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  1. 23 Feb '13 17:36 / 6 edits
    http://phys.org/news/2013-02-evolution.html

    -three different species of bacteria in this experiment evolved independently in exactly the same environment to diversify genetically and in survival strategy in almost exactly identical ways thus proving that evolution can, at least sometimes, be surprisingly very predictable.
  2. 23 Feb '13 18:05
    Is it like like the green tree python, and the emerald tree boa, they are nearly identical but evolved on different continents
  3. Standard member RJHinds
    The Near Genius
    23 Feb '13 18:46
    Originally posted by humy
    http://phys.org/news/2013-02-evolution.html

    -three different species of bacteria in this experiment evolved independently in exactly the same environment to diversify genetically and in survival strategy in almost exactly identical ways thus proving that evolution can, at least sometimes, be surprisingly very predictable.
    That is not evil-lution. That is just variations, which God has allowed for.

    HalleluYah !!! Praise the Lord! Holy! Holy! Holy!
  4. 23 Feb '13 21:05 / 18 edits
    Originally posted by RJHinds
    That is not evil-lution. That is just variations, which God has allowed for.

    HalleluYah !!! Praise the Lord! Holy! Holy! Holy!
    variation via mutation + selection = evolution.

    "just variations", as you said, cannot possibly explain how new variation could have arisen that was not there before the experiment -new strains and genetic code was observed to evolve that was not there in the original bacteria put into the experiment.

    In the case of this lab experiment, the selection was not done by the experimenters thus this was natural selection in the lab with the resulting observed evolution in the lab -the fact that the environment in this case was unnatural is totally irreverent to the fact that evolution was directly observed here and observed in all three species of bacteria.

    -And there is no evidence that a god "allowed for" (as you said) variation or any of this nor is there the slightest reason to suppose a deity might be involved nor is there the slightest reason to suppose a deity is required nor have you given any reason.
  5. 23 Feb '13 21:11 / 2 edits
    Originally posted by e4chris
    Is it like like the green tree python, and the emerald tree boa, they are nearly identical but evolved on different continents
    arr yes, that's called "parallel evolution"
    ( http://en.wikipedia.org/wiki/Parallel_evolution ) .
    Actually, come to think of it, the known observed examples of parallel evolution in nature is further evidence of evolution can sometimes be very predictable -somehow that never occurred to me before until just now. Pretty obvious now I think about it.
  6. Standard member finnegan
    GENS UNA SUMUS
    23 Feb '13 21:48 / 1 edit
    Originally posted by humy
    arr yes, that's called "parallel evolution"
    ( http://en.wikipedia.org/wiki/Parallel_evolution ) .
    Actually, come to think of it, the known observed examples of parallel evolution in nature is further evidence of evolution can sometimes be very predictable -somehow that never occurred to me before until just now.
    Is there not a general suggestion that, just as each species is adapted to thrive in a particular type of environment, so also each specific type of environment virtually invites the appearance of a creature adapted to make use of this? Generally, life is so prolific that such adaptation is highly likely to occur, though not inevitaable. Obviously, in this case the emerging species will have certain predictable characteristics.
  7. 23 Feb '13 21:52 / 2 edits
    Originally posted by finnegan
    Is there not a general suggestion that, just as each species is adapted to thrive in a particular type of environment, so also each specific type of environment virtually invites the appearance of a creature adapted to make use of this? Generally, life is so prolific that such adaptation is highly likely to occur, though not inevitaable. Obviously, in this case the emerging species will have certain predictable characteristics.
    Is there not a general suggestion that, just as each species is adapted to thrive in a particular type of environment, so also each specific type of environment virtually invites the appearance of a creature adapted to make use of this?

    Yes, I believe so. That makes perfect sense to me.
  8. Standard member RJHinds
    The Near Genius
    23 Feb '13 22:07
    Originally posted by humy
    variation via mutation + selection = evolution.

    "just variations", as you said, cannot possibly explain how new variation could have arisen that was not there before the experiment -new strains and genetic code was observed to evolve that was not there in the original bacteria put into the experiment.

    In the case of this lab experiment, the selection w ...[text shortened]... is there the slightest reason to suppose a deity is required nor have you given any reason.
    The Holy Bible tells me so. That is more than just a slight reason to believe.
  9. Standard member finnegan
    GENS UNA SUMUS
    24 Feb '13 01:02 / 1 edit
    Originally posted by humy
    http://phys.org/news/2013-02-evolution.html

    -three different species of bacteria in this experiment evolved independently in exactly the same environment to diversify genetically and in survival strategy in almost exactly identical ways thus proving that evolution can, at least sometimes, be surprisingly very predictable.
    At the start of the experiment, each population consisted of generalists competing for two different sources of dietary carbon (glucose and acetate), but after 1200 generations they had evolved into two coexisting types each with a specialized physiology adapted to one of the carbon sources.

    Points of interest.

    1,200 generations can be observed in the history of a population of bacteria within a very modest human timeframe but it is an awful lot of generations.

