Chemical evolution:

Discussion in 'Biology & Genetics' started by paddoboy, Aug 7, 2020.

  1. Traverse Registered Member

    Messages:
    74
    Nobody's said that the postulated populations of RNA-type oligomers in the RNA World would've had to have been similar in sequence; so Darwinism could have pertained in such a population, yes or no?
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. Write4U Valued Senior Member

    Messages:
    16,170
    I believe that the ability for duplication is a fundamental requirement for living organisms.
    But cell duplication can occur via self-replication in almost all life.

    via Mitosis
    https://en.wikipedia.org/wiki/Mitosis

    Please Register or Log in to view the hidden image!



    A protein that self-replicates
    Not just an RNA world
    https://www.sciencedaily.com/releases/2018/02/180227111646.htm#

    Self-replicating nanostructures made from DNA

    by Heather Zeiger , Phys.org

    Please Register or Log in to view the hidden image!



    https://phys.org/news/2015-05-self-replicating-nanostructures-dna.html

    or binary fission in RNA based life.

    Difference Between Binary Fission and Mitosis
    Reviewed by: BD Editors , Last Updated: April 24, 2019
    https://biologydictionary.net/difference-binary-fission-mitosis/#

    Binary Fission

    Please Register or Log in to view the hidden image!


    Binary fission is the process of asexual reproduction (cell division) which takes place in prokaryotic cells, like bacteria.

    https://sites.google.com/site/sacebiologystage1/home/reproduction/binary-fission[/quote]
     
    Last edited: Jan 23, 2021
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Write4U Valued Senior Member

    Messages:
    16,170
    Is it possible that several of these separate paths may have led to life forms?

    Is that perhaps why the Octopodia family is so different from all other life?
    Is this why Flora is so different from Fauna?

    Is it possible that abiogenesis is not a rare event at all but that there have been several paths that led to different forms of life? Each path following it's own evolutionary development via natural selection, depending on it's own unique bio-chemical environment?
     
    Last edited: Jan 23, 2021
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Write4U Valued Senior Member

    Messages:
    16,170
    Darwinian evolution via natural selection focused primarily on biology of survivorship to procreate, whereas generic evolution and natural selection covers the entire physical spectrum of functional refinement and durability.
     
  8. Q-reeus Valued Senior Member

    Messages:
    4,167
    No, you keep asserting things as though proven fact when they are not.
    The mousetrap argument is a limited analogy that breaks down if pushed too far reductio ad absurdum. Even so, Behe covers your example given by someone else and explains it's shortcomings as already linked to back in #888. The link again: https://idthefuture.com/1391/
    Relevant section is from ~ 11 minutes to 18 minutes mark. The real world prebiotic situation has to posit enormously more complex molecular arrangements as minimum viable living entity.
    And as per last part of #888, there can imo be no Darwinian path to a fully functioning cell that without that integral membrane is hopelessly fragile against environmental poisoning.
     
  9. Write4U Valued Senior Member

    Messages:
    16,170
    What poisoning? Where does the poison come from? Why do you assume a self-assembly must be fragile?

    How can the membrane even form unless allowed to do so by its environment in the first place? Once the membrane is formed it becomes very resistant to external pressure.

    Surface tension of a compound chemical bubble can be extremely resistant to invasion and also offer great protection for anything fragile located inside.

    Please Register or Log in to view the hidden image!


    https://www.sunnysports.com/blog/walk-water-humble-water-strider/

    Laplace's Law
    The larger the vessel radius, the larger the wall tension required to withstand a given internal fluid pressure.

    Please Register or Log in to view the hidden image!


    For a given vessel radius and internal pressure, a spherical vessel will have half the wall tension of a cylindrical vessel.

    http://hyperphysics.phy-astr.gsu.edu/hbase/ptens.html#bal

    Self-assembly

    Please Register or Log in to view the hidden image!


