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Evolution chooses for life to die

  1. Aug 16, 2007 #1
    why doesn't life choose to keep living - is evolution stupid or crazy in that case?

    All life promotes its own kind by reproduction. Life is designed or has chosen to reinforce its existence so that it will continue. It is a mandatory priority for life to continue its existence.

    Why does life not also choose to not die? Life is designed to reproduce and it is designed to die. Why does life decide to not program its cells to manage themselves so that they will reinforce themselves with methods or material that would be maintenance for nonstop survival?

    Life defends itself from damage. Does life psychologically enjoy the physical pain from the process of death, is it suicide because it chooses not to develop into an item that does not die?

    Perhaps death is protection from overpopulation and reproduction is protection from extinction? On the contrary, I don't think life can consciously fathom the potential of overpopulation when a population is not restricted into an immediate small space.

    I assume there is an error within the programming of the design life. There is no physical reason life should choose to not continue living, certainly the means are available.

    I think the error is caused from a cogito dilemma. The cogito has violated a rule that is not physical, only this could cause the error.
     
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  3. Aug 16, 2007 #2

    DaveC426913

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    OK, for starters, let's not anthropomorphise anything - for one, you risk the thread getting shut down. Evolution and organisms do not "choose" anything.


    The driving force for evolution is not for "an organism to live", it is for "an organism to reproduce".

    After reproducing, an organism not only has no effect on evolution, it actually has a negative effect (by eating up resources that could be used by others still reproducing).

    Setting aside the benefits of elder wisdom and group nurturing, evolution would drive organisms to die the moment their reproductive cycle is finished - which is the case in many species of insects and arachnids.
     
    Last edited: Aug 16, 2007
  4. Aug 16, 2007 #3

    jim mcnamara

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    Dave has it exactly - plus, humans and most other mammals need to live long enough after birth to assure the survival of essentially helples young.

    But mammals do reach an age point where reproductive success goes down, and the individual becomes less able to fend for itself. Which is why creaky old mammals are very uncommon in the wild - this is the "using up" resources prevention thing Dave mentioned. Creaky oldies are sitting ducks for predators.
     
  5. Aug 16, 2007 #4

    mgb_phys

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    Since most life on the planet is bacteria and you could argue that an individual bacteria never ages or dies - then most life doesn't die.

    Of course there are a few larger lifeforms which do have this problem but they aren't statistically significant.
     
  6. Aug 16, 2007 #5
    That's it! As soon as humanity learns to reproduce by mitosis, we will be eternal! :rofl:
     
  7. Aug 16, 2007 #6

    mgb_phys

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    I thought that was the normal way for physicists?
     
  8. Aug 16, 2007 #7
    Either life chose for itself or something made the choice for life to die instead of live and for it to prioritize reproduction instead living.

    Evolution (as it is described in theory) is an intelligence, it acknowledges its own environment and responds to it because of its own intention to increase life's existence. This type interaction occurs, and where did the command come from?
     
  9. Aug 16, 2007 #8

    russ_watters

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    No. You misunderstand the theory. When you drop a rock, who chooses whether it goes up or down?

    Gravity is not a choice, neither is evolution. Gravity is a physical force and evolution (or rather, natural selection) is similarly a force on the gene pool that pushes development in a certain direction.

    Consider your eyebrows. You and your cro-magnon buddy are out hunting one day and two wildabeasts appear in front of you. Needless to say, you start sweating. You have thick, bushy eyebrows and your buddy has very thin eyebrows. When the wildabeasts lunge at you and your friend, the sweat running down your forhead gets intercepted by your eyebrows, your vision stays clear, and you successfully kill it with your spear. Your buddy is not so lucky. His eyebrows are too thin to stop the sweat from entering his eys and clouding his vision. He misses his wildabeast and gets eaten.

    Did you decide to live and your buddy decide to die? Of course not. Both of you wanted to live. Nature caused you to live and your buddy to die and therefore selected the trait of thick, bushy eyebrows to be advanced to the next generation. That's evolution caused by natural selection.
     
    Last edited: Aug 16, 2007
  10. Aug 16, 2007 #9
    russ,

    a rock does not try to avoid being crushed

    There has been some incorrect data applied somewhere within the evolution theory. Therefore, the theory is not assembled with veracity correctly into a completed solution.

    I understand your statement pertaining eyebrows evolving
    ...but what is the initiating force that chooses to make improvements?
     
  11. Aug 16, 2007 #10

    Evo

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    I believe this is where you are confused. There is nothing choosing to "make improvements". If a new trait results in a better survival rate, then that characteristic will continue, whereas the less successful trait may vanish.
     
  12. Aug 16, 2007 #11
    Ack! :yuck:

    You need to refrain from words such as "choice", "acknowledge", or "consciously fathom" when thinking about life and evolution.

    Try to think of it on more of a genetic expression level rather than an organism level. A change in "signals" present can alter the way in which a gene is expressed....this is the fullest extent of the "consciousness" you seem to want to attribute to it. In addition to this you have random mutations, transposable elements, duplications, retroviruses, etc. etc. than can alter a genome and when couple these with natural selection (the ultimate judge, jury and executioner) you get evolution.

    ...unless, of course, you are one of those creationist types. :tongue:
     
  13. Aug 16, 2007 #12

    DaveC426913

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    You need to back up and get in the habit of asking questions and resist the urge to draw conclusions. The world, and this board, are only too happy to indulge a questing mind.

    It is critical to understand that evolution is an "emergent process" - a large-scale effect resulting from repeated applications of forces on small scales. Emergent processes are legendary for generating very complex and "intelligent-looking" results despite the fact that there is absolutely no designer or guiding force.


    Rocks do not evolve, but they too can be the subject of emergent processes.

