Unintelligent design (recurrent laryngeal nerve)

No, and no. The route it takes makes it more vulnerable to injury.Your thought is "not even wrong".

I think it was a guy.But obviously no, seeing the vast majority of creationists pass and go, I usually feel bad for them with all their good intentions, but total lack of understanding of the subject. I feel like the odd man out with them (Cavediver did say I was too smart to be a creationist lol ...)

How is the old boat is an undesigned system ?Moreover, the Dysteological argument says that if the human eye would have been designed, then it would have been badly designed. Concluding therefore that it could not have been designed by an all-knowledgeable God.The counter-argument is that actually, is to say that, if it is a designed system, then it is actually very well designed. In other wors, both presuppose that it is in fact designed, and conclude opposite (the first to conclude that it cannot have been designed).So it is perfectly legitimate for me, in my counter-argument, to use an analogy using a designed system since this is the presupposition that is started with, and through the analogy show how actually it can be very well designed. The retina can detect a single photon, in other words, it has the optimal sensitivity. It also has a dynamic range of 10 billion to 1.I agree I exagerated a bit, and probably that given one specific particularity, we could outperform the eye. But of course, the strength of it is how it can perform at very high levels on every aspects all at the same time. Our machines can only deal perform in one aspect, and if it is ultra-sensitive for example, it cannot take on too much intensity or else it might as well blow up. I never wear sunglasses, do you think I'm going to end up blind ? Or maybe our grandfathers who didn't yet have eye filters all ended up blind as well ?A dysteological argument works based on bad-designed, not on being short of over-designed.Does God not exist because he didn't give us infra-red vision ? Or night vision ? Or in-built sunglasses ?Thiese are not dysteological arguments because they are not arguments of bad design, but of lack of over-design. You cannot use lack of over-design o negate the existence of a creator, since obviously you can find something that could have been added, etc.

I know very well that even if we do find a function the path the RLN takes, the ToE is not in danger of anything since as you said, the species could simply have taken advantage of the detour already there as to give it a function.But if we do find a function for this, then it renders the issue irrelevant to negate the existence of a creator. Because if it has a function, then an IDer would find this a satisfying answer as to why the said designer would have made it this way.This is in part why I am not very worried from these types of arguments, because I am aware that our knowledge of biology is far from complete, and that even though right now, it seems to serve no function, one may very well be found in the future. I think that you will find this legitimate on my part, as it is a very reasonable stance to take.On a final note, I noticed that everybody keeps talking how the ToE explains perfectly well this path by the RLN. I would be interested to here how it explains it. Thanks in advance!

It's not unlikely that you'll go blind, but it's very hard to believe you never wear sunglasses.WTF has this nonsense got to do with the recurrent laryngeal nerve, BTW?

I think the only time I wear sunglasses is when I play poker hehe. We get 2 months of simili-summer here in quebec, and 10 months of rain and snow.But to answer the second question. The RLN case is essentially settled, since as of today we have not found a function for the route it takes, I have no answer as to why any sort of ''designer'' would have done it this way. although, as I have repeated many times over, we have multiple examples of such situations in the past which permits me to hope that modern biology will find it a function. (Although some call this smokes and screens, I think it is a lgitimate and not very far-fetched hope on my part. Besides, I have never hidden that I didn't have an answer to this question)