    It is curious that the bacteria find an evolutionary advantage in becoming specialists rather than generalists, given access to both acetate and glucose, and that it is okay to specialise in either the one or the other, rather than either acetate or glucose being inherently preferable. Specialising would seem to me to make each population more vulnerable, generalising to make them more sustainable. On the other hand, I can envisage the notion that some bacteria prefer acetate and some prefer glucose for reasons that are trivial and just reflecting individual differences, which always exist in any population. So I would conclude we cannot just use commmon sense to assume how evolution will work. We do have to check what really happens.

    With bacteria we are not dealing in sexual reproduction so once a difference exists between two groups in the population, there is no reason for it to be averaged out again by random mating. The difference will persist.

    I'd like to know more about what is meant by referring to "mutations."
    Any evolutionary process is some combination of predictable and unpredictable processes with random mutations,...
    If random mutations were critical, then I would understand why there might be some surprise about the similarity of the changes in separate populations. However, if instead the basis for change is individual differences, then there is no process of mutation required and there is less reason to be surprised, if any reason at all. The differences might just become emphasised over generations to the point where there is a real gap between two groups of descendents. As a rule, mutation is far more likely to be harmful than helpful to adaptation and I think it gets too much emphasis. I think ( and lots of what I have read says the same) that most of evolution concerns the impact of individual differences, which are universal - no two creatures share totally identical genes with the exception of identical twins.
  10. Standard member sonhouse
    Fast and Curious
    24 Feb '13 01:56 / 1 edit
    Originally posted by RJHinds
    That is not evil-lution. That is just variations, which God has allowed for.

    HalleluYah !!! Praise the Lord! Holy! Holy! Holy!
    It's really funny, you base all your so-called wisdom on a book made for primitives with zero knowledge of science, like a primer for 1st graders. Yet you go on believing in it even though the level is aimed more like for Dr. Seuss. And you swallow the primitive story hook line and sinker. For instance, it seems pretty clear we can believe Newtonian gravity and most of us agree with Einsteinian gravity. NONE of that was in your bible. Yet you believe everything in there in spite of the fact there has been a thousand years of solid scientific progress. It takes an incredible level of blindness to ignore 1000 years of scientific advancement.
  11. Standard member RJHinds
    The Near Genius
    24 Feb '13 02:18
    Originally posted by sonhouse
    It's really funny, you base all your so-called wisdom on a book made for primitives with zero knowledge of science, like a primer for 1st graders. Yet you go on believing in it even though the level is aimed more like for Dr. Seuss. And you swallow the primitive story hook line and sinker. For instance, it seems pretty clear we can believe Newtonian gravit ...[text shortened]... ress. It takes an incredible level of blindness to ignore 1000 years of scientific advancement.
    Whoever wrote that book made for primitives had more knowledge of science than the evil-lutionists of today.
  12. Standard member sonhouse
    Fast and Curious
    24 Feb '13 03:24
    Originally posted by RJHinds
    Whoever wrote that book made for primitives had more knowledge of science than the evil-lutionists of today.
    Oh pleeeze, they couldn't think their way out of a paper bag. They knew nothing of the world in terms of science. All they had was superstition. Which through an incredible set of circumstances, that's all you have too.
  13. Standard member RJHinds
    The Near Genius
    24 Feb '13 06:14
    Originally posted by sonhouse
    Oh pleeeze, they couldn't think their way out of a paper bag. They knew nothing of the world in terms of science. All they had was superstition. Which through an incredible set of circumstances, that's all you have too.
    I have much more that you realize; and you don't realize it, because you will not dare pull your head out of your arse long enough.
  14. 24 Feb '13 08:38 / 2 edits
    Originally posted by finnegan
    At the start of the experiment, each population consisted of generalists competing for two different sources of dietary carbon (glucose and acetate), but after 1200 generations they had evolved into two coexisting types each with a specialized physiology adapted to one of the carbon sources.

    Points of interest.

    1,200 generations can be o ersal - no two creatures share totally identical genes with the exception of identical twins.
    I agree with much of what you say here.

    As a rule, mutation is far more likely to be harmful than helpful to adaptation and I think it gets too much emphasis.

    the vast majority of mutations are harmful so will not help in adaptation.
    However, it isn't the vast majority of mutations that are harmful that counts here -these ones literally count for nothing simply because they are constantly being weeded out by natural selection.
    It is only the 0.001% (or whatever the actual figure is) of mutations that are beneficial that count because they do help with adaptation.

    Without that 0.001% (or whatever the actual figure is) of new beneficial mutations, yes evolution can continue at least for a while, BUT, eventually, once the adaptation that is required needs to go beyond a certain extreme point that requires a truly new gene or a truly new variation of a gene that just was not there before, evolution would come to a grinding halt. For example, for a plant to adapt to the cold, it would help if it had a new mutation to give it an antifreeze protein that would give it extra protection from freezing. But if that initial population of plants never had such a gene anywhere, then without a mutation to give such a gene, the plant will never evolve to have that antifreeze protein even if having it would be the only way forward.
  15. 24 Feb '13 08:47 / 2 edits
    Originally posted by RJHinds
    I have much more that you realize; and you don't realize it, because you will not dare pull your head out of your arse long enough.
    I have much more that you realize

    Oh the news about what you got just keeps getting worse and worse and worse.