In this video, Richard Dawkins discusses the laryngeal nerve, which travels all the way down to the heart, loops around an artery, and then goes back up the larynx. It has to innervate both the heart and the larynx, but of course, if an engineer were to design this, he would have it innervate the larynx first, then go down to the heart. Not the other way around. It even does this in the very long neck of a giraffe, which means that we’re talking about twenty feet of unnecessary nerve length.
As Dr. Dawkins points out, the only imaginable reason for this “design” is that we evolved from fish, which have no neck, and so it doesn’t matter that the nerve loops around like that. I wonder what creationists would use as a talking point here? Would they pull out the old “God works in mysterious ways” canard, or perhaps the ever-popular “there must be a good reason”? How about “why would God act like a human engineer, when he is God?” (the last one is particularly amusing, because the assumption that he “designed” every species rather than letting them evolve implicitly assumes that he was acting like a human engineer).
Okay, I’ll bite. It’s a fair point, and honestly I don’t believe that Christians should shy away from intelligent discussion like this.
I’m trying to decide how to word this. If I say “the flaw in your argument is….”, then I come off like an arrogant jerk, which is particularly hypocritical given what I’m about to say. So instead, I’ll just simply offer a counterpoint, but please understand that I’m not trying to assert myself intellectually over you, or Dr. Dawkins, as if I were to have some type of higher understanding (I assure you, I don’t). Instead, I actually just want to respectfully contribute to conversation.
This argument rests on the assumption that Dr. Dawkins knows everything there is to possibly know about the laryngeal nerve, and even the human body itself. To make the definitive argument of “it shouldn’t be this way,” Dr. Dawkins is assuming that he is the definitive authority on the human body, at least equivalent to any god that could possibly exist. Basically, he’s saying “An all intelligent being would not have done it this way, because I wouldn’t have done it this way.” Because he cannot imagine a reason for this to be the way it is, it must not be so. He’s saying “I don’t understand God”, to which I would rationally reply “Well, yeah.”
I’m afraid you’re incorrect: the argument does not rest on the assumption that Dr. Dawkins knows everything about the laryngeal nerve. He does know at least one particular thing, which is that its layout is incredibly inefficient in mammals, even if it was fine in a fish.
I appreciate the sincerity of your effort, but at heart, it’s really just a repackaged version of the old “there must be a good reason” assumption. An assumption is not a quality response to the argument.
I see how you could look at it that way, certainly, and please understand that my goal is not to prove Dr. Dawkins as incorrect. My goal is also not to prove that it is, in fact, efficient (in which case, “there must be a good reason” would be a terrible response).
My goal is simply to remove the burden of proof (which I don’t believe belongs on either end). Instead, I simply feel that the argument of “This couldn’t have been designed by God because it seems inefficient to me” is not a sufficient argument to disprove God’s design, no matter how well learned the individual who makes the statement may be. By definition, it is only logical that we would be unable to understand God.
Would you at least be able to agree to that point? That is, that if God did exist, there would be no way that we could possibly understand all of His ways?
I understand what you’re trying to do, but “it seems inefficient to me” is a rhetorical attempt to downplay the argument. The arrangement undeniably is inefficient. The inefficiency of the layout is painfully, graphically obvious. To deny that is to literally deny something right in front of your eyes because you don’t like its ramifications.
The same is true of the backward-facing retina, the failure-prone nexus of breathing and swallowing passages in the neck, and other naturally evolved engineering disasters (such as the whale, which is a sea creature that can drown in water). What you have is a series of serious engineering mistakes that people can desperately try to produce excuses for, but for which we already have a straight-forward explanation at the ready: they were not engineered at all. They evolved.
Indeed, even if you could concoct explanations for it, we have such an astonishing variety of life on this planet; why would all mammals share this exact same trait? Surely at least one would deviate. But if we all inherited it, that would make sense.
What you’re saying is: “I want you to be open to the possibility that some explanation exists”. What I’m saying is “we already have an explanation staring us right in the face; why aren’t you open to that one, rather than rejecting it out of hand in favour of a mysterious alternative which you can’t explain, but which you hope exists?”
Which is more necessary for life, the heart or your vocal chords? It might be inefficent in an android, but given that it controls vital equipment, it makes a little more sense to have it go to the heart first.
Or maybe it’s just a quirk. That’s allowable.
Did you bother watching the video? The nerve length to the heart is the same regardless of whether it goes there first or last. The only difference is that the nerve length to the larynx is almost twice what it needs to be. You are doing what I predicted in the original post: assuming that there has to be a good reason and then trying to manufacture one.
This isn’t a great argument against creationism. You can’t assume that engineers always optimize for the simplest, most efficient and robust design. In reality (especially in the consumer electronics, and perhaps civil engineering) the design team has to continuously respond to changes in requirements, competitor product launches, unanticipated problems, or just plain bad design. Often we will follow a long circuitous path because we don’t want to change or re-qualify critical sections of the design, or because we are just plain out of time. Workable product today almost always beats perfect product four months late. That doesn’t mean we have a designer, just that we have better arguments for evolution.
Do you understand that in this case, there is a piece of legacy design which did make sense in an ancient model, but which is being kept in modern models for no reason? We’re not saying that “anything less than the ideal design means no designer”; we’re saying that we’ve identified a horrendous design feature which was obviously inherited from an older model, and which no one (much less an omniscient infallible divine designer) would ever design that way from the ground up.
