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  1. #46
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    ID proponents often claim the human eye is an example of irreducible complexity.

    Here's a recent news story at Science Daily about a new study on the evolution of vision:

    New Study Sheds Light On How and When Vision Evolved

    ScienceDaily (Oct. 29, 2012) Opsins, the light-sensitive proteins key to vision, may have evolved earlier and undergone fewer genetic changes than previously believed, according to a new study from the National University of Ireland Maynooth and the University of Bristol published October 29 in Proceedings of the National Academy of Sciences (PNAS) .

    The study, which used computer modelling to provide a detailed picture of how and when opsins evolved, sheds light on the origin of sight in animals, including humans. The evolutionary origins of vision remain hotly debated, partly due to inconsistent reports of phylogenetic relationships among the earliest opsin-possessing animals.

    Dr Davide Pisani of Bristol's School of Earth Sciences and colleagues at NUI Maynooth performed a computational analysis to test every hypothesis of opsin evolution proposed to date. The analysis incorporated all available genomic information from all relevant animal lineages, including a newly sequenced group of sponges (Oscarella carmela) and the Cnidarians, a group of animals thought to have possessed the world's earliest eyes.

    Using this information, the researchers developed a timeline with an opsin ancestor common to all groups appearing some 700 million years ago. This opsin was considered 'blind' yet underwent key genetic changes over the span of 11 million years that conveyed the ability to detect light.

    Dr Pisani said: "The great relevance of our study is that we traced the earliest origin of vision and we found that it originated only once in animals. This is an astonishing discovery because it implies that our study uncovered, in consequence, how and when vision evolved in humans."
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  2. #47
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    ^^so is this an insect or what?

  3. #48
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    hmm, I guess this could somewhat loosely fall under irreducible complexity. But like you got carnivores, herbivores, and omnivores. It's a complete digestive system intact, and kinda impossible to go from one to another. Can anything be taken from this idea?

    Although I guess if it was all omnivores to begin with, maybe I can see its possible to go from omnivore to herbivore/carnivore. thoughts?

    **although maybe now I think of it, the first organisms must have been eating only plants/fungus, since I'm assuming that stuff must have arose first, since it is plants/fungus rather than animals which can grow and reproduce strictly from the sun's energy. I don't know. I'm just thinking out loud. thoughts?
    Last edited by nastynice; 11-06-2012 at 02:36 PM.

  4. #49
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    ^^anyone?

  5. #50
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    I have no idea where you're trying to go with what you posted.


  6. #51
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    Yeah, it's unclear -- and also just changing the subject without addressing the point.
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  7. #52
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    Quote Originally Posted by debo View Post
    I have no idea where you're trying to go with what you posted.
    I think he's wondering how variability exists in regards to mammalian diets and digestive systems.

    Quote Originally Posted by nastynice View Post
    hmm, I guess this could somewhat loosely fall under irreducible complexity. But like you got carnivores, herbivores, and omnivores. It's a complete digestive system intact, and kinda impossible to go from one to another. Can anything be taken from this idea?

    Although I guess if it was all omnivores to begin with, maybe I can see its possible to go from omnivore to herbivore/carnivore. thoughts?

    **although maybe now I think of it, the first organisms must have been eating only plants/fungus, since I'm assuming that stuff must have arose first, since it is plants/fungus rather than animals which can grow and reproduce strictly from the sun's energy. I don't know. I'm just thinking out loud. thoughts?
    First off, I don't understand why you seem to think that feeding strategies are set in stone and that it's impossible to go from a herbivore to a carnivore. Secondly, I don't seem to understand why you seem to think that digestive tracts were entirely adapted 100% for one diet instead of it being a gradual selective process. Thirdly, I don't understand why you think it's more sensible for one to go from being an omnivore to a carnivore/herbivore when evolution is essentially random and doesn't think ahead. Wouldn't it make more sense for all animals to start off as herbivores and then selective pressures forced them to change their diet and as a result the phenotypic traits that go along with that?

    Rather than writing pages and pages of text, the answer is that it's basically through the evolution of the coelom and natural selection.

    And to be brutally honest, most of your questions can simply be answered by understanding basic natural selection.

