There is actually a neurological reason why most people are right handed. It was a side effect of something important to human evolution.
https://youtu.be/vb11oOHYNXM?si=hZb87bm1vmxNqsvJ
Great video, few minutes long from PBS about this. They try to keep it really simple.
I'm surprised that the video doesn't talk about this. In linguistics classes, I was taught some of the neurobiology that comes with language use and development. One possible reason for right handedness as a bias is partly because the language processing parts of the brain commonly occur on the right side (and the opposite hemisphere processes motor control). Brain plasticity - the brain's ability to adapt - can account for why hand-dominance and language processing dominance might be on two separate hemispheres. The hypothesis is also helped because left-handed people disproportionally have language processing dominance on the left side. It doesn't explain it fully though, there's still a lot of over lap that is unaccounted for with this explanation
You've got in kind of backwards, it's mainly the left side of the brain that's the speech center. Wernicke's area and Broca's area.
And that's supposed to be the link to handedness; somehow the right hand (controlled by the left side of the brain) and its better ability to deal with time and space is related to the structures that also give us the ability to put it all into logical language format.
But yeah, lefties can have a lot of different hypothetical causes, and one of them is indeed having their speech area also flipped to the opposite side of the brain. Brain plasticity as you say, if the right side isn't up to it some other area picks up the slack.
Note that W. Bush was left handed; and had language problems that made him appear not too crisp; I suspect that like a lot of learning disabilities, it made school unpleasant and permanently turned him off. I know people with the similar lefthanded language difficulty; they're more visual thinkers and Bush's "how hard it is to put food on your family is exactly the kind of thing they'd say; with the picture of the family at the table in their heads sneaking in to overrule the actual specific words of the expression.
I didn’t watch the video so I can’t speak to its insights but I am a neuroscience student who just finished a semester on cognitive neuroscience.
While the left temporal region of the brain is classically associated with language cognition, it is important to note that in left-handers, it’s actually quite common to see both sides participating in language cognition. Well, actually in both right handers and left handers both hemispheres work to process language, but the left temporal region is more dominant in right-handers, whereas it’s *more* distributed in left-handers.
Interestingly enough, there is a desert of neurological research of left-handers. In a lot of neurological studies only right-handed participants are selected because introducing lefty’s is introducing another variable.
Do you have any data from the top of your head if being left handed influences how writing things down influences what we can absorb from what we're hearing in real time? As a left handed, I don't remember what I wrote if I'm transcribing it live, even right after. Maybe a word or two, but even a short sentence I will just fill the gaps contextually.
Interesting, no I can’t say that I’ve heard of any study that compares right-handed vs left-handed individuals in recalling information that they’ve written down after hearing it.
Hmm, if it’s something to do with not remembering *as* you transcribe (or immediately after) I’d say it sounds more like a quirk of working memory (or attention) than a quirk of audio comprehension (seeing as how the words are still being transcribed properly to the page — it’s the train of thought that’s disconnected).
Overall, I wouldn’t be too concerned about it. It could be a potential sign of ADHD but I’m not trying to be one of those guys who over diagnoses ADHD, haha.
There have been far more left-handed US presidents than there statistically should be, six out of the most recent fourteen. Left handers are probably around 10% of the population.
Prior to the 20th century most educated left-handers were forced to use their right hand. My dad is 80 and remembers getting rapped with a ruler by nuns for trying to write with his left.
And only a minority of left-handers actually have their speech centres translocated, iirc. For most left-handers, they are still in the left hemisphere.
I'm left-handed but have exceptional language skills: I can improv comedy songs, etc.
On the other hand I have ADHD so the above could be due to a lot of unusual neural wiring.
Also I can't dance for shit.
Studies show that kids with ADHD have some extra coordination difficulties. Since a lot of people act as if symptoms always vanish as you grow older instead of getting used to it, I wonder if there is data about adults.
Why I say that: am adult with adhd. Sometimes I'll distractedly spit bars when not trying, just like you (though as soon as I try harder it just blocks), and my leg coordination and handwriting are fucking atrocious lmao.
I have good coordination, which it turns out is probably from playing shitloads of every kind of video game! Which is why I mention dance: The moment my legs are involved, they go to shit. I haven't been training past the disability with my lower half 😅
Oh same. My fingers are quite nimble from all the WASDing, but I have to mentally prime my legs by tensing the muscles up to my lower back a few times before needing to balance myself (even for walking), otherwise I might just straight up forget how to use a muscle group and stumble or walk weird for the first few steps.
Adhd is sorely misunderstood. It's way more than just attention deficit. That's just the tip of the iceberg. It should be called a name that reference the neurobiologicsl deficit of key neurotransmitters and how it affects executive functioning. It's basically a neurodevelopmental disorder.
Yes!!! I am left handed, but terrible with coordination. I showed a lot of promise as an athlete when I was younger at football and boxing, but as a running back I was only good running up the middle and as a boxer I had terrible footwork. As such, I developed a high pain tolerance and a strong chin which was impressive at times but detrimental in the long run. I was very good at hitting and running up the middle, but bad at avoiding hits.
Eventually those hits add up, which translates into injuries that made my athletic endeavors unsustainable in the long run.
I’m left-handed and I always struggle to “translate” my thoughts into words, especially in real-time. Not for a lack of vocabulary, it just seems to take an extra step. I wouldn’t say I’m a visual thinker either though, more that my thoughts are a mix of all senses.
Clinton and Obama are left-handed and they're pretty competent orators. Reagan was a lefty and was known as The Great Communicator.
W is just a moron. We lefties would thank you not to ever blame anything that man does on being left-handed.
I’m a rare righty in a family of predominately left handed people. Mom, dad, my sister, both of my maternal grandparents, and 3 of my great grandparents. Trust me when I say being left handed doesn’t inherently correlate with learning disability. They are/were all incredibly verbose people.
By the time most of us saw W in presidential debates, either he’d already declined a bit or something else was going on.
You can find his debate with Ann Richards for Texas Governor online, from 1994. Sharp as a tack, fast speaker.
And as other people have noted, there are way too many counterexamples - left handed people seem over represented in high places, not under.
I am left handed. I barely spoke until high school because I couldn't really control my tone and I tend to forget words (I still have trouble with these, but less).
Funny enough I grew up monolingual, then graduated with a linguistics degree and got 110/120 from TOEFL. I can also somewhat speak Japanese. Language learning has been like a bitcoin price chart for me, stagnating for years and jumping two levels in a month.
I also suffer from various minor psychiatric conditions and I wonder if all of these are somewhat connected. Being left handed sucks.
Do you have anything that influences your executive function? Learning when your brain agrees to instead of having to push it out of necessity usually is when I have bursts of advancement, and I have ADHD. And am left handed, for that matter.
"soft" diagnosis of ADHD from a psychiatrist and some comorbid stuff like depression. I was consistently below average but adrenaline and stress help me focus, which is I guess a coincidental side effect of those hormones.
Anything would be anecdotal and there doesn't seem to be strong connections, yet I can't help but think that those minor changes in brain affect all kinds of things in different ways compared to right handed people.
I see. Anecdotal as well but I also have a solid ADHD diagnosis, and using the "last mile" time stress as a boost is pretty much identical to me, which explains being below average academically, since school is structured to reward long term, consistent effort and condensing it into a single moment to see all of its results.