You are right, but doesn’t the bible claim that god created fish, birds, animals and then man? Guess we have higher expectations of god than the Christians.
P.S. Many thanks for giving us SDN, the forum especially has been a wonderful place to frequent.
http://www.newscientist.com/article/mg20627594.000-optical-fibre-cells-transform-our-weird-retinas.html
Backwards facing retina improve vision, actually.
With the swallowing problem, if you made another hole that would come with distinct problems. Every hole a human has is a major site for infection. The cost of making a new large hole for breathing somewhere would be increased death from infections. Probably wouldn’t be worth it. Same for whales and gills. Gills are also metabolically costly, in that you have to pump water over them or swim constantly. Different animals are adapted for different niches and have different biology.
With the nerve, I know from my basic biology text books that there are several offshots from it that go into the heart and other things down there. The reason it coils round the heart is that it does nervey stuff to the heart.
It really annoys me as a biologist who believes in evolution when random scientists like Dawkins decide to say some feature of biology is poor because it doesn’t make sense to them. He does genetics. He has no more authority to judge the quality of design of nerves than I do to judge the health of a dog. Science is supposed to be multidisciplinary. No one knows everything. Including Dawkins. If nothing else, he should have checked out gray’s anatomy first. It’s in there.
“Look, somebody who thinks the way I do doesn’t think theology is a subject at all. So to me it is like someone saying they don’t believe in fairies and then being asked how they know if they haven’t studied fairy-ology.”
He’s a very arrogant man. He sees to regard neurology in the same way, since he didn’t actually think to consult one before making a wrong statement about neurology. You’re acting very much the same.
Point 1: that link of yours requires a subscription. Care to express the concept in your own words?
Point 2: no one is talking about a new hole. You already have separate holes for breathing and eating: they’re your “nostrils” and your “mouth”. Perhaps you’ve heard of them? The point is that the two passages start separately, then merge into one (just long enough to create a choking hazard), then separate again.
Point 3: Gills would be “costly” because you need to pass water over them constantly? What do you think dolphins and whales do all day? Why do you think fish use gills if they’re so terrible? What about the possibility of drowning and the need to periodically surface just to stay alive? Is that not “costly”?
Point 4: of course it “does nervey stuff to the heart”. What on Earth makes you think that anyone ever said otherwise? You’re still totally evading the point that it could go to the larynx first and then to the heart, instead of going the other way around.
Point 5: you say you’re a biologist, but you certainly don’t sound like a biologist. “nervey stuff to the heart”? Even if you are a biologist, your arguments seem pretty sloppy so far: much too sloppy for you to be lecturing anyone about the appearance of arrogance. You don’t even seem to understand the points being made at all, judging by your bizarre “holes” argument or your “nervey stuff to the heart” argument. People who are experts in a field generally use pretty precise language to describe concepts in that field, and demonstrate good grasp of the concepts when they’re attacking other peoples’ mistakes.
If your intention was to do this, you could have … oh, I don’t know … actually explained the neurology concepts you claim to be so familiar with, instead of saying “nervey stuff to the heart”, which does not at all inspire confidence in your (no doubt fantastic) superior grasp of the subject matter.
1. The Müller cells at the base of the eye at the blind spot reflect a greater proportion of the noisy light- that which has bounced around a lot. That means that the blind spot actually improves the precision of the image. They also serve as fiber optic plates, transmitting light with low distortion. So, the blind spot in the eye and the backwards evolution actually improves the image. Evolution took a problem that was fairly inevitable given the geometry of the blood supply and used it for a good purpose.
2. The mouth allows you to achieve greater oxygenation of blood during exercise than the nose, because it’s larger. This advantage likely outweighs the risk of choking. The choking hazard is deliberate. It’s one of our metabolic adaptions to enhance speed during exercise. You can’t stop choking without losing that advantage. I’d suspect that being able to achieve higher metabolic rates is much more evolutionarily favoured than stoppng choking. For a start, you need a high metabolism to have sex and pass on your genes.
3. Fish use gills because they’re adapted to one niche. They’re quite small, so they have a large surface area to volume. That makes it quite easy for them to get enough oxygen. Sharks, larger water breathers, have to pump water over their gills or move continuously (ram ventilation) to ensure adequate oxygenation of their blood. This is metabolically highly costly. Both approaches have their advantages and disadvantages. This comes from them evolving in different niches.
5. Of course, my answers are unsurported and carry no weight. My biologist title is a self applied title, as a biology student, and obviously poorly applied if it made you think I was claiming some professional degree, which I apologise for. Even if I did have a title, it would be meaningless outside my field of expertise, just as Dawkin’s is. If you wanted to get a true answer you should look to a whale specialist, or a vetinarian scientist who understands comparitive anatomy. There are obvious alternate explanations and Dawkin’s failure to consult serious scientists before making claims is a severe oversight.
4. Dawkins makes that mistake. He calls the nerve going down a detour. It’s down there to innervate various organs, not as a detour. His assistant claims it really only needed to go two inches. So, who on earth said it does anything different? He and his assistant did.
As to why, I’d imagine that it is something to do with foetal development. The nerve probably goes around the heart early in development and gets pulled down as the body develops. I couldn’t say with any certainty though. I’m not sure what nervey stuff it does to the heart, since gray’s anatomy doesn’t say. I could use biologically accurate terms, but they would just mask my ignorance.
You’d have to ask an expert on the subject. Neither you nor I have any authority to say that one particular route is the biologically optimal route, since neither of us know much about foetal development, and the trade offs and sacrifices the body makes during it.
