Beta
×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

The Science of Handedness

samzenpus posted more than 2 years ago | from the southpaw-statistics dept.

Math 258

Hugh Pickens writes "Representing only 10 percent of the general human population, scientists have long wondered why left-handed people are a rarity. Now a new study suggests lefties are rare because of the balance between cooperation and competition in human evolution and a mathematical model was developed that predicts the percentage of left-handers by sport based on each sport's degree of cooperation versus competition. 'The more social the animal—where cooperation is highly valued—the more the general population will trend toward one side,' says study author Daniel M. Abrams. 'The most important factor for an efficient society is a high degree of cooperation. In humans, this has resulted in a right-handed majority.' If societies were entirely cooperative everyone would be same-handed, but if competition were more important, one could expect the population to be 50-50 because cooperation favors same-handedness—for sharing the same tools, for example while physical competition favors the unusual. In a fight, for example, a left-hander would have the advantage in a right-handed world. The mathematical model accurately predicted the number of elite left-handed athletes in baseball, boxing, hockey, fencing, and table tennis (PDF)—more than 50 percent among top baseball players and well above 10 percent (the general population rate) for the other sports. For other sports like football or hockey where team cooperation is paramount, it is ideal for all individuals to possess the same handedness. For example, in football, blocking schemes are often designed to protect a quarterback's blind side. As a result, it is beneficial for all quarterbacks on the roster to possess the same handedness to minimize variations of the offensive sets. 'The accuracy of our model's predictions when applied to sports data supports the idea that we are seeing the same effect in human society.'"

cancel ×

258 comments

Sorry! There are no comments related to the filter you selected.

first. (-1, Offtopic)

Anonymous Coward | more than 2 years ago | (#39839371)

posting a big pile of first.

So why the right hand? (3, Interesting)

cpu6502 (1960974) | more than 2 years ago | (#39839385)

Why isn't everyone left-handed? That too would be beneficial in a cooperative society (shared tools). Maybe millions of years ago, the left-handed tribes died out. (Maybe they called themselves Neandertals.)

Re:So why the right hand? (3, Interesting)

CSMoran (1577071) | more than 2 years ago | (#39839463)

Why isn't everyone left-handed? That too would be beneficial in a cooperative society (shared tools).

This probably reflects the assymetries in the human body (heart on one side, one lung smaller, etc). Anyway, if all was in reverse and the majority were left-handed, you'd be here asking "Why isn't everyone right-handed?" :).

Re:So why the right hand? (2, Funny)

Anonymous Coward | more than 2 years ago | (#39839701)

This probably reflects the assymetries in the human body

I'll have you know my ass is perfectly symmetrical, thank you very much!

Re:So why the right hand? (3, Funny)

Anonymous Coward | more than 2 years ago | (#39839467)

And this still doesn't explain why I pee with my left hand and masturbate with my right hand.

Re:So why the right hand? (5, Funny)

Scaba (183684) | more than 2 years ago | (#39839747)

At the same time?

Re:So why the right hand? (4, Funny)

roman_mir (125474) | more than 2 years ago | (#39839899)

And this still doesn't explain why I pee with my left hand and masturbate with my right hand.

- It definitely doesn't explain any of THAT! I believe most people don't pee with their hands.

Good question! (2)

khasim (1285) | more than 2 years ago | (#39839483)

Can a right-handed male and female produce a left-handed child?

Can a left-handed male and female produce a right-handed child?

Is there a percentage?
Right + right = right 90% of the time?
Left + left = left 90% of the time?

Or is it that any combination will result in a right-handed child 90% of the time?

Re:Good question! (3, Informative)

silentcoder (1241496) | more than 2 years ago | (#39839521)

I'm the child of two right-handed people - and I'm neither, I'm one of the 1% ambidextrous people - but I prefer to write with my left hand.

Re:Good question! (5, Funny)

Anonymous Coward | more than 2 years ago | (#39839545)

I'd give my right arm to be ambidextrous!

Re:Good question! (4, Informative)

Pandur77 (1172799) | more than 2 years ago | (#39839649)

All I can say is that I'm left-handed. Both my parents are right-handed and so are both my brothers.

So tell me ... (1)

khasim (1285) | more than 2 years ago | (#39839705)

All I can say is that I'm left-handed. Both my parents are right-handed and so are both my brothers.

So tell me, when you were "in utero" which sports were you most interested in?

