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Thread: Intelligent design and the monkfish

  1. #1 Intelligent design and the monkfish 
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    ok don't freak out, I'm not about to advocate intelligent design, however:

    a girl I know was telling me today how she'd heard about intelligent design as a legitimate science (I immediately protested), but she was really making the argument of academics who cannot give an account for certain characteristics on certain species.

    The only example she could give me was of the angler fish (a lophiiforme with the monkfish) which has an antennae which it uses to lure other fish and then eats. How could such an antennae evolve cumulatively? "It couldnt, it must have been designed."

    I didnt have an answer, hence why I'm here, can anyone give me an evolutionary account of how this happened and such an antenna evolved?

    If you really cant, I will settle for an adequate possibility of how it happened!



    PS, I am fully aware that this sounds like any other intelligent design argument, I'm not supporting intelligent design in any way and don't want this thread to digress onto a debate on it!


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  3. #2  
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    I'll start by admitting I know little about marine biology or the species in question, but that the evolution of this trait is fairly easy to explain. Fluorescent proteins are common enough in nature and can been seen in many very diverse species. In a dark, deep sea environment, there would be a selective advantage in favour of a predatory fish that could mimic small prey by having high visibility fluorescent spots. There would also be a selective advantage in favour have having reletively few of these (preferably just one), so that the result is not simply a great big shiny outline of the proto-angler fish. Most fish species have fairly pronounced vertebral spines of some nature, usually as part of their dorsal fin. Since most fish have some muscle control over those spines, there would be an advantage to that fluorescent spot migrating to some part of one of the spines. That sort of locational change can happen in one step without needing transition from it's original location. There will now, in some cases, be a selective pressure upon that spine to become extended so that the fish can manipulate it more. And there we have our angler fish.

    The actual evolution of the fish may have gone nothing like that at all, there are probably many routes through evolution to that goal. But the above is a plausible means to go from general monkfish to angler fish and thus invalidates the "intelligent design" argument for that particular species. Essentially, we don't need to invoke a miracle.


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    Forum Cosmic Wizard paralith's Avatar
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    Hi Robbie, this is a common ID tactic, to say that a certain trait couldn't have evolved bit by bit, because it is ONLY functional in it's existing form. This is simply a falsehood. A common analogy is a car motor - it can only function as a car motor exactly the way it exists - if anything was different, it wouldn't work. True, it wouldn't work as a car motor. But that doesn't mean it wouldn't have ANY function. You could use a piece of it as a paperweight, for instance.

    The same goes in biological system. One structure that originally had a different purpose can be combined with others to create a new structure with a new purpose. Going back to the monkfish, it's ancestors probably lay hiding and waited for a prey fish to come along, and then jumped out and ate it. Now, some of these ancestors developed a mutation that made one of the ribs of it's dorsal fin grow longer and closer to the top of its head. Some prey fish became a little curious about that rib sticking out, and would head toward the waiting monkfish - so these monkfish had more food, and greater reproductive success than monkfish without that mutation. And the longer the rib, the more prey fish were curious about it. So always the individuals with the longest rib had the greatest success, and over time the antennae we see today developed.

    Remember that evolution works on averages. If, on average, monkfish individuals with a longer fin rib have greater reproductive success than other monkfish, that longer rib trait will be favored in the population. It didn't have to right away exist in its modern day form - it just had to be a little better at getting food than fish who didn't have it.
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    I totally agree and I'm not about to through evolution out the window on the back of a monkfish! I would at this point assume there is a good way by which it happened via evolution.

    What interested me is that she was trying to make it sounds like ID and evolution are compatible and that all that's going on is that there is some intelligent "intention" pushing for certain characteristics to develop. I see this as the environment and see no reason to suspect such a thing. And in particular why would an "intelligence" concern itself when our own human evolution is so well accounted for it needs no such thing!

    I really think that she doesn't understand the details of the theory which is probably what made her hard to convince.

    Thanks for your input anyway, I never thought of dorsal fins migrating, I was waondering where something like that would come from!
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    Hi Paralith, I totally understand what you are saying BUT, taking the anglerfish as an example, out of the whole anglerfish population, how many of them would need a certain mutation in order that it might be passed on, and have an affect on that whole population ?

    blikin' 'eck, I hope that makes sense ?