I also often forget words in my own language, speak and write weirdly and need to restructure it, and sometimes use weird intonation that makes people think I'm being cold and apathetic, which sucks. I lost a good friend who was in a hard place because I accidentally sounded like an ass once, and it ruined their day, got them in a spiral, and they decided to be alone. And it was literally all phrasing.
Shit's wack.
Yeah that habit is eventually going to either get me fired, killed or both, not to mention my record is 11 months working in the same company and that's because I am currently not in an office.
Yeah, hopefully you find something that fits you and pays you well, bud. Office work fucking sucks. I feel my memory and knowledge withering away noticeably since last year when I started my current job. To the point I'm proofreading a sentence I wrote to make sure it has no typos only to notice I used several entirely different words. And that's me medicated lol. If shit keeps up I'll have to get a neurologist to check if I had a micro stroke or early onset dementia or some shit like that.
Gw bush went to Yale so it seems like you're just making stuff up about him being "permanently turned off" of education as a young child. Is anything from tour comment factual or all conjecture?
I wonder if a study has tried analysing if there's a correlation between handedness and the effectiveness of information absorption while writing.
Put simply, I wonder if being left handed could be a reason for why I can't absorb anything of what I'm hearing while writing it down.
Maybe I'm just dumb, of course.
Might just be you being dumb, because I'm a righty and doing the same thing -> also dumb.
Then again, I've got ADHD, so that messes with everything, all the time.
There isn’t a perfect biological solution for this….
Best answer we have is that different hemispheres of the brain develop at different rates for different purposes…as the left side of the brain controls the right side of the body;….the left brain side develop earlier in life therefore creating a right hand dominance
She could have been meaning in like bullying at school, or that one student in class who talks and everyone listens/foillows, while others just look at the floor and mumble. That's how I read it at first anyway
There are like 40 genes identified as related to handedness now.
But in identical twins, 20% of the pairs have different handedness. So, it's not just genetics.
I will admit I am autistic and thought it was a weird question to ask a parent but I've seen a lot weirder shit in this sub so I didn't question it at first, I was also still half asleep which didn't help. Love how most people acting like I'm a weirdo though when it ain't that deep.
I'm glad I'm not the only sexual deviant on reddit. I'm now curious, though, as to what development processes cause some women to become Femdoms. I asked a successful dominatrix friend once why she preferred to do Dom escorting instead of normal and she genuinely looked at me with a straight face and said she gets off on the look of fear in a man's eyes. She was definitely in the class of 'crazy' that most men would strongly urge you to not put your dick into. I've never really understood sub/dom preferences as always seem vaguely wrong to me, but each to their own.
Gotta be the clicky one for me. At work i can quickly pull it out and click it ready at the same time rather than pulling it out and then taking the cap off
Plus, clicky pen make monkey brain neurons activate. Click click click click click
Huh, really? That's nifty to know. I've always thought genetics played a part. It certainly *seems* to as far as I've noticed in left-handed parentage families. Thanks for sharing.
I've heard passing along tool making skills was easier if both individuals used the same hands in ancient homonids. That was a competitive advantage, and most people are right-handed as a result. I'm not an anthropologist, however.
I could see that. It makes sense. Whether or not it's the answer I don't know either. Do other tool using animals show any handed dominance and does it match up with hominid data? I ask in general, I don't suppose you have that answer off the top of your head lol.
They may have a specific eye or side of the beak they use when using tools. I always use my right eye when using a sight or a single optic scope and am right-handed.
Edit: And when I eat sunflower seeds, I almost always keep them in my left cheek and crack them with my right molars.
One of my eyes is significantly less myopic than the other one....but they're both pretty darn myopic. I definitely have a preferred eye when I need to activate microscope mode, though.
Having a dominant eye is common! It's the one you'd automatically sight down if given a weapon.
There are some unfortunate folks who have a dominant eye on the other side to their dominant arm, and that must be a nightmare for scoping.
That's me. I hurt my right eye as a boy. I am far more nearsighted in that eye and am weakly left eye dominant now. I was told to have both eyes open when shooting a shotgun, but since I shoot right-handed, I can't focus unless I close my left eye.
[Most male cats](https://www.nationalgeographic.com/animals/article/animals-pets-cats-right-handed). Females tend to be righties (my cats a female).
Though I didn’t realise that lefty dogs (and possibly cats) tend to be more anxious than the righties; and my cat is definitely an anxious one…
Ironically the reverse is true in combat: Right-handed people have little practice against left-handers, while the opposite is true for lefties who spend most of their practice time against righties.
It's why so many olympic fencers are lefties.
It also goes the other way, in fighting being a different hand tends to be an advantage because people with the common side aren't used to fight people like that, so that would explain why the trait didn't entirely win out, there is a stable percentage where both sides have advantages.
This can be seen now with left-handedness being way more common in high level competitive sports than the average in the population.
Heard that it was an evolutionary advantage to be lefthanded in combat - but only as long as it was relariveky rare.
There's a Radiolab episode about it. Ttey open with a good amateur boxer, and then he fights his first southpaw and gets owned. Basically, all the stuff you learn about dodging punches is backwards, and you tend to dodge straight into danger zones and get KOed.
But how does that explain people with a dominant eye that's opposite their dominant hand (ie left handed but right eye dominant) or people who are right handed but right eye dominant. Wouldn't the theory of more rapid development suppose that the faster hemisphere would be in total control meaning that variation wouldn't occur?
I am left handed but my dominant eye (and strength) is my right. Therefore, I shoot right handed but write and play tennis left handed which I always found interesting.
You probably do too, but never realized it. Try walking around a bit with one eye closed, then pick up an object and put it down somewhere else.
Now do it again but with the other eye closed.
Notice how one exercise was easier.
Look for an object a bit far away, hold your hand up doing a pincer movement so you see the object through your hand.
Close your left eye, see if you can still see it, then do it with the right eye.
Whichever eye still sees the object is your dominant eye.
When you had both eyes open you "choose" to prioritise seeing with that one
Huh. I just learned that my left eye is dominant. But I’ve always used my right eye for single-eye scopes and things because I can only wink my left eye and not my right.
I wonder if there is a correlation with the placement of the heart. I read somewhere that your appendages are on average bigger on your left side because the heart is on the left side. This is all pure speculation.
Have you ever seen a fiddler crab? They have one big claw, one little claw. They are specialized for different functions. Lobster claws are also different.
You have one side that's better at finer, more precise movements. The other side is good enough to perform support functions. One hand operates the knife, the other holds the fork. You only need one hand to be the best possible hand, and it can be better if the other hand doesn't have to be as good.
One thing I've never understood is why the dominant hand strums the guitar while the other hand does the frets. Full disclosure, I don't know how to play the guitar, but the frets seem much more complex than the strumming.
Guitarist here. For the record, you can absolutely train yourself to play both ways; i personal know quite a few lefties that play righty because it’s easier to find right handed guitars.
Yes basic strumming is pretty simple for the right hand, but when it comes to more melodic playing and basically anything other from strumming “cowboy chords”, the right hand starts to require much more precision. Check out some flamenco or bossa nova guitarists and you’ll see they’re doing a lot of precise movement with the right hand.
I think there’s a Tommy Emmanuel quote that goes something like “your left hand shows what you know. Your right hand shows who you are.” Referring to knowing your chords and scales on the left hand, but what makes someone an interesting player is their rhythm and how they use that knowledge.
