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Milton Fuller

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Why is evolution considered a fact?

A key component of evolution is spontaneous generation. If Pasteur refuted spontaneous generation in the 1800's, why is evolution considered a fact? ,


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  • May 8 2013: This is one of the great misconceptions about evolution. Like all scientific theories, it is subject to revision as we learn more about it. Spontaneous generation was Lamarck's theory which Darwin rejected. However, Darwin continued to search for the mechanism of evolution, which evaded him. He revised The Origin of Species 6 times, and wrote about his frustration at not being able to supply the explanation for his observations. Sadly, he died with Gregor Mendel's groundbreaking genetic work with pea plants unread on his desk. The current theory of evolution does not embrace spontaneous generation.
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      May 9 2013: Theory meaning it's not a fact.
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        May 9 2013: First of all. I feel like you are trying to start a debate here. This is a place for questions, and if you aren't going to acknowledge what the fine gentlemen are saying above me, then you might as well not ask at all. Your attitude seems like you're challenging us to prove that evolution is a "fact." I know, it's hard to be criticized by a teenager, but it had to be done.

        Moving on to the statement.

        There are two ways the word "evolution" is used that are not identical, and they equivocate between them.

        The first way is the phenomena called evolution. This is the fact that the lifeforms observed in the fossil record change over time, and, in general, exhibit increasing complexity. EVOLUTION IS A FACT. IT IS A NATURAL PHENOMENON.

        The second way is the the theory of evolution through natural selection. This is an attempt to explain the phenomena of evolution by arguing that it is the result of differential survival based on heritable, individual traits. NATURAL SELECTION IS A THEORY.

        Now, you can argue against the theory till you are blue in the face, it doesn't make the phenomena go away. You can argue that the phenomena doesn't exist, which is much harder to do. In doing this, you would miss that the phenomena is not the theory.
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          May 9 2013: Hi Michael,
          ""This is the fact that the lifeforms observed in the fossil record change over time, and, in general, exhibit increasing complexity. EVOLUTION IS A FACT.""

          Lifeforms in the fossil 'record' do not change over time, they stay exactly as they are. People make the assumption that one transforms to another via absent intermediaries. This is pure conjecture. Many qualified scientists have no time for this hypothesis, let alone accept it as fact.

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          May 10 2013: BRAVO!
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          May 10 2013: Michael I applaud you for your interest in the topic at such a young age and I do not consider your comments as criticism because you can learn from anybody. However, am I to accept only the responses that are pro-evolution but ignore Peter's responses which might be more convincing? I simply asked a question and will consider all responses. Thank you for taking the time to respond to my question.
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        May 11 2013: Somehow can't reply to my own post. Well here goes.

        Peter's response: Lifeforms in the fossil 'record' do not change over time, they stay exactly as they are. People make the assumption that one transforms to another via absent intermediaries. This is pure conjecture. Many qualified scientists have no time for this hypothesis, let alone accept it as fact.

        First of all, I don't think Peter fully understood the post he responded to. The conjecture that one transforms to another via intermediaries is explained by natural selection, which is indeed a theory. Just the fact that they changed is called evolution. That was the original premise of my above post.
        Secondly, the Hardy Weinberg states that genetic and phenotypic frequencies will remain the same absent variables. Conversely, because phenotypic frequencies changed, there has to be some sort of explanation; natural selection attempts to explain it.
        Thirdly, the fossil record is not the only evidence. There's plenty of biochemical observations as well.
        Finally, can you please state which qualified scientists (i.e. accepted in the peer review community) have "no time for this hypothesis?"

        I encourage you to read some books and research. I understand that you have Christian faiths, in which case I have no interest in trying to get you to believe what I believe in. My hope is that eventually, faith and science will no longer conflict, but rather coexist.
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          May 12 2013: Hi Michael.
          There are others.

          To be clear. Natural selection is widely accepted as a mechanism for refining creatures to suit their environment. This is change & many call it evolution. However, evolution is also credited with a simple to complex ability where creatures can change into different, improved, creatures. I believe it is this aspect of evolution which is the subject of the question.