Dawkins and you don’t know much about biology in a host of areas. You may have a basic grasp, but biology is so very complicated that you don’t know everything. As such, you do not know enough to claim that some feature in some animal is redundant with no scientific backing or independant experiments. A scientific theory should have multiple lines of evidence from expeirments. Logic is not sufficient, especially if you don’t know what experiments have been performed in the past.
1. It improves the precision of the image compared to what? An eye which is blocked but lacks the Muller cells? That would be a workaround to make the best of a bad situation, not an example of design. An engineer wouldn’t lay it out that way, and nobody would ever design a camera that way. Can you imagine someone designing a camera with a blockage between the lens and the CCD unit, and then using reflection and the blocked part of the CCD to collect extra information and saying it’s actually better than a conventional design that way? You might say “wait, this is biology, not engineering”, but that’s kind of the whole point, isn’t it? We’re talking about what’s wrong with the “intelligent design” theory which says that it is engineering.
2. True, the mouth is a bigger aperture than the nose. This is a much better argument than your “let’s not add an extra hole” argument from before. But again, it’s not an engineering solution. An engineer thinks about catastrophic failure and tries to avoid it, rather than considering it a minor issue, and would have probably just made sinus and nasal passages that can dilate more, if metabolic peak rate is an issue.
3. Just how much more metabolically costly is constant swimming compared to the use of (and growth and space and periodic surfacing activity required for) lungs? It seems that you’re just pointing out that nothing is free. Obviously, whales have carved out a niche for themselves, but again, it’s not something that an engineer would do. It would be like designing a car which can’t aspirate air, and needs to bring oxygen tanks with it. Again, you’ll say “wait, that’s engineering, not biology!” but that’s the whole problem of “intelligent design”; it puts biology in the realm of the engineer, by claiming that everything in biology was engineered.
4. Of course it goes down there to innervate organs. The question is: why does it not go to the larynx first and then the heart, instead of going the other way around? If it went the other way around, it could still innervate both the heart and the larynx. There is no advantage whatsoever conferred by the circuitous route. As you say, it makes sense with evolution, but no engineer would design it that way. That’s the whole point Dawkins is making.
You’re right that I’m not a biologist, but I’m not criticizing a biology theory. “Intelligent design” is not a biology theory; it’s an attempt to treat the entire ecosystem as an engineered system.
1. It improves the precision compared to an eye which lacks the blind spot. It is evolution, but it’s good evolution. Can I imagine a camera which had a blockage which improved the image? Yes I can. You are making a vague, qualitative argument about how god should design something. That’s not especially convincing to most, especially if it works.
A far more compelling argument is one where you have actual evidence that some adaption makes humans worse off. Like with appendicitis, probably the most commonly cited one. Since the backwards eye improves vision, according to new scientist, it’s not obviously flawed.
Also, another.
http://www.ncbi.nlm.nih.gov/pubmed/8986389
When the testes migrate down they leave a hole in the abdominal wall through which the intestines can sneak through. This wasn’t a problem for creatures which walked on all fours as gravity didn’t make their intestines fall in that way. It’s a problem for us. It can lead to intense pain and fertility loss. There’s also a simple solution. Make the lining thicker.
2. The reason I was suggesting an extra hole was because if you have just one hole you’d die within a few months. I currently have a bad cold. I can’t breathe through my nose. I’ve been hit hard in the nose in the distant past and had it clog up with blood. Under your design I would have died in my sleep a few days ago when my nose filled up with mucus to help expel dead infectious agents because I lacked a backup hole for respiration.
You can’t go without breathing for more than a minute or so, and the longer you go the less able you are to remove an obstruction. Having a second hole in case the first is obstructed is necessary.
3. Oh, I presumed you meant a whale should have both gills and lungs. Air is much richer in oxygen than water, especially when you go deep. You gain a substantial metabolic advantage from having lungs over gills. A whale will be able to swim faster and fight harder because of that.
4. That particular nerve is probably locked into it’s current path by foetal development pathways. But, as I note below, evolution found a way to directly innervate the larynx with a different nerve. Wikipedia suggests that it’s possible to independently injure either, and still retain some level of functionality. Hence the circuitous route likely has some advantage by evolution, as if the direct pathway is damaged it remains.
You’re not a biologist. You didn’t know about the direct larynx innervation. You’re not expected to. Dawkins didn’t either. He’s not expected to. It’s existence provides a perfect explanation for the route, and refutes the idea that evolution forces the nerve to take that route. Evolution could have directly innervated the larynx even more than it did. It didn’t, likely for a good reason.
Also, none of us are doctors who understand how nerves break. You reject the route on logic, but it’s perfectly possible that given the types of injuries people receive that the circuitous route is actually less prone to injury. There’s no way you could deduce that from logic. You’d need to be a specialist in the subject to know.
Again, you’re relying on the same flawed logic you used before: taking an obvious work-around and declaring that it’s not an example of an obvious work-around because … it works. Well of course it works; that’s why it’s a work-around. The Muller cells do work, but they’re still a solution to a problem. By the way, the Muller cells compensate for the indirect routing of light in the eye; this does not mean they actually make the indirect routing of light superior to direct routing. You say that the article states as much, but it is not the source paper, and the other articles I found on the subject say no such thing. You also say that you can imagine an engineered camera with a blockage between the lens and the CCD that outperforms a similarly engineered camera with no such blockage; I would love to see you actually back that up.
