Denial of evolution IV

Discussion in 'Biology & Genetics' started by Hercules Rockefeller, Oct 27, 2009.

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  1. Skeptical Registered Senior Member

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    Zen

    One of the things that creationists so often fail to appreciate in arguments on evolution is the sheer amount of time involved. Life has been on Earth somewhere between 3 and 4 billion years. The time involved is literally beyond human conception. We cannot envisage one million, let alone a billion.

    This makes your argument about small changes quite invalid. Certainly mutation and genetic recombination variations are mostly quite small. However Silbury hill, a prehistoric grave site, at 40 metres high, 2 hectares area, and over 200,000 tonnes, was built by individual men carrying baskets of dirt up the hill and dumping them (500 men for 15 years estimated). Small changes over a long period equal massive net changes.

    If, every generation, a tiny genetic change happens in a population, then over trillions of generations, we end up with a total change that is massive and profound.

    On fossils, again. Paleontologists now have amazing dating techniques, which can usually place a bed of fossils in geological time. So each type of fossil will be known to be of a certain age, plus or minus an error factor (usually under 5%).

    The progression of changes in the fossil record across time fit very nicely in the time line for evolution. For example : Archaeopteryx precedes true birds. The first agnathans preceded the jawed fishes. Shark relatives preceded bony fishes.

    It has been said that evolution would be easy to disprove. Just find a rabbit fossil in Precambrian sedimentary rock. That has never happened. Any fossil way out of its time line would cast the same level of doubt. Again, apart from a few obvious hoaxes, that has never happened.

    Evolution has no direction, and no motive. But there are, nevertheless, overall trends which can be seen over time.
     
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  3. iceaura Valued Senior Member

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    Not from that source, please. That is just abusing the forum - there are several fairly well informed people on most topics around here, who bring the possibility of actual discussion, and your creationist blogs have made themselves very tiresome. It's like the frequent attempts by students to get people to do their high school homework for them - eventually, you will be simply brushed off.
    If you keep on reading those creationist blogs, you will keep on spamming the forum with bs you don't know anything about.

    The nature and origin if chirality in organic compounds is an interesting topic, with a lot of attention paid to it over many years now, and if you are actually interested you can quit wallowing in creationist bilgewater and search out some of the many sources of information and insight and so forth.

    Actually do some of that "research" you claim to have, but obviously have not, done.
     
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  5. Believe Happy medium Valued Senior Member

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    It is definitive, in fact it's chemistry. Lightning fixes nitrogen, this is not up for debate.
     
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  7. Zenithar66 Registered Member

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    TOPO(I actually got banned from that ask a biologist forum for asking these exact qu)



    how do you less efficeintly cut a phosphodiester backbone?
    and could an organism survive such lack of efficency?
    far too much specualtion i feel.

    of course i see the potential for gradual changes! but i dont see how you can just say "as DNA maintanance machinery gradually becomes more efficeint" without stopping and think of the sheer number co evolvign enzymes we are talking about here for the improvement of efficiency!!

    topo, to me so far, defies evolutionary mechanisms, it seems like the only way we can fit them into it is by saying it does...
    (and i know its in the past but my future posts will include MUCh form the present)

    I am open(and that is the truth, i have a policy of self to be open minded, becuase at teh end of teh day, holding onto what you think is right simply becuase it fits your worldview or brings you comfort is not a honest life at all and it is a sign of a childish mind that cannot accept change).......what i was saying was i am open to my mind being changed on the matter
     
  8. Zenithar66 Registered Member

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    80

    Indeed it is, i was naive about the issue, very intersting and again demonstrastes the amazing cycles of nature!
    of coures one can truly only speculate about such issues
     
  9. Zenithar66 Registered Member

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    yes and that is that things change over time, hardly need a thoery to tell us that do we?
     
  10. iceaura Valued Senior Member

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    30,994
    The theories involved account for the patterns in the changes, in the traces of the past changes, and so forth.

    If you care about understanding them.

    But since you don't, and are simply engaged in abusing the forum with bad faith objections to things you don't bother to honestly consider or comprehend, the insights available from the great theories of life on earth are not available to you.
     