          Abiogenesis is widely held to be separate from evolution; however if you reverse engineer evolution to it's roots, then we must have an inanimate object becoming alive by natural means. Difficult to understand how we can separate them.
        • May 12 2013: Peter,

          We can separate them because the mechanisms for life to originate are not the same as those involved in the evolutionary process. The god you worship might be, for you, an all-or-nothing issue. But reality is not. Knowledge is not. I would not start rejecting all the clear knowledge we have about how gravitation shapes the orbits of the planets just because I have no idea about how the universe started, or because I don't know if the universe started. I would not deny the knowledge I have about mycobacterium leprae being behind leprosy just because I don't know where this bacterium comes from. I would not renounce any well-established knowledge because there's so much I don't know. The same is true about evolution. There's so much evidence that denying it because we don't know how life started would be silly.

          In natural terms, you are right, they are not separate. There has to be life first before there's evolution. But, for example, if we have enough evidence to establish that we share common ancestry with a lot of other life forms, then there's no denying it just because we can't establish other common ancestries with the same confidence, or just because we don't know how life started.

          One more: If I know that I have a stomach hernia, not knowing how my stomach developed won't change the evidence for both my stomach and the hernia. Right?

          Why is this so hard for you to understand? Pay attention: I am not asking you to accept evolution, I am not asking you to accept abiogenesis, but to understand why these two are separate in scientific terms. Why is this so hard to understand for you?
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          May 13 2013: Hi Entropy.
          Most articles on evolution start with the Big Bang & end with Homo Sapiens. I guess we can allow for poetic licence, but are we giving the wrong impression to youngsters & others, learning this for the first time?
          My personal view is that all creatures were created perfect & as they breed, & diversify, they accumulate mutations which make them weaker. So we have a degeneration over the years.
          I assume your view would be the reverse. Things started off in a simple manner,& are improved by natural selection, so that creatures get more complex. I accept natural selection btw; just don't accept that it's benefits can overcome the degeneration.
          So really we need a start point for evolution, which would, I guess, be the point at which natural selection can have an effect, but this is never made clear. So I see your position as one where a pretty startling happening converted dead atoms into a form of life that could be operated on by mutation & natural selection. Then & only then, does evolution start. Am I on the right track? Do you believe this?
          Ignoring the abiogenesis bit, it would be of interest if you could point to some evidence that we are evolving into better beings, or some other evidence that evolution is actually improving things. Something concrete that would enhance the 'Fact' status. Fruit Flies are still Fruit Flies.

        • May 13 2013: Hello Peter,

          It dos not matter if most "popular" articles on evolution start with the big bang or not. The important thing is whether you understand why abiogenesis and biological evolution can be treated separately as I explained before. It should not take too much effort on the part of youngsters and others learning about this for the first time to understand the differences no matter how a quick popular presentation looked like. Nobody would talk about the processes and evidence for biological evolution as if they were the same as those for the big bang or for abiogenesis.

          Your question about degeneration/improvement seems also misinformed. The meaning of improvement depends on the environment. Evolution then would improve organisms for such circumstances, but not necessarily for other circumstances. If a population is all right in its environment, then there will be no further improvements. Evolution does not stop though, because random fluctuations in gene versions (alleles), might change appearances and such with no improvements involved. Evolution is not about improvements, but about survival. Yes, life started simple, and more complex life forms have appeared. But complexity and improvement are not synonyms, and, again, improvement is relative to the environment.

          "Degeneration" can only happen where too many genetic defects can be passed on to offspring. If not, then there's no reason for degeneration. This has been shown mathematically numerous times. It's all about the probability of mixing deleterious mutations at reproduction.

          But your degeneration question is not what needs answering to get to the fact status. We could talk about that later on.

          I do not understand your fruit flies comment. Do you think that flies adapted to new environments are not better flies for those environments than the original populations?
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          May 14 2013: Hi Entropy.
          The Fruit Fly comment refers to the efforts to 'evolve' Fruit Flies. They have a very rapid turn-around, so this makes them ideal for mutation/selection experiments, but so far we just get damaged Fruit Flies.

          ""Despite decades of sustained selection in relatively small, sexually reproducing laboratory populations, selection did not lead to the fixation of newly arising unconditionally advantageous alleles.""

