vast majority of multicellular animals. 
(2017-10-23, 11:57 PM)nbtruthman Wrote: I pointed out how some plants can violate the Weismann barrier. Relatively simple animals like sponges and corals apparently are also exceptions to the rule and do it in roughly the same way, utilizing stem cell lineages that originate both body cells and gametes. But the mechanism is still random with respect to fitness variations culled by natural selection, with all the limitations of that mechanism. I think the Weismann barrier is still believed to apply to the vast majority of multicellular animals. 
The Wiki article suggests that it may not always be random with respect to fitness.

I won't be surprised if we find this happening in other animals.

~~ Paul
If the existence of a thing is indistinguishable from its nonexistence, we say that thing does not exist. ---Yahzi
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(2017-08-20, 02:41 AM)Kamarling Wrote: For example, I agree with Marshall that consciousness goes all the way down and is, indeed, universal. So the intelligence is in the system right down to the cell level thus there is no (or limited) need to invoke an outside agency. But I agree with Meyer when he says that however you imagine the intelligence, it is still Intelligent Design. In other words, I think he is suggesting that he is not pushing God the designer even though he personally believes that to be the case.
OK - I am back, now that Steve001 has kindly removed his remark about Alex and I from his posts!

I am just reading J Scott Turner's book, which also refers to consciousness (he prefers to call it cognition) going all the way down.

Basically I agree with that idea, but I don't think those who talk that way, quite realise how significant it is - or perhaps they do, but are trying to pick their way through the minefield of academic taboos in this area! When I have finished his book, I am going to try to contact him.

Conventionally consciousness is supposed to be an epiphenomenon of the brain, so accepting it plays a role 'all the way down' is a huge step.

David
(This post was last modified: 2017-10-24, 07:38 AM by DaveB.)
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(2017-10-23, 08:49 PM)nbtruthman Wrote: From a review of Transformations of Lamarckism, at https://dash.harvard.edu/bitstream/handl...sequence=1 :

I don't think any of the newly understood mechanisms of "soft inheritance" (including horizontal gene transfer) break the Weismann barrier or incorporate the kind of creativity observed in actual macroevolution. It seems to me that to be credible the "new Lamarckians" would need to show in detail how these "soft inheritance" mechanisms can creatively invent intricate complicated self referent irreducibly complex biological machines like the bacterial flagellum. There seems to be an irreducible requirement for the operation of mind, not mechanism. 

Perhaps we agree on this, but disagree on what the nature of that mind must be. 

Note that "random change, somatic mutation, somatic recombination or epigenetic change" are all random with respect to fitness.


Thanks again for a well thought-out response.  Ibid from the review you posted:
Quote: Weismann and his followers rejected the inheritance of acquired characters and promoted the allsufficiency of natural selection. Their strident language provoked a strong response from Darwinian pluralists and from others skeptical of the explanatory power of natural selection. Romanes (1888) wrote “The consequence of this kind of writing is that anyone who, like myself, still retains unmodified the Darwinism of Darwin himself, is ticketed as a follower of Lamarck … The school of Weismann may properly be called Neo-Darwinian: pure Darwinian it certainly is not.” And thus, neo-Darwinism entered the English language. Moreover, the polarizing message of the neo-Darwinists appears to have induced some scientists, who might not otherwise have done so, to identify themselves as latter-day Lamarckists. From a historical perspective, neo-Darwinism can be considered to have lost the argument because, in the ensuing decades, most biologists assigned a relatively modest or negligible role to natural selection in evolutionary change (Bowler 1983).
  (bolding is mine)

Haig, who authored the article is promoting his conservative view that bio-evolution is still in the neo-Darwinist camp and can evolve bringing forward most of the recent work.  In many ways this is true.  From my point of view, however, it cannot do so in context and the thheory must face a complete paradigm shift toward the mental influence of living things in their own construction.  Haig makes the same points that I did earlier, without putting Romanes and Darwin in the camp of "mental evolution".

I strongly disagree with the Weismannian bullbleep that "somatic mutation, somatic recombination or epigenetic change" are all random with respect to fitness. 

There is logical communication in natural language in biological systems.  Humanity included.  As we decode this language its functionality in solving problem and taking advantage of benefits offered by their ecological environments is blatantly obvious.  It is a "king with no clothes" situation for evolution that is random to information processing fitness.

Quote: "If there were something like a guidebook for living creatures, I think the first line would read like a biblical commandment: Make thy information larger. And next would come the guidelines for colonizing, in good imperialist fashion, the biggest chunk of negative entropy around."

Werner Loewenstein, a cell biologist at Woods Hole Biological Laboratories, has written a remarkably engaging book tying together information theory, thermodynamics, molecular biology, and the structure of cells. The subject is not one to which the human brain is well suited, but with Loewenstein's guidance you may get a better grasp on concepts like entropy than you've ever had before.
https://www.amazon.com/Touchstone-Life-Information-Communication-Foundations/dp/0195140575
(This post was last modified: 2017-10-24, 01:05 PM by stephenw.)
Biologist J. Scott Turner’s recent book Purpose and Desire seems to be representative of some of the latest thinking in alternatives to neo-Darwinism.