Re:So tell me ... (3, Funny)

wmbetts (1306001) | more than 2 years ago | (#39839789)

Dodge the worm.

Re:Good question! (0)

Anonymous Coward | more than 2 years ago | (#39839791)

Wife is lefty. I'm a righty. Both kids are lefties (well, the youngest hasn't chosen yet, but favors left).

Re:Good question! (4, Interesting)

AJWM (19027) | more than 2 years ago | (#39839875)

I have (fraternal) twin sons. One is right handed, one left handed.

 

Re:So why the right hand? (5, Funny)

Anonymous Coward | more than 2 years ago | (#39839487)

"Why isn't everyone left-handed?"

    I might say that it's a sinister plot, but that would be gauche of me.

Re:So why the right hand? (1)

Gilmoure (18428) | more than 2 years ago | (#39839605)

*golf clap*

Re:So why the right hand? (1)

Mooga (789849) | more than 2 years ago | (#39839515)

Why is there no mention of genetics? It's common knowledge that many people who were naturally Left Handed were forced to switch to be Right Handed back in the day. The whole shared tools is hog-wash. How many tools do you know of that depend on handedness? I can think of only a few, and none that are important: computer mice, modern fencing weapons, golf clubs.

Re:So why the right hand? (5, Informative)

dcollins (135727) | more than 2 years ago | (#39839577)

Writing, scissors, buttons, car shifter (first few I thought of in 10 seconds).

In particular, writing: It's designed that right-handers are dragging the writing implement behind their hand in a smooth gliding motion. For left-handers we're smashing the point into the page in front of our hand, making it highly variable and irregular (a non-equilibrium), and then also smearing the hand over what we just wrote. Truly a pain. That's specifically the reason why my uncle (for example) was forced to switch by my grandparents tying his left hand behind his back.

And personally, I think that writing is the most important of all human tools.

Re:So why the right hand? (0)

Anonymous Coward | more than 2 years ago | (#39839625)

What about languages that are written from right to left? Do right-handers have smearing problems there?

Re:So why the right hand? (1)

Soporific (595477) | more than 2 years ago | (#39839633)

You've obviously never seen my writing, it would be described as anything but a smooth gliding motion and I'm a righty. ;)

~S

Re:So why the right hand? (1)

houghi (78078) | more than 2 years ago | (#39839655)

Writing the way we do is because we are right handed. Earlier are left handed, because we chiseled it out of stone. That is easier from right to left. At least that is what I learned in school.
However that does not explain writing from right to left in other languages. e.g. Arabic.

It is also the reason schools have the desks placed so the light comes in from the left si during writing you have more light.

Re:So why the right hand? (1)

kaws (2589929) | more than 2 years ago | (#39839667)

Only one thing from what you've said do I object to, car shifter as you put it. I've driven on both sides of the road and had to deal with the stick on both sides. It really didn't bother me at all. The only challenge that I had was staying in the center of the road.

Re:So why the right hand? (2)

AJWM (19027) | more than 2 years ago | (#39839893)

The only challenge that I had was staying in the center of the road.

I'm not surprised, if anyone coming the other way was also trying to stay in the center.

Re:So why the right hand? (1)

RivenAleem (1590553) | more than 2 years ago | (#39839689)

I practised writing right to left and in reverse as Leonardo Da Vinci was known to do, and it felt a bit wierd at first, but eventually it became easier. Obviously I didn't continue past satisfying my curiosity, because nobody would be able to read it easily.

Re:So why the right hand? (1)

Hognoxious (631665) | more than 2 years ago | (#39839773)

Car shifter? Do you mean gear lever?

Correct me if I'm wrong but that's where it is due to which side the driver sits, which in turn is due to which side of the road people drive on, which usually dates from the days when people rode horses (which don't have gears).

AFAIK the Nips, Limeys and Jaapies have roughly the same percentage of caggies as Americans do.

Re:So why the right hand? (1)

AK Marc (707885) | more than 2 years ago | (#39839869)

Car shifter isn't handedness. Otherwise, you are insinuating that drivers in the UK are left-biased. As someone who has driven on both sides, handidness doesn't matter for shifting. It isn't fine motor skills. You might as well complain about how doors are hung, and that's something that even the off hand is perfectly fine with.

