Nobody has said this. Everybody has explained, in varying degrees, that it is because your ear is a resonant cavity, and in any resonant cavity, octaves behave most similar to one another than any other interval. This is the same whether it is your ear canal, a clarinet, or the bathroom stall where you hum “Ave Maria”. If you absolutely insist on explaining it in evolutionary terms, it’s for the same reason that we don’t have pink antlers. It’s a non-trivial trait to evolve, and there’s no advantage in it (as of this writing), so it’s never happened.
I think we all know the relief when we think we hear exactly what we’ve made up our minds to believe.
Exactly. Damn straight. This is exactly what I’m saying. (Now that the OP has been answered by others.)
I am saying it turns out that the way we hear things is the result of an arrangement that is particularly efficient.
Evolution doesn’t always hit on the most efficient solution, but it tends to be reasonably efficient. And that is what explains the arrangement. It is (in this case more than) reasonably efficient. And the arrangement is what explains how we hear.
We could have had another arrangement. That would have been inefficient, but as we all know, evolution doesn’t always give us efficient solutions. (In fact, it enver gives optimally efficient solutions AFAIK.)
From what I could tell, most of your post was a result of not understanding that I understand and agree with all of the above.
Not that I “do” evolutionary biology, but I have no idea what it is you’re actually asking. Why did we evolve to hear certain frequencies? Why are we able to differentiate between musical tones? Why didn’t we evolve to hear things in a different manner?
Regardless of the actual question, though, it’s entirely possible that our current aural capabilities are evolutionary left-overs (plesiomorphies); our ancestors did it that way, and there have been no significant evolutionary pressures since then to change it. In which case, the current function would not be evolutionarily advantageous at all; it’s the result of some distant evolutionary pressures in creatures long extinct. In mammals, the evolution of the inner ear was associated with changes in the jaw structure (that’s pretty much the case for all terrestrial vertebrates, but the mammalian ear is among the more complex). So the way we hear things could well be a by-product of the evolutionary transition from the jaw-skull articulartion of early tetrapods to our current one. Yet again, not the product of active selection for any particular way of hearing.
Not everything in evolution happens because of direct selection pressures. Adaptationism is flawed, in my opinion, because natural selection is not the sole operating force driving evolution (primary, certainly, but not sole. Therefore, it cannot be the case that all extant features are the end result of selective pressures). You may well be seeking answers where there are none.
I’d need a better understanding of what, exactly, you are asking to give any better answer than that.
Oversimplification at best, straight up incorrect at worst. Natural selection works to both “cull the weak” and “promote the strong”. Selection is both creative and destructive. Indeed, the entire premise of natural selection is that those who possess advantages, no matter how minute, will have a statistically-significant greater chance of passing on whatever advantageous traits they possess (assuming such advantages are heritable) to the next generation. That’s how adaptation occurs; certain variations are selected for because they impart advantages to the individuals who possess them in a given environment. If NS simply acted to cull, then all variations which aren’t outright detrimental would have more-or-less equal probabilities of being passed on; the “average” would have just as much chance as the “strong”.
As I have pointed out, similarity in the environment does not have to translate to similarity in sensory phenomena. Two patches that emit exactly the same light frequecny in exactly the same light conditions can elicit entirely dfiferent color phenomena depending on the color patches surrounding them.
What Groman explained to me, and what others including Blake have confirmed, is that the way we do it is efficient. That is the info I was missing when I posted my OP. I now have that information.
I missed this the first time I read through your post. I’ll reread the article to see if I’ve misread it as you say.
What does it mean to have a common pitch quality if not to sound the same?
I mean, it seems like we can imagine a creature with an aural perception system just like ours, except that it is changed in whatever way you need to change it to produce the following effect: After all the sorting or whatever goes into making distinctions between frequencies, additional processes take place which remap these distinctions onto a new set of distinctions. Those that previously would have caused in the creature a “feeling” of “fifth-hood” will, after the remapping, "cause a “feeling” of “sameness” instead. And so on for all the infinite number of possible distinctions which are in fact able to make using the brains we actually have.
This would be a very strange way to do things, but its at least possible that such creatures could have evolved, isn’t it? Entirely improbable and implausible, but possible, correct?
In the case of color, you haven’t pointed out anything at all. This is an example of pattern interference at work. You can be assured that your brain “misses” thousands of octaves on a daily basis due to interference.