A few quotes that seem to give the flavor of Turner's thinking (from the review at https://evolutionnews.org/2017/10/scott-...own-words/):


"I will make a bald assertion: bacteria (or any living system, for that matter) can be agents because they are cognitive beings. Now, before going any further, I need to insert two disclaimers. The first is that I am using “cognition” in the broadest possible sense I can get away with — to mean simply the mapping of information about the external environment onto the cell’s internal workings. The second is that I am distinguishing cognition sharply from consciousness.
......................................
So, it seems to be cognition all the way down to the simplest life forms we know. Since cognition is an important component of agency, it follows that bacteria can be cognitive agents, as can any living system.
......................................
If Biology’s Second Law is true and life is at root an expression of the phenomenon of homeostasis, then the origin of life is tantamount to the origin of homeostasis. Homeostasis demands certain things, however — among them at least rudimentary forms of cognition and intentionality.... intentionality can be defined very broadly. (note: to apply even to simple biological structures like bacterial mats modifying their substrate according to what they "need")"

Comment: 
 
(For eukaryotic organisms especially ) Turner apparently relies on a Lamarckian idea of adaptive homeostasis becoming encoded somehow in another sort of memory system than a genetic one. He offers several alternate reservoirs to DNA for the processing and memory required: membranes, microtubule organizing centers (MTOC), and their cytoskeletons."


I still don't see how these speculations offer a plausible way to supply the evident deep ingenuity of biological nature in designing and implementing things like complicated irreducibly complex structures. To do this absolutely seems to require three basic stages: the analyzing of somatic requirements, then reverse engineering the results of that analysis into the DNA sequence changes and/or whatever extra-DNA encoded information changes that are required to make the needed bodily or behavioral changes (this can include a long complicated developmental pathway), and then physically making the required genetic and/or extra-genetic changes. This is a very high level of intelligent cognition combined with insight and intentionality. No one has proposed yet any actual natural mechanisms that can implement these functional requirements.

I'm not sure at this point that Turner's thinking is limited to it, but he seems to limit the "intelligence" of nature to the definition of simplified cognition previously quoted. I think more is required to have achieved what nature has achieved - it has required the operation of mind. Of course, to propose that would much more strongly violate the methodological materialist taboo against any form of teleology. But it seems clearly necessary to propose it, because of the evident "system requirements" of macroevolution outlined above.

The reviewer's summary: "Turner’s book is fascinating, stimulating, and befuddling by turns. He has interesting ideas but little to back them up, and in places the prose goes fuzzy, perhaps because there is little to go on. His ideas are only in the beginning stages, and need to be tested and evaluated, because they are controversial." 
(This post was last modified: 2017-10-24, 06:32 PM by nbtruthman.)
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(2017-10-24, 06:24 PM)nbtruthman Wrote: I still don't see how these speculations offer a plausible way to supply the evident deep ingenuity of biological nature in designing and implementing things like complicated irreducibly complex structures. To do this absolutely seems to require three basic stages: the analyzing of somatic requirements, then reverse engineering the results of that analysis into the DNA sequence changes and/or whatever extra-DNA encoded information changes that are required to make the needed bodily or behavioral changes (this can include a long complicated developmental pathway), and then physically making the required genetic and/or extra-genetic changes. This is a very high level of intelligent cognition combined with insight and intentionality. No one has proposed yet any actual natural mechanisms that can implement these functional requirements.
Why do you think that an "irreducibly complex structure" requires those steps?

~~ Paul
If the existence of a thing is indistinguishable from its nonexistence, we say that thing does not exist. ---Yahzi
(2017-10-23, 08:49 PM)nbtruthman Wrote: I don't think any of the newly understood mechanisms of "soft inheritance" (including horizontal gene transfer) break the Weismann barrier or incorporate the kind of creativity observed in actual macroevolution. It seems to me that to be credible the "new Lamarckians" would need to show in detail how these "soft inheritance" mechanisms can creatively invent intricate complicated self referent irreducibly complex biological machines like the bacterial flagellum. There seems to be an irreducible requirement for the operation of mind, not mechanism. 

I am uncertain about this. epi-genetics means that tags on DNA (methyl or acetyl groups) can be passed down to a child. These effects definitely seem to be real:
https://www.amazon.co.uk/dp/B00JFVOLZK/r...TF8&btkr=1
The problem is that ultimately these tags fall off, and no permanent genetic changes result - but maybe there is a way to make these changes permanent - even so they only affect the frequency of expression of the gene in question.
David
(2017-10-24, 06:24 PM)nbtruthman Wrote: Biologist J. Scott Turner’s recent book Purpose and Desire seems to be representative of some of the latest thinking in alternatives to neo-Darwinism.

