Why is natural selection not random?

Discussion in 'Biology & Genetics' started by darryl, Jun 1, 2012.

  1. darryl Banned Banned

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    Been reading What Darwin Got Wrong by Jerry Fodor and Massimo Piattelli-Palmarini and they both seem to be saying natural selection is random and not directed like most scientists believe it to be.

    Can anyone explain why natural selection is not random?
     
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  3. kx000 Valued Senior Member

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    Yes. It is semi-random because random things happen that can kill man A, or cause a chain of events which lead to the death of man A. Ex. Old man drives his car through your front door squishing A. However, it is not totally random because I am me, I am driving this car. Plus, I can plan the extinction of all man kind.
     
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  5. spidergoat Valued Senior Member

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    Because differential survival and reproduction rates depend to a great degree on the fitness of the individual.
     
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  7. origin Trump is the best argument against a democracy. Valued Senior Member

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    I am not sure what you are trying to say so lets use an example.

    Lets assume the world begins to cool and enters an ice age over time. The animals that survive the cooling will be the ones that are best adapted. There is random variation in every species, the random variation in, say body hair will favor the animals that have the thickess hair during a cooling period. They will reproduce and the trait of warm fur will become the norm.

    This is just a cheesy little example that hopefully will point out how a random variation can lead to an animal adapted for a particular climate.

    Since you are reading a book named "What Darwin Got Wrong", you may not really be interested though.:shrug:
     
  8. kx000 Valued Senior Member

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    If you leave it to the chef he will give you a random dish, if you know the ingredients you can cook what ever you want.
     
  9. rpenner Fully Wired Staff Member

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    Perhaps you need to quote the relevant passage.

    In re: Fodor and Piattelli-Palmarini:
    Douglas J. Futuyma, "Two Critics Without a Clue", Science 328: 5979, pp. 692-69 (7 May 2010)
     
  10. Aqueous Id flat Earth skeptic Valued Senior Member

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    Yes I can.


    Can you define "natural selection" and "random" and "directed"?
     
  11. Kumar Registered Senior Member

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    Can't it be this way?

    Natural Selection: selection based on an inherent sense of right and wrong.
     
  12. Aqueous Id flat Earth skeptic Valued Senior Member

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    No that would be called human selection, or choice.
    Natural selection does not derive from humans, but from nature.
    Which is why it's called "natural".
     
  13. Emil Valued Senior Member

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    If there is random then there is no causal determinism.
     
  14. Aqueous Id flat Earth skeptic Valued Senior Member

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    You have chosen two authors who are not even biologists and whose work is discredited.
    :shrug:
    Evolutionary biologist Jerry Coyne describes this book as "a profoundly misguided critique of natural selection" and "as biologically uninformed as it is strident." while In a review in Science Douglas J. Futuyma concluded:
    Because they are prominent in their own fields, some readers may suppose that they are authorities on evolution who have written a profound and important book. They aren't, and it isn't.​
    Adam Rutherford, editor of Nature writing in The Guardian also reviewed it negatively.​
    Natural selection is what it is. Can you explain what it is? In other words, natural selection is not at dispute here, just a misunderstanding over the value of your authors' work.
     
  15. wellwisher Banned Banned

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    Natural selection is not random because it is based on fitness in the context of environmental conditions. This, more often than not, implies logical choices based on given external parameters. For example, if the weather remained cold, selection would go to those who are fit in the cold not those who are fit in the hot weather. This is semi-predictable. Random would flip a coin with the result of 50/50 extinction. Survival requires more than a coin toss. You don't randomly rub two fish together to make a fire.

    The DNA generates randomness in terms of new genes. This assures that there is enough variety of attributes so there is a better fit for the direction needed by natural selection.

    What is left out of this analysis is the entropic force. In the case of osmosis, random events at the molecular level, based on entropy and the second law, leads to a directed force at the macro-level. Life, by being expressed in the liquid state of water, makes use of this template with the randomness within the DNA, leading to a sense of direction in the macro-state of natural selection.

    There is also reverse osmosis, where we can use negative entropic force to create order out of randomness; salt to pure water. If you needed specific genes on the DNA, theoretically, you can leverage the negative entropic force in a directed way to create order out of genetic randomness.
     
  16. kx000 Valued Senior Member

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    Why not?
     
  17. Aqueous Id flat Earth skeptic Valued Senior Member

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    Fitness and environment are always predictable? The outcome is always predictable?

    Fish are adapted to water. If I set up a tank of water and put a live fish in it, does this mean it will live with 100% certainty? That the randomness goes away?
     
  18. Emil Valued Senior Member

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    Randomness:
    Determinism- a direct consequence of a non-random world
     
  19. darryl Banned Banned

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    So far I have come across atleast 12 different definitions of what natural selection is, different websites/books seem to be saying different things. It would help if you could define it, then we can discuss if it is random or not.
     
  20. Grumpy Curmudgeon of Lucidity Valued Senior Member

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    darryl

    There are different answers because they are answers at different levels of comprehension.

    For example, NS is basically survival to reproduce. This means the traits you have are good enough for you to survive long enough to reproduce your form of life in the environment you find yourself in.

    On the next level of detail it means that in the competition for resources you are able to spread the genes you have into the population of creatures similar enough to you to reproduce.(populations evolve, not individuals).

    On the genetic level it is the increase of allels among the genome.

    Of course, all of these pertain to the "winners" in the competition of life, the losers are no longer around. All of these "select" for better fit to the environment by the simple process of killing those that do not fit.

    We are all an extremely lucky tribe of apes trying to describe reality with a language evolved to tell each other where the ripe fruit is. It is often difficult to do so with any accuracy or understanding.

    Grumpy

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  21. Emil Valued Senior Member

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    Perhaps better understand natural selection, first would need to understand artificial selection.
    http://bioap.wikispaces.com/ch22 collaboration :

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  22. Emil Valued Senior Member

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  23. Kumar Registered Senior Member

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    Inharent sense can be there in all live beings. That may suggest directed selection.
     

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