The real magic here you’re reaching for is the pattern-seeking part of the brain. It registers stimulation in the cochlea in intervals of 4, 8, 12, and perceives that a stimulation of 2, 4, 6, 8, 10, 12 is similar. Which mathematically they are, because one is a subset of the other, and physically they must be, because halves are the strongest natural resonance of a vibrating fluid column.
What you are still missing is that in this sense, hearing similarity in octaves is “efficient” in that it is “efficient” that we do not have pink antlers. Both are examples of how statements that are literally true can be contextually meaningless. You have confirmed the information you wanted to find while failing to grasp the context that would make it meaningful.
Yeah, you’re right, turns out that’s a bad example. I realized this a few minutes ago.
I still feel its clearly right that there’s no reason to think similarity amongst stimulators must result in similarites amongst sense phenomena. This seems obvious just as a logical point to me. But an example would be nice and I don’t have a good example on hand.
Yes, and this basically explains everything, and I basically get it.
But… that’s exactly what I meant.
I was under a misunderstanding in my OP which led me to think that pink antlers could be just as efficient as no antlers. Groman and others have explained to me why pink antlers are extremely inefficient. It turns out I had good reasons for thinking pink antlers would be just as efficient as no antlers, based on a particular reasonable misapprehension I was under about the physics of antlers. That misapprehension has been dispelled.
When I posted the OP, I did not know that octaves are objectively similar.
I now know that octaves are objectively similar in a way that other intervals are not.
In my opinion, this is most of the explanation as to why I hear octaves as similar. I do not think their objective similarity necessitates my hearing them as similar. But I do think it would tend very usually to cause organisms to hear them as similar.
I think we tend to hear things that are objectively similar as similar, not because of any logical point about a necessitation relation between objective and perceptual similarity, but rather, because it is generally best for us as organisms that we percieve objectively similar things as similar.
This is what I think, and this is what I take myself to have been saying all along.
Whatever you may think of whatever I’ve said before, do these statements seem right to you guys?
I just want to toss in here that, contrary to what one poster said above, it has always seemed to me that violet does indeed seem to be approaching a hue similar to red, nearly an “octave” below it in frequency. It makes me think that if our visual range extended over an octave, we would see ultra-red as similar to, but different from red, just as musical octaves sound similar to, but different from, each other.
This supports the view, as expressed by most posters here, that our senses evolved to reflect the world as it really is, and that the rare cases in which they fail to do so (optical illusions, etc.) have do to mostly with the physical limitations of the sensory apparatus. Those cases are not effective arguments for the notion that our perceptions are in some way psychological or sociological constructs that are unrelated to reality.
In other words, I don’t think it is possible that we could have evolved to hear fifths or other intervals as “the same.” I think we hear octaves as “the same” because they are, in a very physical sense, the same. That similarity is not merely an artifact of the brain working efficiently.
As many others have mentioned, the effect produced in a fluid column by a given tone is mathematically more like its adjacent octave than any other tone. Fifths are a little more dissimilar, and so on. That’s how I hear them, personally… octaves aren’t the same, but pretty damned similar, followed by fifths, followed by thirds, etc. Doubtless this is colored by my mathematical understanding of the topic.
The brain you are imagining must, for some reason, must conclude that sets which are mathematically more similar are in fact less similar. In other words, it would have to draw mathematical conclusions that are contrary to fact. I cannot envision any successful evolutionary strategy based on that sort of neurology. (insert joke about horrible musician or government accounting here). It might interest you to know that the hallucinogen DiPT is known for producing dramatic auditory distortions, shifting pitch and timbre. But I don’t know if it distorts the ability to perceive octaves. That would be an interesting experiment.
On preview I now see that you’ve come around… that you’re insisting it’s in an organism’s best interest to perceive the world as it actually is. Sure you can stand behind that statement?
No. You still have the cart before the horse. You still aren’t comprehending that this is an issue of physics, not evolution, not preference, not instinct. Physics, pure and simple. The physics dictates that some solutions will be more effiicent. The efficency of the solution does not dictate the physics. We have that arrangement to hear with because it is particularly efficient. If we had another less effeicient arrangement we would still hear essentially the same way because sound would still be a presure wave in a fluid medium. It woudl take more enrgy and itme to process the signal, but it would still sound essentially the same (qualia arguments aside).
No, physics is what explains what we hear. The arrangement is there to interpret the effect of physics on our bodies.