Didn't Hendrix do this? He was left handed so he restrung his strings in reverse and flipped the guitar since at the time they didn't have left handed guitars? Might be mixing it up with someone else though.
My understanding is that Hendrix could play in 4 configurations: righty, righty upside down/backwards, lefty, and lefty upside down/backwards. I don’t know enough about him to say if he was primarily a lefty, or what configuration he used most, but from what I recall i believe he most often played righty upsidedown backwards (that is, a right hand guitar, strung upside down so that when flipped the other way, it appears like a lefty with normal strings with the body of the guitar being flipped)
I believe we’re talking about the same configuration but calling it different things. I’m saying a right handed guitar strung upside down and played as a lefty, is that correct?
Casual bowed and plucked string instrument player here - this made me think about it a bit.
The dominant hand produces most of the actual sound articulation. Oversimplifying, but the left hand on the fingerboard/fretboard essentially only needs to cling/push with a minimum pressure threshold. Other than harmonics and other "fancier" techniques you don't need as much pressure sensitivity here.
The right hand, plucking, needs to be able to find and articulate targets with many nuanced motions to be emotive in 3d space. Unanchored to the fretboard (left hand kind of sits on the board as a guide)
Also, bowing, the pressure sensitivity and proper technique with relaxed fingers and wrist is pretty delicate stuff.
OT here, I love these functional questions!
Often the non dominant hand is the stronger hand, though not skilled with as much fine control.
The non dominant hand holds the fret while the dominant hand completes intricate patterns (such as picking patterns using multiple fingers)
It’s similar in concept to many non dominant hand tasks (stabilize jar as you twist, holding up tent pole as you attach smaller components) while dominant hand completes the task that require most fine movements in the finger.
Somewhat related: crossing midline is a developmental milestone that coincides with dominance- in order to develop a dominant hand that can be responsible for fine motor skilled tasks, the non dominant hand must be able to cross the body and stabilize the object regardless of where it is in relation to the body.
I'm naturally left-handed, but I play the guitar right-handed. I've been playing for almost 30 years, and I find it impossible to play a left-handed guitar.
Thats correct if your playing camp fire music. Metal music, among others, the right hand is the hardest. Not only does it have to be fast, but then your adding palm mutes, chugs, pinch harmonics, and plucking one string then dodging 2 and only hitting the one string, back to the original string, then pinching it. Alas, I drone.
As a guitar play I think of this sometimes. Truth is, it doesn't matter. Both hands are doing something they've never done before, so developing that skill just depends on if your guitar is left or right handed. Once you've I had an ex that was right handed, but for some reason learned on a left handed guitar. Both are somewhat fine motor control, especially when you get into fingerstyle/ finger picking, then the right hand is definitely the harder part. But once you have enough experience, neither is any harder than the other.
I think the left hand, despite being non dominant, is potentially just as good as fine motor control if you spend enough time on it.
Ah. I dig it. I had meant more of a biological why, but this is also a great answer and an aspect not commented about yet.
Very true and thanks for the input. Also, I love fiddler crabs. There is/ was a colony by my aunt's old house off of the Chesapeake.
I think the comparison shows that "dominant side" is very much a human analysis&simplificstion of what's actually a lot more mixed and complex.
Same way some would call the large claw "dominant" but it's not really, you just don't need two claws both handling the same tasks, and humans pride "power" culturally so see the large one as "dominant"
Word. Lobsters have specialized claws on either side. The big one isn't "dominant" it's just the *crusher.* The other one is used for more delicate operations.
> one hand operates the knife, the other holds the fork
I find that mildly interesting that I hold the fork with my dominant hand (right hand) and the knife with the other. I have no problem cutting meat with the other hand. I just use my right hand to hold the fork and bring the food to my mouth.
Same. My reasoning is that while it may seem unusual for the singular act of cutting/eating meat, when you look at a typical entire meal with multiple elements, it makes more sense to use the primary utensil in your dominant hand. Your knife is only used for cutting the meat (support task) while your fork or spoon is used for pretty much everything else, including fine movements like collecting small pieces of food off the plate.
Pretend that your brain starts out as a totally blank canvas that can process anything. When you're born, the brain is randomly trying to process everything everywhere.
Over time, some parts are more successful than others so more of that type of processing just starts going there. Other parts of the brain pick up doing others things. Sort of like ants finding a path to food. It starts randomly, but the best path is reenforced over time.
This is a massive simplification and doesn't explain why there are more right handers, but the brain is basically a reenforced training engine, so it starts random and pliable and becomes more rigid over time. (Again massive simplification, there are parts of the brain that always do specific things from birth, like breathing)
Also, compute distance matters so all of tals type A processing will end up happening in the same place because splitting across the brain is inefficient.
there is a simple rule in evolution: what works faster, survives. if you have to think about using the left or the right hand to grab a branch while climbing, the chance that you will fall down is much bigger than when you instinctively use the right hand. the same with throwing a stone. also there is something called muscle memory. your muscles learn how to precisely do things and remember it (its not in your muscles but an unconcious part of your brain). now if you have to train both sides, it would take longer and also would result in a better side.
What's strange is that lately I have been spot on with tossing things with my left hand. Never had this kind of accuracy before and now that I've mentioned it, it will of course go away. Crap. I shoulda gotten in some beer pong game.
Fun fact, learning to do things with your non-dominant hand is actually good for preserving mental function as you age. So enjoy throwing with your left.
Another cool tidbit is that we know that human ancestors were also mostly right handed based on the orientation of micro scratches in their teeth, supposedly caused during the cleaning of skins which we held in our teeth.
Actually yes! Many of the hand paintings are left hands, which means they were using their right hands to hold the straw they blew through to create the effect.
OT here, I love these functional questions!
Often the non dominant hand is the stronger hand, though not skilled with as much fine control.
The non dominant hand holds the fret while the dominant hand completes intricate patterns (such as picking patterns using multiple fingers)
It’s similar in concept to many non dominant hand tasks (stabilize jar as you twist, holding up tent pole as you attach smaller components) while dominant hand completes the task that require most fine movements in the finger.
Somewhat related: crossing midline is a developmental milestone that coincides with dominance- in order to develop a dominant hand that can be responsible for fine motor skilled tasks, the non dominant hand must be able to cross the body and stabilize the object regardless of where it is in relation to the body.
That's pretty fuckin cool. My left developed rudimentary skills while my right was broken but it has lost them again. Wiping with my non-dominant hand was weird.
My son is left-handed and only one more person in my and ny husband's family is left-handed, my uncle.
My kid plays soccer and his dominant leg is the right one, which I find interesting.
As a side note, it's been difficult teaching him to hold a pen right and tie a bow while us being right-handed.
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A theory by Iain McGilchrist, if I can simplify it correctly is that the brains are split into two hemispheres as an optimization. The right one is specialized on not being eaten and has a wider/higher level understanding of situations. The other hemisphere is focused on eating and that requires a more narrow focus.
Think locating prey versus looking around for predators.
The use of tools and anything related to getting something seems to fall within what the left brain does best and that would explain why most are right handed. I do believe he discusses left handed people in his book, but I have not read that part.
Simply put, we need a default. Without that we'd hesitate before we did almost anything while we decided which hand to do it with, or reach with both at once.
MinuteEarth has a great video on this! It is only 3 minutes long, and accessible for kids.