Re:So why the right hand? (1)

Smekarn (1623831) | more than 2 years ago | (#39839981)

Well, it's true that the "gear shifter" goes in the middle, and depending on wether you drive on the left or the right side will indeed decide on which side of the stick you will be sitting. However, the reason for driving on the left side can be traced back to the old sword-smacking-days. You would normally pass oncoming riders on the left so that you could either hail them or strike them down with your favourite right hand, so indirectly, gear shifters ARE handedness.

I heard somewhere that the reason why some countries switched to the right side had to do with their king being left-handed, but I can't (or won't, pick one) verify that.

Re:So why the right hand? (0)

Anonymous Coward | more than 2 years ago | (#39839985)

The car shifter is not a valid example. The shift lever is in the center of the car in the USA, and in the centre in the UK.
I have passed drivers test in both countries, and shifted the gears with the opposite hand, or, um, the hand nearest the shift lever, depending on where I sat.

Re:So why the right hand? (0)

Anonymous Coward | more than 2 years ago | (#39839609)

Scissors, plyers, knives..
Corkscrews, can openers
Oven mitts

Re:So why the right hand? (1)

AK Marc (707885) | more than 2 years ago | (#39839873)

Oven mitts are reversible, at least mine are.

Re:So why the right hand? (1)

ObsessiveMathsFreak (773371) | more than 2 years ago | (#39839607)

Define "left-handed" or "right-handed". You can't come up with an unambiguous definition of either.

The only real definition we have is that "right" is the handedness of the majority of the human population. If the whole population was actually "left" handed as we now understand it, they would be right handed.

The short version of this post is, if you ever meet a perfect version of yourself constructed by aliens from radio transmissions, don't shake their hand.

Re:So why the right hand? (5, Interesting)

FrootLoops (1817694) | more than 2 years ago | (#39839919)

if you ever meet a perfect version of yourself constructed by aliens from radio transmissions, don't shake their hand.

For those who don't know, this refers to a story in the Feynman Lectures on Physics. Here's my version; I've taken some liberties.

Imagine you're on the phone with an alien who speaks English, except they don't know what "left" and "right" mean. You want to explain it to them so they know which tentacle they should use to shake the right-handed President's hand if they should ever meet. The alien can be anywhere in the universe, so you can't refer to stellar positions or similar, leading you to devise an experiment for them to perform.

Your initial attempts use gravity, electricity, and magnets, but you notice each experiment comes out essentially the same if you swap "right" and "left"--for instance, you could give the alien instructions for making a clock in hopes of defining "right" using clockwise rotation, except if the alien made the clock exactly backwards by reversing the notion of "left" and "right", they wouldn't be able to tell. A particle physicist happens by and tells you about a magical experiment involving the weak nuclear force that *does* distinguish left and right inasmuch as the experiment fails if the alien screws up "right" and "left" and succeeds otherwise. (For the curious, some more details here [lbl.gov] and here [wikipedia.org] .) Great, problem solved.

"But wait!" the physicist says. "The alien needs to use regular matter instead of antimatter in the experiment. The results will be reversed otherwise! Come to think of it, I have no idea how to tell them the difference between matter and antimatter. If you ever meet them and they start trying to shake your left hand, RUN, since the alien will be made of antimatter!"

Re:So why the right hand? (0)

Anonymous Coward | more than 2 years ago | (#39839619)

There is a theory that the right hand its superior for stabbing an opponent in the heart with a spear. I believe it is a fairly known theory, so Google for it if you are interested.

Re:So why the right hand? (1)

I(rispee_I(reme (310391) | more than 2 years ago | (#39839775)

There is also a theory that using the right hand for complex tasks allows primates to cradle a baby nearer to their heartbeat with their "dumb" hand.

I heard of it in a book of Asimov essays. Somewhere in The Roving Mind, if I remember correctly.

That means we lefties (1)

Giant Electronic Bra (1229876) | more than 2 years ago | (#39839389)

are like the wolves amongst you right-handed sheep, right!!!!???

I'm not ENTIRELY convinced, what about situations where it is advantageous for people to have opposite handedness for optimal cooperation? There seems to be a built-in assumption here that different-handed assortments of people will always have more problems working together. I'm not sure there's a practical way to test this as a general thing though.

Re:That means we lefties (0)

Anonymous Coward | more than 2 years ago | (#39839403)

If you RTFA'd, then you'd see this was taken into account for.

Re:That means we lefties (4, Insightful)

Giant Electronic Bra (1229876) | more than 2 years ago | (#39839781)

No, it wasn't actually...

