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Science Forum

  1. 01 May '14 07:32 / 1 edit
    I had heard previous explanations to this phenomenon that has been both observed in the fossil record and in real life. The main explanation, which is slightly simplistic I think but certainly perfectly passable, is that a relatively sudden change in the environment triggers relatively sudden evolutionary change for life to adapt to it and then, once all the new niches have been filled with species evolved to be fully adapted to each one, evolution slows down to its usual slow rate again. This makes perfect sense if you think about it very carefully!

    Although this link below doesn't mention 'punctuated equilibrium', it obviously is a good study that helps to clarify why it happens and I personally find it quite interesting:



    http://phys.org/news/2014-04-competition-ecological-niches-limits-formation.html

    "...The rate at which new species evolve is limited by competition for ecological niches, report scientists from the University of Chicago in Nature on April 30. The study, which analyzes the evolutionary and genetic relationships between all 461 songbird species that live in the Himalayan mountains, suggests that as ecological niches within an environment are filled, the formation of new species slows or even stops.

    "Despite the great diversity of environments and ability for species to move between areas, evolution in eastern Himalayas appears to have slowed to a basic halt," Price said. "Other species have formed elsewhere, such as in China and Siberia, but most have been unable to spread into this region."

    The researchers attribute this slowing of evolution to the filling of ecological niches, or exploitable habitats or resources for new species to adapt to. The formation of new species is usually thought to involve three steps. First, a species expands across an environmental range. Then a barrier, such as climate change or a geographic event, causes the species to separate into distinct populations. Lastly, the development of reproductive isolation—the inability to interbreed—finalizes the speciation process. This cycle then repeats, creating the breadth of diversity seen in nature.

    Price and his colleagues argue that the expansion of a range cannot occur if there are no ecological niches for a species to expand into. Despite the ability of birds to fly and cross geographic barriers, they cannot persist in regions where they are outcompeted by existing species who occupy available niches. In the eastern Himalayas, the researchers found evidence of this in numerous differences in feeding method and body size that appeared early in the evolutionary history of songbirds. Less dramatic ecological differences, such as living at differing elevations, appeared to form later as the initial adaptive radiation slowed.

    "Our argument is that niche filling has stopped species from getting big ranges," Price said. "In the eastern Himalayas, it has become harder and harder for new species to get into that system, and we are quite close to the maximum number of species that can be accommodated. There is little room for more species because niches are increasingly occupied."

    This model for diversification stands in stark contrast to previous hypotheses, many of which have focused on the slow development of reproductive isolation as the limiting factor.

    ..."
  2. 01 May '14 09:59
    Evolution is constantly ongoing in that small changes inevitably occur. Once enough
    changes have accumulated and through freak chance or natural pressure different genes
    are activated, the changes can be dramatic. What this article demonstrates to me is that in
    a stable environment few changes of more dramatic nature will propagate, since it will not
    fit in with the overall environmental structure (and because outside influence can't
    penetrate the environment, it's stable), therefore being outselected through mainy sexual
    selection. Reproduction often suffers when changes in one or a few specimens are too big,
    and the environment can still benefit the ordinary form.

    This is pure speculation on my part, but I believe that's the reason evolution seemingly
    grinds to a halt in an environment such as this. Someone with more insight, feel free to
    correct me or ammend to my statement here.
  3. Standard member RJHinds
    The Near Genius
    01 May '14 12:23
    What real science reveals is that the ability to adapt is programmed in to the organisms by "GUESS WHO"?
  4. Standard member sonhouse
    Fast and Curious
    01 May '14 12:26
    Originally posted by RJHinds
    What real science reveals is that the ability to adapt is programmed in to the organisms by "GUESS WHO"?
    I don't know, tell us, oh maven of science, who is the 'Guess Who'?

    I'm sure there will be a Nobel Prize in that answer.
  5. Standard member RJHinds
    The Near Genius
    01 May '14 12:53
    Originally posted by sonhouse
    I don't know, tell us, oh maven of science, who is the 'Guess Who'?

    I'm sure there will be a Nobel Prize in that answer.
    Just stop to think about WHO would it have to be to have intelligence greater than any one you know that exists today or ever that might be able to do such a thing. Do you know enough to calculate the odds of it happening by accident?
  6. 01 May '14 13:02 / 2 edits
    Originally posted by sonhouse
    I don't know, tell us, oh maven of science, who is the 'Guess Who'?