Hi slevesque, Sure.The basic version is that the RLN is a branch of the vagus nerve, the fourth branch. Now trace our evolution back as far as fish and this branch took a path between the gill arches. This took it back behind the sixth gill arch. This is what we see in modern fish.Now in a fish this isn't a problem. The gill arches are close together and the nerve only covers a short distance - it all lines up, with each nerve branch going through each gill slit in turn. The problem is that in mammals, the "sixth gill arch" is homologous to and has evolved into the ductus arteriosus, a small channel that allows the blood in a developing foetus to bypass the lungs (this duct closes up soon after birth - usually). The RLN has to go around this. That's why it must take so torturous a route around the aortic arch. Here is a diagram showing the nerve in both fish and mammals (sorry it's a bit fuzzy); Now this makes sense from an evolutionary perspective. If the fourth vagus branch originally went around the far side of the sixth gill arch, then the modern RLN must do the same with regards to the ductus arteriosus. Why? Because one thing that evolution absolutely cannot do is evolve through a stage which, though might have a beneficial effect in a million years time, is lethal in the short term.For an engineer the problem is simple. The RLN doesn't need to go so far down into the chest. It's unnecessary and it exposes the nerve to a greater risk of injury (just ask any heart surgeon what they think of the of the RLN - the damn thing's in the way!). The obvious solution is to sever the nerve and re-attach it higher up, in the neck, where it needs to be, where it can be much shorter. It doesn't need to go around the ductus arteriosus; the duct serves no function in adults anyway. Problem solved. Here is an illustrative example; The obvious solution is for the gardener to walk around the tree and back round to the flowerbed from the other side.Evolution can't do that. Evolution works by mutation and a mutation that broke the nerve would kill the organism. There is no way for the RLN to evolve its way around to the other side of the ductus. (going back to our hapless gardener, it's as though the hose were attached at both ends, stuck around the tree) It's stuck back there, constrained by the limits of what evolution is able to do. So evolution does what it can. It stretches the nerve out, making it longer and longer (equivalent to our gardener lengthening the hose; a poor solution I hope you'll agree). This jury-rigged arrangement is typical of an evolutionary solution, doing what it can, modifying what it is given.That's what leads to a giraffe with an essential nerve that takes a pointless fifteen foot detour. No engineer would design something wit such an obvious flaw.For reference (and a much clearer picture of the above diagram) take a look at Evolution by Mark Ridley, the relevant portion of which can be found here.Mutate and Survive

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"A curious aspect of the theory of evolution is that everybody thinks he understands it." - Jacques Monod

Because systems, and parts of systems, have been added, replaced, repaired, partly removed, adapted to other purposes, and so on, over a long period of time. The work has been done by different people, with different goals and different abilities. Much of the maintenance done ends up being done in an ad hoc manner, often in the face of time sensitive needs (must cross the strait today, just make it work somehow). Not entirely sure what you are trying to say. Near as I can figure, you believe that if you assume your conclusion then a non-analogous analogy is a good thing??Perhaps I could have been clearer. The point of the boat metaphor is to demonstrate that just because something works, that does not mean it is an optimal design, or any kind of design at all. The old boat works, but no one would design it that way if they were starting from scratch. Similarly, the eye works. But it could have had a much more streamlined and trouble-free design, had it not had to evolve from existing, modifiable components.Like the RLN, the eye has an evolutionary history that makes sense of the compromises that are evident. A good design, OTOH, unconstrained by evolutionary history, would put the nerves in the back, skip the need for a blind spot entirely, and make a regenerative system that didn't require an opaque layer. Personally, I'd cover the receptors with a clear layer that served all their maintenance needs and also provided photosensitive variable opacity UV protection. And also I'd like something like a nictitating membrane. Have you ever heard of cataracts? UV exposure is one of several causative factors, and yes, they used to be a common cause of blindness.KP

This didn't strike me as quite right, as we know that cephalopods have eyes similar to vertebrate eyes, yet wired the other way around. Clearly, there must be an engineering solution to the problem.And, sure enough, there is. The analogous part of a squid's eye is located just below the photoreceptors, and is perfectly capable of providing sufficient nutrients and oxygen to these cells. They also appear to do so more efficiently than vetebrate eyes. In a vetebrate, the part of the cell directly facing the choroid is the photoreceptive cilia, not the main body of the cell itself, while in cephalopods this is the other way round. The energy producing reactions inside our cells are carried out by mitochondria, and so it is these, in the cell body, to which oxygen needs to be delivered. Vetebrate eyes not only have their light detectors facing away from the light, they have their engines facing away from most the fuel supply.As for the argument that the choroid is necessary as a heat sink, this doesn't appear to be true at all. The choroid is a source of heat. About a quarter of the light that falls on the retina is caught by light-absorbing pigments in the choroid, and then radiated out as heat energy. What we have here is a heat source placed directly next to the heat-sensitive part of the retina, which necessitates the high-speed blood flow through the choroid, so as to carry some of this heat away.This is mostly drawn from this article on the Panda's Thumb website.As a side note to Blzbub, it seems perfectly believable to me that slevesque never wears sunglasses. I never wear sunglasses, and I've never noticed this being particularly unusual. A quick straw poll of my flatmates reveals that only 50% (or two, depending on how you want to look at it) own a pair of shades.Edited by caffeine, : Added note to Blzbub

