Unintelligent design (recurrent laryngeal nerve)

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I hve found GM to be very close-minded on this topic.

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I have repeated many times only 3 pages of discussion that as of today, there is no proved function of the route the RLN takes. I repeated this in almost all of my posts.

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But of course, since I say that I am confident that, since our knowledge of biology is far from complete, a function will be identified for it, (A situation that has happened at least 100 times in the history of medicine) he has called this smokes and screens.

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The facts of the matter are:1) As you admit there is no known function, nor is there any evidence that the route has a function or is even likely to have a function.2) The route IS explained by evolution.In other words to be "very-closed minded" in your eyes it is simply necessary to prefer to follow the evidence over your opinion.Think very carefully about that.

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As someone said in this thread (don't remember who), the fact that the route is explained by evolution does not prohibit it from having a function. I would even go as far as to say that it wouldn't even be much of a surprise from an evolutionnary perspective either.

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And nobody is arguing that because the route is explained by evolution it cannot also have a purpose. However the fact is that it is very unlikely that the route has a purpose, given our understanding of the nervous system. You cannot even offer even a superficially plausible explanation for the route.If you were honestly looking for an explanation, instead of demanding unethical surgical experiments as traderdrew does you could try looking for the known effects of damage to the nerve. If the route has a function, we should expect damage to the nerve to cause effects in areas which it passes by.

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And so when someone talks as if this idea and radioactive spiders giving me superpowers were analog, I do find it a bit narrow-minded.

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Would that be as closed-minded as completely ignoring the reasons why it is believed that the route does not have a function and setting up a strawman in its place ?

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Looking for the effects of damage could also be foretelling. But damage doesn't necessarily mean destroyed.

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But it should at least give a pointer of where to look for any function dependent on the nerve operating properly.

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Unethical? We have gone at it before PaulK and I know you are no proponent of intelligent design. I would have thought it would have been ethical to correct a mishap of the Darwinian process. Wouldn't you agree? Perhaps you are not so sure the RLN is a result of Darwinian evolution?

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It might seem so to someone who places some abstract idea of perfection above the interests of the patient. However, even if you had a practical means of rerouting the nerve with no significant risk of damaging it (and you don't) major surgery to correct a feature which is merely poorly designed carrying with it some minor risks would be highly questionable in itself.

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I never did make any demands for the surgery.

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Really ? Message 56[quote] I simply assumed perhaps it has been done to an animal with a similar design and since some of you are so sure it is a poor design, you have read about the results of damage or destruction to the nerve. [/qs]Even with animal experiments there are obvious problems. Animals are unable to self-report symptoms, any effects noted could easily be due to side-effects of the surgery, and the surgery would be unable to produce an optimal design anyway. And if we cannot get useful results out of the experiment then it is unethical to perform it even on animals.

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My position is "I do not know" if it is a bad design or not and I proposed a hypothesis. I think you, GrannyMagda and many others insist it is a bad design simply because something wants you to believe this other than evidence.

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But of course the position that it is a poor design IS based on evidence. It is you and slevesque who are are throwing up speculations rather than follow the evidence that we have. Indeed, so far as I can tell the whole basis of your hypothesis - a connection to the aorta - is missing. The recurrent laryngeal nerve branches off the left vagus nerve and loops around the aorta, before ascending again to the larynx.

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I will define that as 'Darwinian dogma'.

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I'll call that "the pot calling the kettle black".

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No it is not, your position is based on the assumption that a designer would have never designed it that way. You assume your knowledge of science covers all ignorance on the subject and you know enough about this network of nerves to make this determination. I say you don't know enough.

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But of course, that is just your assumption. Just as you assumed a connection to the aorta.The fact is that the nerve takes a long, meandering path from the brain to the larynx, and there is no sign that it needs to do so. Damage to the nerve shows symptoms relating to the larynx, not to anything else. There are no signs of other connections (or any sensible reason for other connections) on offer.

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I also know from previous debates that you have to get the last word PaulK. You can have it because I have drilled my point here.

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By which you mean that I don't like to let falsehoods go unanswered.

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I gave a superficially plausible explanation in the beginning, but they are not permitted it seems. Even if it is logically plausible, and even if they are presented as a genuine guess (and not as any sort of fact)

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I've reviewed the thread and you didn't give any explanation other than speculating that changes in the diameter of the aorta might do something.

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I would be interesting to know what are those reasons to think it has no function ?

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The lack of any connections other than to the larynx is a big one. The fact that we don't see any significant symptoms affecting anything but the larynx when the nerve is damaged is another.What's your reason for thinking that we don't know enough to come to a conclusion ?