    Quote Originally Posted by DenButsu View Post
    Yeah, it's unclear -- and also just changing the subject without addressing the point.
    All of his questions are similar to the ones found on Christian apologetic websites. It's nothing but a Gish Gallop and when this topic comes up once again he'll say that no one has adequately refuted his issues with evolution and continue to ask the same old questions once again. We've all seen this act one too many times.
    Last edited by Freakazoid; 11-10-2012 at 07:09 AM.

  8. #53
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    Quote Originally Posted by debo View Post
    I have no idea where you're trying to go with what you posted.
    Quote Originally Posted by DenButsu View Post
    Yeah, it's unclear -- and also just changing the subject without addressing the point.
    Quote Originally Posted by Freakazoid View Post
    All of his questions are similar to the ones found on Christian apologetic websites. It's nothing but a Gish Gallop and when this topic comes up once again he'll say that no one has adequately refuted his issues with evolution and continue to ask the same old questions once again. We've all seen this act one too many times.
    I'm not trying to "go anywhere" with what I wrote, its just me asking questions out loud. I don't have any personal agenda against evolution, I don't care to prove it right or wrong, I'm just honest to god skeptical yet curious about evolution. That's all there is to it. Gaining knowledge about evolution is as deep as my personal agenda goes in these threads.

    I realize this, for whatever reason, makes some people personally angry at me. But at the same time, some people are willing to drop knowledge. So really, I'm here to gain that new (to me) knowledge. If that offends certain people, then thats their issue

    **and no, this is not something I picked up from a creation website, this is my own original thought which I picked up from reading this thread. but thanks
    Last edited by nastynice; 11-10-2012 at 10:08 AM.

  9. #54
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    Quote Originally Posted by Freakazoid View Post
    I think he's wondering how variability exists in regards to mammalian diets and digestive systems.



    First off, I don't understand why you seem to think that feeding strategies are set in stone and that it's impossible to go from a herbivore to a carnivore. Secondly, I don't seem to understand why you seem to think that digestive tracts were entirely adapted 100% for one diet instead of it being a gradual selective process. Thirdly, I don't understand why you think it's more sensible for one to go from being an omnivore to a carnivore/herbivore when evolution is essentially random and doesn't think ahead. Wouldn't it make more sense for all animals to start off as herbivores and then selective pressures forced them to change their diet and as a result the phenotypic traits that go along with that?

    Rather than writing pages and pages of text, the answer is that it's basically through the evolution of the coelom and natural selection.

    And to be brutally honest, most of your questions can simply be answered by understanding basic natural selection.
    Here's the thing, to answer the last question of the long paragraph, if an animal is an herbivore, how can they possibly become carnivore through natural selection? Because having a digestive tract designed to process particular food, how could it all of a sudden accept another kind?

    For example, if we as humans eat grass, it doesn't help us in anyway, our body simply can't process it. So how could natural selection possibly lead us down this path? The intact digestive system is way to complex for me to think that a "random mutation", along with the forces of natural selection, can all of a sudden make a body accept grass as part of the diet.

    It can make sense for omnivore to eventually evolve into herbivore or carnivore because lets say we got a population, and half splits off to an area that is rich in vegetarian diet, and the other rich in animal diet. Well, over time maybe each population's digestive system starts adapting to its own particular diet that its being exposed to, and over time maybe the digestive system is now more and more specialized in processing either plant or animal. So eventually, it can become specialized to the point where it doesn't accept the other type of diet, resulting in an herbivore or carnivore.

    But you see how this doesn't make sense for let's say going from herbivore to carnivore? Because how can that animal's digestive tract even start accepting the other type of diet, much less over such a sustained period of time to allow natural selection start making its digestive system specialized. Do you get what I'm trying to say?

    And I kinda tied this back to IC, because it seems like an IC based idea

    *maybe one possible explanation is mammals came to be as omnivores. Maybe when we were bugs (whatever), the digestive system was way more simple, and could mutate from herbivore to omnivore. And so we were omnivores before ever even evolving into these more complex mammals.
    Last edited by nastynice; 11-10-2012 at 10:12 AM.