  11. Pete It's not rocket surgery Registered Senior Member

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    Hi Zenithar,
    Try this.
    Here's what a short quoted post would look like as I construct it. The black text is given by the

    Please Register or Log in to view the hidden image!

    button. The red text is what I would add in:
    Code:
    [noparse][quote="Zenithar66, post: 2773803"][/noparse]im not quite sure i understand your reply? if your
    asking does it cleave the genes then no, it simply cleaves the phosphodiester
    bakcbone of the DNA duplex.[color=red][noparse][/quote]
    Kind of the same thing, though. It cuts the DNA strands that genes are made of,
    right?
    
    [quote][/noparse][/color]Oh, and then re seals it of course![/QUOTE]
    [color=red]Interestingly, type Ib topoisomerases do this passively, without any ATP, and
    without controlling both sides of the cut.[/color]
    [noparse]See how I type "[/quote]" after the section I want to reply to, then "
     
  12. iceaura Valued Senior Member

    Messages:
    30,994
    From an evolutionary perspective, there was no very first time that DNA supercoiled.

    So your entire approach there is irrelevant, because you haven't bothered to acquaint yourself with the basics of the topic you are attempting to discuss.
     
  13. Pete It's not rocket surgery Registered Senior Member

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    10,167
    Hi Zenithat,
    The conversation has become unwieldy already, so I'll summarize;.

    First, here's my amateur understanding of topoisomerases and their function:

    - Type II topoisomerases are complex protein machines that untangle supercoiled DNA double helices by cutting and rejoining both strands of the double helix. Type II topo uses ATP.
    - Type I topoisomerases are complex protein machines that relieve twisting tension in a DNA double helix by cutting one strand and allowing or encouraging the double helix to unwind before rejoining the cut strand. This helps to avoid supercoiling. Type I topo uses no ATP.
    - DNA can be replicated without topisomerase if it is not ring DNA, and if it is not bound to another structure like a histone. I suspect that the length of the chain is also relevant, with supercoiling likely to result if the chain is too long (how long? dozens of full turns? hundreds? thousands?) I think that the longer the double helix, the more likely it is to build up twisting tension to the point of supercoiling.

    Enzymes in general:
    - The efficiency of an enzyme is measured by how many reactions it can successfully catalyse per unit time. See Enzyme activity
    - The enzyme's efficiency depends on its affinity for its target, its specificity for that target, the chance it has of performing its function before letting go, and it's ability to let go once its function is performed. There's a lot of randomness in chemistry. Enzymes often aren't the perfect machines they're imagined to be.
    - A particular function (eg that of a topoisomerase) can often be performed by an enzyme with a different apparent purpose (eg RNA enzymes can also have affinity for DNA)

    Evolutionary science concepts:
    - The last common ancestor means the most recent shared descendant. Eg, the last common ancestors of me and my cousin is two of our grandparents. So last common ancestors are not original forms.
    - Evolutionary biology does not rely on a number of codependent functions appearing simultaneously.

    Enzyme evolution:
    - New improved enzymes are (almost?) always slight modifications or combinations of existing enzymes
    - The first organism to use a new improved enzyme does not need it. Ie the new enzyme makes an existing process more efficient.
    - The first organism to use a new improved biomolecular process does not need it. Ie the new process makes the organism more successful.
    - The first time a beneficial new biomolecular process occurs is always a serendipitous result of existing mechanisms.
    - From then on, marginal improvements in the process drive marginal improvements in enzymes, always with the possibility of serentipitous new processes emerging from interactions of existing enzymes.

    And science in general:
    - Speculation is a natural and necessary part of scientific investigation, along with subsequent investigation of the compatibility of speculations with observations.
     
    Last edited: Jun 30, 2011
  14. Pete It's not rocket surgery Registered Senior Member

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    Summary of the summary:

    The first organism to use a topoisomerase did not need a topoisomerase.
     