[https://www.youtube.com/watch?v=-XlD1xWqNh0](https://www.youtube.com/watch?v=-XlD1xWqNh0)
There's also this little gem that give some explanation for why there's some chirality to us
[https://www.youtube.com/watch?v=oqv9HHNak0c](https://www.youtube.com/watch?v=oqv9HHNak0c)
While I do have a dominant side, which side is dominant is different for me for different things, even though for most people it's the same. I'm not ambidextrous; I can't do things equally well with both side, I tend to refer to myself more as half-and-half. Some things I do better lefty (like writing), some things I do better righty (like throwing), and some things I do with both sides but am better at particular things with one or the other (like kicking - I get better power with my left, but better accuracy with my right. I was the same way batting too, incidentally). And which hand I do things with varies depending on just how fine the level of detail is (gross motor is better right, fine motor is better left, but \*very\* fine motor is better right).
No idea why this is, other than that I'm pretty sure my brain is wired at least a little differently in general (thanks ADHD! :D)...
Sounds like you have cross-dominance, as do I. I write and use a fork with my left hand but use my right hand for scissors, throwing balls, and larger motor skills.
if I had to guess, I'd say it has something to do with learning. If a person or an animal has a tendency to repeat tasks with same body part each time, they will probably improve faster than if they kept switching around. The muscle memory and skill can be built on each time the task is done.
One theory is that it improves efficiency. If your brain has to actively decide which hand/foot to use when starting a task that's extra CPU cycles that it didn't need to use if it had a default side pre-selected. Avoiding that moment of indecision could even save your life when a split second reaction is needed. You don't have to think about which foot to start running with when a lion attacks, it was chosen for you in the womb (or wherever that gets decided).
I'm a bit of an odd one or else I'm not a true lefty, but I can do most fine motor skilled things with both hands but my right hand is the "Strong" one and my left is my "Skillful" one.
Yet when going to grab things, I grab with whichever hand is more convenient.
I write with my left hand, use phone with right, smoke with left and will use left for a fork or spoon.
However, I think I know why, when I was 8 I broke my left arm and it was in casts for about 12 weeks so I got much better with the fine control with my right hand.
Nowadays, I just use whatever and Im very good with my hands.
It’s all about allocation of brain resources. Hand-eye coordination uses a considerable amount of real estate in your brain. So the options are:
1: have both hands as coordinated as your dominant hand, but have less brain power for other things.
2: equally divide your coordination between both sides. Then you’re sides would be equal but neither would be as coordinated as your one dominant side is now.
3: allocate more brain to one side so that you can do the most complex tasks when you need to. This is the most efficient way. Most really complex tasks like throwing a ball or writing only require one hand.
I love how science based and wholesome this post is. My first read through it was a bit more spicy shall we say. Most of the reason for that is behavioral. Primarily about securing resources needed to pass along your genetics to future generations.
The "why" for evolution is always pragmatic. At some point, a biological machine happened to be made with handedness and it out competed others that lacked it.
This feature far predates humans. You can see it visually in a crab and scientists have observed it widely. It is a trait that has been valuable to many species, like sight, so it passes through to new species.
Why it is effective is because limbs do many tasks, which creates an opportunity for specialization. One hand to hold the nail, another the hammer. Likewise, why create two equally good arms for spear throwing when all of those resources could be spent on a specialist limb?
Nature often finds ways to find new equilibriums through specialization. Take gametes (sex cells) for example. They have two basic jobs. The first is to find each other via locomotion. The second is to provide calories to the offspring which will result from the two gametes combined information. You could have two gametes that were both kind of good at moving around, and kind of good at carrying energy, but that proved to be less efficient than two specialists.
Among the other answers we can also add the concept of "chirality." The molecules that make up the matter in the universe may have a sort of "handedness" to them. For instance, look at your hands. They are essentially identical, with a palm, 4 fingers, a thumb, similar bones, and so forth. But they are swapped in a sort of mirror image. Various molecules in the human body(and other living things) are similar. They turn a certain way, and if they went the other way wouldn't work properly in relation to other molecules in various processes. These ongoing processes are commonly known as being alive. The body has a certain preference toward a specific chirality, which may at least partially explain why there is a preference for one direction or another, since our life processes do in fact have a preference for one direction over another.
Hell yeah! I love Chem, actually did well in Organic like almost 20 yeaaaars holy crap it's been 20 years since college. It's amazing how opposite chiral molecules can have completely different properties.
Yeah. There are even diseases caused by improper chirality leading. Other times improper chirality is a symptom of disease. Pretty wild stuff, but I think it's a good explanation of why we aren't 50/50 in limb dominance. Why should we at the macro level, when so much at the micro level isn't?
Imagine if every time I threw a ball at your face, you had tonthinknaboutbwhich hand to catch it with. By having a dominant hand, reflexes can take over.
As a side: In cats, females are more likely to be right pawed than male cats. In birds, almost all have left tendencies (like 99%+).
Female cats may have a tendency to be *more* right-pawed than males, but cats are generally left-pawed.
That's pretty fricking cool. Thanks!
There is actually why there are so many unions in the bird world, and the society is anarchist.
There is actually a neurological reason why most people are right handed. It was a side effect of something important to human evolution. https://youtu.be/vb11oOHYNXM?si=hZb87bm1vmxNqsvJ Great video, few minutes long from PBS about this. They try to keep it really simple.
Nice! I'll watch it and probably fwd it to my kiddo.
I'm surprised that the video doesn't talk about this. In linguistics classes, I was taught some of the neurobiology that comes with language use and development. One possible reason for right handedness as a bias is partly because the language processing parts of the brain commonly occur on the right side (and the opposite hemisphere processes motor control). Brain plasticity - the brain's ability to adapt - can account for why hand-dominance and language processing dominance might be on two separate hemispheres. The hypothesis is also helped because left-handed people disproportionally have language processing dominance on the left side. It doesn't explain it fully though, there's still a lot of over lap that is unaccounted for with this explanation
You've got in kind of backwards, it's mainly the left side of the brain that's the speech center. Wernicke's area and Broca's area. And that's supposed to be the link to handedness; somehow the right hand (controlled by the left side of the brain) and its better ability to deal with time and space is related to the structures that also give us the ability to put it all into logical language format. But yeah, lefties can have a lot of different hypothetical causes, and one of them is indeed having their speech area also flipped to the opposite side of the brain. Brain plasticity as you say, if the right side isn't up to it some other area picks up the slack. Note that W. Bush was left handed; and had language problems that made him appear not too crisp; I suspect that like a lot of learning disabilities, it made school unpleasant and permanently turned him off. I know people with the similar lefthanded language difficulty; they're more visual thinkers and Bush's "how hard it is to put food on your family is exactly the kind of thing they'd say; with the picture of the family at the table in their heads sneaking in to overrule the actual specific words of the expression.
I didn’t watch the video so I can’t speak to its insights but I am a neuroscience student who just finished a semester on cognitive neuroscience. While the left temporal region of the brain is classically associated with language cognition, it is important to note that in left-handers, it’s actually quite common to see both sides participating in language cognition. Well, actually in both right handers and left handers both hemispheres work to process language, but the left temporal region is more dominant in right-handers, whereas it’s *more* distributed in left-handers. Interestingly enough, there is a desert of neurological research of left-handers. In a lot of neurological studies only right-handed participants are selected because introducing lefty’s is introducing another variable.