"Cooperation favors same-handedness—for sharing the same tools, for example. Physical competition, on the other hand, favors the unusual. In a fight, a left-hander would have the advantage in a right-handed world."

This is simply taken axiomatically as a starting point for the study. I see no indication that it was determined by any sort of analysis. I'm not even sure such an analysis is feasible. You'd have to know what activities people carried out in prehistoric times, how, and what the value of cooperation was for each one. There could be various advantages and disadvantages of same or opposite handedness depending on the activity, etc. The entire concept of their study rests ENTIRELY on the validity of this same-handedness is better for cooperation proposition. I'm not saying it is untrue, but without demonstrating it to be true and to what degree I cannot see how any meaningful conclusions can be drawn.

Re:That means we lefties (1)

cpu6502 (1960974) | more than 2 years ago | (#39839497)

Where would opposite hands lead to greater cooperation among primitive man?

I think the point is that left-handed people would need special left-handed spears, knives, et cetera. If they lost their special tool they couldn't just grab a friend's right-handed version, so they'd be left weapnless and get eaten/killed by the lion before they had a chance to procreate. Thus leftie genes would become rare in homo sapiens.

Re:That means we lefties (1)

gadget junkie (618542) | more than 2 years ago | (#39839745)

spears, knives and early swords had no handedness, which in the case of swords is limited to the form of the hilt, which in the case of a modern basket hilt is handed. and remember that in practically all the history of fighting, the relative size of the population gave an advantage to lefthanders, since the simple probability of meeting a left hander was too low for every right handed fighter to be adequately prepared, while the opposite is false, since left handers had plenty of practise working against right handers.
The modern rifle is an interesting case of standardization going against best results: many designs, especially Bullpup [wikipedia.org] , cannot be used by left handed personnel out of the box unless a specific version/modification is available. the only military rifle that does not require a specific version/tooling is the Beretta ARX 160 [wikipedia.org] , which can be modified on the fly without tools to switch side of the loading lever and/or ejection port.

Re:That means we lefties (1)

Giant Electronic Bra (1229876) | more than 2 years ago | (#39839861)

Eh, I have yet to meet a firearm that gave me any more than the most trivial problems. Certainly left-handed firearms are nice, but in a practical sense both sorts work fine. Working the safety on a pistol quickly is probably the least convenient feature of wrong-handed hand guns.

As a lefty, just let me say (1)

Giant Electronic Bra (1229876) | more than 2 years ago | (#39839845)

It isn't a big deal. Most everyday items don't favor one hand or the other. Spears, knives, and even swords pretty much fall into this category, as do quite a lot of other tools. Scissors and similar cutters are sort of an exception. So chances are this wasn't a really large problem. In a pinch you can just use things right-handed (and most lefties are less hand-polarized than righties, maybe do to the convenience of being able to use either hand, for instance I'm perfectly happy doing many tasks with either hand like cutting with scissors).

As for greater cooperation if you have two warriors and one is left handed he can guard the more exposed right flank of his partner and vice-versa. Alexander the Great had a whole cadre of left handed warriors who would take up the far right hand flank of his army (and I'd suspect this was probably fairly standard for ancient armies). The question then is really is there a strong enough difference in cooperation vs competition advantage from different-handedness for it to matter. This study doesn't seem to have addressed that question. At best it can be used like a prior to say "well, maybe it is that way since we DO have 10% lefties." I'm always a little suspicious of that sort of "Bayesian" kind of interpretation since it also leads to such absurdities as the notion that this generation will be the last one in history (do some reading on Bayesian Analysis, lol).

Re:As a lefty, just let me say (0)

Anonymous Coward | more than 2 years ago | (#39840045)

In a rank of men holding spears and shields, you absolutely want every one of them to be holding the spear in the same hand and the shield in the other. Spears all in right hands is fine. Spears all in left hands is equally good. One dude in the middle holding the spear the opposite way to everyone else is a huge weak point and fucks up the entire wall.

So there's that.

Re:That means we lefties (5, Interesting)

icebike (68054) | more than 2 years ago | (#39839623)

are like the wolves amongst you right-handed sheep, right!!!!???

I'm not ENTIRELY convinced, what about situations where it is advantageous for people to have opposite handedness for optimal cooperation? There seems to be a built-in assumption here that different-handed assortments of people will always have more problems working together. I'm not sure there's a practical way to test this as a general thing though.

