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Are we byproduct of cell's survival scheme?

  1. Jun 28, 2006 #1
    *im not sure where to put this thread*

    Given that we are evolved from a single cell(bacteria/organism) due to its struggle for survival (which i have no idea why that cell would wanna do that?), why is it we do not accept that we are just a way for cells to survive in evolutionary struggle?

    explanation: multicellular bodies formed due to evolutionary advantage of protection and food acquisition. Further down, a cell specialization formed to be even more efficient in struggle for survival. Even further down, different species of specialized cells "learned" that simple form of cooperation may be even more potent for survival. Well, we get the picture. Well, is it possible to extrapolate that cells "evolved" a decision specialized cells which takes care of high level decisions where to look for food and carry out this survival struggle and which we would call brain?

    in this picture, the cell is THE entity that procreates. We/or any animal/plant, is just a "body" of cells that learned that this way they ensure their own level of survival. In other words, we (as bodies) are the 'technology' that cells invented to help them in the survival. Given that in our (human) case, only 1 cell matters (sperm and egg) all others are discarded after given enough time to procreated and pass on the DNA that will ensure new ONE cell that matters.

    i dont wanna make it too long, but there is quite astonishing facts to be realized from this point of view. I would like to see, if there is something inherently implausible in this view point? Its limits, strengths, meaning.....?

    I came to this craziness after reading a book "sex and the origins of death" which by my opinion is profoundly thought provoking in the matter of death and sex (as one would not expect ).

    sneez
     
  2. jcsd
  3. Jun 28, 2006 #2

    DaveC426913

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    Read 'The Selfish Gene'.

    "...an organism is DNA's way of perpetuating itself..."
     
  4. Jun 28, 2006 #3
    its on my list 'to-read'

    so basically my lyman understanding and wording of that concept is scientifically accepted ?
     
  5. Jun 28, 2006 #4

    arildno

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    It is more correct to say that within a unicellular environment, there will be ecological niches fillable for multi-cellular organism, and hence, some such multicellular experiments might prove itselve to be successful adaptive strategies.
     
  6. Jun 28, 2006 #5

    selfAdjoint

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    There are two ways for one unicellular organism to encapsulate another - by eating it and by being infected by it. Once the second organism is inside the first, if protected from dissolution in some way, it can affect its host's lifestyle, metabolism, and reproduction. It is thought that this is how eucaryotic cells acquired their organelles and nuclei. Once you have stable nuclei governing reproduction, they can evolve like anything else, and simple reproductionof some genetic material can produce multi cellular offspring. If these survive, they too can evolve, and there you go.
     
  7. Jun 28, 2006 #6
    Speaking of selfish genes, it looks like selflessness also has its benefits in evolution:

     
  8. Jun 28, 2006 #7
    now obvious question thats is mind blowing for me: why would DNA want to "procreate" ? How does a mindless matter out of chance decide to form 'most' complex thing (DNA/genes) which for some reason has to exploit mindless matter to keep just existing.

    the only explanation i can think of is that matter is not mindless. WEll, that does sound out of all the boxes possible.

    Do we know what gene is responsible its own selfishness? do we have a theory how it evolved ?

    from the gene point of view, it look like we are the mindless and 'he' decides what to do with us :d while keeping us under illusion of control.
     
  9. Jun 28, 2006 #8

    arildno

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    It doesn't want to procreate, neither is it selfish.
     
  10. Jun 28, 2006 #9
    how do you explain a virus? why would a virus want to 'multply' ? it has no attributes of life as we understand it. Its just DNA with protein coat.

    the quesion is WHY/and HOW would a lifeless matter (such as in primodal soup) which formed by accident into more complex structure get into the cycle of multiplying? Why would it invent death? (which is part of evolution) there is nothing inherent in life which should predict death from lifeless matter.

    plz if you could answer or give more reasonable comment on these question rather than stating some ultimate thruths....
     
  11. Jun 28, 2006 #10

    selfAdjoint

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    Quite right; a virus is just a little chemical machine. But if you imagine it came into existence from a cell's DNA being spun off, then one of two outcomes happens;
    1) The virus is able to enter a cell and use the cell's metabolism to make copies of itself (this after all is what "proper" DNA does, and at least some examples of "rogue" DNA would possibly retain the capability). In this case viruses with this capacity are reproduced.
    2) It doesn't have this property, doesn't reproduce, and is never heard of agiain.

    Those that can make cells reproduce them can now evolve, and the host cells can evolve to resist infection, and you have a "Red Queen's race" in which predator and prey evolution is linked and the whole business of selection is vastly speeded up.

