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    (Original post by evaki)
    But isn't it strange that millions of years would evolve some organ that was so well adapted to whatever that animal needed it for millions of years later? And what on earth would be the purpose of that organ through those millions of years before it could be used ?
    One of the most quoted examples is the eye. The point is each step gives a very slight benefit from the step before. Natural selection has no foresight, it acts for any slight advantage now. That's why lots of living systems look slightly "Heath Robinson" because there hasn't been enough evolutionary pressure to get rid of all of the bits in between etc.

    Ok, the eye. First some "simple" organisms evolved simple light sensitive spots. If they could tell light from dark they could, for example, find sunlight more easily giving them an evolutionary advantage over oganisms without this adaptation. Some animals then developed these type of light sensitive spots into clusters. These gave a greater field of light sensitivity. Then these spots evolved into a slight dip in the organism. This allowed for the organism to roughly work out direction of light. Then the pit got deeper, giving better and better directional detection, until it formed a full pinhole camera and an image could be formed. A thin membrane then developed across the pinhole, focusing the light. Eventually we get to the complex mamalian eye via more and more very small steps, each giving a slight advantage over the previous stage and thus allowing organisms with this adaptation to pass their genes on to more offspring and so on.

    This is what evolution by natural selection is. Once you really think about it, it's common sense, things which are good at replicating get more common, those which aren't go extinct. Are you just playing devil's advocate or do you actually have a valid argument? I'm all ears. Well, that wouldn't give me much of an evolutionary advantage as 2 is plenty, but idioms are idioms.

    phil.
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    (Original post by evaki)
    But isn't it strange that millions of years would evolve some organ that was so well adapted to whatever that animal needed it for millions of years later? And what on earth would be the purpose of that organ through those millions of years before it could be used ?
    I can't think of any organ that started off as useless, but if you know one...I guess the eye could be used as an example: the first 'eyes' were the photosensitive spots of some bacteria, which allowed them to move towards light. As life became more complex, the patches became bigger and the shape changed to produce a sharper image. Then, some animals developed the pupil, and then some developed a lens. At no point during the evolution of the eye was it useless.
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    (Original post by InVinoVeritas)
    That my dear, is science. Every scientific theory starts off as an idea. This is then backed up by evidence, hopefully both observational and mathematical. It is then fine tuned through new discoveries and ideas. Life sciences happen to be a lot less mathematical and a lot more observational in their evidence and so it takes a lot longer to be able to find an overwhelming amount of evidence in favour of say evolution as opposed to say quantum field theory. All scientists agree on both the existance of evolution and its method i.e. natural selection. The only thing up for debate is the fine tuning of the theory, the details of which are often blown out of all proportion and made to look like completely different theories.

    I would bet everything I have that evolution via natural selection is the story of life from ambiogenesis to now. However (assuming I hadn't made this bet :p:) I would gladly accept evolution was wrong in a second if a rival theory which more convincingly explained the evidence we had or if a piece of evidence which flew in the face of evolution via natural selection was found. This, again, is the entire basis of science and it should be applauded. At the end of the day everything we can observe or interpret is limited to the capabilities of the human brain and so on a philosophical level nothing can every be proved, however at this moment in time the only theory which comes at least close to explaining the complexity of life is natural selection. Can we please pick on another scientific theory soon? I'm getting tired of justifying evolution when it is really as fair game as many other theories which people just take for granted.

    phil.
    Exactly, it is science! So why do people believe everything so willingly? Almost religiously?

    People used to believe that the earth was flat, because they had never traveled around it. We could be in a similar position right now. Not meaning that what we have seen so far is wrong, (what they saw was pretty much the flat surface, so.. that part was right, they just had to add the rest of the earth that they didn't see,) but simply that there might be a lot more to discover that might give us a completely different view of how it's all connected.

    Don't feel like you need to justify evolution to me, I believe in some parts of it, and I am skeptical/curious about others. My main reason for questioning some things here is simply that to me it seems like people think a bit like this

    "HEY a theory that we can believe in without needing to believe in God, it MUST be true! I'm in! And I won't ask any questions, cause it's not as crazy as religion anyway so whatever " Not saying you think like that, just that it seems a lot of people do, and we should be careful with that. In respect of science we should be critical to the theories put before us.
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    (Original post by flyingstereowombat)
    I can't think of any organ that started off as useless, but if you know one...I guess the eye could be used as an example: the first 'eyes' were the photosensitive spots of some bacteria, which allowed them to move towards light. As life became more complex, the patches became bigger and the shape changed to produce a sharper image. Then, some animals developed the pupil, and then some developed a lens. At no point during the evolution of the eye was it useless.
    how about lungs as someone pointed out?
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    I evolved from a T-Rex and if you try and tell me any different I'll eat your ******* jeep.
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    (Original post by evaki)
    how about lungs as someone pointed out?
    I'm sure you could find many examples in books if you wanted to.
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    (Original post by evaki)
    I agree with all that and I am aware of all that. And people used to believe that the earth was flat, because they had never traveled around it. We could be in a similar position right now. Not meaning that what we have seen so far is wrong, (what they saw was pretty much the flat surface, so.. that part was right, they just had to add the rest of the earth that they didn't see,) but simply that there might be a lot more to discover that might give us a completely different view of how it's all connected.

