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mmastrac
DamnInteresting
When I was a lad, I spent some time in front of a mirror trying to teach myself to move my eyebrows independently, like Spock. I eventually succeeded, but in the process I also learned how to move my ears. One downside is that these ear muscles began to involuntarily try to help. For instance, if I am looking down while wearing glasses, my ears contract to grip the glasses so they don't fall off, and after a while these seldom used muscles ache from the effort.
Galatians4_16
Keep at it, those ear muscles will be benching solid steel glasses in no time!
Remember; Pain is weakness leaving the body.
euroderf
It was only at the age of 50-something that I found out that my ability to move my eyebrows independently is not a general population thing. Amaze! Also FWIW I can wiggle both my ears, and independently too. Is there a way to make money from this ?
yapyap
There probably is a way to make money off this, but while doing so I’m thinking you also would be selling some dignity along with it.
Aachen
Huh, how is it not a general population thing? To raise an eyebrow is a common expression
Tool_of_Society
Yup I have the same issue with the aching muscles.
lilyball
I did the same thing as a teenager, I taught myself to waggle each eyebrow independently, but I never learned to move my ears. I didn't realize that was even a learnable skill.
m463
There was a movie where Jack Black does the wave with his eyebrows.
seek the wave, grasshopper.
RajT88
I wouldn't say I trained it, but I learned to control it.
I do find myself pricking up my ears to hear better, not always consciously.
FWIW, I can raise my eyebrows individually, flare my nostrils, twitch my nose, and also flex some muscle which pops my ears. Useless human tricks. Except popping my ears; super useful on airplanes.
saltcured
On the other end, I have the ability to voluntarily move my big toe away from the other toes in the horizontal plane of the foot. Like splaying toes, but just swinging the big toe sideways while the others are at rest.
But, I can only do this on my right foot. It's like I have awareness of a muscle and tendon there that is just absent on the other foot. It was weird to realize this asymmetry at first when I was young.
NitpickLawyer
> and also flex some muscle which pops my ears. Useless human tricks.
Also useful when you're diving. I can equalise without holding my nose for the first 10-15m, just by doing the thing with the ears. Doesn't work all the way down tho...
yabbs
The first 10m is the hardest. The last 10m is a cakewalk.
kstrauser
If you can’t will your ears to pop, here’s the manual way: https://en.wikipedia.org/wiki/Valsalva_maneuver
abdullahkhalids
The method involves closing the mouth and pinching the nose shut and trying to "exhale". As the wiki notes further down, this can cause damage to your hearing if you do it too forcefully, so use other methods first.
shkkmo
That's a way, and perhaps the most common, but far from the best. In particular, it has to be used preemptively before pressure builds up.
Alex-Programs
I have a lot of trouble on airplanes. How did you learn to do that?
RajT88
I don't know? I was really young, and as far as I can recall I just did it one day.
I always thought it was a muscle in my ears, but I remember looking it up, and it's actually farther back like behind your throat or something. I can't do just one ear at a time, it's all or nothing.
gpderetta
I can wiggle either ear independently. It greatly annoys my wife and my kids :D
doubled112
I've always been able to wiggle my ears, but just today I learned if I focus I can do one at a time. I'm 33. Thanks for the useless new skill!
iszomer
Me too but it annoys no one I know. Best use case is when I need more bass in my IEM's.
tim333
>weird reflex that when something startles me from behind
If you have cats and make a noise behind the ears automatically swivel back. I guess we must have something live that in our evolutionary past.
Gys
You trained it? I can wiggle each ear very visibly (and both). I hardly ever do but as I remember most people can’t. So i always assumed it was a DNA thing.
noelwelsh
Not the person you're replying to, but is also trained myself to do it. I basically touched the area where the muscle is, tried to activate it ... time passes ... and some unconscious process figured it out. Now, as a responsible parent, I use my super power to troll my kids.
ABS
I too trained it when I was in primary school after seeing a class mate do it.
And like OP I eventually managed to control one ear (right) but not the other, even to this day 40 years later
RajT88
I can twitch my left ear independently from my right. But not the right one independently. I'm sure it means something. Both at the same time is easy.
unsupp0rted
Same here, same ear
phkahler
>> I can wiggle each ear very visibly (and both). I hardly ever do but as I remember most people can’t. So i always assumed it was a DNA thing.
After reading the article I think its a "use it or lose it" thing where the muscles and ability to control them atrophy in our modern environment. We have more competing sounds and external means to "turn up the volume" so we can hear a particular thing.
justanotherjoe
It could be both
smusamashah
Someone recently told me that its genetic. Not everyone can control that muscle. I can, I learned it after seeing someone do it by lifting eye brows. I can control it without moving eyebrows now.
hinkley
There’s a couple actors that do this. Their character gets surprise or concerning news and their ears (and sometimes also their scalp) moves.
