Comments 2

حدود جديدة للتطور

May 27, 2015 Tomoko Ohta

ميشيما ــ كانت الاختراقات التي تحققت مؤخراً في فهمنا للآليات الجزيئية سبباً في إحداث ثورة في العديد من مجالات البيولوجيا (علم الأحياء)، بما في ذلك بيولوجيا الخلية وبيولوجيا التطور. لذا فليس من المستغرب أن تزودنا هذه التطورات برؤى قيمة في مجال بيولوجيا التطور أيضا، بما في ذلك الأدلة التي تدعم النظرية شبه المحايدة للتطور الجزيئي والتي وضعتها عام 1973.

وكما هي الحال في عالَم العلوم عادة، فإن كل اكتشاف في مجال بيولوجيا التطور يثير من التساؤلات بقدر ما يجيب على تساؤلات أخرى. والواقع أن مجال عملي يمر الآن بواحدة من أكثر الفترات ديناميكية في تاريخه الذي امتد مائة وخمسين عاما.

على مدى قرن من الزمان تقريباً بعد نشر تشارلز دارون لكتابه "في أصل الأنواع"، كان العلماء يعتقدون أن الطفرات الجينية محكومة بعملية مشابهة لتلك التي وصفها مؤسِس نظرية الانتقاء الطبيعي. وكانت الفكرة تتلخص في أن الأفراد الذين يتمتعون بمتغيرات جينية متفوقة أكثر قدرة على البقاء، والتكاثر، وتمرير جيناتهم مقارنة بأولئك الذين لا يتمتعون بمثل هذه الجينات.

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0 Comments on this paragraph, 4 in all 4 Comments on this article

Michael Public Jun 2, 2015

Its the same trend at every frontier of materialistic science. The further you go, the more wondrous things become until you reach the point where they boggle the mind and can no longer be properly comprehended in the way 'normal things' can. Draw what conclusions you will from this, but denying it not really a realistic proposition.
Peter Kinnon May 27, 2015

Both the neutral and near neutral mutation hypotheses are plausible, if difficult to test. However, neither, in itself is sufficient to explain the observed phenotypic diversity. Or the even greater diversity of cell types within an organism.

To account for this we have to turn away from the obsession with the genome and instead think in terms of the network of which it is but a small component.

The important aspect which is overlooked, or glossed over, is that the "turning on" or "turning off" of a gene is a function of the cell and not directly attributable to the genome itself.

The very common notion that "DNA creates the organism" is very wrong. Implications of this kind can all too easily help propagate the myth that structural and behavioral changes are driven by the gene (or group of genes) rather than by selection pressure, a function of the overall evolutionary network.

It is important to bear in mind that the genome is merely a rather small library of protein recipes. It is entirely passive. It is actively manipulated, maintained and accessed by RNA and other cellular machinery.

Machinery that is directly inherited, complete with RNA, organelles, the transcriptome, and all other structures required for function. All as a result of cell division. DNA being merely a rather small reference library that is accessed for instructions for the manufacture of “spare parts”.

In my writings I employ the analogy of a piano to represent DNA. The piano itself is entirely passive, as is DNA. But a pianist can produce innumerable musical variations by using this passive array of strings.

In biology, the pianist corresponds to the machinery of the cell together with the inputs from its environment. Some of which control differentiation.

Biological evolution is, after all, a network function.

The network model of inheritance and morphogenesis is explored more fully in my latest book "The Intricacy Generator: Pushing Chemistry and Geometry Uphill", a 336 page illustrated paperback now available from Amazon, etc

Also of great relevance to this topic is Franklin M Howard's excellent "The Way of The Cell". A "must read".for anybody interested in such matters
- Edward Ponderer Jun 1, 2015
  
  I find myself in basic agreement with Peter Kinnon and Zsolt Hermann--but I must take it further to more critical conclusion.
  