As for the backup innervation of the larynx that you mention, you still don’t seem to recognize that this has nothing to do with the point Dr. Dawkins is making. He’s pointing out that the primary nerve is laid out in an incredibly inefficient way. The existence of a backup does not refute this point at all. Can you honestly not see how “object A has an inefficient layout” is not refuted by “object B is a backup system for object A”? It’s a total red herring.
Similarly, your point about “extra holes” and sinus blockage only reminds us that the primary breathing entryway is too constrictive, probably because the “design’ relies too much upon the secondary one (and the resultant choking hazard). Your point about lungs vs gills and superior underwater performance is very interesting in light of your derisive comment about “qualitative” comparisons, since your own comments are entirely qualitative. In fact, if we look up a table of sea animal swimming speeds[1], we find that the fastest animals in the sea by far are fish with gills: the sailfish and swordfish clock in at 68 mph and 60 mph respectively, the bluefin tuna clocks in at 43.4 mph, and the fastest whale (the killer whale) clocks in at 34.5 mph. Perhaps, before declaring that “a whale will be able to swim faster and fight harder” and that I’m being too “qualitative”, you should have checked the numbers.
At the end, you fall back on the predictable old standby that I accused you of from the beginning: assuming that there has to be a good reason for that layout. After all this talk and all of these red-herrings you brought up, you did exactly what I predicted you would do. You looked at the unnecessarily circuitous layout of the laryngeal nerve, and assumed there’s probably a good reason for it.
PS. Your endless attacks on Dr. Dawkins’ qualifications to even discuss the matter are truly bizarre, since he is a qualified biologist, and despite the impression of expertise you’re trying to generate, you are not.
1. http://www.elasmo-research.org/education/topics/r_haulin%27_bass.htm
I did some research.
http://en.wikipedia.org/wiki/Internal_laryngeal_nerve
There is direct innervation of the larynx. He has to demonstrate that the indirect innervation is more prone to injury from most injury paths. Otherwise it looks like it’s a perfectly reasonable feature. Multiple pathways to the larynx so that even if one pathway is damaged another can continue controlling the larynx. I can perfectly easily imagine that cancer or injury could damage one but not the other.
This suggests that a simple way to disprove his theory would be to search the medical literature for an individual who received damage to the direct innervation, but not the indirect innervation, and who retained some level of function in the larynx. If one exists that shows that there is a distinct advantage to the indirect route. Wikipedia suggests that they exist, but doesn’t cite sources. Another way would be to look for sources which measure the relative ease to damage the direct and indirect route.
Thomas, it seems like you’re almost deliberately missing the point here. Dawkins is not saying that the recurrent nerve is useless; he’s saying that it could be laid out much more efficiently. Nothing you’ve said contradicts that. Instead, you seem to be thinking that he’s saying it’s totally unnecessary.
http://voxday.blogspot.com/2011/03/cost-of-post-christianity.html
That article is a laughably dishonest joke which attempts to turn “making mountains out of molehills” into an art form and political platform. More importantly, its Christian right-wing political message has absolutely nothing to do with the point about creationism which I’m making here, thus showing that you don’t understand the first thing about how to argue.
Here’s a hint for future reference: if you’re trying to refute an argument, your rebuttal should have something to do with the subject of the argument.
http://critical-thinkers.com/2011/03/critical-thinking-the-rational-discussion-flowchart/
That should help clear up any confusion. :-)
You’re referring to fact that muller cells have holes in them that mean that negate the disadvantages of a reflective area. I was referring to different research, that the nerve cells tend to prevent noisy light, light that has bounced around the eye several times, from reaching the detectors. This means it’s better to have them there than elsewhere.
The more important part is that they can’t go beneath the eye because the huge blood supply for the eye goes there. Mechanically, I can’t see a way to arrange the eye to avoid that problem and have the nerves facing forward. And indeed, squids, creatures with forward facing eyes, have substantially worse vision than humans.
“He’s pointing out that the primary nerve is laid out in an incredibly inefficient way. The existence of a backup does not refute this point at all. Can you honestly not see how “object A has an inefficient layout” is not refuted by “object B is a backup system for object A”? It’s a total red herring.”
You’re getting my argument wrong. I’m saying that object A may be a backup for system B. I.e. that the inefficient way could be safer, in terms of nerve damage, than the efficient way, or it could be safer given certain types of injury. You seem to be assuming that a shorter path is always better than a longer path. That is a vast generalization to make about all biology. You can’t just assume on logic that the shorter path is always better. You actually have to cite some evidence.
Having a small nose is good. It means that your nostrils can direct low speed (thus, mechanically less damaging) wet air (lungs don’t like being dry, cystic fibrosis is caused by dryness) to the lungs, and can reduce the amount of bacteria and large particles that reach the lungs. If you’re being chased by an angry bear that’s not so important, but it’s a perfectly good system for maintaining baseline metabolism.
Obviously, if you look at extremely small animals and look at extremely large animals there will be different physics and speeds. This relates to my argument vaguely, but it doesn’t really challenge it.
I’m offering alternate explanations for the phenomenon that you are noting. My explanations may or may not be correct, but they highlight an important point. You can’t just assume that biology is poor because it makes a good talking point against creationists. You actually have to test, say, the concentration of oxygen that a whale or a shark breaths in. You can’t be a roomchair biologist. Biology requires experimentation if you want to convince others that you’re right.