I find it very distracting personally.
jannyfer
I can’t control wiggling my ears, but I also have felt my ears perk up when listening to strange sounds. Sometimes accompanied by goosebumps and ASMR.
EvanAnderson
There's money here to whoever can capture the activation of these muscles to control prosthetic cat ears. At the rate I see them the prosthetic cat ear market must be double-digit billions.
Seriously, though, it makes me wonder if the activation of these muscles could be used in a hearing aid application. Why not add a couple rear-facing highly directional mics and use these muscles to control their gain?
teeray
There’s muscles in my ears that I have conscious control of that don’t really seem to do anything other than make a rumbling sound. They were fun to use when I was young playing, since I could make explosion sounds and get a realistic rumbling bass too. Are these the same muscles?
jrmg
Seems like not:
https://en.wikipedia.org/wiki/Tensor_tympani_muscle
I can do this too. The article mentions it being “rare”, but it sounds like it hasn’t really been studied so might actually be common. From casual discussion with friends in the past I suspect it’s more like 30-50% of people.
xg15
Same here and I always sort of assumed this was a normal thing of the human body. I'm kinda shocked to learn that many people can't do it.
What kind of muscle can switch between voluntary or involuntary depending on the person?
anotherevan
As the article mentions, the tensor tympani muscles are also involved in hyperacusis, which is an inability to tolerate sound at volumes most people have no issue with.
One of my kids has this. The best analogy I've found is it is like standing out in the sun when you already have sunburn.
fluoridation
Oh, so that's what that is? Crazy. Subjectively (besides the sound) it just felt like a vague pressure in my head, near the neck, so I never could figure out what the hell it was I was doing.
hinkley
I do this sometimes when my ears are congested and I’m trying not to do weird things with my jaw where people can see, to open up my Eustachian tubes. It works about a third of the time.
hyperbovine
I have this weird muscle in my ears I can flex to block out (or at least lessen) loud noises. I've never been able to explain it adequately to anyone, or find out what is going on, but it's absolutely real and not just, wait for it, .. in my head :-)
krisoft
That's absolutely real. It sounds like you are describing the Tensor tympani muscle. https://en.wikipedia.org/wiki/Tensor_tympani_muscle
In modern cars when the vehicle detects an impending collision it floods the cabin with pink noise to trigger a reflexive contraction of this muscle to protect the passenger's hearing from the even louder sounds of the collision and the airbags.
https://spectrum.ieee.org/pink-noise-says-prepare-for-impact
dguo
I can do the same and also didn't know how to explain it until I stumbled upon this subreddit: https://www.reddit.com/r/earrumblersassemble/
So apparently we can control our tensor tympani muscle: https://en.wikipedia.org/wiki/Tensor_tympani_muscle
fumar
If I do that, I hear a rumbling. I never used it to block out sound.
wkjagt
I can do the rumbling too. And a clicking too. I can even make someone else hear my ear clicking by having them press their ear to mine. I wonder if that's causes by the same thing.
NitpickLawyer
> And a clicking too.
You should get a check-up, when I heard clicking I had some wax accumulation.
Tor3
Same here, I hear a rumbling. I do occasionally use this to block or lower very loud (potentially hearing-damaging) sounds if there are no other means available.
hinkley
According to the Wikipedia article it may be involuntary.
mimentum
Same. Wonder how common this is.
albrewer
Sounds like you might have conscious control over your tensor tympani muscle[0].
gorlilla
I tried explaining this to my wife and she thought I was crazy. Turns out she was right, but not for this reason.
buildsjets
Most people may not use these muscles, but I do, to adjust the focus of my bifocals as needed. Zoom and enhance!
alexjm
That was how I learned to tense my ear muscles -- because I could see they made my glasses shift on my face.
mathieuh
Whenever I hear a noise behind me this muscle reflexively flexes quite hard, especially if it's a sudden noise that makes me jump.
lttlrck
Yes. It's quite a distinct part of my being startled by an unexpected sound, similar to hairs raising on the back on my neck.
kennyadam
Same. Is this something not everyone experiences or just never really comes up in conversation much I wonder?
dillz
Had to scroll surprisingly far to find this comment thread. My ears sometimes react the same way on unexpected noises in a silent environment. However, I can not move my ears voluntarily, none at all.
nusl
There's a lot of stuff that does something after we thought it didn't. I don't quite trust folk when they say "Oh, that's just there in your body but it doesn't do anything."