        • May 14 2013: Hi Peter,

          Apparently you linked to a creationist web site. I see mention of ID, and some misquoting spiced with a few misconceptions about population genetics (the author does not seem to understand the words used, and instead gives them a more colloquial meaning).

          Anyway, I said that "improvement" depends on the environment. It is as illogical to expect an advantageous mutation will be advantageous in every environment, as it would be to expect that an eagle's wing will be advantageous at the bottom of the ocean. Therefore, why would you find a problem for evolution if mutations are conditionally advantageous rather than unconditionally advantageous?

          I see no reason why fruit flies that develop faster would be called "damaged" flies by the way.

          If you are searching the creationist literature for evidence that evolution works, I am not very surprised that you have not found it. The day those guys start presenting data and evidence with honesty I will start thinking that our planet might be six thousand years old and the moon is made of cheese.

          So, any questions about our conversation? Do you understand now why we can separate abiogenesis and biological evolution? Do you understand that degeneration and improvement depend on the environment and that evolution is not just improvement, but depends on environment, and that degeneration depends on probability for deleterious alleles (bad genes) to survive by being passed on in reproduction?
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          May 15 2013: Hi Entropy.
          The fruit fly experiments are being run by evolutionists. I guess they are well aware of the best ways to make evolution happen. If they succeed then I'll need to back off, but as yet no sign.

          The way I see it is that improvements can occur in any given creature, dependant on the environment. This can be demonstrated, this is science. We call it micro-evolution. From that point you are assuming abiogenesis, and macro-evolution. Neither of these can be demonstrated, they are not science. When / if they are demonstrated then we can discuss how they came about. Until then all we have is two different opinions; not a fact & a fairy story.
          Cool name btw. That's the main reason that abiogenesis is probably a non-starter.
        • May 15 2013: Hi Peter,

          If the scientific work is presented by a creationist they will always quote in a misleading way. That's a given. Example, it's obvious to me that there's nothing wrong with flies having advantageous mutations but not unconditionally advantageous mutations. That's normal. But the creationist site had to insist on that as if that meant failure, which it isn't. Did you understand that there's nothing wrong about flies having mutations that are conditionally advantageous? If you expect unconditionally advantageous mutations you don't understand evolution. No wonder you would not accept it.

          From microevolution (evolution within the species) we get to see that improvements do happen, and that proposed mechanisms can do quite a lot of stuff, like making a fly develop faster. But we don't suggest that such thing proves abiogenesis. I don't know what makes you think that. We don't get macroevolution from that alone either. There's much more to macroevolution and its evidence than those experiments. Way much more. Both abiogenesis and macroevolution are science. I truly don't see why they would not be. Maybe you mistake science with final judgement. For macroevolution, there's enough evidence that we know it's a fact, but final judgement about how much different processes contribute to it is far from decided. For abiogenesis there's research, yes, scientific research, but it's not final judgement. We don't know how it happened. We just know there's no reason why it would not happen.

          Now, you might not like that I talk about abiogenesis as a given, but that would be a different discussion. Just remember that we don't use microevolution to "prove" abiogenesis. Experiments on microevolution do help macroevolution, but it is not the single thing that has convinced us that macroevolution is real. There's much much more.

          That's it for now.
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      May 9 2013: I think there is a confusion here. Evolution is a fact because it's effects are observable and verifiable and repeatable. Evolution in itself is not a theory.
      That evolution takes place with sufficient trials under the conditions of environment such that only the fit trails triumph and survive whereas the unfit trials get weeded out and that the whole process is 'dumb' without any supernatural intervention is a theory of evolution proposed by Darwin. It is not a fact per se, it is a theory - highly successful one.
      The Cosmological Evolution is another fact. The standard Hot Big bang model the most favored theory of this evolution.
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        May 9 2013: Hi Pabitra.
        It is true that natural selection favours the most fit. However the controversy arises when it comes to the ability of this mechanism to produce a new, improved creature. This is what is postulated from the Darwinian model, but where is the evidence?
        In addition the question relates to abiogenesis, which is a pre-requisite for evolution. The usual cop-out about it not being part of evolution is just that.


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