    BARCUD
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    Forum Cosmic Wizard i_feel_tiredsleepy's Avatar
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    They used to say the same thing about bacterial flagella, until it was discovered that the flagellum was very similar to type 3 secretory system.

    Also, it ignores the concept of exaptation.
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    hey everyone, yeah ok read up and it turns out it is from migration of the anterior dorsal fin, some use it as a clubbing device, other species use it as a bioluminescent lure to attract other fish.
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    Quote Originally Posted by BARCUD
    Hi Paralith, I totally understand what you are saying BUT, taking the anglerfish as an example, out of the whole anglerfish population, how many of them would need a certain mutation in order that it might be passed on, and have an affect on that whole population ?

    blikin' 'eck, I hope that makes sense ?

    BARCUD
    It depends a lot on strength of selection. Some mutations are more common than others - if we take the example of fin spines, perhaps there isn't strong selection to keep them in a specific area, so mutations that move them around to different places and/or make them slightly different in length are relatively common. Also, if the mutation that occurs offers a very strong selective benefit, just one or two fish with that mutation might have that many more offspring than fish who don't have it.

    Some traits also just have natural variation, and a change in the environment cause one extreme of that variation to have a benefit it might not have had before.
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
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    actually, I'm getting quite interested in this now. I've just read that the male anglerfish as an adult gets a bit strange.

    It's digestive system degenerates so it cant eat. Then it latches onto a female and bites her, and lives off her fat etc. but then it dies and its whole body degenerates/disintegrates and nothing is left but the gonads which the female then uses (at her discretion!?) to reproduce with...

    How the hell can u explain that?!?!?!?
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  11. #10  
    Forum Cosmic Wizard paralith's Avatar
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    I explain that through the extreme difficulty these fish have finding mates. They live in the deep sea with little to no light, and not a lot of prey to go around. If a female is going to garner enough resources to produce eggs (which are expensive gametes to make), then she needs to have a wide range with few other competitors of her own species in which she can feed.

    Males, on the other hand, just need to make sperm, and making sperm is easy. The hard part for the males is finding a female. And if you find one, she might not even be old enough to reproduce yet. So instead of wasting a lot of time wandering the deep ocean looking for fertile females, and needing to keep yourself alive that whole time by feeding, which is hard enough as it is, just zero in on one female and stick with her even if she's not old enough to breed yet.

    All that matters is that your sperm is used, and in that case, all the female needs is your gonads. And, if food is hard enough to get for one angler fish, getting food to support two angler fish in one spot is probably impossible. So the males whither away until all that's left is what's important, allowing the female time to eat and grow.
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
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    Robbie, and perhaps Barcud too,

    Besides Paralith's excellent explanations regarding mutation and selection, there might be one other thing to consider too.

    Suppose, for purposes of argument, that there genuinely was a telos to evolution, as the IDers claim.

    One of the consequences, we must suppose, is that if it can make big leaps from one form to another - such a the human eye, or the bacterial motor, or even the anglerfish lure - then there is a reason for its making such leaps and not others. We can ask for a reason because we have already assumed a telos. This is not something we can legitimately do with Natural Selection as we do not attribute to it a goal-directed intelligence.

    What possible reason could the ID Telos have for, in one jump, creating the anglerfish lure, but yet prove entirely incapable of doing the same thing with the human vas deferens, for instance, which takes notoriously the most tortuous and vulnerable route from testes to penis, which can only be explained by incremental, thoughtless, changes over generations.

    Therefore, for every alleged example provided by IDers, of "irreducible complexity" (almost all of which - check talk.origins and others for references - have been satisfactorily refuted) there are many more examples of thoughtlessnes, and lack of telos, in evolution for which they have no answer.

    In humans alone, besides the vas deferens problem there is the issue of the front-to-back nature of our retinas: light has to pass through the base of the nerve cells before it gets to the light sensitive portions. Yet squids have it the right way around. And what does our vermiform appendix do, anyway, to make up for all the discomfort and danger it can subject us to? And...

    we could go on and on and on.