I get that some stuff genuinely doesn't because evolution deprecated it, but others we might not yet understand well enough to know this for sure.
AnthonBerg
My favorite – this is to some degree my interpretation though! – my favorite is the default mode network, a kind of constellation of brain activity.
It’s called the default mode network because they found it through magnetic resonance imaging or something like this, and this activity pattern was the first pattern they saw!… A-ha! This is the default mode network! The default! The default mode! Yes!… the activity pattern in the brain of a human who has been persuaded to go into a very tight-fitting tube and is there all alone and it’s not pleasant.
The default mode is activated during introspection and social isolation and among the things it does is generate the sensation of being something which is distinctly not part of the rest of the world.
alyandon
I'm not one to typically have strong fear/anxiety responses in situations that aren't actually dangerous. However, I felt extremely uncomfortable being partially inserted into an MRI tube for a lower body scan. I couldn't imagine being shoved head first into that thing without being heavily sedated or completely knocked out.
kstrauser
I had a head MRI and my main anxiety involved praying to any powers that be that my tooth crown was truly non magnetic.
frereubu
During my MSc I spent a total of more than 25 hours being scanned in an MRI machine for a study investigating the neurobiology of reading, and by the end of the study I was so relaxed in there that my main problem was not falling asleep because I was lying down with repetitive noises around me!
kedihacker
I feel uncomfortable around x-ray rooms. Can humans feel radiation or I am making it up?
PaulHoule
I don't really mind medical procedures like that. The time I got punched at Elephant Butte Lake and got stitches at the emergency room I went into a deeply relaxed state that scared the nurse because she thought I'd fallen asleep. Even the noise of an MRI machine is not that startling if you know it is coming.
ulbu
this is so interesting.
it’s not the first nor the last time wish that communities would not refrain from changing terminology. fitness is as important as accuracy and we shouldn’t be wary of dropping such inaccuracies, especially when they bring such strong connotations.
PaulHoule
For one thing the technology in an MRI based on a phenomenon known as nuclear magnetic resonance
https://en.wikipedia.org/wiki/Nuclear_magnetic_resonance
they dropped the "nuclear" bit because it is scary, it doesn't involve any ionizing radiation. It is all about making the nucleus wobble but not about splitting atoms. I have fond memories of doing NMR experiments in senior labs as a physics major.
EvanAnderson
On the theme: The phrase "junk" DNA always irritated me. I'm glad it is being replaced with "non-coding".
Anybody who has looked at a 4kb demo can intuit that "junk" code likely has a function, even if it isn't immediately obvious machine code for the host CPU. I'm no geneticist, and I understand cells aren't CPUs, but I've read enough to know there's at least a tenuous analogy to non-coding DNA and the kind of "junk" you might find reversing a 4kb demo that procedurally generates its output.
TeMPOraL
Yup, DNA turned out to not merely be a sequence of triplets telling a dumb matter printer which hard-coded proteins to make - at least according to what little I understand of evolutionary developmental biology[0], DNA is much more like procedural generation in gamedev or demoscene. That is, there's plenty of recipes for various structures and body parts, and then there's lots of DNA that's responsible for conditionally enabling or disabling or modulating those recipes, depending on more DNA that controls when and where and how much to enable them, and then more - a complex network of logic.
--
[0] - Didn't get much further than this four-minute intro to the field, but it is a good intro: https://youtu.be/ydqReeTV_vk.
(EDIT: It's actually the second part of a trio, that starts with a four-minute bottom-up overview of organic chemistry[1], and ends on a three-minute intro to nanotechnology[2]. I recommend the series together for how well it frames humans in relation to other life and universe as a whole.)
throwup238
There’s also epigenetics with mechanisms like histone modification and DNA methylation that can control expression without changing the DNA, but still being heritable.
725686
You might enjoy the book Junk DNA by Nessa Carey. Very interesting how complex and interrelated our DNA is. Pretty much spaghetti code.
phkahler
>> I don't quite trust folk when they say "Oh, that's just there in your body but it doesn't do anything."
If you expand that to "You don't need that" it covers the appendix, spleen, tonsils, wisdom teeth (even incisors can be removed to make room) and probably some other things. I'm in favor of keeping all your parts unless absolutely necessary, as all of these things seem to have at least marginal purpose.
kstrauser
I generally agree, but:
1. They used to yank everyone’s tonsils at any provocation. There was a swing back to trying never to take them. I wish my pediatrician would’ve had mine removed after my nth tonsillitis so I didn’t have to have them out in my 30s. That was fun.