I agree, the theory is weak.

Using sports as a model for why handed-ness exists is putting the cart before the horse. That Baseball was able to capitalize on left handed pitchers throwing to much more common right handed hitters is a rather late innovation in the annals of human endeavor.

Further, very few tools existed in historical times where handedness mattered at all. A wrench or a hammer or a spear have no handedness. Only much later were tools invented to meet the needs of the majority or users, which is why there was a tendency to put controls on power tools on the right.

The whole thesis mistakes cause for effect, suggesting tools and games we invented had something to do with what made us what we are. Whether our ancestors threw the spear, or picked the berry right or left handed couldn't have mattered at all.

Mod parent up. (2)

khasim (1285) | more than 2 years ago | (#39839991)

For this to have any relevance he'd have to show that handedness was somehow genetic (right-handed parents had right-handed children) or determined soon after birth and influenced by the parents (right-handed parents taught their children to be right-handed unconsciously).

Then those right-handed parents were more successful in the cooperative culture than the left-handed people.

Leading to more right-handed children than left-handed children.

But taking the already existing difference of left / right handedness and then using that to determine their "success" in a synthetic system such as sports ... that's just stupid!

There are no right-handed footballs. Either US or European.

Re:That means we lefties (0)

Anonymous Coward | more than 2 years ago | (#39839627)

That means we lefties are like the wolves amongst you right-handed sheep, right!!!!???

Then we almost-ambies are almost like huntsmen among wolves and sheep? To clarify: I am as good with my left hand as I am with my right, except for writing. Writing with the left hand feels "unnatural". In addition, I tend to slightly favor right hand over left hand when doing random simple stuff like picking up things, but not by a very large margin. Quite convenient for hand-tiring activities like bowling or clicking with a computer mouse all day or ... uh ... performing some other highly repetitive one-handed job.

I guess it is convenient to have a default choice for occasions when either one would be good if everyone did it. For example, when two cars approach each other on a road from opposite directions, always stopping for negotiating passingeach other would be cumbersome. That is why most countries have right-sided traffic.

Re:That means we lefties (1)

Hognoxious (631665) | more than 2 years ago | (#39839803)

For example, when two cars approach each other on a road from opposite directions, always stopping for negotiating passingeach other would be cumbersome. That is why most countries have right-sided traffic.

Bit of a non sequitur. Why does it matter which side it is, as long as it's consistent?

Re:That means we lefties (1)

Muros (1167213) | more than 2 years ago | (#39839663)

I'm having a little difficulty with the idea that cooperation required same-handedness to the degree that it largely influenced evolution in pre-literate societies. Tool use is cited; I have never seen an axe, hammer, knife or shovel that was not largely symetric in design.

The sports bit is interesting, but probably a red herring. Cooperative sports like football etc. were not played by professionals hundreds of years ago, and they didn't have every detail of the game worked out and practised beforehand. They just kicked the ball about. On the flip side, sports like boxing are cited as examples where being left-handed provides an advantage. I am going to assume the same would be true for a real blood and gore, swinging swords and spilling guts fight a thousand years ago. We know warfare has shaped genetic makeup; it is estimated that about 0.5% of all men in the world are direct patrilineal descendents of Genghis Khan. If left-handedness provides obvious advantages in something that has been an important evolutionary pressure for at least the past 100 generations, why then is it not more widespread?
I think we could be back to correlation vs causation here. I could be wrong, but I'm pretty sure I've read in the past that the left and right hemispheres of the brain are slightly different, and that whichever of them is dominant decides the handedness of the person (left hemisphere for right handed & vice versa). I would guess then, from my position of having no education whatsoever in psychology or biology, that the primary evolutionary pressures deciding for or against lefthandedness are mental in nature, and that things like possibly being better at boxing are merely a side effect.

Re:That means we lefties (1)

Hognoxious (631665) | more than 2 years ago | (#39839853)

Tool use is cited; I have never seen an axe, hammer, knife or shovel that was not largely symetric in design.

Some chefs' knives have an asymmetric profile. I have a left handed friend who can't cut straight with mine.

What about Golf !!! (2)

SpockLogic (1256972) | more than 2 years ago | (#39839399)

If this were true then golf would have a lot more left handers, but it doesn't.

Re:What about Golf !!! (0)

Anonymous Coward | more than 2 years ago | (#39839425)

Not really, because golf is an individual sport played against the course, not directly against an opponent, even in match play.