Let me get this straight: you argue that we can never say that an evolved system is inferior because we don’t know enough to say such things. Then you turn around and say that the cephalopod eye (which uses direct lighting) is … inferior. Apparently, you don’t even realize this contradiction (never mind the part about how you don’t bother explaining what this statement is even based on).
Then you say that the laryngeal nerve might be twice as long as it needs to be, in order to make it more resistant to injury. This is like saying that it’s harder to shoot a target which is twice as big: it literally makes absolutely zero sense. You say this because you’re desperately looking for some excuse to claim that it needs to be that long, and take that circuitous route, and you can’t think of anything else. Nor can you justify the red-herring of mentioning the other nerve, since that actually has nothing to do with your bizarre “twice as long, therefore more resistant to injury” argument.
Then you say that no living organism would ever want to reduce the number of pathways it can use to get air into the lungs, even at the cost of a potentially lethal choking hazard … but ignore the example of the whale: a massive creature with just one blow-hole (and this after stridently defending the whale as an example of superior performance).
And finally, you attack me for presuming to state conclusions on the matter without being a fully qualified biologist, even though you are not a fully qualified biologist either, Dr Dawkins is a qualified biologist, and you had to resort to looking things up in Wikipedia to make your points. Moreover, you never made the slightest effort to address my point that circuitous signal path routing is not some mystical issue that lies outside the knowledge base of an engineer. It is a simple physical layout issue; in-depth understanding of metabolic processes is not necessary to comprehend it, any more than a mechanical engineer would be incapable of doing a stress analysis on a femur.
I did some more research. Apparantly there is a small portion of the population with non recurrent nerves.
http://casereports.bmj.com/content/2009/bcr.10.2008.1107.full
“The non-recurrent inferior laryngeal nerve (NIRLN) is a rare anomaly (0.5–0.6% on the right side, extremely rare on the left side (0.004%)), which increases the risk of damage to the nerve during surgery.”
So, there is a mutational pathway to a direct route for that nerve. For some reason evolution hasn’t favoured it, in humans or giraffes. It’s been observed in patients so it’s presumably non fatal.
It’s apparantly slightly awkward since surgeons ocassionally dissect it, not realizing that it’s supposed to be there. I’m not sure what phenotype changes it gives in general life.
These mutations are extremely rare. They’ve surely appeared repeatedly in creatures since fish, creatures with neck, but some mechanism has prevented them from becoming common in the human populace or giraffes. You are essentially arguing that evolution has disfavoured a useful and better phenotype to the point where one variant only appears in 0.004% of cases.
No, I’m arguing that no engineer would have ever designed it that way, so it is really quite a devastating example against intelligent design. The fact that the metabolic gain from re-routing it is not sufficient to make it a natural selection issue is a complete red-herring to that point: a point which you apparently still do not comprehend after all this time.
I understand your point fully, I just disagree. You are arguing that it is poor engineering to reroute a system unnecessarily. I am arguing that it may actually be necessary to reroute the system. That the re-routed nerve may actually be more resilient to damage than the direct route for whatever reason.
Do you think it would be unreasonable for a creationist to say “I disagree, I think an engineer would design it that way because the recurrent route is better, and a good engineer designs a system to work well.”? Would you be able to cite any evidence to disprove them?
Do you disagree that in science, if you have a hypothesis, that you generally have to support it with scientific evidence? You are making a claim, that the rerouted nerve is worse or equal to the direct nerve. And also that this is proof of evolution, because an engineer wouldn’t make it that way. You need evidence to support those claims if you want it to be a devasting critique.
Earlier, I supposed that there may be foetal constraints to developing a non recurrent route. I was wrong. No matter how good logic is, a single fact can break any chain of logic. That, anyway, proved that there is no particular reason that evolution should have the nerve like that either. Some mutation can quite easily switch it round. To me it looks like an incredibly weak hypothesis.
You don’t have any evidence that the route is worse, and you don’t have any evidence that evolution would make the nerve recurrent.
So it “may actually be more resilient to damage than the direct route for whatever reason“, eh?
Do I really have to point out that you’re still doing exactly what I said you would do? Simply assuming that there’s got to be a good reason even if you can’t back that up or even hint at what it might be? Why the hell is a more circuitous route less prone to damage? If I inefficiently wire up a building so that I go back and forth over the same route repeatedly, how would this make me less prone to wiring problems? It should be make me more prone to wiring problems, not less.
You say I don’t have any evidence that either route is worse. I have plenty of evidence: the fact that it wastes material. You cannot dispute that except for your vague “for whatever reason” hand-waving. Your comments are increasingly bizarre: now you’re acting as if it’s a mere theory that the nerve is twice as long as it need to be, even though it’s a simple matter of geometry to observe that it is so. Do you understand the difference between a theory and an observation?
You say that a scientist needs a hypothesis; well there is a hypothesis for the observed inefficiency of the layout: a perfectly reasonable one, in which it is an inherited trait! You are the one who has failed to produce an alternate or better hypothesis, and “for whatever reason” certainly isn’t one. Again, you keep saying that you understand what I’m saying, but it’s clear that you don’t. Evolution neatly furnishes an explanation already, while you struggle to manufacture (presumably superior) explanations out of thin air or assume that such superior explanations must exist out there somewhere. That’s the whole point here.
When you have to use “for whatever reason” as your explanation, you’ve dropped into pure desperation territory. Frankly, you’re just being stubborn.