2. Having had an emergency appendectomy, I’m sympathetic to the notion of proactively snipping them any time you happen to be in there anyway. Getting a hernia fixed? Oh hey, let’s grab the appy while we’re at it!
simianparrot
Except the appendix is an important organ. It has a high concentration of immune tissue and supports the immune system in the gut, and it's also a "safe house" for beneficial bacteria in the case of food poisoning or other gut "clearing" events.
It absolutely should not be just nipped out proactively.
pc86
I would expect at least some evolutionary pressure to get rid of unused things in your body. Let's just take the appendix as an example because it's probably the most common "you don't actually need this" thing that people know about.
Some appendixes burst. Sometimes this kills people. Sometimes this happens before that person has been able to reproduce. Wouldn't this cause selection for people who at the very least don't have bursting appendixes (appendices just sounds wrong to my inner narrator in this context), but also for people who have smaller ones. Over time this pressure would decrease but shouldn't it theoretically over many many generations result in smaller and smaller, eventually disappearing, appendixes?
sixo
Whether a thing can be selected-out depends on the shape of the fitness landscape in the environment.
For example, appendix-bursts are clearly rare enough and treatable-enough that they cannot be selected-out in modern humans. (But almost nothing can if almost everyone is able to reproduce, and any selection effects will be driven by the number of children which is largely cultural.)
If a thing hasn't been selected out, you can roughly conclude either that:
1. The selection pressure to do so isn't strong. Either few appendix bursts occur in an ancestral env, or they don't disrupt reproduction bc they happen later in life, or are treatable, or other causes of death kick in before the appendix matters.
2. Or, if the selection pressure is strong, there is "nowhere to go" in gene-space that improves this aspect of fitness, within the search-radius. (Which is really equivalent to 1: the selection pressure isn't strong enough to search widely enough)
3. Or there is a stronger selection pressure for it, even if you can't figure out what it is, like the "backup gut bacteria" thing for the appendix. (Which is actually equivalent to 1/2 also: the selection pressure isn't strong enough to find a way to separate the upside from the downside)
4gotunameagain
Can we be sure that we don't need the appendix ?
We used to think tonsils are optional as well, and there seem to have been some studies that find a link between tonsillectomy & Crohn's, Hodgkin's or even breast cancer (from wikipedia).
There surely must be vestigial parts in our organisms, like the one in the article, but more often than not we have no fucking clue how they interconnect with the whole and what their function is.
I think. I'm not a doctor or anything.
kjkjadksj
Appendix is being appreciated these days as a reservoir of good gut bacteria. So there’s actually probably some pressure to keep it around. Appendicitis is a thing but of course not everyone suffers it. Maybe in the primitive world you were more likely to see your skull meet a rock before that happened in significant numbers of people in the population to the point it affected offspring counts.
grog454
I would think so. Who says that's not happening now? It seems reasonable that evolutionary pressure can be strong enough to have a significant impact in 1-2 generations (for example due to the introduction of a new environmental threat) or weak enough to take thousands of generations.
evertedsphere
for me, appendix / appendixes (organ) / appendices (to a book) too, just like index / indexes (database) / indices
andrewl
Agreed. There is, or at least were, some parts of the body that were only recently discovered and not just known about and assumed to be inactive. It was only in 2015 that lymphatic vessels were discovered in the central nervous system:
https://www.nih.gov/news-events/nih-research-matters/lymphat...
That article is about mice, but they were later found in humans, too.
s_dev
The Chesterton's Fence of body parts.
Damogran6
Man, does THAT sum up the current political climate in America.
There exists in such a case a certain institution or law; let us say, for the sake of simplicity, a fence or gate erected across a road. The more modern type of reformer goes gaily up to it and says, "I don't see the use of this; let us clear it away." To which the more intelligent type of reformer will do well to answer: "If you don't see the use of it, I certainly won't let you clear it away. Go away and think. Then, when you can come back and tell me that you do see the use of it, I may allow you to destroy it."[97]
MrPatan
The Chesterton fence defense (yeah!) doesn't apply.
Did you care about Chesterton when the previous set of fence-smashers went around smashing (much older) fences?
ajb
A lot of this comes from the assumption that our organs each have a single purpose, so if the obvious purpose is not relevant in humans then the organ is useless. But most organs serve multiple purposes.
a_c
There is no grand design in biology. If something ain’t broke, evolution ain’t going to fix it. Retina in mammals facing backwards that gives rise to blind spot is one example. The laryngeal nerve that goes all the way down aorta and back up the neck is another
pfdietz
Also, if something truly serves no purpose, evolution will allow it to go away.