Also, high handicap golfers tend to slice (curve towards right for right-handers) while better golfers usually fight a tendency to hook (curve towards left for right-handers). Of course, left handers err in the opposite direction. I suspect that golf course architects would make an effort to even out the hazards as far as right side and left side are concerned.

Phil Michelson is an interesting case - he was born right-handed, but became a left handed golfer because he took lessons from his dad throughout his childhood and learned by mirroring his right-handed dad's swing on the left-handed side.

Re:What about Golf !!! (1)

bdabautcb (1040566) | more than 2 years ago | (#39839681)

I was going to make the same comment as the P.P. The article said that areas with individual competition should represent a higher number of lefties. Their analysis makes sense with baseball being higher than football, but the way their model is explained the most individual sports (golf, ping pong) should be the highest. Also, once at the professional level, course design is not much of a factor for left vs. right handed golfers.

Re:What about Golf !!! (0)

Anonymous Coward | more than 2 years ago | (#39839925)

But the cost of green fees and, especially, the cost of left-handed clubs are a factors. Golf, despite being fairly mainstream, still has significant barriers that prevent a young child from participating unless the parents are pushing the child into the sport. A left-handed child might not have access to left-handed clubs whereas a righted-handed child can always find used clubs. Other sports are fairly inexpensive to introduce to a young child. Baseball only requires a glove. Tennis racquets done really have handedness to them.

Re:What about Golf !!! (0)

Anonymous Coward | more than 2 years ago | (#39839837)

Match play is 100% against an opponent -- claiming otherwise is like saying tennis is played against the court.

Re:What about Golf !!! (1)

AK Marc (707885) | more than 2 years ago | (#39839959)

That's how I learned pool. I play leftie, as I was taught mirror of my grandfather. But as an adult, I've gotten more practice righty, so that I can switch for the shots that would be easy as a righty and very hard leftie.

Golf is slice-prone because instructors don't know how to teach it. A tiny amount of physics makes it simple. The shaft isn't centered. So the club face will always "open up" when the ball is struck. This directs the ball a little to the right and puts a spin on it that will have it curve further right. This is *easily* corrected by rotating the club head during impact. Over-rotation (speed) is hard for a beginner (though incorrect club facing is common). If the contact point was in-line with the shaft, there would be no tendency for slice/hook.

I followed Phil around Colonial when he won there a while back.

Re:What about Golf !!! (1)

Smekarn (1623831) | more than 2 years ago | (#39840029)

Golf is turn based, your point is moot.

The advantages of a lefty in individual competion comes from the righty's inability to quickly and properly react to the lefty's moves, having mostly had experience with competing against other righties. The lefty however, has also had most experience competing with righties, and will therefore not have the same drawback. Saying handedness would affect the outcome in golf is like saying it would affect the outcome of chess, or any other non-reactive type of competition.

the eyes have it (1)

ozduo (2043408) | more than 2 years ago | (#39839407)

Rt handed people who are Left eye dominant are usually more clumsy and less adept at sport than Left eyed Left handed people.

Re:the eyes have it (1)

icebike (68054) | more than 2 years ago | (#39839645)

And the reverse is also true, so If you had a point, I totally missed it.

Dear Hugh Pickens (2)

oldhack (1037484) | more than 2 years ago | (#39839411)

Stop posting these psychobabble.

Re:Dear Hugh Pickens (1)

Black Parrot (19622) | more than 2 years ago | (#39839517)

Stop posting these psychobabble.

The next one will explain why there are more innies than outies in capitalist societies.

Re:Dear Hugh Pickens (0)

Anonymous Coward | more than 2 years ago | (#39839543)

Dear oldhack,

(+5 Nail on the head)

Psychobabble... what a nice polite word for utter "horse shit".

Re:Dear Hugh Pickens (1)

cpu6502 (1960974) | more than 2 years ago | (#39839683)

You pickens what? Strawberries? Cotton? Dates?

Re:Dear Hugh Pickens (1)

owlnation (858981) | more than 2 years ago | (#39839733)

Yep, it's pure psychobabble. It's cart-after-the-horse bullshit.

Handedness has nothing to do with hands. It's whether the right or left brain is dominant. There are right brain dominant people who also happen to use their right hands, even though their left eye, or left foot is dominant.