You said you would love to know how Creationists “answer” this. Frankly, I don’t see anything that merits an anwer. You found something in Creation you disagree with. What do you want, a cookie? I couldn’t help but notice that even some of your athiest friends, above, felt the need to point out somet things Dawkins either didn’t know or chose not to mention, suchas that the nerve in question also helps run the heart, and that Dawkins is not a neuro scientist and doesn’t know what he’s talking about. But even aside from all that, how are you proving anything except that you don’t know why the giraffe is designed that way (unsurprising)? It takes quite a bit of nerve to take one unanswered question (unanswered as far as you know) and claim that it disproves any reason behind the over-all design. I think it’s a pretty safe bet that God knows more than you and Dawkins about both neurology and molecular biology (Dawkin’s field).
You are probably going to peg this as another example of the “there must be a reason” response, but what you don’t seem to realize is that “There must be a reason” is a more-than-adequate answer to this sorry excuse for an argument. Dawkins didn’t have to sacrafice that poor giraffe to show me God didn’t consult him when He made it. I already knew that. :)
God didn’t make shit. It was clearly the Invisible Pink Unicorn. How dare any of you have the nerve to doubt the IPU in its infinite wisdom.
Also, the IPU created AIDS to strike down the non-believers. All y’all silly Christians will burn in Unicorn Hell for believing in the wrong un-falsifiable entity… Of course, it’s not so much burning, so much as being repeatedly impaled by Pink Unicorn horns, and it’s not so much hell as it is a nondescript room with off-pink walls, but yeah, you get the idea.
Seth, you’re obviously not thinking before writing (a common trait in religious apologists). The fact that the nerve also innervates the heart does not mean that it has to go to the heart first and the larynx second, instead of the other way around.
Imagine that you’re running some kind of token-ring signalling cable to the houses on a street. You would wire from house #3 to #5, then #7, then #9, etc, right? If someone wired from #3 to #9, then back to #5, then to #7, you’d say he’s an idiot. The fact that you need to get the signal to all those houses does not justify the ridiculous layout.
Also, if you have an actual neuroscientist who will say that Dawkins is full of crap, then please present him. I grow tired of people who are far less qualified than Dr. Dawkins (not to mention the associates he probably consulted with), bashing him for not being an expert in every single specialization of biology.
“Simply assuming that there’s got to be a good reason even if you can’t back that up or even hint at what it might be?”
I’m on holiday, away from the free access to scientific papers university brings me. All the proof I need is behind a pay gate. I could make up some possibility as I do below, but it’s as unscientific as making up something about the evolution of the nerve without doing any tests.
“Why the hell is a more circuitous route less prone to damage?”
It goes at the back of the neck, in the spinal groove. The direct one goes at the front, as the larynx is at the front. By going in the back way and coming in from below it may be less prone to injury. Plus, you’re saying it should take a diversion to go to the larynx. That diversion would take it away from the back of the throat to the front, and risk it losing heart functions. It has other functions. You can’t just assume that the larynx is the most important one.
Of course, I may be wrong. Or right. Hence the need for proof if you want someone to accept your conclusion. I’m not actually trying to prove this to you. I’m simply demonstrating that it sucks as an argument because when someone else asks for proof you can’t offer it to them.
“I have plenty of evidence: the fact that it wastes material.”
Minor issue. It doesn’t take much material. The issue of nerve damage is far more important.
“You say that a scientist needs a hypothesis; well there is a hypothesis for the observed inefficiency of the layout: a perfectly reasonable one, in which it is an inherited trait! ”
But, as it wastes material, and more importantly that increased length gives it more chance to break, why hasn’t evolution eliminated this maladaptive phenotype? We know it’s a single or a few mutations away. Dawkins didn’t know that some people have non recurrent nerves, that we have direct laryngeal nerves and so assumed based on his ignorance that the nerve had to be that way because it was that way in fish. There’s no reason evolution has to keep it this way.
“while you struggle to manufacture (presumably superior) explanations out of thin air or assume that such superior explanations must exist out there somewhere. ”
Your idea, that synthesis of the nerve was metabolically expensive enough to matter is probably wrong. It’s a fairly small nerve and making it isn’t likely to increase metabolic demand much over the routine and random demands of exercise.
The problem of nerve damage is more serious as that could reduce your ability to function. The longer a nerve is the more prone it is to damage. Of course, different routes have different susceptibilities to damage, so it’s necessary to test how susceptible to damage they are before you conclude that one route is worse. An engineer wouldn’t design a system to fail more often.
From a scientific perspective, it’s good to assume there’s a function to biological systems. If you assume there are none you may miss out on the functions. If you assume there are functions then you can test for them, and whether you’re right or wrong then you know more about biology. Positive theories are easier to test than negative ones.
“When you have to use “for whatever reason” as your explanation, you’ve dropped into pure desperation territory. Frankly, you’re just being stubborn.”
From my perspective it’s pretty frustrating too. You’re making a claim about biology, with no support or backing of any sort from scientific papers and seemingly expecting others to do the leg work to prove or disprove your theory.
It also really, really helps if you can show that the adaption hurts humans because the idea of god hurting humans is emotionally painful. Anything that hits at the emotions is especially devastating as an argument.
Spinal groove. Spiral groove was what I was thinking of, but it’s actually the tracheoesophageal groove. Somewhere at the back, anyway.
Thomas, you haven’t told us why the nerve needs to loop. why did allah, um god, do that?