A few quotes that seem to give the flavor of Turner's thinking (from the review at https://evolutionnews.org/2017/10/scott-...own-words/):


"I will make a bald assertion: bacteria (or any living system, for that matter) can be agents because they are cognitive beings. Now, before going any further, I need to insert two disclaimers. The first is that I am using “cognition” in the broadest possible sense I can get away with — to mean simply the mapping of information about the external environment onto the cell’s internal workings. The second is that I am distinguishing cognition sharply from consciousness.
......................................
So, it seems to be cognition all the way down to the simplest life forms we know. Since cognition is an important component of agency, it follows that bacteria can be cognitive agents, as can any living system.
......................................
If Biology’s Second Law is true and life is at root an expression of the phenomenon of homeostasis, then the origin of life is tantamount to the origin of homeostasis. Homeostasis demands certain things, however — among them at least rudimentary forms of cognition and intentionality.... intentionality can be defined very broadly. (note: to apply even to simple biological structures like bacterial mats modifying their substrate according to what they "need")"

Comment: 
 
(For eukaryotic organisms especially ) Turner apparently relies on a Lamarckian idea of adaptive homeostasis becoming encoded somehow in another sort of memory system than a genetic one. He offers several alternate reservoirs to DNA for the processing and memory required: membranes, microtubule organizing centers (MTOC), and their cytoskeletons."


I still don't see how these speculations offer a plausible way to supply the evident deep ingenuity of biological nature in designing and implementing things like complicated irreducibly complex structures. To do this absolutely seems to require three basic stages: the analyzing of somatic requirements, then reverse engineering the results of that analysis into the DNA sequence changes and/or whatever extra-DNA encoded information changes that are required to make the needed bodily or behavioral changes (this can include a long complicated developmental pathway), and then physically making the required genetic and/or extra-genetic changes. This is a very high level of intelligent cognition combined with insight and intentionality. No one has proposed yet any actual natural mechanisms that can implement these functional requirements.

I'm not sure at this point that Turner's thinking is limited to it, but he seems to limit the "intelligence" of nature to the definition of simplified cognition previously quoted. I think more is required to have achieved what nature has achieved - it has required the operation of mind. Of course, to propose that would much more strongly violate the methodological materialist taboo against any form of teleology. But it seems clearly necessary to propose it, because of the evident "system requirements" of macroevolution outlined above.

The reviewer's summary: "Turner’s book is fascinating, stimulating, and befuddling by turns. He has interesting ideas but little to back them up, and in places the prose goes fuzzy, perhaps because there is little to go on. His ideas are only in the beginning stages, and need to be tested and evaluated, because they are controversial." 
I have just finished this book, and am trying to discuss it with the author. My feeling is that he is picking his way through obvious academic taboos, and that his true position may be quite fluid. I suspect that he really is advocating teleology - otherwise, what is the point of the book?

I am sure he has a whole career of evidence to support his position, and that he hasn't written this book without lots of thought!

David
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(2017-10-24, 06:48 PM)Paul C. Anagnostopoulos Wrote: Why do you think that an "irreducibly complex structure" requires those steps?

~~ Paul
 
An irreducibly complex machine is a system which is composed of a number of interacting parts, where the removal of any one of the parts causes the system to cease functioning. These systems exist in organisms. The origins of such systems in biology are very hard for Darwinian mechanisms to account for, especially for the separate complicated developmental pathways. The unevolvability of such systems by Darwinian mechanisms is a probability argument - it might be remotely possible, but only through various tenuous and speculative stories of indirect evolution involving things like cooption, opportune alternate functions of intermediaries, etc., which would have to be specified for each small step of the neo-Darwinistic evolution of the system for the story to work. In other words, wildly speculative and unfalsifiable scenarios. In most cases no detailed sequences have been proposed. This problem for Darwinian mechanisms is one of the underlying motivations for most of the various proposed neo-Lamarckian and other schemes going beyond neo-Darwinism. 

Suppose for arguments sake that some irreducibly complex systems didn't evolve by long series of small steps via Darwinian mechanisms. Then it must have been some sort of act or acts of intelligence of some sort (not specifying the form of that intelligence). From basic engineering design and implementation theory (as applied to living organisms), it seems to me that this process must necessarily have either explicitly or implicitly involved the three steps described, regardless of the form of the intelligence involved.  

The process must necessarily start with analysis of the engineering requirements - defining what is the problem, perhaps doing a tradeoff study of different envisioned possible structural solutions to the problem. This stage, at least, seems to require engineering insight, especially with irreducibly complex machines. Then going on to the implementation part, which in biology is a reverse mapping of the envisioned new structure (functional change requirements) back into the corresponding genetic changes. Then, finally, implementing the change by going on to the actual physical modification of the genes or other extra-DNA elements. That's the way engineering works.
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