    Bottom line; the virus doesn't "want" anything. It just does what it is built to do, and it is built that way because of its evolution.
     
  12. Jun 28, 2006 #11
    thanx for further clarificatoin selfadjoint

    however, do we have understanding (as humans) or why DNA has the ONE goal - reproducing itself?

    In human perspective: once a reasonable number of our germ cells have been given a chance to impart their DNA to the next generation, our somatic cells (our bodies) become excess baggage which serves no useful function for DNA anymore, then we die so that change can be transmitted further down.

    Its under the guidance of DNA that every somatic cell in the body will senesce! and ultimatelly die on its own. If our somatic cells escape accidental death, they will ultimatelly be instructed to comit suicide (programmed death) by DNA.

    It seems nature recognizes no hierarchy among somatic cells. (unlike us who think of brain cells as the most important to the extent that we define death by it). WHy do we make such distinction when nature does not?

    The brain evolved to coordinate the activities of the body more effectivelly, to make the organism it directs better at competing for resources, for survival and for the righ to pass on a particular set of genes (DNA). Is it that somewhere along the way the human brain took a competelly unprecedented turn and acquired MIND? Does this mean anything to nature? It has NOTHING to do with survival. Our amusements, poetry, soap operas, arts,......

    How come it seems that nowadays the pressures that govern our own further evolution are not longer STRICTLY biological? Human beings escaped natural selection?

    Our brains are driven by DNA- mindlessly , yet, somehow DNA desperatelly "WANTS" (for lack of better word) reproduce itself. The evolution is about DNA.

    my question is why would mindless matter do that? Did it get into deadlock , it just executes commands? Isnt it an example of perpetual machine? given resources it will never stop. DNA will always want to reproduce? WHY? are we just vehicles for DNA? DNA creates our minds which create everything else, including our discussions in philosophy which are for the purpose of DNA useless. why ?

    this line of thought is brand new to me, and im kinda in resonance to place it in my world view.......

    sneez
     
  13. Jun 29, 2006 #12

    DaveC426913

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    The danger you are flirting with is anthropomorphism. When we talk about what structures "want" to do, and 'why" they're like that, we are assigning human properties to non-living things.

    We might as well say that galaxies form because stars are "lonely".



    3.5 billion years of evolution is just too hard to grasp, but if we looked back that far, we would see how DNA could have evolved for no other reason than because of chemistry.

    The structures that first formed might have been from fat-like molecules which have a water-attractive end and a water-replusive end. If these formed into a sphere (just like bubbles form in soapy water), you would now have a volume that is somewhat resistant to having it contents washed away by the whim of every current. So far, nothing but chemistry.

    As you progress through the stages from these very simple forms, it becomes much easier to see how life can have formed from nothing but the tendency of chemistry to form self-organizing structures.

    And 3.5 billion years is a long long time.
     
  14. Jun 29, 2006 #13
    thats exactly what troubles me and we must admit there is no other explanation for it...... [explain in other terms what DNA does, explain why when a cell is about to die it will try to rescue itself either by withdrawing from harmfull environmet or by reparing itself in some other terms]

    but

    WHY would DNA need/want (i dont have a word for it, why does it do what it does) to reproduce itself. Is it living?

    the theory of evolution is based on the need for survival. Why nonliving matter wants to survive? when at the end it will go back to elements anyway (death). is DNA alive?

    as current research shows, life is at its barrest interaction of certain formation/configuratio of atoms and thermodynamic/energy. How come certain configuration of atoms and right amount of energy gives birth to something which "evolves/wants to survive"?

    Lets take agains example of virus. Its nothing but DNA. How do you explain it will keep trying to put its DNA into other cells infinitelly and when the cell learns to protect itself the virus will "figure out" other ways......

    im interested in HOW AND WHY would initially mindless/lifeless matter start this? (do we have a lead in science on this?)

    "And 3.5 billion years is a long long time." - human DNA still rules human life as we understand it. All of our human traits are just byproduct as it appears....it seems it did not change in function only in means ! any thoughts on this..?
     
  15. Jul 2, 2006 #14

    Moonbear

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    It doesn't need or want to reproduce itself, it just happens.

    The theory of evolution is based on the level of species and entire populations of organisms, not on individual DNA strands.

    Can you cite what current research that would be? Life is generally not defined in such simple terms. That definition could make a mineral a life form, which obviously is not.