Holy Quran (the last testament) doesn’t deny the theory of evolution. In fact, there are multiple verse in the holy book that hints to their of evolution which can only be comprehended by the knowledgeable people. But what seems to non-intelligent design is because of our lack of full understanding of the full function of human body. Don’t forget that science keeps updating itself and it is a process of knowledge accumulation. A small hint: The holy Quran in many verses hints to a relationship between the heart and to what we utter!!
I’m a little confused…and I did skim the comments (they were redundant), so I apologize if my question seems out of place (but I would appreciate a polite response). Aren’t there several creations that have unnecessary features? Think about about our gadgets and even works of art. Sometimes as the consumer or viewer or whatever, we don’t always see the point of what we think is unnecessary. We do a lot of unnecessary things, like eating dessert! I’m not trying to suggest that this nerve situation is similar to enjoying peach cobbler, but there are a lot of things that are unnecessary like, texting (in a lot situations it’s like just pick up the phone!), superstitions (lucky clothing), having a favorite color or food or a favorite anything, wearing perfume or cologne, rudeness, being 6’8 (i’m not and i wouldn’t want to be) and many, many other things.
My point being, who cares that it’s not efficient, who cares that its unnecessary?! Why does it matter? Why does it matter what God did or did not design? This seems silly, like this conversation is unnecessary. But, unnecessary things still have merit and value and they can be interesting and fun.
**This is a friendly reminder for a polite response; no condescending language or sarcasm or anything like that please =)
Um, isn’t God supposed to be infallible, unlike us humans with our love for unnecessary things like art and neat technological gadgets?
No, I still stick with my equally unfalsifiable claim that the (imperfect) invisible Pink Unicorn did it.
since when does being unnecessary equal fallible? i don’t think just because things are unnecessary means that God is infallible
No, but with a design that is so blatantly inefficient, it’s fairly obvious that if there is a god, he is an inept engineer. I prefer my creation story of a time-traveling Dorothy Gale absconding with Batman and traveling into the far past, where the end result was the Big Bang.
Ok, so we agree that if God does exist, he’s an idiot and/or sadistic? Good, we’re making progress then.
What evidence do you have for God that I don’t have for my Invisible Pink Unicorn?
well, I for one definitely believe in the Invisible Pink Unicorn. Because, you know, there’s nothing disproving that lol.
I love how when you ask a creationist to prove god exists, they can’t offer solid concrete evidence that is nondisputable. Not that evolution is perfect, but at least there are solid theories that match and have evidence proving them. Creationists have yet to do this, and all their ‘proof’ they provide has a logical explanation, they just refuse to see it. Narrow-mindedness is not attractive.
To Jordan: We’re not. Its the creationists who are arguing that God make humans because of the eye, makes bombardier beatles, bacteria because of their pump……. and on and on. So, if God design is so perfect that it couldn’t be created by evolution, what happens when we see perfect examples that it isn’t so perfect?
To Thomas: Here’s a question. Why not just… split the innervation? Have two seperate nerves? Or three nerves for each if you want to? That would be a even better “engineered” reason.
The argument is that evolution has no “foresight”, it can’t predict things. It can only work things post hoc, hence, the recurrent largyneal nerve is a perfect example of this because it was a work-around done POST HOC to solve the immediate needs.
Interesting post and discussion. Here’s my 2 cents. I realized I’m a few months behind, but I just discovered your blog, and this is the most recent post.
Background: I am a neuro-radiologist (physician). I am a Christian. I believe God created everything. I don’t exclude the possibility that God used evolution as a means of creation, though I’m undecided on whether in fact He did. There is a lot of evidence for evolution but also a lot of things about evolution that don’t makes sense … complex organ systems for which an evolutionary pathway seems farfetched or inexplicable.
All that to say this: No argument for evolution is an argument against the existence of God. I don’t know why Dr. Dawkins insists on linking the two.
Regarding the topic at hand: There are 45 miles of nerves in the human body. Are you really suggesting that a design that added another foot or two (or even 20 feet in the giraffe) is “incredibly ineffecient” or that the designer is an “idiot”? I would say that if one could show even the possibility of a small benefit of this design, it would make the negliglble cost of a few extra feet of axon length worthwhile in the design.
And here’s one: Perhaps the late division of the vagus nerve and long course of the recurrent laryngeal nerve, which causes its fibers to run in proximity to multiple different organ structures and systems, actually makes it MORE vulnerable to injury (as opposed to making it less vulnerable as Thomas proposed, though I believe that is a fair theory and don’t know why Mike is so hard-headed in discounting it). And since its end-organ (the larynx) is one whose dysfunction (hoarseness) is plainly obvious even with the most minor injury, perhaps the circuitous course of the nerve serves as an alarm or early warning system for other organs. As a neuro-radiologist, I have seen tumors of the skullbase and carotid sheath, jugular chain and tracheoesophageal groove lymphadenopathy/tumor, and aneurysms of the aortic arch present with hoarseness as the earliest and only symptom, allowing treatment of these conditions before they become incurable or fatal (metastatic cancer, aortic rupture).
All good (designed) systems have built-in error checks and failsafe mechanisms, and these always require extra resources, but the benefit outweighs the cost. I am simply shocked that Dr. Dawkins would propose that because a nerve is “too long” that it represents poor design. There are so many complexities to even human-designed systems, let alone the human body, that to point to one feature and make such a broad statement as Dr. Dawkins makes is plainly asinine. But that is Dr. Dawkins’ way – to make shocking statements without real scientific rigor in hopes to draw in a crowd (note the awed looks on the faces in the audience).