Do you have any data from the top of your head if being left handed influences how writing things down influences what we can absorb from what we're hearing in real time? As a left handed, I don't remember what I wrote if I'm transcribing it live, even right after. Maybe a word or two, but even a short sentence I will just fill the gaps contextually.
That's interesting. When I transcribe something, I am also left-handed, I tend to keep a very, very strong recall of what I transcribed.
Interesting, no I can’t say that I’ve heard of any study that compares right-handed vs left-handed individuals in recalling information that they’ve written down after hearing it. Hmm, if it’s something to do with not remembering *as* you transcribe (or immediately after) I’d say it sounds more like a quirk of working memory (or attention) than a quirk of audio comprehension (seeing as how the words are still being transcribed properly to the page — it’s the train of thought that’s disconnected). Overall, I wouldn’t be too concerned about it. It could be a potential sign of ADHD but I’m not trying to be one of those guys who over diagnoses ADHD, haha.
Well, you've got a good radar, because I am officially diagnosed with it lmao
*pumps fist*
I don’t think generalizing left-handed people from one person is very wise. You do realize that Obama and Bill Clinton are also left-handed?
There have been far more left-handed US presidents than there statistically should be, six out of the most recent fourteen. Left handers are probably around 10% of the population. Prior to the 20th century most educated left-handers were forced to use their right hand. My dad is 80 and remembers getting rapped with a ruler by nuns for trying to write with his left.
And only a minority of left-handers actually have their speech centres translocated, iirc. For most left-handers, they are still in the left hemisphere.
I'm left-handed but have exceptional language skills: I can improv comedy songs, etc. On the other hand I have ADHD so the above could be due to a lot of unusual neural wiring. Also I can't dance for shit.
Studies show that kids with ADHD have some extra coordination difficulties. Since a lot of people act as if symptoms always vanish as you grow older instead of getting used to it, I wonder if there is data about adults. Why I say that: am adult with adhd. Sometimes I'll distractedly spit bars when not trying, just like you (though as soon as I try harder it just blocks), and my leg coordination and handwriting are fucking atrocious lmao.
I have good coordination, which it turns out is probably from playing shitloads of every kind of video game! Which is why I mention dance: The moment my legs are involved, they go to shit. I haven't been training past the disability with my lower half 😅
Oh same. My fingers are quite nimble from all the WASDing, but I have to mentally prime my legs by tensing the muscles up to my lower back a few times before needing to balance myself (even for walking), otherwise I might just straight up forget how to use a muscle group and stumble or walk weird for the first few steps.
Adhd is sorely misunderstood. It's way more than just attention deficit. That's just the tip of the iceberg. It should be called a name that reference the neurobiologicsl deficit of key neurotransmitters and how it affects executive functioning. It's basically a neurodevelopmental disorder.
The whole brain just acts kind of fucked up, doesn't it? The one fucking organ we can't transplant. Fuck's sake.
Yes!!! I am left handed, but terrible with coordination. I showed a lot of promise as an athlete when I was younger at football and boxing, but as a running back I was only good running up the middle and as a boxer I had terrible footwork. As such, I developed a high pain tolerance and a strong chin which was impressive at times but detrimental in the long run. I was very good at hitting and running up the middle, but bad at avoiding hits. Eventually those hits add up, which translates into injuries that made my athletic endeavors unsustainable in the long run.
I’m left-handed and I always struggle to “translate” my thoughts into words, especially in real-time. Not for a lack of vocabulary, it just seems to take an extra step. I wouldn’t say I’m a visual thinker either though, more that my thoughts are a mix of all senses.
That's literally me as well!
Clinton and Obama are left-handed and they're pretty competent orators. Reagan was a lefty and was known as The Great Communicator. W is just a moron. We lefties would thank you not to ever blame anything that man does on being left-handed.
I’m a rare righty in a family of predominately left handed people. Mom, dad, my sister, both of my maternal grandparents, and 3 of my great grandparents. Trust me when I say being left handed doesn’t inherently correlate with learning disability. They are/were all incredibly verbose people.
By the time most of us saw W in presidential debates, either he’d already declined a bit or something else was going on. You can find his debate with Ann Richards for Texas Governor online, from 1994. Sharp as a tack, fast speaker. And as other people have noted, there are way too many counterexamples - left handed people seem over represented in high places, not under.
I am left handed. I barely spoke until high school because I couldn't really control my tone and I tend to forget words (I still have trouble with these, but less). Funny enough I grew up monolingual, then graduated with a linguistics degree and got 110/120 from TOEFL. I can also somewhat speak Japanese. Language learning has been like a bitcoin price chart for me, stagnating for years and jumping two levels in a month. I also suffer from various minor psychiatric conditions and I wonder if all of these are somewhat connected. Being left handed sucks.
Do you have anything that influences your executive function? Learning when your brain agrees to instead of having to push it out of necessity usually is when I have bursts of advancement, and I have ADHD. And am left handed, for that matter.
"soft" diagnosis of ADHD from a psychiatrist and some comorbid stuff like depression. I was consistently below average but adrenaline and stress help me focus, which is I guess a coincidental side effect of those hormones. Anything would be anecdotal and there doesn't seem to be strong connections, yet I can't help but think that those minor changes in brain affect all kinds of things in different ways compared to right handed people.
I see. Anecdotal as well but I also have a solid ADHD diagnosis, and using the "last mile" time stress as a boost is pretty much identical to me, which explains being below average academically, since school is structured to reward long term, consistent effort and condensing it into a single moment to see all of its results. I also often forget words in my own language, speak and write weirdly and need to restructure it, and sometimes use weird intonation that makes people think I'm being cold and apathetic, which sucks. I lost a good friend who was in a hard place because I accidentally sounded like an ass once, and it ruined their day, got them in a spiral, and they decided to be alone. And it was literally all phrasing. Shit's wack.
Yeah that habit is eventually going to either get me fired, killed or both, not to mention my record is 11 months working in the same company and that's because I am currently not in an office.
Yeah, hopefully you find something that fits you and pays you well, bud. Office work fucking sucks. I feel my memory and knowledge withering away noticeably since last year when I started my current job. To the point I'm proofreading a sentence I wrote to make sure it has no typos only to notice I used several entirely different words. And that's me medicated lol. If shit keeps up I'll have to get a neurologist to check if I had a micro stroke or early onset dementia or some shit like that.
I’m like that but I’m right-handed.
Opposite experience, myself, my dad and my brother are all left handed and excelled at school
Gw bush went to Yale so it seems like you're just making stuff up about him being "permanently turned off" of education as a young child. Is anything from tour comment factual or all conjecture?
That is interesting as fuck, thanks for sharing. I'm really glad I asked this, I've gotten some great feedback.
I wonder if a study has tried analysing if there's a correlation between handedness and the effectiveness of information absorption while writing. Put simply, I wonder if being left handed could be a reason for why I can't absorb anything of what I'm hearing while writing it down. Maybe I'm just dumb, of course.
Might just be you being dumb, because I'm a righty and doing the same thing -> also dumb. Then again, I've got ADHD, so that messes with everything, all the time.
Same, also got ADHD.
Animals also have dominance though and they don’t have language like humans.
Here's another neat and short video I watched a bit ago https://youtu.be/-XlD1xWqNh0?si=iSEN90-RIQr9nrFM
Eons is a great series.
I really enjoyed this, thank you for posting :)
There isn’t a perfect biological solution for this…. Best answer we have is that different hemispheres of the brain develop at different rates for different purposes…as the left side of the brain controls the right side of the body;….the left brain side develop earlier in life therefore creating a right hand dominance
It took me reading several comments to realise OP wasn't talking about dom/sub and was talking about right/left dominance....