    You're attributing sentience to something which is not actually sentient. This is what others have referred to as anthropomorphism in your arguments. You're projecting human traits onto things that do not hold those traits. The virus isn't "trying" to do anything. It's just like your TV doesn't "try" to show you certain programs, it just has the mechanisms in it that allow it to do that. What you're missing here is the chance. A virus doesn't "figure out" other ways to get into a cell. If a cell has a defense against the virus, the virus dies. On the population level, if another virion happens to have a mutation that makes it possible to get into the cell and bypass that defense mechanism, that one survives and propagates. If no virus has any mutation that allows that to happen, then they don't propagate, and that strain of the virus disappears, or only infects the cells that don't have the defense mechanism.

    im interested in HOW AND WHY would initially mindless/lifeless matter start this? (do we have a lead in science on this?)

    Not necessarily. DNA just provides potential. Our interactions with our environment help determine whether that potential is realized.


    I get the overall impression that you're just starting to learn about genetics and evolution and are struggling a bit to grasp the concepts. The difficulty you're having is in attributing human qualities to DNA. You're trying to think about it as if DNA itself is thinking. It doesn't. If you instead think about it as just chemical reactions, that when all the right reactants and catalysts are present, it will happen, and if they are not all present, it won't happen, you might have an easier time grasping the concepts.

    Beware of misunderstanding analogies used in popular writing on the subject. It is intended to try to make technically challenging material more accessible, but can also create more confusion than it clears up by misleading the reader.

    Please keep asking questions, and we can continue trying to help clarify your understanding of the subject.
     
  16. Jul 2, 2006 #15
    definitively amateur with curiousness i would label myself. (im student of physcis by day :smile: )

    is DNA alive? (what is it missing to be if not?)

    i will look it up, it comes from a book by w.r. clark "sex and origins of death". There is a bacteria which when food deprived or conditions of her environment not suitable for her life will go to this "mode" as if dead. Its like hibernating. This mode the bacteria is without fluid, only matter. This clump of matter can be brought to nearly absolute 0 for any time period. Then when brought again, introduced into specific temperature and environment will come alive. Scientists had hardest time see how it can be because it does not fit our definition of live. They theoretized that life must be in the arrangement of atoms themselves. Meaning: if we could arrange atoms in the same form as of that "dead" bacteria it should come alive in the right temperature and environment. are u familiar with this bacteria mode?

    im aware and i repeatedly admit i do that, but not because of some hidden agenda of proving my point. As you can see im just asking question in the most basic amateur level.

    why that mutation takes place in the gene that is crucial for its survival? There are thousands of genes which can mutate and nothing will make it survive.

    do not human attributes arise from DNA? The arrangements of each cell and its function, production of hormones, etc is determined by DNA. The cell death is determined by DNA (not the accidental one).

    thats the problem, the way DNA is described to me is, as if it was thinking and that is what troubles me. The things is, that the experiments that are described in the books i read really support my impression that DNA is thinking (or knowing something which it suppose to not know as matter)

    thinking of it as chemical reactions is hard as well for me. As chemical reactions not to just happen or not happen. Chemical reactions can happen in most unpredictable manner in complex chemical environment, especially with feedback loops, non-linear source and loss sinks of reactants, etc. I do not know about comprehensive chemical description of life from individual DNA up to cognitive skills.

    what would be ur responses on this:
    thats exactly what troubles me and we must admit there is no other explanation for it...... [explain in other terms what DNA does, explain why when a cell is about to die it will try to rescue itself either by withdrawing from harmful environment or by repairing itself in some other terms]

    How come certain configuration of atoms and right amount of energy gives birth to something which "evolves/wants to survive"? (this is concerning my "dead" cell described above.....)

    is human life not about passing along just one cell? the rest of several trillions cells die just for the one to be passed. Does that not resemble a cellular level procreation? (it just might be that we are blinded in our thinking by the by products of consciousness and it seemingly non-evolutionary function, but on DNA level the function is very clear, no external meaning of life is needed...)

    thanx for engaging in this, for me wonder land
     
  17. Jul 2, 2006 #16
    One possible explaination for the evolution of death, at the cellular level, is that this particular trait became favorable when organisms wiped out their own species by gluttoning their niche from over-reproduction. I believe it is generally excepted that the conversion of our atmosphere from carbon dioxide to oxygen was due to the rise of several plant like cells. However when all the carbon dioxide was used up there apparently was a mass death of cells which in turn led to the rise of oxygen consuming organisms, joined with the remaining carbon-dioxide producing ones which created a balance. It has been a year since I took biology, so correct me on any major missconceptions.

    -scott
     
  18. Jul 2, 2006 #17
    Cells don't struggle to survive: they just do what they do, which is replicate. Imperfect replications may confer advantages (useful for some environment) on one of its children, and therefore those children will survive better in that environment.

    The cell doesn't want to do anything: it's the automatic mechanisms of imperfect replication and lack of infinitely available resources that lead to evolution.
     
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