    Self-assembly of lipids (a), proteins (b), and (c) SDS-cyclodextrin complexes. SDS is a surfactant with a hydrocarbon tail (yellow) and a SO4 head (blue and red), while cyclodextrin is a saccharide ring (green C and red O atoms).

    https://en.wikipedia.org/wiki/Self-assembly
     
    Last edited: Jan 24, 2021
  10. Q-reeus Valued Senior Member

    Messages:
    4,167
    You have no understanding of the real issues involved. It's been explained before - no use repeating it here only to have to do it again and again.
     
  11. iceaura Valued Senior Member

    Messages:
    30,848
    1) Too complicated, too dependent on biological context, and currently operating at a second or derivative level in biological organisms without otherwise existing or being closely related to otherwise existing chemical complexes. They appear to be later developments, in other words, closely fitted to a context of living beings as we know them.

    2) As far as we know they are unnecessary in abiogenesis.

    As they are both complex/complicated and probably unnecessary, assuming them seems far too likely to mislead.
    I claim basic comprehension, not familiarity with minutiae, of Darwinian theory (not sure about "Darwinism").
    Darwinian evolution is an inherent pattern of the changing material universe - a similar question might be at what point one imagined Copernicanism beginning.
    Biological evolution of currently living beings, things with populations of alleles, can be defined that way if one is very careful.
    Evolution of other kinds of things would be defined differently.
    Natural selection is a category - a very large and diverse category - of "drivers". It includes, for example, chance events and stochastic influences.
     
  12. iceaura Valued Senior Member

    Messages:
    30,848
    It is a crass error that reveals a basic misunderstanding of Darwinian theory.
    You have nowhere near enough information to make such an extraordinary claim, even as a guess.
    On top of that vast ignorance, which you share with everyone, your continual reposting of Behe's elementary irreducibility mistake demonstrates that you do not know what a Darwinian path is.
     
  13. Q-reeus Valued Senior Member

    Messages:
    4,167
    The infamous tactic 'you are stupid' doesn't work on me.
    I say you have no clue as to how an integral cell membrane (with all that implies a la #888) could ever form. The DETAILS! It all HAS to happen in one cell lifetime, or never. And it's never.
     
    Last edited: Jan 24, 2021
  14. iceaura Valued Senior Member

    Messages:
    30,848
    Of course not. That's why Schmelzer assigned it to me - it's in his comfort zone, and yours, that's why you borrowed it.

    Schmelzer finds it easier to handle than the contents of my posts - for example, it's much easier to handle being called stupid than facing the observation that you don't know anything first hand or authoritatively sourced about Darwinian evolutionary theory - like Schmelzer parroting the wingnut feed on some scientific matter, you've never studied it, and you know that you have never studied it. Everything you post about it you got from websites like the ones you've linked here - the wingnut feed on Darwinian evolutionary theory. (How do I know? Common error and common vocabulary).

    Since that is the case, you will readily comprehend - as has been explained to Schmelzer and the rest of the Republican media feed victims here enough times that further incomprehension is demonstrably willful - that none of my posts are intended to "work" on you, but rather (note that my post was a summary repetition)

    1) repeated correction of error for the benefit of the driveby reader and possible victim of uncountered repetition (a lesson learned finally and for all from the national US elections of 2004)
    2) mockery. It's the approach that seems in my life to have best hampered the authoritarian, and especially the rightwing authoritarian. ("Boiling over the fire, rising out of belief, and falling, like a tyrant, out of derision alone" Hoover: 'Dry Bones' ).
     
  15. Q-reeus Valued Senior Member

    Messages:
    4,167
    Oh wow finishing off with dramatic prose quote from Hoover. Stunning. But I noticed not a word dealing with my late edit. You know, actually offering a plausible Darwinian step-by-step path to a fully functional integral cell membrane. Necessarily happening within a single cell lifetime. So you have a good grasp of the power of Darwinian evolution? Enlighten my unbelief then in the Power of Darwinian evolution to accomplish that essential task! Actual details - not vague hand-waving hype.
     