Several problems would arise if the recurrent laryngeal nerve (RLN) travelled directly to the larynx.
To begin with the fibres connecting to the larynx would be in a much more exposed position, instead of sitting in relative safety in the groove between the trachea and oesophagus. This is potentially serious, because damage to these nerve fibres would mean that adduction of the vocal cords would be unopposed. This would lead to acute airway obstruction requiring an emergency tracheostomy.
Secondly, if the RLN should take the shortest route to the larynx, it should also presumably take the shortest route to the other organs it serves. It should therefore give off its fibres to the inferior pharyngeal constrictor muscle, the trachea and the oesophagus before it reaches the heart. This would expose these nervous connections to greater danger for the reasons given above. Furthermore, it would mean that the RLN was at its finest and weakest in the section leading to the heart. This would clearly enhance the risk of those connections being damaged.
Finally, the design suggested by Dawkins would eliminate the loops that the RLN takes around the aorta and the subclavian artery. Whilst these may seem to be unnecessary, they act rather like the cable hooks in ceiling light fitments, reducing the strain on the nerve end connections, and hence limiting the risk of damage to those nerve endings from accidents or sudden neck movements.
I couldn’t bring myself to read all the back and forth.
What I think is this – God (any god of any religion) decides in it’s infinite wisdom that belief must come from the soul and goes on to create billions of reasons NOT to believe.
The poor bastards that wrote all of the books couldn’t comprehend that so they made up stories and pushed strange ceremony type stuff until they were satisfied that they had something that no other religion had. And then later they all declared that if those weird things were not done on a certain arbitrary schedule then you would go to a very bad place for all of eternity. Unless of course you either paid a lot of money or killed innocent people. Then everything would be cool.
If this is caused by evolution, then why has it not worked it’s way out of the giraffe due to it’s useless nature? Also, there is also the creationist argument that we are not in the world we were meant to live in, and we are not as we were meant to be due to the whole Garden of Eden ordeal. Working on that basis, everything is already flawed and does not reflect it’s original purpose or design.
You obviously don’t understand how evolution works. It can’t go back and reverse things. That’s the whole point; an intelligent designer COULD reverse an ancient fork in the road, but evolution can’t.
You obviously don’t understand how creationism works. Same situation, different boat. Could is not the same as should or would. Yes, an intelligent designer could reverse it, but why should they? It’s already broken and in the creationist thought, the intelligent designer is timeless. What right would a person have to demand he fix what we broke immediately? You’re making the assumption that everything must be done now in our time to justify it to us.
Ah yes, the infamous “I’m rubber you’re glue” debate tactic. Too bad it doesn’t apply at all in this case; creationism does not “work” at all, since it has no working mechanism. So I can say that you don’t understand how evolution works (since you clearly don’t, and you didn’t bother responding to the way I took apart your misrepresentation of it), but you can’t say that I don’t understand how creationism “works” because creationism has no working mechanism at all. You literally apply to its LACK of definition as the basis of your argument.
In fact, that’s the whole point of creationism: it has no mechanism, and no possibility of rational comprehension, and we are supposed to just accept it on “faith” despite these glaring shortcomings. You confuse a narrative with an explanation, and you are seemingly incapable of understanding the difference.
Also, this question doesn’t make sense which I will explain, so don’t shoot me at this point. It’s a fantastic discussion question, but we’re working with two completely different topics. One, is an idea that revolves around the world as is, the other has to do with a topic that requires faith. It requires a person to have faith in some things that they can’t answer, and a belief that there is a higher being who they cannot physically show you. It’s like telling a blind man that the phone he is holding is black and arguing about where the black paint came from.
Your analogy is flawed. Faith doesn’t give you special sight while others remain blind; faith makes you blind. Faith is the refusal to apply a particular faculty (specifically, critical thinking), which is a form of intellectual blindness. It does not give you any extra insight; it tells you to stop using an insight you already have.
What I was trying to say is that the idea of faith is like speaking in a different language. The terms of both sides are very different, and that makes them hard to compare. Your complete disregard for another option is blinding for you. It isn’t a refusal to apply critical thought in any way. What right do you have to say that your critical thought is truth? As imperfect people, and I can safely assume you cannot say people are perfect, therefore it’s pretty likely we’re going to be producing flawed “critical thought” as well. Your disregard of any other way of thought blinds you from faith as well. In order to have faith in the way of creationism though, one must use their own existing insight to follow through on it or it wouldn’t be faith. You’re assuming that what you call faith is the absolute definition. Mindless ignorance is not faith, it is in fact mindless ignorance.
You don’t understand what critical thought is. It is the willingness to subject ideas to tests. Evolution has been subjected to many tests. Creationism has been subjected to none. It is even defined in such a way that it cannot be tested.
Defining your ideas in such a way that they can’t be tested is a conceit that goes beyond mere ignorance, and ventures into the realm of intellectual cowardice and dishonesty. You attack me for “disregarding” your ideas, but you make no effort whatsoever to address the reasons I give for disregarding those ideas.
Mr. Wong, you, Sir, are in fact a very ignorant guy. Your thesis always have to be the truth, others are rubbish for you. Intruding, that a man, who’s such interested in arguementation isn’t able to credit good arguments against his own. Instead you react hostile and arrogant.
Forgive him father, he don’t know, what he does. _\\//