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Thread: What Darwin didn't know.

  1. #41
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    hmm.. but what about genetic algorithms now i have little to no understanding of them
    but from what i could tell (I had thought of doing an extra project on it but then shifted to hueristics) they do utilise the same type of merging of code via data structures and all as is done by the DNA in mutating.
    anything that doesn\'t kill you or your dreams only makes you stronger

  2. #42
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    Like Alleycat said great job with the no flames yet this thread. Now I have noticed in the last few posts that it seems people are interposing evolution and natural selection. Keep in mind these are two different concepts intirely. Natural selection is the idea that the enviromental conditions cause certain 'weaker' elements of a species to die off, or not propogate. Evolution is the organisms moleculare change due to the enviromental stimuli over time.
    \"He who shall introduce into public affairs the principles of primitive Christianity will change the face of the world.\"
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  3. #43
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    I'm not sure you can separate Natural Selection and Evolution so readily....

    If natural selection "weeds out" the weakest of a species they are not, logically, identical to the rest of the species. Say, for example, redheads were being "weeded out" because the predator can see them more easily. They are redheads because, even though they are the same species, their DNA differs from the blond and dark haired people. In a way they are already a "sub-species". Should the environment remain the same, (the predators remain), then, eventually, the redhead's genetic material would be removed from the species DNA - thus the extinction of the "sub-species". The DNA of the species as a whole has changed - no redheads - thus the species has evolved. But it was achieved by natural selection.

    Evolution produced the "error" in the code that threw redheads. Natural selection threw out the redheads because the "code" was not a successful branch. The code has been re-altered. It would be quite possible that, at some time in the future, the "code" errors again and begins throwing redheads and, if the predators have gone, (because they can't catch enough food now the redheads have gone), that the redheads could succeed.

    Or am I completely nuts?

    Oh Hush...
    Don\'t SYN us.... We\'ll SYN you.....
    \"A nation that draws too broad a difference between its scholars and its warriors will have its thinking done by cowards, and its fighting done by fools.\" - Thucydides

  4. #44
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    The redhead analogy sounds rather accurate. I guess natural selection then would be a means by which evolution works.

    Humans evolve a green haired gene. By natural selection the greenheads survive better than the rest since the predators don't eat thier greens, looks like thumper isn't alone on this, instead prefering the flower that is redheads thereby the human race evolves towards a green haired people.

    or is this just the lack of sleep talking.
    \"He who shall introduce into public affairs the principles of primitive Christianity will change the face of the world.\"
    Benjamin Franklin

  5. #45
    AO Ancient: Team Leader
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    That's pretty much the way I see it working.... by chance... If you evolve one way, (there's no conciousness to the change in the code), you might be evolving towards extinction. This is why I believe there to be millions of bits of broken code littering evolution.
    Don\'t SYN us.... We\'ll SYN you.....
    \"A nation that draws too broad a difference between its scholars and its warriors will have its thinking done by cowards, and its fighting done by fools.\" - Thucydides

  6. #46
    AO Curmudgeon rcgreen's Avatar
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    Should the environment remain the same, (the predators remain), then, eventually, the redhead's genetic material would be removed from the species DNA - thus the extinction of the "sub-species".
    This would only remove a characteristic from the gene pool of that species.
    The tough part is assuming that mutation could add a new characteristic.
    That's why I remain a skeptic. Beyond that is another, larger hurdle. Different
    species have different numbers of chromosomes and cannot interbreed.
    How would an altogether new species evolve gradually from an existing one?

    A spontaneous mutation that changed the number of chromosomes in one
    individual would render him unable to reproduce (because he is genetically
    incompatible with everyone else). So, this mutation would have to happen
    simultaneously in at least two individuals, one male and one female. It would
    need to, by coincidence, be the same exact mutation, so that these two
    individuals could mate. Needless to say, they would have to live near each other
    and just happen (by sheer luck) to meet, mate and reproduce. Then, natural selection
    would determine if the mutation was conducive to survival.

    Wishful thinking. People want evolution to be true because they hate God,
    and fear that he would punish them for their sins. Better to pretend the
    bogeyman isn't there, and invent a way that life and intelligence could
    emerge from nothing plus time and a little luck.
    I came in to the world with nothing. I still have most of it.

  7. #47
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    keep in mind the human race has been dealing with mutations that leave us with an extra chromosome for a long time now, people with Down syndrome have an extra chromosome. Im not sure and will google after this post to find the answer, but im pretty sure that someone with Down syndrome can reproduce with someone that doesn't have it.


    Edit: ok i can't find anything on reproduction between a normal human and a down sundrome human due to my lack of free time here at work. But i did find that it is possible for animals with different chromosome numbers to reproduce.

    Horse (64 chromosomes) + Donkey (62 Chromosomes) = Mule (63 chromosomes)

    Now keep in mind that the horse has 64 chromosomes but only 32 pair, and the donkey has 31 pair. The mule, however, has 31.5 pairs due to the extra chromosome. This extra chromosome is the 'odd man out' during reproduction. Since it has no pair, during meiosis , I or II i can't remember, the dividing cell can't pair up the extra and therefore dies, and is the reason mules are sterile.

    SO

    We can infer from this that yes it is possible for animals with different chromosome numbers to reproduce, but thier offspring are more often than not sterile, there have been a few documented cases of a mule bieng able to reproduce, and therefore will be one of the first genetic traits to be eliminated fromt he evolutionary line via natural selection.
    \"He who shall introduce into public affairs the principles of primitive Christianity will change the face of the world.\"
    Benjamin Franklin

  8. #48
    AO Curmudgeon rcgreen's Avatar
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    Trisomy 21 is when the cells have 22 normal pairs of chromosomes but 3 chromosomes of the number 21.
    http://www.medic8.com/healthguide/ar.../downssyn.html

    They have the same number of chromosome pairs, but one pair is anomalous,
    being a "triple". Different species have different numbers of pairs.
    I came in to the world with nothing. I still have most of it.

  9. #49
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    Different species have different numbers of pairs.
    Just like the horse and donkey?
    \"He who shall introduce into public affairs the principles of primitive Christianity will change the face of the world.\"
    Benjamin Franklin

  10. #50
    AO Curmudgeon rcgreen's Avatar
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    Just like the horse and donkey?
    Exactly. When they mate, one horse chromosome remains
    unpaired, so the mule is sterile.
    I came in to the world with nothing. I still have most of it.

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