    I'm sure there will be a Nobel Prize in that answer.
    I had a quick peek at what you were responding to and I note his exact words were; “...the ability to adapt is programmed in to the organisms...” which, if he is talking about genetic adaptation, is false! There is no “program” that is 'inside' the organism that specifically allows and is for genetic adaptation for what allows genetic adaptation is nothing more than mutation + natural selection neither of which are “programs”. But, as usual, he just too stupid to comprehend even this low level of subtlety.
  7. Standard member RJHinds
    The Near Genius
    01 May '14 13:13
    Originally posted by humy
    I had a quick peek at what you were responding to and I note his exact words were; “...the ability to adapt is programmed in to the organisms...” which, if he is talking about genetic adaptation, is false! There is no “program” that is 'inside' the organism that specifically allows and is for genetic adaptation for what allows genetic adaptation is nothing mor ...[text shortened]... are “programs”. But, as usual, he just too stupid to comprehend even this low level of subtlety.
    Contrary!
  8. Standard member sonhouse
    Fast and Curious
    01 May '14 14:14
    Originally posted by RJHinds
    Contrary!
    That's your big comeback? CONTRARY? give me a break. All you have is contrary. Contrary to what has been learned by scientists of all disciplines in the last 400 years.
  9. Standard member RJHinds
    The Near Genius
    01 May '14 21:24
    Originally posted by sonhouse
    That's your big comeback? CONTRARY? give me a break. All you have is contrary. Contrary to what has been learned by scientists of all disciplines in the last 400 years.
    Well, we now know that there is programming in the DNA within cells. So why should we not think there is programming that controls how much adaptation can take place within the cell? It all stands to reason.
  10. 03 May '14 07:40
    Originally posted by RJHinds
    Well, we now know that there is programming in the DNA within cells.
    Wrong - if by programming you mean the organised, written-for-a-purpose kind typically found in your computer.
  11. Standard member RJHinds
    The Near Genius
    03 May '14 08:38 / 1 edit
    Originally posted by C Hess
    Wrong - if by programming you mean the organised, written-for-a-purpose kind typically found in your computer.
    Yeah, that is what I mean. Here is what Bill Gates of Microsoft said:

    “DNA is like a computer program but far, far more advanced than any software ever created.”

    - Bill Gates, The Road Ahead

    http://www.goodreads.com/quotes/336336-dna-is-like-a-computer-program-but-far-far-more
  12. 03 May '14 09:31
    Originally posted by RJHinds
    Yeah, that is what I mean. Here is what Bill Gates of Microsoft said:

    “DNA is like a computer program but far, far more advanced than any software ever created.”

    - Bill Gates, The Road Ahead

    http://www.goodreads.com/quotes/336336-dna-is-like-a-computer-program-but-far-far-more
    I've already explained how that figure of speech is poorly chosen in other posts. You've
    failed to counter my arguments. Please don't reuse already failed arguments.
  13. 03 May '14 16:37 / 4 edits
    Originally posted by C Hess
    I've already explained how that figure of speech is poorly chosen in other posts. You've
    failed to counter my arguments. Please don't reuse already failed arguments.
    I think I should also point out that Bill Gates isn't a scientists nor an evolutionary biologist nor a geneticist so his exact words on this scientific matter carries no weight at all within the scientific community anyway.
    He is a programmer but, since he is not a geneticist or an expert on DNA, that gives him absolutely no scientific authority on genetics! -wrong field of science -computer programming is NOT genetics!
  14. Standard member DeepThought
    Losing the Thread
    03 May '14 17:34
    Originally posted by humy
    I think I should also point out that Bill Gates isn't a scientists nor an evolutionary biologist nor a geneticist so his exact words on this scientific matter carries no weight at all within the scientific community anyway.
    He is a programmer but, since he is not a geneticist or an expert on DNA, that gives him absolutely no scientific authority on genetics! -wrong field of science -computer programming is NOT genetics!
    Prove that the genetic code does not work in the same way as an event driven program.

    RJ's fallacy is to insist that the presence of a programmer is necessary for the existence of a program.

    I think Bill Gates was thinking more about sales than science when he said that stuff.
  15. 03 May '14 18:34 / 4 edits
    Originally posted by DeepThought
    Prove that the genetic code does not work in the same way as an event driven program.

    RJ's fallacy is to insist that the presence of a programmer is necessary for the existence of a program.

    I think Bill Gates was thinking more about sales than science when he said that stuff.
    Prove that the genetic code does not work in the same way as an event driven program.

    No, that is not what was said in his post. He said “DNA” but not “DNA code”; reminder: “DNA is like a computer program ...” -not “DNA code” but just “DNA”. I would guess that DNA would be more closely analogous to the material components that make up the computer memory that stores the software while the DNA code is more analogous to the computer code but I would urge great caution with such analogies which can be highly misleading. But I suppose it might be a reasonable analogy to think of a genetic code as being like a program so long as one understands this is not pure software we are talking about because the genetic code is made of the ordering of DNA bases which, unlike computer software, does not consist of just pure abstract information but has a material physical existence.