  15. Zenithar66 Registered Member

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    reply



    can you at least tell me why there was not a first time dna supercoilded?
    since dna obviously do ot from its inception, surely it would have too have done so fir the first time at some point. And my whole approcah is not irrelevant since that is not my only approace. Im trying to find out is the evolution of this enzyme via evolutinos mechanisms plausible. thanks
     
  16. Zenithar66 Registered Member

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    80
    If i got the quote thing wrong sorry!!


    yes, but infact certain topo 1's do need it to stimulate its function as i read here..http://www.ncbi.nlm.nih.gov/pmc/articles/PMC554563/ at the beginning of the abstract!. and of course we cannot overlook the fact that(and i havent found the reason anywhere, maybe we simply don't know?) it has to arrive "on site" at the right times during the cell cylce and after it performs the nick in DNA it must then at the end of replication seal it at the right time. do you have any idea how topo's are transfered to the sight needed?

    And of course, whether or not the first gyrase needed energy is besides the point, what iceaaura(user) doesnt seem to understand is there indeed must have been a first time DNA supercoiled, and if, as you say, topo may have come from a modified enzyme that perfomred other functions, is it realistic to suggest that this was co opted at the "right time".[/quote]














    first off, I'm obviosly not alluding to DNA's that do not need a gyrase function(though i havent personally come across that yet).
    it wouldnt actually be so much down to the size of the helix or how many turns(that certainly would have an impact), but even short dnas need first to be opened up ahead of the replication fork by helicases for access to bases, and its the action of these helicases before and behind the replication fork that actually brings the need for topo, becuase as they unwind ahead, supercoiling insues further still ahead, and topo is then "recruited" at a particular point in the cell cycle!
    Indeed without topo 2 chromosnes would not be able to untangle before replication, so do we suggest that the first replicaing chromosomes of considerable density just happened to have topo 2 at the ready?











    first off, i would highgly suggest not to keep using wikipedia as your main source as i have found it very unreliable on many many issues and would rather look at a textbook or available paper. Of course i always check wiki anywho because it is still full of much correct info i simply wouldtn rely on it thats all!

    when you say theres alot of randomnes to chemistry, that is true, but the cell is a quite different ball game, it is ordered beyond belief, The cell cycle alone is enough to make one awe at the startling solutions, accuracy, efficiency(proteins are recycled and reused!), timing, co ordination and maintanance present within. Yes, the cell is not simply chemistry, it is orderd to an extent far beyond what we could have ever imagined looking through our early microscopes!! it is like a city among a landscape, made of the same stuff, but clearly highly ordered, specialised and purposeful, so i dont really see your remark as relevant.

    Do you think there is randomness in the perfecly timed separation of sistar chromatids at the correct time in teh the cell cylce? or that, in order for this to occur, the cohesins holding together the chromatids must be destroyed by other multisub enzymes at the exact right time for replication to happen at all? this is not random chemistry, but, somehow, a cosmically ordered symphony of endless parts! and no I'm not inferring god, just that a huge mystery confronts us!!







    yes i know, thats why i said the last common ancestor of archea and bacteria, do you think what you said makes it anymore likely for a gyrase function was present in this early organism?



    well I havent yet studied the evolution of enzymes as much as function so I'll have to look into that! That doesnt make the corectly timed modifications any more viable to envision the then the creationists model since your stil relying on pure chance events to coincide with "need", when i say taht i mean it in a mechanical abstract sense. it "needs" somethign at a particular time otherwise replciation cant continue.







    it seems like your talking from experinece? have you seen this occur?
    I think you are simply stating evolutions predictions here but i could be wrong,



    [/quote]And science in general:
    - Speculation is a natural and necessary part of scientific investigation, along with subsequent investigation of the compatibility of speculations with observations.[/quote]

    indeed it is, and i would never disagree, only with overextendiNG those powers and participating in pure imagination.
     
  17. Zenithar66 Registered Member

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    80
    Hmmmm


    WOW, i honestly didnt expect this kind of close mindedness here, i made it quite clear that i am neither a creationist nor tryign to disprove evolution. Only to question it and to learn and challenge my own beliefs, becuase if i am not debated i will just go on comfortably believing such and such without other opinions on the matter!


    I do not make "bad faith objections", i simply see the evidence and question it, like we should all do! if I can be convinced i am happy to be so.
    and to assume I havent studied it is a huge mistake, since i am indeed and have been engaged deeply now for over a 2 year period.
    again, you have neither rebutted nor explained anything, rather you have taken a lazy way out, so i hope you will reconsider your views about me and your reply.
     