  10. #55
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    Quote Originally Posted by nastynice View Post
    Here's the thing, to answer the last question of the long paragraph, if an animal is an herbivore, how can they possibly become carnivore through natural selection? Because having a digestive tract designed to process particular food, how could it all of a sudden accept another kind?

    if we as humans eat grass, it doesn't help us in anyway, our body simply can't process it. So how could natural selection possibly lead us down this path? The intact digestive system is way to complex for me to think that a "random mutation", along with the forces of natural selection, can all of a sudden make a body accept grass as part of the diet.
    We wouldn't be able to derive nutrients from grass because for a majority of us, our digestive tract have adapted for a certain type of feeding strategy. However, there may be allele frequencies that may express for a larger digestive tract which has the ability to break down cellulose. Herbivores spent an exorbitant amount of time eating so traits that favor herbivory are not fit in a human society and as a result allele frequencies do not reflect such.

    For example, ~90% of Tibetans (environment ~4000m) express high oxygen saturation genotype versus ~9% of Han Chinese. Our physiological differences are merely a function of our environment and our genes.

    As well, a digestive tract is not too complex for mutagenic changes. This is a lack of imagination on your part. And for the second time, mutation is not the only mechanism of change. You don't necessarily need a mutated genotype in order to create phenotypical differences.

    Quote Originally Posted by nastynice View Post
    It can make sense for omnivore to eventually evolve into herbivore or carnivore because lets say we got a population, and half splits off to an area that is rich in vegetarian diet, and the other rich in animal diet. Well, over time maybe each population's digestive system starts adapting to its own particular diet that its being exposed to, and over time maybe the digestive system is now more and more specialized in processing either plant or animal. So eventually, it can become specialized to the point where it doesn't accept the other type of diet, resulting in an herbivore or carnivore.

    But you see how this doesn't make sense for let's say going from herbivore to carnivore? Because how can that animal's digestive tract even start accepting the other type of diet, much less over such a sustained period of time to allow natural selection start making its digestive system specialized. Do you get what I'm trying to say?
    It doesn't make sense because that would imply that evolution is forward thinking. Secondly, it would also imply that all animals with X feeding strategy evolved a certain way. It's completely nonsensical. If it were that easy we wouldn't need phylogenetic trees. Each phyla develops in their own way but for a majority of animals they start off as either carnivores/herbivores and adapt to differing feeding strategies. Most omnivores are a result of a late adaptation and as a result still contain the tools to confer to a carnivorous or a herbivorous diet.

    Quote Originally Posted by nastynice View Post
    And I kinda tied this back to IC, because it seems like an IC based idea

    *maybe one possible explanation is mammals came to be as omnivores. Maybe when we were bugs (whatever), the digestive system was way more simple, and could mutate from herbivore to omnivore. And so we were omnivores before ever even evolving into these more complex mammals.

    IC is the idea that a system is so finely tuned that if you simply remove a single interacting part it'll cease to function. The problem with this idea is that such systems are either impossible or incredibly resistant to evolution because any possible changes can result in malfunction. Such examples are rare and are usually biochemical systems not physiological ones.
    Last edited by Freakazoid; 11-10-2012 at 05:10 PM.

  11. #56
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    Quote Originally Posted by Freakazoid View Post
    We wouldn't be able to derive nutrients from grass because for a majority of us, our digestive tract have adapted for a certain type of feeding strategy. However, there may be allele frequencies that may express for a larger digestive tract which has the ability to break down cellulose. Herbivores spent an exorbitant amount of time eating so traits that favor herbivory are not fit in a human society and as a result allele frequencies do not reflect such.
    So ONE genetic change can lead to an animal being able to properly digest and pull the nutrients from a food source it previously couldn't?

    Quote Originally Posted by Freakazoid View Post
    For example, ~90% of Tibetans (environment ~4000m) express high oxygen saturation genotype versus ~9% of Han Chinese. Our physiological differences are merely a function of our environment and our genes.

    As well, a digestive tract is not too complex for mutagenic changes. This is a lack of imagination on your part. And for the second time, mutation is not the only mechanism of change. You don't necessarily need a mutated genotype in order to create phenotypical differences.
    Yea, I know, I mean random mutation/different genetic expression, along with the forces of natural selection. Basically, whatever it is that leads to changes throughout a population.



    Quote Originally Posted by Freakazoid View Post
    It doesn't make sense because that would imply that evolution is forward thinking. Secondly, it would also imply that all animals with X feeding strategy evolved a certain way. It's completely nonsensical. If it were that easy we wouldn't need phylogenetic trees. Each phyla develops in their own way but for a majority of animals they start off as either carnivores/herbivores and adapt to differing feeding strategies. Most omnivores are a result of a late adaptation and as a result still contain the tools to confer to a carnivorous or a herbivorous diet.
    No, I'm definitely not implying such, I think there's a misunderstanding.