  Just to add to the mix, we cannot ignore even wider and deeper observation which further enriches the truly primordial soup of network interaction in which live was born and developed—as it were a child in the womb protected from the mathematical ravages of entropy (in terms of both Shannon’s information and Kolmogorov/Chaitin algorithmic information’s—the development of both fuel and the system of mechanism utilizing that fuel).
  These begin in entering the linear domain of physics, as it were subliminally (and I use this psychological terminology with tentative caution, but nonetheless, purposefully) to the nonlinear interactive domain of curved spacetime. Here information is not communicated in time across space but in similarity of unifying general form across differences in specifics. That is we have transitioned in a rapid statistical sense from the domain of spacetime causality into one of object-oriented tree with branches inheriting from roots. This point, and its importance in finding our way to complete structural/dynamic (position-momentum “phase-space”) subsystems, at least at the atomic level and back to the very hierarchies on the path to a very specific set of broken symmetries (per the Noether theorem, identical with physical conservation laws), cannot be overlooked. Again, it is a statistical phenomenon—it shouldn’t go away entering into the nonlinear domain but rather become a subtle (again I would say, subliminal) background behind the scenes of our observed world.
  This subtlety, in its stabilizing unity, we already know, does not merely cast itself upon the solid state crystal or the resonance of the benzene ring, but works its way in tunneling mechanism (as discovered in 2006) into the very enabler of the enzymes of life’s very evolution and homeostatic sustainment ratchet --at the cellular level certainly. What level of feedback effect has this—allowing linear rather than logarithmic advancement into exponential complexity of the biomass at only the pre-dawn of the survival-of-the fittest principle? This, especially if we fully were to account for the watering-down (smoothing and platokurtic) effect on that principle of the diverse mix of near neutral mutations under a sequence of random environment, short-term epigenesis reactions representing longer time scale entropy, and different fitness requirements across surface-to-volume -ratio limited scales of component-in-subsystem and sub-system-in-larger-system.
  Consider, too, the growing body of evidence of communication and cooperation (internal, emergent intelligence) from this very pre-dawn in terms of altruistic organization of loose associations into full communities and higher being. This, in reaction to growing environmental crises—in short, chaotically varying environmental conditions threatening homeostasis. As analyzed decades back by Robert Shaw (then a graduate student), one of the pioneers of the nonlinear sciences department at the University of California, Santa Cruz, due to the “fractal orbit” signature of deterministic chaos in phase space, chaos actually represented a breaking of the scale-barrier in terms of communication of information.
  We must take specific note of the "4th pillar" of evolution, natural altruism. From the bacterial mega-colony, to communal rooting systems of grasses, to insect colonies, to school, flocks, and herds -- we see that there is a point where individuals link in an altruistic manner to a group, eventually reaching some higher sense of individual.
  This idea rings in deep accord with the concepts of endosymbiotic theory per Lynn Margulis's 1966 landmark paper, "The Origin of Mitosing Eukaryotic Cells" (The Journal of Theoretical Biology). While at this point, it is only considered established that certain cellular organelles evolved through a prior mutualist relationship formed between cell and viral invader, evidence of such symbiotic development (or "altruistic" in human terms), seems to be present in all of nature per the above -- along with the establishment of unified behaviors, and balance become the homeostasis of greater-self. This continues per the Gaia Hypothesis, a perception shared by James Lovelock and Margulis that has become ever more refined and empirically supported—straight-up into the entire planetary ecosystem.
  The critical idea is crisis. Natural communities reach crisis when at the onset of deterministic chaos. The ones that survive, use exactly this “4th pillar” of evolution, and as such, work together over different levels of organization, with local sensation, group decision, and globally coordinated action. In this, they match chaos’ “fractal orbit” in real-time in the fashion of a phase-lock loop in a radio receiver, or brain entrainment in analogy with modern hypnosis technology. The community forms a higher-order system—or if sufficiently integrated--higher independent being.
  “Fossils” of this are pervasive—including our fractal heart and heartbeat. If the latter simplifies, it’s the surest sign that we on the path to coronary arrest (final simple sine wave to straight-out flat—doesn’t get simpler than that).
  Finally, the ideas put forth by Robert Lanza in his theory of Biocentrism, and Roger Penrose and Stuart Hameroff theory of Orchestrated Objective Reduction, cannot be ignored. The former combines well-established empirical results of quantum mechanics with our astronomically unlikely body of life-supporting physical constants and present life information content to formally introduce a long-standing suspicion of consciousness calling forth the very perceived reality needed to embody it. The latter, which has now achieved empirical verification of 6 out of 20 hypotheses need to firmly establish the theory, proposed mind-brain as the collapse of superposition quantum wave function into specific solution in quantum computation. Putting the two together: perceived-measurable reality, quantum computation and consciousness are one and the same; as per Einstein’s relativity, mass, curved spacetime, and gravitation are one and the same.
  
  Whatever all the above mix means, we must be willing to damn political correctness and separate the clear perception of a vast interactive, multi-scale system complex that has evolved “out there” from an essentially 19th century theory that has reached fatal limits to its power as a model as did its period colleague, Aether Theory and the much earlier Ptolymeic Theory of Epicycles.
  We must re-open our minds to new concepts of first-order theory in evolution and accept the fact that centrally Darwinian-based theories of evolution might well be as inappropriate to the known and suspected complexity of nature as to continue to describe the atom in centrally Platonic solids terminology. Evolution cannot remain in any neo-Darwinian framework of a statistical science, when it cannot not be supported quantitatively by probability and statistics! It can, however, evolve into a science of intelligent feedback that has a true algorithm based upon long range goals and “tunneling” past unsupportable states into complete solutions.
  This is the way that genetic algorithms, neural networks and all swarm-like artificial intelligence work in industry to demonstrably produce actual, useful products and services—not qualitative stories.
  Here as well, we might find the impetus to integral education toward the improvement of atomic human relations. This, because it may be all we need to set in motion a human network evolution that may be all that we need to survive/thrive within the great multidimensional crisis of globalization that now engulfs us all.
- Zsolt Hermann May 29, 2015
  
  Thank you.
  I really like the analogy of the pianist playing on a passive instrument.
  I think as you say since we are always talking about a network the next step will be the conscious recognition how there is no single concert pianist but we are talking about an enormous, universal orchestra, constantly trying to tune to each other, create harmony, "homeostasis".
  
  Then we can easily extrapolate it to global human society as well how our next necessary evolutionary step should be creating such a harmonious, mutually contributing, altruistic human cooperation in order to resemble natural systems, positively contributing to the total system instead of harming it like today.
  
  What is beautiful about it is that humans have to become such intricate, integrated parts of the system consciously, against their inherently "cancer-like" nature making them potentially the mind of the whole system, more and more precisely reading the musical notes, understanding the symphony of life so to speak.