    Don't feel like you need to justify evolution to me, I believe in some parts of it, and I am skeptical/curious about others. My main reason for questioning some things here is simply that to me it seems like people think a bit like this

    "HEY a theory that we can believe in without needing to believe in God, it MUST be true! I'm in! And I won't ask any questions, cause it's not as crazy as religion anyway so whatever " Not saying you think like that, just that it seems a lot of people do, and we should be careful with that. In respect of science we should be critical to the theories put before us.
    Just read that post. Fair play to you then, I'm all for being critical of everything . Yes, we could be wrong, but until the argument for evolution via natural selection has been falsified it is the theory which by far and away offers the best solution to the problem. Newton's law of gravity is wrong. It was used for hundreds of years and is still used today. That is because it is a very useful approximation taken from observation. Nothing is certain, we will never know everything and it good to be critical. However some theories just fit the evidence better than others and evolution via natural selection is one of the best fits you can get. I may be sounding a bit moody but that's because I think evolution via natural selection is unfairly viewed as "just a theory" whereas theories in other areas of science, especially physics, are accepted to the absolute truth. They are all "just" theories, but there are different degrees of how likely a theory is to being true.

    phil.
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    (Original post by Charzhino)
    Well for example fish going onto land, and just developing a tracheal lung system to breathe, all by some random mutations. Of course mutations do give rise to new features which are beneficial, but a whole organ?
    It's like saying if the world was flooded, what chances are there of humans developing gills so they can breathe under water and survive.
    You fundamentally fail to grasp the concept of evolution.

    Also see:
    http://en.wikipedia.org/wiki/Lungfish
    http://en.wikipedia.org/wiki/Mudskipper

    Fish that breath from surface air (modern day fish use labyrinth organs) benefit.
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    (Original post by Botticello)
    Whereas some stupid book is more reliable than physical fossil evidence and research.
    what's up with defending evolution by saying that something else is worse?
    If I'm sick I'm still sick even if someone is sicker, if I have a small stone it's still small even though someone else has a smaller stone.
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    Actually, many transitional fossils do exist - for example, there are fossils of transitional organisms between modern birds and their dinosaur ancestors, as well as whales and their land mammal ancestors. There are many transitional forms that have not been preserved, but that is simply because some organisms do not fossilize well or exist in conditions that do not allow for the process of fossilization. Science predicts that there will be gaps in the record for many evolutionary changes. This does not disprove the theory.
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    (Original post by Botticello)
    Whereas some stupid book is more reliable than physical fossil evidence and research.
    The very fact that you attack Christianity by calling the Bible "some stupid book" shows the limit of your understanding. Does the fact that many prominent geologists and biologists reject the theory of evolution and support creationism mean anything to you? Don't just say you haven't heard of any because of the way the media distorts our views on things by taking sides and not publishing things, its all on the web if you googled it.
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    (Original post by nolongerhearthemusic)
    I'm sure you could find many examples in books if you wanted to.
    ok, have you read about it before? How can you be so sure I can find many examples in books if I wanted to?
    It could very well be that I can, but are you assuming that just because you believe the scientists to be correct, or because you've actually seen it yourself?
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    (Original post by cowsgoquack)
    You fundamentally fail to grasp the concept of evolution.

    Also see:
    http://en.wikipedia.org/wiki/Lungfish
    http://en.wikipedia.org/wiki/Mudskipper

    Fish that breath from surface air (modern day fish use labyrinth organs) benefit.
    No I don't. I do accept that fish evolved into amphibians but not entirely convinced that it was soley from random mutations.
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    (Original post by azhao)
    The very fact that you attack Christianity by calling the Bible "some stupid book" shows the limit of your understanding. Does the fact that many prominent geologists and biologists reject the theory of evolution and support creationism mean anything to you? Don't just say you haven't heard of any because of the way the media distorts our views on things by taking sides and not publishing things, its all on the web if you googled it.
    Er, decent biologists do not reject evolution.

    (Original post by evaki)
    ok, have you read about it before? How can you be so sure I can find many examples in books if I wanted to?
    It could very well be that I can, but are you assuming that just because you believe the scientists to be correct, or because you've actually seen it yourself?
    I think if biologists had found an organ which couldn't have evolved through gradual steps they would have told everyone. A discovery like that would make a scientist extremely famous.

    If you want to find out about the evolution of lungs, look on google or read a book.
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    (Original post by nolongerhearthemusic)
    Er, decent biologists do not reject evolution.
    That's what I was saying about the perception the media gives. The media accepts evolution therefore those that reject it are shown in a bad light and aren't seen to be "decent" because of it.
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    (Original post by evaki)
    how about lungs as someone pointed out?
    There aren't any useless stages of the development of the lungs as far as I know. They aren't present in life with a big surface to volume ratio, fish generally have gills (or some kind of lung, like the lungfish), and animals have various different types of lungs that all function well. Unless I've missed your point completely.
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    (Original post by azhao)
    The very fact that you attack Christianity by calling the Bible "some stupid book" shows the limit of your understanding. Does the fact that many prominent geologists and biologists reject the theory of evolution and support creationism mean anything to you? Don't just say you haven't heard of any because of the way the media distorts our views on things by taking sides and not publishing things, its all on the web if you googled it.
    they don't reject evolution and before you go oh what do you know, i study evolution as part of my degree
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    I don't see how it is possible to call yourself a scientist at all and "reject" the theory of evolution, anymore than as a biologist I would say that I "reject" the big bang theory. I might question aspects of it, maybe even the entire basis of the theory but if a scientist "rejects" a theory as important and with as much evidence as evolution is not a scientist, they are a charlatan. Being a scientist is not a job title, it is a philosophy.

    phil.
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    (Original post by azhao)
    That's what I was saying about the perception the media gives. The media accepts evolution therefore those that reject it are shown in a bad light and aren't seen to be "decent" because of it.
    They are seen in a 'bad light' because they are bad scientists.
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    Scientifically speaking, a theory is a well substantiated idea that explains aspects of the natural world. Unfortunately other definitions of theory (such as a “guess” or a “hunch”) cause a great deal of confusion in the non-scientific world when dealing with the sciences. They are, in fact, two very different concepts.
 
 
 
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