  18. billvon Valued Senior Member

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    21,635
    It's not blind. It goes in a very specific direction, the direction which allows animals to produce the most offspring.

    I don't get this. I mean, sonar is certainly a "blind" process; it has no goals and no intent. But bats navigate quite well using it.
     
  19. Zenithar66 Registered Member

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    80
    ,..

    huh? thats not exactly an analogy for a long process of blind modification?
    and waht do you mean its "not blind"? it has no goal and no direction, only results? the only direction it could have is the abstract ones you apply to it.

    but anyway, its a mincing of words and the fact is evolution is blidn in the sense that it is unguided.
     
  20. iceaura Valued Senior Member

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    30,994
    It's too complex an arrangement to have appeared in one step, suddenly, from no precursor behaviors or arrangements.

    At least, that's what evolutionary theory grounds on. If you are discussing evolutionary theory, you begin by understanding that it specifically excludes the necessity or likelihood of a "first" anything complex.
    Not according to evolutionary theory. There is no "inception" of DNA, no "first time" for things like supercoiling, and so forth.
    It is your whole approach here. And it reveals that you have no idea what the Darwinian theory of evolution states, or how evolution works according to its formulations. So you have no hope of determining its plausibility in any situation, let alone one like this.
     
  21. iceaura Valued Senior Member

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    30,994
    You are abusing the forum with creationist bilge. I don't really care what label you apply to yourself or the many, many other people who have come here and done that. It's rude, and mindbogglingly arrogant. Do you think you are the first? Go to some site like talkorigins, and you will find everything you have posted here in their FAQ file.
    No. You simply regurgitate garbage from creationist blogs. You see nothing for yourself, and do not comprehend the nature of "evidence" in the discussion of matters you do not understand.
    You have posted nothing here but nonsense and silly mistakes we all recognize from creationist websites. You quite obviously have not studied evolutionary theory - it is not found on the creationist blogs that are your only sources, for one thing, and you keep making very basic, rock bottom, simple errors in description and analysis and assertion, for another.
    As long as you do that elsewhere, no loss. What you are doing here is not "debate", and I see no reason to pretend you are actually here to learn anything.
     
    Last edited: Jun 30, 2011
  22. Trippy ALEA IACTA EST Staff Member

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    Again, this issue is a non-starter.

    Carbon rich meteorites have been found to have an excess of L-Enantiomers over D-Enantiomers in carbon rich meteorites, and there are several explanations that have been proposed for this observation - including circularly polarized light as a result of supernovae.

    However, recently, the observation was made that the greater the enrichment of L-isovaline in these meteorites, the greater the amount of water alteration that appeared to have taken place. This is important to note because, at least in the case of isovaline, L-isovaline is slightly less soluble in water than D-isovaline.

    Here is a paper from 2009 discussing the discovery of excess L-Isovaline in the Murchison Meteorite and the Orgueil Meteorite.
    Enrichment of the amino acid L-isovaline by aqueous alteration on CI and CM meteorite parent bodies

    And here's a NASA press release (there will be a paper associated with it somewhere, I simply lack the time to track it down) that exteds the initial findings to a wider range of meteorites.
    More Asteroids Could Have Made Life's Ingredients

    So, like the fixable nitrogen issue, this issue is a non-starter. You'll also note that there's an extra added layer of parsimony in all of this (to put it one way) in that the excess of L-Amino acids has come from the same source as the ammonia - indeed, they've both been found in the same meteorite.
     
  23. Zenithar66 Registered Member

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    ...


    the nitrogen thing, your right, from my ponint of view it seems to be one less issue to contend wtih in terms of abiogenesis!(not that i have yet seen anythign plausible).

    but the chirality question is a whole lot stranger and much deeper.
    That metorite was an excess of left over right, what does that prove, ti shouldnt be used as evidence for anything. How does having a slight excess mean that you will end up with 100 percent, but the strangest thing is that its ALL left for dna and ALL right for amino acids(or vice versa)..and even putting in a left to a right system can prevent proper folding of proteins.

    I am no expert on this issue yet, but i simply have seen no real explanation. I really dont see what this meteorite is supposed to prove becuase even in the theoreticl prebiotic soup we would not see exactly 50 50 R and L, there would be concentration gradients, but nothing that is 100 percent.
     
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