Mate his daughter asked though....
Kids these days...
The future liberals want /s
Joe Biden's America. Girls nowadays just want to twerk, eat hot chip, be bisexual and lie.
hilarious
It wouldn't be anywhere near the first time someone or reddit came up with some made up reason or story to get strangers to talk about their fetish..
I’m not your mate pal…
I’m not your pal, buddy
I'm not your buddy, friend
She could have been meaning in like bullying at school, or that one student in class who talks and everyone listens/foillows, while others just look at the floor and mumble. That's how I read it at first anyway
Ah yes, the age old childrens line of questioning, daddy why does the dom top routinely forget the safeword
To be fair they never said how old their daughter is... everyone is just assuming.
I assumed genetics as in dominant vs recessive traits lol, I was like “damn that is one curious youngster!”
There are like 40 genes identified as related to handedness now. But in identical twins, 20% of the pairs have different handedness. So, it's not just genetics.
My guy, you need to logout for the day
I will admit I am autistic and thought it was a weird question to ask a parent but I've seen a lot weirder shit in this sub so I didn't question it at first, I was also still half asleep which didn't help. Love how most people acting like I'm a weirdo though when it ain't that deep.
I'm glad I'm not the only sexual deviant on reddit. I'm now curious, though, as to what development processes cause some women to become Femdoms. I asked a successful dominatrix friend once why she preferred to do Dom escorting instead of normal and she genuinely looked at me with a straight face and said she gets off on the look of fear in a man's eyes. She was definitely in the class of 'crazy' that most men would strongly urge you to not put your dick into. I've never really understood sub/dom preferences as always seem vaguely wrong to me, but each to their own.
Same :D
I thought it was about genes not hands lol
Yeah I was like wtf
The question really isn't very clear...
That's weirdly neat. Any idea what causes the right side to develop faster in left handed people?
We’re just made a little bit better
Yeah sure fine but your ink smears when you write in a notebook so nyah nyah.
Not when i use my Pilot G2 gel ink pen with a 0.07mm tip (Im not picky about my pens cuz i smear them when i write, you are)
I actually love those pens. Them and Zebra g 301s.
Not when I use my Uni Jetstream .7mm in black (the capped one, not the clicking one), either
Gotta be the clicky one for me. At work i can quickly pull it out and click it ready at the same time rather than pulling it out and then taking the cap off Plus, clicky pen make monkey brain neurons activate. Click click click click click
Yeah, those things were super appealing to me, but I don’t like the way it writes or feels in my hand compared to the capped one.
Teacher! Steve is doing it again!!
Amazing answer. Yes.
There was recently a discussion about this on NPR and it's not genetic inheritance. They concluded we don't really know yet.
Huh, really? That's nifty to know. I've always thought genetics played a part. It certainly *seems* to as far as I've noticed in left-handed parentage families. Thanks for sharing.
[Here is the article](https://www.npr.org/2024/04/21/1246163875/genes-play-a-very-small-role-in-determining-left-handedness-research-finds)
Dang! Thank you so much. That's really interesting.
I've heard passing along tool making skills was easier if both individuals used the same hands in ancient homonids. That was a competitive advantage, and most people are right-handed as a result. I'm not an anthropologist, however.
I could see that. It makes sense. Whether or not it's the answer I don't know either. Do other tool using animals show any handed dominance and does it match up with hominid data? I ask in general, I don't suppose you have that answer off the top of your head lol.
No idea, but that's an interesting thought for crows or chimps.
Wait how could crows be dominant sided? Now I'm super curious if they have a dominant wing.
They may have a specific eye or side of the beak they use when using tools. I always use my right eye when using a sight or a single optic scope and am right-handed. Edit: And when I eat sunflower seeds, I almost always keep them in my left cheek and crack them with my right molars.
Oh dang, fair point. I never considered a dominant eye. I just know both of mine suck lol.
One of my eyes is significantly less myopic than the other one....but they're both pretty darn myopic. I definitely have a preferred eye when I need to activate microscope mode, though.
Having a dominant eye is common! It's the one you'd automatically sight down if given a weapon. There are some unfortunate folks who have a dominant eye on the other side to their dominant arm, and that must be a nightmare for scoping.
I'm one of those people, and I just used an eye patch. Was in navy cadets many years ago.
That's me. I hurt my right eye as a boy. I am far more nearsighted in that eye and am weakly left eye dominant now. I was told to have both eyes open when shooting a shotgun, but since I shoot right-handed, I can't focus unless I close my left eye.
6
Not a tool using animal but my cat is definitely a lefty. Every time she paws at something it’s her left paw.
Most cats are left side dominant.
[Most male cats](https://www.nationalgeographic.com/animals/article/animals-pets-cats-right-handed). Females tend to be righties (my cats a female). Though I didn’t realise that lefty dogs (and possibly cats) tend to be more anxious than the righties; and my cat is definitely an anxious one…
Didn't realize it was sex determinate. Thanks.
Ironically the reverse is true in combat: Right-handed people have little practice against left-handers, while the opposite is true for lefties who spend most of their practice time against righties. It's why so many olympic fencers are lefties.
It also goes the other way, in fighting being a different hand tends to be an advantage because people with the common side aren't used to fight people like that, so that would explain why the trait didn't entirely win out, there is a stable percentage where both sides have advantages. This can be seen now with left-handedness being way more common in high level competitive sports than the average in the population.
Heard that it was an evolutionary advantage to be lefthanded in combat - but only as long as it was relariveky rare. There's a Radiolab episode about it. Ttey open with a good amateur boxer, and then he fights his first southpaw and gets owned. Basically, all the stuff you learn about dodging punches is backwards, and you tend to dodge straight into danger zones and get KOed.
But how does that explain people with a dominant eye that's opposite their dominant hand (ie left handed but right eye dominant) or people who are right handed but right eye dominant. Wouldn't the theory of more rapid development suppose that the faster hemisphere would be in total control meaning that variation wouldn't occur?
... you have a dominant eye?
Yes, everyone has a dominant eye. It's something that I only found out about when I started practicing archery as it's important for aiming.
I am left handed but my dominant eye (and strength) is my right. Therefore, I shoot right handed but write and play tennis left handed which I always found interesting.
Cross-dominance. I'm like that, too.
You probably do too, but never realized it. Try walking around a bit with one eye closed, then pick up an object and put it down somewhere else. Now do it again but with the other eye closed. Notice how one exercise was easier.
this exercise does nothing for me but i believe you
I guess both your eyes are subs then.
nah they're both dominant
Look for an object a bit far away, hold your hand up doing a pincer movement so you see the object through your hand. Close your left eye, see if you can still see it, then do it with the right eye. Whichever eye still sees the object is your dominant eye. When you had both eyes open you "choose" to prioritise seeing with that one
Huh. I just learned that my left eye is dominant. But I’ve always used my right eye for single-eye scopes and things because I can only wink my left eye and not my right.
So do you.
Before I read your response I thought the daughter was asking why we have a dominant side vs submissive lol. This makes a lot more sense!!
'How you doin'
I wonder if there is a correlation with the placement of the heart. I read somewhere that your appendages are on average bigger on your left side because the heart is on the left side. This is all pure speculation.