Hi Slevesque It's been a while since I heard the full explanation for this, so I hope I get this right! My understanding of the path taken by the RLN is that its route takes it around one or more arteries/organs. In fish, this nerve serves the gills. Fish don't have a neck, so the route around the equivalent arteries/organs is relatively direct. Mammals have a larynx, which I understand is ultimately an adaption of the gills of our ancestors. The RLN that connects the brain to the larynx is an adaptation of the same nerve that connected the brain to the gills of our ancestors. Mammals have evolved a neck, and the arteries/organs that the RLN goes around are in the chest of mammals. As mammals (or our intermediate ancestors) evolved the neck and chest, the selection pressures must have been that either the RLN goes down the neck and around the arteries and back up the neck, or the arteries go up the neck to the throat area, around the RLN and back down to the chest - or the arteries and RLN meet somewhere in between! (There has obviously never been a mutation that allows the RLN to unwind itself from these arteries - I suppose such a mutation is technically very unlikely to happen.) It is clear that natural selection favours taking the RLN on the long route via the chest. This seems intuitively to be the best option, as you obviously don't want arteries to be any longer or more exposed than necessary. I hope I got that more or less right. I'm open to being corrected by any biologists.I find one of the best way to picture these kind of adaptions is to imagine the development/evolution of an old city. Why do new roads and railway lines serving a city centre not always run straight? Because there are old buildings, older roads, natural topography, etc that all get in the way. A city usually develops as a series of compromises. A city that was designed completely from the beginning - AND WAS TO REMAIN FOREVER EXACTLY AS IT WAS DESIGNED - would be very different. I find it impossible to imagine a city that would never adapt in any way, though, and survive.As I say, there are very likely other smaller pressures that may have made small-scale tweaks to the routing of the RLN, but these would still ultimately be to do with the evolution of the body as a whole.The door is always open for other, better explanations. The ball's in your court.

Before you read my little post, I'd like to say there are a lot of rather brilliant people with scientific understanding that surpasses my own in varying subject matters(especially biological ones) on this board, which is why I've been reluctant to post anything in the past. Others could do better or what could I possibly add, so why should I post anything was my thoughts. Thus I fully expect people to attempt and perhaps succeed in tearing my argument to shreds, via valid, clear, and to-the-point reasoning, leaving it to whimper away defeated. I'm not a creationist in any sense of which I have heard it explained. I believe in evolution, albeit not in random mutations, but that organisms in some way control their own evolution, which is why, for instance, organisms within a species often co-evolve the same genetic traits as a response(at the same time usually) to an external pressure, which is why organisms can evolve the same genetic traits and it not be due to selective breeding pressures(inheritance theory). All that aside, here is maybe what a creationist might present as an argument for the recurrent laryngeal nerve.
-------------The fact that the laryngeal nerve descends into the aorta is why we are able to do pranayama (breathing techniques/breathe control) used in mediation and get the effects(mental stimulation and vocal training) that we do. It also stimulates our initial desire to speak as a child. The simple process of breathing makes us hear words inside our heads. It is simple circuit theory: connect all the pieces you need together to preform a particular function. It connects the breathing apparatus to the speaking circuit(vocal cords). Also it defines a natural resonance of the vocal cords, a base sound we make even when breathing. Basically this recurrent laryngeal nerve connects(and synchronizes) all the pieces together into one sensory and motor network/system that is necessary for the production of clear, articulate, and distinct human speech: breath flow control, vocal control, and mouth(includes tongue) control. Animals/fish/etc. have a direct route and thus no ability to communicate in any complex or meaningful way. To me, this could be as much an argument for evolution as it could be for creationism, though I prefer the evolutionary argument over any typical creationist stance.The whole wiring of the eyes and the blind spot: Before I heard about the rather unique wiring of the eyes I thought they were connected with our ability to see internally generated imagery. I read some time back(sorry no citation, it was a medical book though) that even with our eyes closed our visual cortex is 90% stimulated when we are seeing an image internally versus seeing the same image externally. Thus when I heard about the apparently indirect wiring of the eyes, I thought that this unique wiring was connected with our ability to see images internally with the fidelity, clarity and persistence that we do. Basically another way of saying this is that the odd wiring of the eye allows it to be stimulated internally(and externally), which after being stimulated is then sent to our visual cortex. It is what makes us human.Most computers have an external keyboard and mouse, laptops aside. These keyboard and mouse are connected to the computer via a rather long wire. In a sense that is a rather torturous and inefficient (think slow and energy costly) way of communicating between the computer and a human. Why would any intelligent creature design it that way? But it has proven quite effective for its intended use.