  16. Write4U Valued Senior Member

    Messages:
    16,170
    your explanation is naive and misguided. I do have an understanding of the issues involved and I am telling you you are wrong. In the absence of a definitive theory, my interpretation is much closer to reality than yours. You should avail yourself of some of the links I provide, instead of ignorantly dismissing my research in the subject.
     
  17. Q-reeus Valued Senior Member

    Messages:
    4,167
    Your interpretation is out in imagination land. See my previous post. That invite is open to anyone here, even chronic posters of eye candy You Tube vids having marginal relevance at best.
     
  18. Write4U Valued Senior Member

    Messages:
    16,170
    You are so hung up on "irreducible complexity" you just cannot compartmentalize the abiogenetic processes.

    What you do not understand is that the left-handed amino acids are used in the development of metabolics, and the right-handed sugars are used in the development of RNA and DNA genetics. These are separate processes and need not have occurred at the exact same time.

    To use Behe's mousetrap, each part of the mousetrap must be manufactured separately before it can be assembled into a functional whole, a detail that is so conveniently overlooked.

    My interpretation is from reliable sources. You may want to read some of it.

    Genesis: Rocks, Minerals, and the Geochemical Origin of Life,
    Robert M. Hazen, Guest Editor 1

    METABOLISM AND GENETICS
    https://hazen.carnegiescience.edu/sites/hazen.gl.ciw.edu/files/ElementsIntro.pdf

    and

    The Informational Substrate of Chemical Evolution: Implications for Abiogenesis
    Andrés de la Escosura1,2

    Abstract
    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6789672/
    [/quote]
     
    Last edited: Jan 24, 2021
  19. Traverse Registered Member

    Messages:
    74
    Poppycock, Monsieur. They merely appear to be "too complicated" and frustrating for you to be able to readily conceive of a mechanism for their primary CE origination.

    And they're both primary & central to all of Biology, as you ought well know; there's nothing secondary or derivative about them, at all.

    You're just frustrated with them because at the moment they merely seem to be abiogenically inconceivable & incomprehensible to your clearly quite limited grasp of Chemistry.

    Your wholesale lumping of NAs as 'downstream' in the entire CE story merely relieves you of having to concern yourself with something which your mind doesn't have either the requisite knowledge, background, or the steeled patience, perseverance, & persistence to face up to.
     
  20. Traverse Registered Member

    Messages:
    74
    As you seem to be afraid to admit, the RNA World model actually solves both the genetic & the catalytic root problems of all of CE in one go. It'd found all of Biology on the Earth in a unified way. Just because the NAs appear to you to be too complex for your own mind to be able to conceive of any possibility of a plausible origination for them on the early Earth, don't presume to mislead others by so dismissively discounting the NAs out of hand.
     
  21. Traverse Registered Member

    Messages:
    74
    As you must well know, but have tried to adroitly avoid admitting, Darwinism essentially requires genetics, and therefore it requires some kind of a genetic oligomer. So if you're dead-set against letting NAs into the CE story until later on, are you positing that proteins/carbohydrates/lipids fulfilled that role early on?

    As a purportedly bio-educated person, you'll simply have to admit that having NAs in the beginning would make comprehending Biology ever so much easier.

    Copernicus is a red-herring here, so you'll have to do better than that in order to obfuscate the discussion from the reality that Darwin's genius could easily have 'kicked-off' in the RNA World conception.
     
  22. Traverse Registered Member

    Messages:
    74
    And as for above insistence on some kind of supposed fundamental CE problem with prebiotic membrane formation, I'd recommend that those arguing for any such difficulty in the prebiotic context go to their local library to borrow a book on Surface Chemistry, in order to have the scales promptly drop from their eyes. An enormous amount of work has been done in that area, which clearly makes prebiotic membranes a given at this point. So prebiotic cellularisation isn't a difficult issue, at all.
     
  23. QuarkHead Remedial Math Student Valued Senior Member

    Messages:
    1,717
    I'm afraid this is a non sequitur. Genetics works, in fact did work, just fine without any knowledge of the molecular structure of genes.
     

Share This Page