    Dawkins and others have suggested that this ID notion is quite clearly a logical fallacy - it is the argument from incredulity - because IDers cannot see how a feature could have evolved, they claim it is impossible.

    An argument regarding genuine irreducible complexity would not take this form.

    If there were an organ of genuinely irreducible complexity - with no possible explanation of "this is how you get from there to her" - then natural selection cannot be used as an explanation for it. But this demonstration of impossibility is far stricter than the demonstrattioon of limited imagination (the argument from incredulity). But the latter is the only argument the IDers have for now....
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  13. #12  
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    Quote Originally Posted by sunshinewarrior
    Robbie, and perhaps Barcud too,

    Besides Paralith's excellent explanations regarding mutation and selection, there might be one other thing to consider too.

    Suppose, for purposes of argument, that there genuinely was a telos to evolution, as the IDers claim.

    One of the consequences, we must suppose, is that if it can make big leaps from one form to another - such a the human eye, or the bacterial motor, or even the anglerfish lure - then there is a reason for its making such leaps and not others. We can ask for a reason because we have already assumed a telos. This is not something we can legitimately do with Natural Selection as we do not attribute to it a goal-directed intelligence.

    What possible reason could the ID Telos have for, in one jump, creating the anglerfish lure, but yet prove entirely incapable of doing the same thing with the human vas deferens, for instance, which takes notoriously the most tortuous and vulnerable route from testes to penis, which can only be explained by incremental, thoughtless, changes over generations.

    Therefore, for every alleged example provided by IDers, of "irreducible complexity" (almost all of which - check talk.origins and others for references - have been satisfactorily refuted) there are many more examples of thoughtlessnes, and lack of telos, in evolution for which they have no answer.

    In humans alone, besides the vas deferens problem there is the issue of the front-to-back nature of our retinas: light has to pass through the base of the nerve cells before it gets to the light sensitive portions. Yet squids have it the right way around. And what does our vermiform appendix do, anyway, to make up for all the discomfort and danger it can subject us to? And...

    we could go on and on and on.

    Dawkins and others have suggested that this ID notion is quite clearly a logical fallacy - it is the argument from incredulity - because IDers cannot see how a feature could have evolved, they claim it is impossible.

    An argument regarding genuine irreducible complexity would not take this form.

    If there were an organ of genuinely irreducible complexity - with no possible explanation of "this is how you get from there to her" - then natural selection cannot be used as an explanation for it. But this demonstration of impossibility is far stricter than the demonstrattioon of limited imagination (the argument from incredulity). But the latter is the only argument the IDers have for now....
    Good post. I just blogged on a similar argument yesterday. Pointing to irreducible complexity as evidence of design is actually a wonderful example of IDers shooting themselves in the foot. Throughout the biochemical cascades we see "irreducibly complex" systems (with critical steps that are vulnerable to mutation) side by side with massive redundancy (where systems have multiple back-ups). This would almost make sense if the presence of redundancy related at all to the relative importance of systems from a design point of view, but this is not the case. If we assume that irreducibly complex cascades, such as Michael Behe's example of the blood clotting cascade, are actually designed elements, then the designer is a negligent idiot.
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    i've posted the following rebuttal of the logical fallacies committed in the standard ID argument on another forum :

    a typical argument of Intelligent Design runs as follows :

    X is unexplained by Darwin's theory of natural selection. It is unresolvable because it is a problem of irreducible complexity. Since natural selection can't solve the problem, this calls for a designer.

    when we have a closer look at this argument, we see the following gaps in the logic :