Hi JustNobody & Welcome In this particular case, I'll leave your theories to others to criticse. I'll just say that I think it's important that lay-persons such as you and I express our understanding of these matters in these discussions. That's really what this is all about. It's important for the experts (biologists in this case) to appreciate how much or how little the public understands of their theories, so they can develop their arguments and explanations accordingly. Don't be reluctant to articulate your understanding on these things.

Hi JN, welcome to the board. I hope you'll forgive me if I launch straight into your post; A hypothetical creationist? Not what you think? You know, it might be a better idea to argue from your own point of view for a while, rather than playing devil's advocate. Easy to claim, hard to prove. Do you have any evidence for this, by which I mean credible evidence, published by appropriate professionals in reputable journals and subject to peer review? You would need to demonstrate that your claim is true, that these benefits outweigh the risk of injury associated with the RLN and that any benefits demonstrated would disappear if the RLN was up in the neck.Basically, I'm saying that if you can't prove this, then as far as I am concerned, it's not true. Assuming that this is true, why must it go through the chest to do this? How can you show that this would not be possible in a laryngeal nerve that remained in the neck? I think you need to top up on your medication. This is nonsense. As far as I can tell, this sentence is meaningless. No it doesn't. The RLN connects the larynx to the brain and the brain to the larynx. Disagree? Evidence please... How would the laryngeal nerve be unable to do this if it were in the neck? Please be specific. Again, no it doesn't. It connects the brain to the larynx and the larynx to the brain. It has nothing to do with the tongue or breath control. Disagree? Evidence please... Utter nonsense. The route of the nerve is not the reason fish can't talk. Also, not all animals have a direct route for this nerve. Besides, many animals can communicate in complex and meaningful ways. I'm sorry, but the above is very far from being an argument for anything as it stands. There is simply too much nonsense, too little evidence. Is irrelevant to the topic of this thread, despite Slevesque's attempts to distract us by droning on about it. Wow. A) The long cords do serve a purpose. They allow you to move the mouse/keyboard away from the computer and control it at a greater distance. B) Unless you are suggesting that computers are not human inventions then yes, an intelligent being designed them. Obviously. I suggest that you take a look at the explanations that have already been presented for the RLN's detour and address those. At least then, you might be within a stone's throw of reality.Mutate and Survive

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"A curious aspect of the theory of evolution is that everybody thinks he understands it." - Jacques Monod

Are you unable to use google?https://www.youtube.com/watch?v=uW7NlkKaF38

''Are you unable to use google ?''This rhetoric question oculd be asked foralmost every single questio nthat is being asked here, because well, almost any answer can be found on the internet.Creation.com talks about the RLN, would you have prefered me to have told yo uright from the start ''Unable to use google?'' and linked you the articles ?I find it legitimate to ask if those who actually claim evolution explains the RLN to be, well, able to show that they do know. (And aren't just repeating the argument without knowing)