The current system doubtless isn’t perfectly efficient. But if we had another less efficient arrangement we would still hear octaves as the same because they fundamentally are the same, and we woud still distinguish fifths as different because they fundamentally are different. It woudl take more energy to process but we would still hear the same. I think this is the point you’re missing. If we process 200Hz in our ankle and 300 in our ear and 400 in our elbow we would still recognise that 200 and 400 are related because our anbkle would respond whenever 400 sounded. That relationship has nothing to do with biological structure or evolution, it is a result of physics.
No, you don’t agree. You just don’t understand as your latest cpmments have revealed. That is why I asked htose questions. so we could work out where your misunderstand.
Would you care to try to answer them? Particularly could you explain how an organism could evolve to distinguish frequency without some sort of resonating chamber? I think once you understand why that chamber is needed you will understand why it is all but impossible to evolve wihtout hearing octaves as related sounds.
While this is true you have yet to explain how it could not be the case for sound, or how any organisms could evolve otherwise.
Yes it is efficient, but what you seem to be missing is that even if we had another less efficient system we would still hear things essentially the same way, it would just use more energy, or result in greater signal loss. So long as we have sensors for 200Hz, 400 and 600 and a brain we can’t fail to notice that whenever we detect a 400 signal we also detect a 200 because 400 produces all the same peaks as 200. that forces our brian to see a relationship between octaves regardless of the way we do things. That relationship is real.
From the article: “all tones called A, regardless from which octave, have a common pitch quality, a so-called pitch chroma.”
Now let’s consider an example: An A sung by a soprano and an A sung by a baritone are both tones called A. According to the article they have the same pitch chroma. But if you are correct and they sound the same then you could simply dub in a baritone A for a soprano A into a melody and expect that nobody would notice. But that’s not true, even the tone deaf would notice. So quite clearly they don’t sound the same. That’s because pitch is defined by chroma and frequency. The vocal chords of a soprano vibrate faster and have a higher pitch than those of a baritone. The A tones they produce do not have the same frequency and the brain can easily spot them as different despite having a common pitch quality.
That is very different to your apparent belief that all tones called A sound the same regardless from which octave they come. Hopefully stopping to consider the notes from a baritone and a soprano, or a ukelele and a guitar, or a clarinet and a trombone will show you that all A note shaving the same pitch quality does not mean they actually sound the same. It just means they are perceived as being related. The brain is perfectly capable of spotting the difference and I;m surprised you thought otherwise.
How could we imagine that? Note that we both agree that we could evolve to intuitively grasp the relationships between fifths, but you are arguing that fifths would have the same pitch chroma (sound the same). How could that possibly happen without the brain deliberately ignoring the already present information that allows it to differentiate? Why would a creature’s brain evolve to deliberately ignore valid and useful signals that allow it to differentiate fifths? This is like saying we could imagine a creature that simply can’t see rectangles because its brain simply destroys the signal as it comes in before it can be consciously processed. We might be able to “imagine” such a ting, but not existing in the same world as a result of natural selection.
As I said in that post, this is what I’ve been saying all along.
To be clear, as I said in that post, I think it almost always is in an organism’s best interests to see the world as it really is. But it is not always, only almost always.
To answer your other question, we could imagine that the creature evolved in a world where there are birds of prey of various species, all of which emit a predatory cry that consists of a sine wave in a frequency related to the frequency of its co-speciate birds of prey by a ratio that is a multiple of 2/3s. But different species emit cries on different such sets of frequencies. And each species of birds of prey has a unique hunting strategy.
Then maybe creatures might evolve such as to hear all the cries of a particular bird species as “the same” in order to react to the correct strategy. One way to do this would be to have these creatures hear fifths as ‘the same’ in much the same way we hear octaves as ‘the same.’
If you want to point out that this might not be the best evolutionary strategy given other facts about the environment, I would resond by saying I’m just trying to come up with a highly artificial example in order to show how such improbable creatures might have evolved. Pretend these birds are the only thing around that succeeds in making a sound or something. Work out the engineering difficulties for yourself.
I’m imagining a counterfactual situation. Its easy enough to stipulate that in this counterfactual situation, it turns out there is no use to the lost information you mention, but there is a use to the perception of fifths as similar.
See my last post, addressed to Brain Wreck. Also, see my very recent very short clarifying post (#68) and see if you still think I’m off.
I htink you need to explain what you mean by “the same” here. You seem to be implying they culd here fifths as the same in the same way as we hear octaves as the same. But how could that happen? How could the brain evolve to ignore valid data that allows it to differentiate?