The classic example is the enzyme needed to make vitamin C. In our primate ancestors that lived on a diet rich in vitamin C, there was no penalty to losing this enzyme. Mutations that destroyed its function were not selected against. As a result, we now can't make vitamin C; the remnants of the gene for the enzyme have been so damaged that there's no path back to the working version.
Noumenon72
Informative X thread on how the recurrent laryngeal nerve path is dictated by having to develop embryos through chemotaxis: https://x.com/culpable_mink/status/1850937701518000383
He mentions that even if you're a giraffe, you have nerves just as long running to the end of your spine, and from your spint to the bottoms of your feet, so the extra length of nerve isn't really a problem.
a_c
There is a pathway for every possible configuration. It doesn’t dictate whether a configuration is optimal. Maybe the laryngeal nerve isn’t that bad. But that doesn’t guarantee all anatomy and physiology optimal
Iolaum
Not exactly. Everything in our body needs energy to maintain itself. It has to provide some value for the energy it consumes, otherwise not having it becomes an evolutionary advantage meaning evolution will gravitate towards it.
duskwuff
What a_c is getting at is that evolution can become trapped in local optima. The backwards retina in mammals is suboptimal, but it's locally optimal - the path from where we are to a better design (like the one in squid) is too long for evolution to hill-climb up to.
jjk166
Eh evolution will certainly try to fix things that ain't broke, indeed it will try to vary just about everything at some point or another. Bad cable management remains because no one survives the intermediate steps between functional configuration A and optimal configuration Z.
undefined
otikik
I ... thought this was common knowledge.
I learnt how to wiggle my ears when I got startled by a book falling from a shelf and my ears instinctively "raised". Picture a dog going from "idling" to "alert", with the ears pointing up. It was like that, but for humans.
I then said "Ooooh, so that's how you do it".
There has never been a doubt in my mind that the muscle is connected to "alert, listen closely".
tim333
There's a lot of odd stuff we're gradually figuring. Also interesting, some of the hair cells in the ear act as amplifiers and you can hook them up to an electrical sound signal and have them dance around:
I suspect the standard explanation for that as given under the youtube video:
> Since the amplitude, and hence the mechanical energy, of airborne sounds is tiny, the cochlea mechanically amplifies the incoming vibrations.
is wrong as it doesn't really make sense from an engineering point of view - if you've already detected the sound to activate the hair cell then that job's done. My theory is they actively damp down the large vibrations so you can pick up the small ones. There's a 10^5 amplitude difference between large and small.
TeMPOraL
> the cochlea mechanically amplifies the incoming vibrations
Is that even possible in principle? Amplifying requires adding energy, it has to be either provided from somewhere else or redistributed from other parts of the input.
EDIT:
Aha, but apparently this system is not a passive amplifier at all! Per Wikipedia[0], this is an active, electromechanical amplifier, which makes the explanation you quoted more reasonable (if not accurate).
--
[0] - https://en.wikipedia.org/wiki/Cochlear_amplifier but the core observation is also stated in summary here[1].
[1] - https://en.wikipedia.org/wiki/Organ_of_Corti#Cochlear_amplif...
philomath_mn
Idk man, survival seems like a pretty blunt selection force for such an intricate mechanism
blarg1
My ears tire when hearing foreign languages spoken, it feels like my ears keep automatically trying to discern each word as if I might understand them.
kennyadam
Stapedius-mediated phonemic saturation is almost unheard of by most people.
helge9210
Science around human body movements is in its infancy. Motion capture can't differentiable various muscle group activations, resulting in the same motion pattern. Electric activity sensors are not sensitive enough to capture individual muscle movements. And there are not enough interesting subjects (top athletes, performers etc) available to scientists to improve models and methods.
djtango
It's funny because these developments come at a time where a large proportion of the world no longer really uses their body for their living.
I wonder how different our ancestors perceived the world when their survival depended on their athleticism and keen senses. What knowledge and skills were common that have been lost to us now? There have been articles on HN about scientists "discovering" humans can exert control over their pupils and more and more scientists are "accepting" that echolocation in humans is real and learnable.
xg15
There are some fascinating stories about kids abducted and raised by wolves - who, when they were eventually found and brought back into human society, showed seemingly "superhuman" senses of hearing and smell. The senses became more normal the longer they spent time in human society however.
Not sure how credible those stories are, but if they are, this would indicate that human senses are a lot more flexible than we believe they are.
sriacha
One of my favorite examples is the possibility of humans to have magnetoreception.
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I trained myself to wiggle one ear as a kid and it's exactly like this. The muscle is much stronger in that ear and there's a weird reflex that when something startles me from behind, the same muscle that makes the ear wiggle triggers. It happens in the untrained ear as well.
Weird phenomenon.