    1. equating unresolved with unresolvable
    science is always full of gaps where the current status of knowledge doesn't know the answer yet - it's what keeps scientific enquiries going, but the operating word is not yet
    2. irreducible complexity is postulated, not proven
    by irreducible complexity is meant that various complex parts need to be present and interact in specific, complex ways for X to work properly (i.e. in ID's view of the world, it's all or nothing) - this is ignoring several cases of exaptation, items that are present but used for a different purpose, and later on co-opted to play a part in the new complex activity (in short, the all or nothing scenario has many times over been proven to be no more than a straw man)
    3. the false duality [NOT A = B]
    in maths it is well known that if you can't directly prove that A is true, then you can try and follow a more indirect route
    you prove that there is 1 and is only 1 solution
    you prove that there's only 2 possible solutions A and B
    you prove that B is not true
    conclusion = A must be true
    ID presents the situation as if only natural selection or Intelligent Design can explain some natural phenomenon, claim to prove that natural selection doesn't explain the phenomenon, hence ID must be the correct explanation, hence even if they managed to prove natural selection powerless, Intelligent Design could not be accepted as a suitable alternative until there was positive proof for it
    apart from not really proving anything about natural selection's power of explanation, ID people also fail to prove that no other explanation but natural selection and Intelligent Design is possible
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
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    Yeah, it's like shooting fish really.
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    Interesting subject and the type of thread one can learn from.
    Also noted is the absence of idiots (I'm arrogant enough to include myself as a "non-idiot"), trolls, and those with a "wacky" sense of humour.
    Well, I am feeling a bit grumpy today!
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  17. #16  
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    My favourite example of intelligent design is hemorrhoids. I would just love to go to heaven to meet the God who created man in its own imagine, complete with the purposefully sloppy design of the bloodvessels in the rectum regarding the upright mode of locomotion.

    It is indeed a god who knows the meaning of fun, when he designed his own arse for walking on all four limbs instead of standing upright.

    Or did he just mean for man to bend down before him at all times and just designed a system that automatically punishes all men who do not?
    "Kill them all and let God sort them out."

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  18. #17  
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    hahaha, brilliant
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  19. #18  
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    Quote Originally Posted by sunshinewarrior
    Robbie, and perhaps Barcud too,

    Besides Paralith's excellent explanations regarding mutation and selection, there might be one other thing to consider too.

    Suppose, for purposes of argument, that there genuinely was a telos to evolution, as the IDers claim.

    One of the consequences, we must suppose, is that if it can make big leaps from one form to another - such a the human eye, or the bacterial motor, or even the anglerfish lure - then there is a reason for its making such leaps and not others. We can ask for a reason because we have already assumed a telos. This is not something we can legitimately do with Natural Selection as we do not attribute to it a goal-directed intelligence.

    What possible reason could the ID Telos have for, in one jump, creating the anglerfish lure, but yet prove entirely incapable of doing the same thing with the human vas deferens, for instance, which takes notoriously the most tortuous and vulnerable route from testes to penis, which can only be explained by incremental, thoughtless, changes over generations.

    Therefore, for every alleged example provided by IDers, of "irreducible complexity" (almost all of which - check talk.origins and others for references - have been satisfactorily refuted) there are many more examples of thoughtlessnes, and lack of telos, in evolution for which they have no answer.

    In humans alone, besides the vas deferens problem there is the issue of the front-to-back nature of our retinas: light has to pass through the base of the nerve cells before it gets to the light sensitive portions. Yet squids have it the right way around. And what does our vermiform appendix do, anyway, to make up for all the discomfort and danger it can subject us to? And...

    we could go on and on and on.

    Dawkins and others have suggested that this ID notion is quite clearly a logical fallacy - it is the argument from incredulity - because IDers cannot see how a feature could have evolved, they claim it is impossible.

    An argument regarding genuine irreducible complexity would not take this form.

    If there were an organ of genuinely irreducible complexity - with no possible explanation of "this is how you get from there to her" - then natural selection cannot be used as an explanation for it. But this demonstration of impossibility is far stricter than the demonstrattioon of limited imagination (the argument from incredulity). But the latter is the only argument the IDers have for now....
    As far as the human eye is concerned is that the ultra-violet rays would make us blind in a very short time, the squids live in the ocean which blocks the rays.
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  20. #19  
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    Quote Originally Posted by mastmec
    As far as the human eye is concerned is that the ultra-violet rays would make us blind in a very short time, the squids live in the ocean which blocks the rays.
    Maybe I'm picking you up wrong here but are you suggesting the inversion is a designed benefit? Got any evidence?