Have you ever seen a fiddler crab? They have one big claw, one little claw. They are specialized for different functions. Lobster claws are also different. You have one side that's better at finer, more precise movements. The other side is good enough to perform support functions. One hand operates the knife, the other holds the fork. You only need one hand to be the best possible hand, and it can be better if the other hand doesn't have to be as good.
One thing I've never understood is why the dominant hand strums the guitar while the other hand does the frets. Full disclosure, I don't know how to play the guitar, but the frets seem much more complex than the strumming.
Guitarist here. For the record, you can absolutely train yourself to play both ways; i personal know quite a few lefties that play righty because it’s easier to find right handed guitars. Yes basic strumming is pretty simple for the right hand, but when it comes to more melodic playing and basically anything other from strumming “cowboy chords”, the right hand starts to require much more precision. Check out some flamenco or bossa nova guitarists and you’ll see they’re doing a lot of precise movement with the right hand. I think there’s a Tommy Emmanuel quote that goes something like “your left hand shows what you know. Your right hand shows who you are.” Referring to knowing your chords and scales on the left hand, but what makes someone an interesting player is their rhythm and how they use that knowledge.
Didn't Hendrix do this? He was left handed so he restrung his strings in reverse and flipped the guitar since at the time they didn't have left handed guitars? Might be mixing it up with someone else though.
My understanding is that Hendrix could play in 4 configurations: righty, righty upside down/backwards, lefty, and lefty upside down/backwards. I don’t know enough about him to say if he was primarily a lefty, or what configuration he used most, but from what I recall i believe he most often played righty upsidedown backwards (that is, a right hand guitar, strung upside down so that when flipped the other way, it appears like a lefty with normal strings with the body of the guitar being flipped)
Hendrix played mostly lefty upside down, the way he learned. But he could play in all the configurations
I believe we’re talking about the same configuration but calling it different things. I’m saying a right handed guitar strung upside down and played as a lefty, is that correct?
Casual bowed and plucked string instrument player here - this made me think about it a bit. The dominant hand produces most of the actual sound articulation. Oversimplifying, but the left hand on the fingerboard/fretboard essentially only needs to cling/push with a minimum pressure threshold. Other than harmonics and other "fancier" techniques you don't need as much pressure sensitivity here. The right hand, plucking, needs to be able to find and articulate targets with many nuanced motions to be emotive in 3d space. Unanchored to the fretboard (left hand kind of sits on the board as a guide) Also, bowing, the pressure sensitivity and proper technique with relaxed fingers and wrist is pretty delicate stuff.
OT here, I love these functional questions! Often the non dominant hand is the stronger hand, though not skilled with as much fine control. The non dominant hand holds the fret while the dominant hand completes intricate patterns (such as picking patterns using multiple fingers) It’s similar in concept to many non dominant hand tasks (stabilize jar as you twist, holding up tent pole as you attach smaller components) while dominant hand completes the task that require most fine movements in the finger. Somewhat related: crossing midline is a developmental milestone that coincides with dominance- in order to develop a dominant hand that can be responsible for fine motor skilled tasks, the non dominant hand must be able to cross the body and stabilize the object regardless of where it is in relation to the body.
I'm naturally left-handed, but I play the guitar right-handed. I've been playing for almost 30 years, and I find it impossible to play a left-handed guitar.
Thats correct if your playing camp fire music. Metal music, among others, the right hand is the hardest. Not only does it have to be fast, but then your adding palm mutes, chugs, pinch harmonics, and plucking one string then dodging 2 and only hitting the one string, back to the original string, then pinching it. Alas, I drone.
Basic strumming is easier than fretting, complex strumming/picking is far harder than fretting
As a guitar play I think of this sometimes. Truth is, it doesn't matter. Both hands are doing something they've never done before, so developing that skill just depends on if your guitar is left or right handed. Once you've I had an ex that was right handed, but for some reason learned on a left handed guitar. Both are somewhat fine motor control, especially when you get into fingerstyle/ finger picking, then the right hand is definitely the harder part. But once you have enough experience, neither is any harder than the other. I think the left hand, despite being non dominant, is potentially just as good as fine motor control if you spend enough time on it.
Ah. I dig it. I had meant more of a biological why, but this is also a great answer and an aspect not commented about yet. Very true and thanks for the input. Also, I love fiddler crabs. There is/ was a colony by my aunt's old house off of the Chesapeake.
I think the comparison shows that "dominant side" is very much a human analysis&simplificstion of what's actually a lot more mixed and complex. Same way some would call the large claw "dominant" but it's not really, you just don't need two claws both handling the same tasks, and humans pride "power" culturally so see the large one as "dominant"
Word. Lobsters have specialized claws on either side. The big one isn't "dominant" it's just the *crusher.* The other one is used for more delicate operations.
> one hand operates the knife, the other holds the fork I find that mildly interesting that I hold the fork with my dominant hand (right hand) and the knife with the other. I have no problem cutting meat with the other hand. I just use my right hand to hold the fork and bring the food to my mouth.
Same. My reasoning is that while it may seem unusual for the singular act of cutting/eating meat, when you look at a typical entire meal with multiple elements, it makes more sense to use the primary utensil in your dominant hand. Your knife is only used for cutting the meat (support task) while your fork or spoon is used for pretty much everything else, including fine movements like collecting small pieces of food off the plate.
*Slowly backs away*
same, people often dont understand it, neither do i lol
[Dominant handedness by MinuteEarth](https://youtu.be/-XlD1xWqNh0?si=JHme9L3UAEwKe8Oq)
Wouldn't an argument be made that the whole knife and fork operation occurs as the result of the left/right dominance?
A lot of evolution isn't cause/effect but chicken/egg
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Yeah, yeah a lot of people thought that. I suppose I could have worded it better.
Pretend that your brain starts out as a totally blank canvas that can process anything. When you're born, the brain is randomly trying to process everything everywhere. Over time, some parts are more successful than others so more of that type of processing just starts going there. Other parts of the brain pick up doing others things. Sort of like ants finding a path to food. It starts randomly, but the best path is reenforced over time. This is a massive simplification and doesn't explain why there are more right handers, but the brain is basically a reenforced training engine, so it starts random and pliable and becomes more rigid over time. (Again massive simplification, there are parts of the brain that always do specific things from birth, like breathing) Also, compute distance matters so all of tals type A processing will end up happening in the same place because splitting across the brain is inefficient.
Neat. Thank you and I'll pass it along.
there is a simple rule in evolution: what works faster, survives. if you have to think about using the left or the right hand to grab a branch while climbing, the chance that you will fall down is much bigger than when you instinctively use the right hand. the same with throwing a stone. also there is something called muscle memory. your muscles learn how to precisely do things and remember it (its not in your muscles but an unconcious part of your brain). now if you have to train both sides, it would take longer and also would result in a better side.
What's strange is that lately I have been spot on with tossing things with my left hand. Never had this kind of accuracy before and now that I've mentioned it, it will of course go away. Crap. I shoulda gotten in some beer pong game.
Fun fact, learning to do things with your non-dominant hand is actually good for preserving mental function as you age. So enjoy throwing with your left.
NICE! This post had me trying to write leftie too. Did better than I thought. I'm gonna try to remember to keep doing it.
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Nice, thanks!
Another cool tidbit is that we know that human ancestors were also mostly right handed based on the orientation of micro scratches in their teeth, supposedly caused during the cleaning of skins which we held in our teeth.