    Quote Originally Posted by Freakazoid View Post
    IC is the idea that a system is so finely tuned that if you simply remove a single interacting part it'll cease to function. The problem with this idea is that such systems are either impossible or incredibly resistant to evolution because any possible changes can result in malfunction. Such examples are rare and are usually biochemical systems not physiological ones.
    I don't know if I'm saying the digestive tract is so finally tuned that removing a single part will make it cease to function (we can literally cut out a person's small intestines and they're digestive tract can still function). I'm just saying with so many interacting parts working in harmony, its hard to see how it can adapt from one to the other.

    I'm thinking that multiple changes would be required for an animal to go from herbivore to carnivore/omnivore. The thing I'm getting at is, lets say it takes ten genetic changes to go from herbivore to omnivore. How is it that lets say the first change would become the norm in a population, as I don't see what benefit that first change could provide and cause it to become spread out through the population in the first place. This would have to happen 10 times, a genetic change becoming the norm in the population, when each change seemingly provides no benefit.

    Well, I'm not necessarily schooled on how the digestive system evolved or anything like that, but I'm assuming that carnivores absolutely cannot process plant diet, and herbivores absolutely cannot process meat diet.

  12. #57
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    Quote Originally Posted by nastynice View Post
    So ONE genetic change can lead to an animal being able to properly digest and pull the nutrients from a food source it previously couldn't?



    Yea, I know, I mean random mutation/different genetic expression, along with the forces of natural selection. Basically, whatever it is that leads to changes throughout a population.





    No, I'm definitely not implying such, I think there's a misunderstanding.




    I don't know if I'm saying the digestive tract is so finally tuned that removing a single part will make it cease to function (we can literally cut out a person's small intestines and they're digestive tract can still function). I'm just saying with so many interacting parts working in harmony, its hard to see how it can adapt from one to the other.

    I'm thinking that multiple changes would be required for an animal to go from herbivore to carnivore/omnivore. The thing I'm getting at is, lets say it takes ten genetic changes to go from herbivore to omnivore. How is it that lets say the first change would become the norm in a population, as I don't see what benefit that first change could provide and cause it to become spread out through the population in the first place. This would have to happen 10 times, a genetic change becoming the norm in the population, when each change seemingly provides no benefit.

    Well, I'm not necessarily schooled on how the digestive system evolved or anything like that, but I'm assuming that carnivores absolutely cannot process plant diet, and herbivores absolutely cannot process meat diet.
    To put it simply some are new adaptions from natural selection, some are from genetic mutations and others are from exaptation (i.e fish lungs became gall bladder for many vertebrates). If the first change makes the function marginally more effective then it'll be selected for.
    Last edited by Freakazoid; 11-13-2012 at 08:05 PM.

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    Quote Originally Posted by Freakazoid View Post
    To put it simply some are new adaptions from natural selection, some are from genetic mutations and others are from exaptation (i.e fish lungs became gall bladder for many vertebrates). If the first change makes the function marginally more effective then it'll be selected for.
    lungs becoming gall bladder? definitely the first time i've heard of that.

    I see what you're saying. My point was that how could a purely herbivore digestive tract become marginally more effective in a manner allowing for digesting meat? But now that I think about it more, really its just way too complex a system for me to really make that statement. I understand now what you mean by me implying evolution is forward thinking.

  14. #59
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    That last image in Attenborough's clip of the human eye... kind of cool to think about the role that the beauty of eyes played in the current state of our eyes. What if there were totally awesome eyes that saw other-worldy colors and shot lasers and ****, but were so ugly that no person wanted to have sex with someone with it.

    Pure Sex.

    you have fun with your properly evaluated medical studies....i'll believe my garbage. you believe yours.

  15. #60
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    Quote Originally Posted by giventofly View Post
    That last image in Attenborough's clip of the human eye... kind of cool to think about the role that the beauty of eyes played in the current state of our eyes. What if there were totally awesome eyes that saw other-worldy colors and shot lasers and ****, but were so ugly that no person wanted to have sex with someone with it.
    Sexual selection, and why certain things are appealing to certain species, is really interesting.
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