    Take a bucketfull of gravel with rocks of widely varying sizes - from sand grains up to skipping stones.
    Repeatedly, vigorously and continuously shake the bucket.
    After several minutes, you will discover to your delight that all the large rocks will be sitting on top of the smaller ones, including the sand.

    How is this possible? Large rocks are very heavy, small rocks are very light.

    Yes, but the small grains of sand can slip down in the cracks between the large rocks and as they do so, the cumulative effect is that the large rocks end up on top. (Look at it another way: a bucketful of large rocks is less dense than a bucketful of sand - because of all the gaps. The large rocks float!

    This is an example of an emergent process. A disordered array of objects has been, through the repetition of a physical phenomenon, organized into stratified layers. Note that, while you applied the force, you did not GUIDE or CHOOSE the effect. The force could just have easily been applied by thousands of years of pounding surf.

    I am not suggesting that the rocks "evolved" or anything, I am merely pointing out how physical processes - and physical processes alone - can generate very complex results with no intention-aforethought.
     
    Last edited: Aug 16, 2007
  14. Aug 17, 2007 #13

    russ_watters

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    Irrelevant. In the example I gave, the humans didn't choose either (both would have chosen to live if they had been given the choice).
    No. Evolution is not wrong, what you are saying about how it works is wrong. You simply don't understand or refuse to accept how it actually works. And these questions you are asking show that quite clearly:
    If evolution could be summed-up in one sentence, it could be: Evolution is changes in species caused by the natural selection of random variations in traits.

    So evolution has two parts:
    1. Diversity in the gene pool - in reality there are several causes of this, but the first one to understand is genetic mutations. Genes get changed by random mutations.
    2. Natural selection of the better (to live or reproduce) or worse (to die or not reproduce) of these traits.

    You really need to take a step back and accept your ignorance or you will never learn anything. You can't assume a theory is wrong when you don't even understand what it's most basic tenets claim. There is also an element of arrogance to your stance here: Hundreds of thousands of scientists have studied evolution in considerable depth, yet somehow you think you have found a flaw in it with a knowledge level surpassed in the first fifteen seconds of a high school biology lecture on it.
     
    Last edited: Aug 17, 2007
  15. Aug 17, 2007 #14
    I added heritable there, just to make the sentence 100% complete. In other words successfull traits are passed on to the next generation of organisms. Added for venturerite's sake, I know you understand this Russ.
     
  16. Aug 17, 2007 #15
    I dunno folks. Venturite may have a good question, though his reasoning is flawed.

    Let me try to reframe the question in a way that's less objectionable:

    "why does reproduction take precedence over repair at the organism level"

    I think framed this way, the question now falls under what would formerly be called "natural philosophy" as opposed to a open ended criticism of the "mechanics of natural selection".

    On the other hand, we could try to look at it mechanistically:

    "what physical laws are responsible for giving reproduction precedence over repair at the DNA level".

    or, perhaps:

    "Does physical laws preclude a reformulation of DNA structure that would favor repair over reproductions"

    ...and so on.
     
  17. Aug 17, 2007 #16

    DaveC426913

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    But how would "repair" evolve without reproduction to select it?

    "Repair" is a trait that is still passed on through reproduction. Once the organism stops reproducing, a "repair" trait will no longer be selected.

    The point here, is that "organisms living longer" is simply not a trait that is selectively encouraged. (except indirectly, through say, longer fertile phase, or through social behavior).
     
  18. Aug 17, 2007 #17
    Exactly. It's not that "reproduction" would be excluded, just not favored over "repair" say.

    In such a species long life spans would be the norm. But in times of environmental change, where natural stresses exceed the organisms ability to repair (even though favored), reproductive rates would be lower than the mortality rates quickly leading to species extinction.

    That is the best answer as to why we find things the way they are, evolution "selected" DNA that favors reproduction over repair.

    I think that's the answer Venturerite is looking for.
     
  19. Aug 17, 2007 #18

    chroot

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    Evolution already has a concise definition: the change in allele frequency over time.

    If it were possible for a living organism to repair itself perpetually, it's possible that life would not have evolved reproductive cycles. As has been mentioned, many bacteria can essentially repair themselves indefinitely, and are "immortal."

    Multicellular life, on the other hand, is nowhere near as capable of repairing itself. Consider the human cardiovascular system: plaques build up in the arteries, and we lack the capability of automatically repairing this damage. Some of the causes of ateriosclerosis are age-related, as tissues are no longer as resilient as when they were young. Even if the tissue itself did not age, though, the ravages of the environment (eddies in the flow of blood past bifurcations, fat in the diet, etc.) would still lead to the formation of plaques and eventual death.

    So, there was a "decision-point" in the evolution of early multicellular life: it either needed to be able to repair itself indefinitely, or it needed to find strategies of reproducing itself, circumventing the inevitable death of individuals. The evolutionary leap from immortal single-celled organisms to immortal multicellular organisms is an absolutely staggeringly large leap, one that has not yet been made.

    It's possible that large, immortal multicellular organisms will one day evolve, but they will necessarily be far more complex than even human life. If you think about it, modern medicine may soon be able to turn off some of the aging processes at the cellular level -- but we'll have to invent numerous industries for the macroscopic pitfalls of age: cleaning arteries, fixing ragged joints, repairing worn vertebra, and so on.

    - Warren
     
  20. Aug 18, 2007 #19

    russ_watters

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    I was going more for a description than a definition. How it happens.
     
  21. Aug 18, 2007 #20

    DaveC426913

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    Why would they? How does immortality increase their numbers so that the immortality gene becomes dominant in the species? It doesn't.

    Unless their fertile phase grows as well.

    But you don't need to live long to have millions of offspring. Many species do that today easily enough.
     
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