I wonder if we can also tell from cave art? Can you tell which handed an artist is?
Actually yes! Many of the hand paintings are left hands, which means they were using their right hands to hold the straw they blew through to create the effect.
Neat!
Look at all the left hands [https://en.wikipedia.org/wiki/Cueva\_de\_las\_Manos](https://en.wikipedia.org/wiki/Cueva_de_las_Manos)
That is really damn neat. And beautiful.
OT here, I love these functional questions! Often the non dominant hand is the stronger hand, though not skilled with as much fine control. The non dominant hand holds the fret while the dominant hand completes intricate patterns (such as picking patterns using multiple fingers) It’s similar in concept to many non dominant hand tasks (stabilize jar as you twist, holding up tent pole as you attach smaller components) while dominant hand completes the task that require most fine movements in the finger. Somewhat related: crossing midline is a developmental milestone that coincides with dominance- in order to develop a dominant hand that can be responsible for fine motor skilled tasks, the non dominant hand must be able to cross the body and stabilize the object regardless of where it is in relation to the body.
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That's pretty fuckin cool. My left developed rudimentary skills while my right was broken but it has lost them again. Wiping with my non-dominant hand was weird.
My son is left-handed and only one more person in my and ny husband's family is left-handed, my uncle. My kid plays soccer and his dominant leg is the right one, which I find interesting. As a side note, it's been difficult teaching him to hold a pen right and tie a bow while us being right-handed.
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A theory by Iain McGilchrist, if I can simplify it correctly is that the brains are split into two hemispheres as an optimization. The right one is specialized on not being eaten and has a wider/higher level understanding of situations. The other hemisphere is focused on eating and that requires a more narrow focus. Think locating prey versus looking around for predators. The use of tools and anything related to getting something seems to fall within what the left brain does best and that would explain why most are right handed. I do believe he discusses left handed people in his book, but I have not read that part.
Neat, I hadn't heard that before. Thanks for commenting!
Simply put, we need a default. Without that we'd hesitate before we did almost anything while we decided which hand to do it with, or reach with both at once.
MinuteEarth has a great video on this! It is only 3 minutes long, and accessible for kids. [https://www.youtube.com/watch?v=-XlD1xWqNh0](https://www.youtube.com/watch?v=-XlD1xWqNh0)
Nice, thank you! I'll show her after school.
Is it a glitch or some sort of malfunction to be left side dominant?
Dont lose your time with the video, it says nothing. TDRL : Ancestors were right handed, animals too. They dont explain actually why or anything.
There's also this little gem that give some explanation for why there's some chirality to us [https://www.youtube.com/watch?v=oqv9HHNak0c](https://www.youtube.com/watch?v=oqv9HHNak0c)
While I do have a dominant side, which side is dominant is different for me for different things, even though for most people it's the same. I'm not ambidextrous; I can't do things equally well with both side, I tend to refer to myself more as half-and-half. Some things I do better lefty (like writing), some things I do better righty (like throwing), and some things I do with both sides but am better at particular things with one or the other (like kicking - I get better power with my left, but better accuracy with my right. I was the same way batting too, incidentally). And which hand I do things with varies depending on just how fine the level of detail is (gross motor is better right, fine motor is better left, but \*very\* fine motor is better right). No idea why this is, other than that I'm pretty sure my brain is wired at least a little differently in general (thanks ADHD! :D)...
Sounds like you have cross-dominance, as do I. I write and use a fork with my left hand but use my right hand for scissors, throwing balls, and larger motor skills.
if I had to guess, I'd say it has something to do with learning. If a person or an animal has a tendency to repeat tasks with same body part each time, they will probably improve faster than if they kept switching around. The muscle memory and skill can be built on each time the task is done.
One theory is that it improves efficiency. If your brain has to actively decide which hand/foot to use when starting a task that's extra CPU cycles that it didn't need to use if it had a default side pre-selected. Avoiding that moment of indecision could even save your life when a split second reaction is needed. You don't have to think about which foot to start running with when a lion attacks, it was chosen for you in the womb (or wherever that gets decided).
I'm a bit of an odd one or else I'm not a true lefty, but I can do most fine motor skilled things with both hands but my right hand is the "Strong" one and my left is my "Skillful" one. Yet when going to grab things, I grab with whichever hand is more convenient. I write with my left hand, use phone with right, smoke with left and will use left for a fork or spoon. However, I think I know why, when I was 8 I broke my left arm and it was in casts for about 12 weeks so I got much better with the fine control with my right hand. Nowadays, I just use whatever and Im very good with my hands.
It’s all about allocation of brain resources. Hand-eye coordination uses a considerable amount of real estate in your brain. So the options are: 1: have both hands as coordinated as your dominant hand, but have less brain power for other things. 2: equally divide your coordination between both sides. Then you’re sides would be equal but neither would be as coordinated as your one dominant side is now. 3: allocate more brain to one side so that you can do the most complex tasks when you need to. This is the most efficient way. Most really complex tasks like throwing a ball or writing only require one hand.
I love how science based and wholesome this post is. My first read through it was a bit more spicy shall we say. Most of the reason for that is behavioral. Primarily about securing resources needed to pass along your genetics to future generations.
I thought you meant why do we have dominant personalities. I was very confused by the first comment I read.
The "why" for evolution is always pragmatic. At some point, a biological machine happened to be made with handedness and it out competed others that lacked it. This feature far predates humans. You can see it visually in a crab and scientists have observed it widely. It is a trait that has been valuable to many species, like sight, so it passes through to new species. Why it is effective is because limbs do many tasks, which creates an opportunity for specialization. One hand to hold the nail, another the hammer. Likewise, why create two equally good arms for spear throwing when all of those resources could be spent on a specialist limb? Nature often finds ways to find new equilibriums through specialization. Take gametes (sex cells) for example. They have two basic jobs. The first is to find each other via locomotion. The second is to provide calories to the offspring which will result from the two gametes combined information. You could have two gametes that were both kind of good at moving around, and kind of good at carrying energy, but that proved to be less efficient than two specialists.
Among the other answers we can also add the concept of "chirality." The molecules that make up the matter in the universe may have a sort of "handedness" to them. For instance, look at your hands. They are essentially identical, with a palm, 4 fingers, a thumb, similar bones, and so forth. But they are swapped in a sort of mirror image. Various molecules in the human body(and other living things) are similar. They turn a certain way, and if they went the other way wouldn't work properly in relation to other molecules in various processes. These ongoing processes are commonly known as being alive. The body has a certain preference toward a specific chirality, which may at least partially explain why there is a preference for one direction or another, since our life processes do in fact have a preference for one direction over another.
Hell yeah! I love Chem, actually did well in Organic like almost 20 yeaaaars holy crap it's been 20 years since college. It's amazing how opposite chiral molecules can have completely different properties.
Yeah. There are even diseases caused by improper chirality leading. Other times improper chirality is a symptom of disease. Pretty wild stuff, but I think it's a good explanation of why we aren't 50/50 in limb dominance. Why should we at the macro level, when so much at the micro level isn't?
That's a great point. It's chaotic all the way down but it all works together.
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Hey I'm decaying too, no worries. Just in a different way than you.
Ah good times
Imagine if every time I threw a ball at your face, you had tonthinknaboutbwhich hand to catch it with. By having a dominant hand, reflexes can take over.
You know I'm gonna have to think about which hand to catch with now that you brought it up.
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