It could evolve to ignore it if there was no use in noticing it. I explained how it could be that there ends up being no use noticing it in the illustration I gave. (“Imagine these birds are the only thing that manage to make a sound or something…” is what I said. If that doesn’t satisfy you, just imagine that these birds’ cries simply turn out to be the only sound in the environment that is salient from the point of view of reproductive success. Can you not imagine how this could be the case in some physical possible (though of course highly implausible) system?)
Only in the same way that it’s easy to stipulate that an animal might think it’s blind even though it has perfectly functional eyes. This is pure fantasyland stuff. Simply saying there is no use to the lost information doesn’t explain how that could ever possibly be so. It even less explains why, just because there is no ise it would be covered up. The brain is obviously already capable of distinguish pitch, why not simply distinguish and analyse rather than jumping thorugh hoops to destroy information? How could that ever occur? What possible series of small steps could allow that to happen?
And I notice you still haven’t attmepted to answer my questions or adress the multiple other issues I raised, notably your misconception that “shared tonal chroma” does not mean “sounds the same”. At this stage I think we can probably conclude that you misunderstood eveything you have so far read in that article or this thread.
Yes, it is. All I’m arguing in this sub-conversation is that it is physically possible for creatures to evolve in order to percieve fifths as “the same” in the same way we percieve octaves as “the same.”
Remember, in my post number 68, I said I think that it is generally to the benifit of organisms that they see the world as it always is, but it is not necessarily always to their benifit.
One way I argue this is by noting that we obviously fail to make a lot of distinctions we could make in our environment. This is because seeing the world “as it is” in that way would be counter-productive.
Another way I argue this is by noting that it is physically possible that organisms could evolve to make judgments of similarity and difference very different than those we make.
If you don’t like the “fantasyland stuff” (though I’d like to see some elaboration as to why you think this particular thought experiment is a bad one for the present purposes) I can offer the following actual fact: We humans judge purple to be similar to red, but the light waves coming from purple surfaces and red surfaces are completely different: as different as visible wavelengths can be, in fact. So apparently in this case we do not see things “as they are.” So it is not implausible to think that this could have happened in other cases as well: for example, judgments of sameness in sound.
I think you misunderstood my phrase “sounds ‘the same’” to mean “sound identical.”
No, it still couldn’t. It first has to evolve to hear it. Then you require that it jumps thorugh hoops to actually ignore it rather than simply processing the pertinent input as well as the rest.
This is no different to proposing that polar bears will evolve an ability to ignore elephants because there is no use to them in seeing elephants. It’s nonsense. Organisms don’t evolve complex cerebral adpatations to filter out sensory input just because it isn’t useful. That can only iccur if the perception is actually harmful, and I can’t imagine of any situation where that could be the case.
If there is no use noticing something that is a neutral input. It isn’t reproductively detrimental. In your example there is no detriment in being able to distinguish those sounds, it is reproductively neutral. Why would organisms that can’t differntiate them because they have a evolved a complex system that filters them out have any posibble survival advantage? Both individuals can still detect birds of prey equally. The only difefrence is that one group needs to evolve a system that removes extraneous material to no good end.
No, it isn’t possible. Or at least you have been totally unbable to explain how it could be possible. It is only possible in the same way that polar bears might one day evolve to see elephants as ice bergs.
But what you apparently don’t understand is that we never, ever evolve complex adpatation to filter out valid distinctions just because we can’t use them. That is what your idea requires. It requires that polar bears evolve to not be able to see elephants.
So, say there are two sets of species of birds of prey. One set is the set I described. The other set is a set of “imitator” birds. What the imitator birds do is make a sound an octave higher than those made by its associated “original” bird. The imitator does this because it has a hunting strategy which is exactly right to catch a creature escaping from one of its associated “original” birds.
So our little shrews or whatever at first hear octaves as the same. Over the course of time, they evolve to hear fifths as “the same” in one “sense,” and octaves as “the same” in their original sense, in order to be able to avoid the original birds. Then, with the introduction of the “imitator” birds, it seems to me, the shrews might well evolve to ignore the “sameness” of octaves, failing to allow octaves’ “sameness” to register in their awareness. But they retain the new “fifth = same” way of hearing.
Again, suppose that for some reason, these birds are the only thing that makes a sound that is in any way important from an evolutionary standpoint. The shrews communicate by pheremones, say, and all they eat is moss, and they have no reason to avoid each other, and the birds make no sound when flying, and have gas bags so they never have to land.
Please do read post number 68 as I consider this line of conversation to be quite beside the point. In post 68 I try to distill what I take myself to have been saying, and to have taken away, from this thread. It’s very short.