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A reasonable speculation from a layman such as me in this domain.

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Just as when you remove the appendix, no apparent symptoms. This does not mean that it has no function.

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Except, of course, that we are measuring actual symptoms resulting from damage. And of course, evidence that falls short of proof is still evidence.

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Well, since entering this discussion, I have been searching for research on this. I didn't find any. No tests to verify if this route had any function.

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Now this means one of two things:

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1- I did a poor job of searching (probable, since I'm not the best for searching these kind of things)

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2- There really is not much on the subject, meaning nothing to support either position other then layman logic.

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Actually if you fail to find research on a specific subject it probably means that there is nothing to research (or nothing felt worth researching). If there are no plausible functions for the route (as seems to be the case) there isn't much a researcher could do. You can't test a hypothesis until you have a hypothesis.

To answer your two points (just two of many misunderstandings).1) Evolution from fish to mammals involved some significant changes in body plan. To explain it simply, some blood vessels from in front of the nerve moved down the body while the structures that became the larynx remained where they were. This forced the nerve to grow longer, looping around the blood vessels. In short the anatomy all makes sense assuming evolution.2) Ortner's syndrome is a result of the recurrent laryngeal nerve passing close to the aorta. Heart problems can cause blood vessels to expand and compress the nerve, interfering with its function. In other words you have it backwards - this does not indicate that the nerve would be less healthy if the route were changed - it indicates that the route is a threat to the health of the nerve.

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Why? More conjecture?

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No conjecture, merely the obvious fact that a whole class of possible functions (i.e. those which require a nerve connection) are ruled out. Which doesn't exactly leave a lot of possibilities.

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Perhaps it is possible that animals are more attuned to listening for subtle sounds or frequencies generated by the larynx. Why? It involves communication. Humans may be more desensitized to these subtle sounds because of we have developed robust language.

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That on the other hand is pure conjecture. And not even a sensible one. There is no rational connection between it and the actual problem (and even if there were, the failure to cover humans is itself a serious problem since the nerve follows the same path in humans as it does in other mammals).

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That is your opinion PaulK. Why can't animals communciate or discern other emotional states from another animals of their own species? It could serve as warning signals for instance.

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Unfortunately your responses are becoming increasingly disconnected from reality. I never suggested that animals could not gain an advantage from communicating emotional states.The problem is making a rational connection between that and the route of the RLN.

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It is your opinion that it is a serious problem. My guess is that you don't want there to be some good reasons why the nerve is wired the way it is.

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So the fact that your "explanation" DOESN'T give a good reason for the route of the RLN in humans is NOT a problem to you ? Maybe you don't understand that that leaves you stuck with the human RLN as an example of poor design.And I am sure you can think of other reasons why people prefer to follow the evidence rather than believe whatever desperate excuses you happen to come up with. It is perfectly clear that it is the creationist side which is dominated by a choice of dogma over evidence in this discussion.

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However, the issue is to prove the second premise (the first being true)

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The Reccurent Laryngeal nerve has not been shown to be well designed
therefore it is a bad design
therefore a bad design exists in nature

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Which is, as I have said, an argument from ignorance.

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And it is NOT the argument in the OP.The OP points to a specific reason to infer bad design: Further discussion addressed the issue of whether the route of the nerve served some other function and the evidence indicates that it does not.(As an aside, Behe's argument is also misrepresented. Behe's argument is supposedly an "in principle' argument and the main problem is the underlying assumptions, not the logic of the argument.)

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I will finally add that holding on to that argument is anti-scientific. If you have already concluded that the RLN route has no function, you won't search for it. And if you don't search for it, you are unlikely to ever discover it if it does exist.

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Of course this argument essentially says that science must never come to any conclusions. Because if you come to a conclusion you will never reexamine it. This is doubly false. Firstly, if science never came to conclusions it would be useless. Secondly, the conclusions of science are always tentative and open to reexamination if the evidence warrants it.The fact is that the evidence strongly indicates that the route followed by the nerve has no function and that the more obvious route is a better design. This question can be reopened if more evidence comes to light but it would be foolish to assume that the route of the RLN does have a function and there appears to be no reasonable hope of productive research on the assumption that a function exists.Indeed, I must add that creationists often argue that we should conclude that abiogenesis is impossible even though the evidence is less solid (and more of an argument from ignorance) than in the case of the RLN. This is inconsistent with the view expressed above. (From a more scientific perspective there is a huge difference between shutting down a productive research program and spending time on research which has virtually no chance of finding anything).