    As I understand it, the tissue over our retina should offer negligible protection from UV light (too thin). Also, the covering tissue consists of neurons, which I'm sure would be susceptible to UV damage also (assuming it is the significant risk you make it out to be). So your "protective covering", if damaged, renders us blind due to nerve damage. Unless you can give me some specific evidence on this idea I'm gonna go ahead and say your explanation does not float.
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    Quote Originally Posted by TheBiologista
    Quote Originally Posted by mastmec
    As far as the human eye is concerned is that the ultra-violet rays would make us blind in a very short time, the squids live in the ocean which blocks the rays.
    Maybe I'm picking you up wrong here but are you suggesting the inversion is a designed benefit? Got any evidence?

    As I understand it, the tissue over our retina should offer negligible protection from UV light (too thin). Also, the covering tissue consists of neurons, which I'm sure would be susceptible to UV damage also (assuming it is the significant risk you make it out to be). So your "protective covering", if damaged, renders us blind due to nerve damage. Unless you can give me some specific evidence on this idea I'm gonna go ahead and say your explanation does not float.
    I just gave you a little evidence and you want me to expand on it now, why don't you look into it a little for yourself. As far as the "the protective covering" all eyes are delicate, but if you can design one a little better, be my guest.
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  22. #21  
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    Quote Originally Posted by mastmec
    I just gave you a little evidence and you want me to expand on it now, why don't you look into it a little for yourself. As far as the "the protective covering" all eyes are delicate, but if you can design one a little better, be my guest.
    mastmec, though this is not an official forum rule, it is common courtesy in scientific debates for each person to provide the supporting information for the points that they make if requested to do so. That is what most members do and what most members expect, so I would just like to warn you that you can expect to be greeted with skepticism if you are not willing to provide source material. /moderator mode
    Man can will nothing unless he has first understood that he must count on no one but himself; that he is alone, abandoned on earth in the midst of his infinite responsibilities, without help, with no other aim than the one he sets himself, with no other destiny than the one he forges for himself on this earth.
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  23. #22  
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    Quote Originally Posted by mastmec
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by mastmec
    As far as the human eye is concerned is that the ultra-violet rays would make us blind in a very short time, the squids live in the ocean which blocks the rays.
    Maybe I'm picking you up wrong here but are you suggesting the inversion is a designed benefit? Got any evidence?

    As I understand it, the tissue over our retina should offer negligible protection from UV light (too thin). Also, the covering tissue consists of neurons, which I'm sure would be susceptible to UV damage also (assuming it is the significant risk you make it out to be). So your "protective covering", if damaged, renders us blind due to nerve damage. Unless you can give me some specific evidence on this idea I'm gonna go ahead and say your explanation does not float.
    I just gave you a little evidence and you want me to expand on it now, why don't you look into it a little for yourself. As far as the "the protective covering" all eyes are delicate, but if you can design one a little better, be my guest.
    How would you describe the 'inverted' eye design of fish that live at the same depths or below, as squids?
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    Fish are vertebrates, all have inverted eyes. Still, no evidence exists to support the claim that even the most advanced verted eye is superior to the inverted eye.
    Although cephalopods can perceive shape, light intensity, and texture, they lack many of the advantages of an inverted retina, such as the ability to perceive small details. The visual system of the cephalopods is designed very differently than the inverted eye in other ways to enable them to function in their dark, water world. They can see only in black and white and have a narrow range of vision compared to humans. Their photoreceptor cell population is composed of only rods, and they contain a mere 20 million retina receptor cells compared to 126 million in humans.
    If the human retina were verted, we have no evidence that vision would be better. Most likely it would be worse. Comparisons of different eyes are difficult to make because, although the quality of the image projected on the retina can be evaluated by a study of the lens system’s optical traits, we lack direct knowledge about the actual image produced in the brain.
    Instead of being a great disadvantage, or a “curse” or being incorrectly constructed, the inverted retina is a tremendous advance in function and design compared with the simple and less complicated verted arrangement. One problem amongst many, is to explain how this abrupt major retinal transformation from the verted type in invertebrates to the inverted vertebrate model came about as nothing in paleontology offers any support.
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  25. #24  
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    Quote Originally Posted by mastmec
    Quote Originally Posted by TheBiologista
    Quote Originally Posted by mastmec
    As far as the human eye is concerned is that the ultra-violet rays would make us blind in a very short time, the squids live in the ocean which blocks the rays.
    Maybe I'm picking you up wrong here but are you suggesting the inversion is a designed benefit? Got any evidence?

    As I understand it, the tissue over our retina should offer negligible protection from UV light (too thin). Also, the covering tissue consists of neurons, which I'm sure would be susceptible to UV damage also (assuming it is the significant risk you make it out to be). So your "protective covering", if damaged, renders us blind due to nerve damage. Unless you can give me some specific evidence on this idea I'm gonna go ahead and say your explanation does not float.
    I just gave you a little evidence and you want me to expand on it now, why don't you look into it a little for yourself. As far as the "the protective covering" all eyes are delicate, but if you can design one a little better, be my guest.
    The burden of proof is upon you mastmec. You've made an assertion, so back it up or retract it.
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  26. #25  
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    Quote Originally Posted by mastmec
    Fish are vertebrates, all have inverted eyes. Still, no evidence exists to support the claim that even the most advanced verted eye is superior to the inverted eye.
    Not true, humans and other species with inverted retinas have a blind spot in their vision due to the inversion. This is not present in cephalopod eyes. Aide from that, the differences seem insignificant except in exceptional (and impractical) circumstances. But that lack of any practical difference begs the question: why have a difference at all?

    Quote Originally Posted by mastmec
    Although cephalopods can perceive shape, light intensity, and texture, they lack many of the advantages of an inverted retina, such as the ability to perceive small details.
    That is not a trait related to inversion of the retina or the lack of it. Why would it be? There are many species with inverted retina with similarly limited sight capabilities.

    Quote Originally Posted by mastmec
    The visual system of the cephalopods is designed very differently than the inverted eye in other ways to enable them to function in their dark, water world. They can see only in black and white and have a narrow range of vision compared to humans. Their photoreceptor cell population is composed of only rods, and they contain a mere 20 million retina receptor cells compared to 126 million in humans.
    Rod and cone densities are not related to retinal inversion. There are species with inverted retinas that also possess much higher photoreceptor densities than humans. The tawny owl also has only rods, yet has an inverted retina.

    Quote Originally Posted by mastmec
    If the human retina were verted, we have no evidence that vision would be better. Most likely it would be worse.
    That's a silly claim to make. Firstly we do know that inversion gives us a disadvantage (the blind spot). Secondly, if we didn't have such evidence, it wouldn't automatically suggest that the opposite case is true. That's a logical fallacy.

    Quote Originally Posted by mastmec
    Comparisons of different eyes are difficult to make because, although the quality of the image projected on the retina can be evaluated by a study of the lens system’s optical traits, we lack direct knowledge about the actual image produced in the brain.
    We can get a fairly good idea from the parameters you've described.

    Quote Originally Posted by mastmec
    Instead of being a great disadvantage, or a “curse” or being incorrectly constructed, the inverted retina is a tremendous advance in function and design compared with the simple and less complicated verted arrangement.
    Evolution does not equal complexity increase. Complexity increase does not equal advancement or advantage. There's no real reason why we couldn't have the same rod and cone densities as we have now along with a "verted" retina as you put it.

    Quote Originally Posted by mastmec
    One problem amongst many, is to explain how this abrupt major retinal transformation from the verted type in invertebrates to the inverted vertebrate model came about as nothing in paleontology offers any support.
    Simple examination of anatomy and genetics does offer an explanation. The inverted eye probably did not evolve from the "verted" eye. The gross morphologies arose independently. We share photoreceptor design, but the overall eye layout suggests convergence, rather than a common origin. Our eye design with it's drawback arose by chance- it was "good enough" for selection to conserve it. That's all.

    Now, you've still not provided evidence to support your assertion that our inverted retina provides an advantage in itself, nor that it affords us protection from UV light. Can you back up those claims?
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    Forum Professor sunshinewarrior's Avatar
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    Just to thank The Biologista for this response to mastmec. Valid points, well presented.

    Isn't it wonderful how a thread initially about ID leads us by these pathways to consider arguments and evidence for and against considerations of efficviency in design? (One of the books on my bedside table that I occasionally dip into for a re-read is Dennett's Darwin's Dangerous Idea, in which he makes some telling points regarding such matters.)
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