Dear Hugh Pickens (-1, Redundant)

oldhack (1037484) | more than 2 years ago | (#39839413)

Stop posting pseudo science "studies".

In other news... (0)

Anonymous Coward | more than 2 years ago | (#39839417)

Lefties are combative assholes

Re:In other news... (0)

Anonymous Coward | more than 2 years ago | (#39839433)

ironically righties are trolls?

What tools? (1)

vlm (69642) | more than 2 years ago | (#39839431)

cooperation favors same-handedness—for sharing the same tools, for example

I'm struggling here to think of a primitive tool with handed-ness built into it. Anyone?

for example while physical competition favors the unusual. In a fight, for example, a left-hander would have the advantage in a right-handed world.

Doesn't know much about ancient warfare. Good luck running a phalanx or pretty much any massed swords -n- shields combat with some people randomly swapping sword and shield hands. Half your shield protects your buddy to the left, kinda like half of the shield of your buddy to the right partially protects you...

Of course if you're not one of those religious extremist types, the majority of human evolution happened long before ancient warfare kicked in; however, acting as a filter, most lefties would have died out due to the effects of ancient warfare.

Re:What tools? (3, Interesting)

The_mad_linguist (1019680) | more than 2 years ago | (#39839465)

Single bevel axes are 'handed'.

I imagine optimizing the grip would also cause some handedness as well.

Re:What tools? (2)

Black Parrot (19622) | more than 2 years ago | (#39839575)

Single bevel axes are 'handed'.

I imagine optimizing the grip would also cause some handedness as well.

How long ago did these first appear?

Re:What tools? (1)

CSMoran (1577071) | more than 2 years ago | (#39839471)

I'm struggling here to think of a primitive tool with handed-ness built into it. Anyone?

Shield.

Re:What tools? (1)

drkoemans (666135) | more than 2 years ago | (#39839537)

Phalanx = cooperation therefore, same handedness. Of course I didn't RTFA but I believe the author was referring to single combat and having a lefty advantage. Competition, not cooperation.

Re:What tools? (1)

cpu6502 (1960974) | more than 2 years ago | (#39839549)

>>>>> In a fight, for example, a left-hander would have the advantage in a right-handed world.
>>
>>Doesn't know much about ancient warfare. Good luck running a phalanx

In a competitive species the phalanx wouldn't even exist, because the humans would not cooperate with one another. Thus there'd be no need disadvantage to being either right or left, and the genes would be split evenly 50-50.

Re:What tools? (1)

VinylRecords (1292374) | more than 2 years ago | (#39839587)

I'm struggling here to think of a primitive tool with handed-ness built into it. Anyone?

Not exactly primitive but everything in ancient Roman and Greek culture was built around everyone being right handed. Even the language reflected the value of being right handed compared to being left handed. They would slap students' left hands, even the great Caesars, to get them to learn to be right hand dominant.

The Latin (Roman) word for 'right' was 'dexter'. It's where we get the words dexterity, dextrous, and ambidextrous from. So in English someone being 'ambidextrous' means that they have two right hands. And the Latin word for 'left' was 'sinistra'. Which is where we get the words sinister and ambisinister. So someone who is ambisinistrous is someone with two left hands is considered unskilled manually.

In primitive cultures you'd see hand dominance as well. It was innate and the culture was designed around right handed dominance. While technically the tools that they used could be done with either hand, the information how to use those tools were passed down by demonstration, and the demonstrations were usually done by a right handed person. So a human from thousands of years ago hunting with spears and rocks would always throw those weapons with his right hand, and show his son to do it with the right hand, and so on. Sure those rocks aren't designed to be thrown with a specific hand but our natural tendency to be right handed influenced our primitive ancestors to continually practice right hand dominance.

Re:What tools? (1)

vlm (69642) | more than 2 years ago | (#39839687)

OK the greek and roman stuff happened well after 99.999% of human evolution had ironed out all that stuff. They're a lot closer to me than my ancestor 200K yrs ago (or whatever) back when we selected for handedness.

BTW the sinistra business is all about shaking your fren-imes hand with the right hand, holding real tight so he can't get away, then stabbing him in the gut with a dagger held in the left hand.

The monkey-see monkey-do thing is relevant to the pre-historical era. That is a good argument. That gave me an excellent idea of take dead animal carcass flop it on ground hold skinning knife you must point the head the same direction each time, at least that's my experience with cleaning fish. You'd think a CAD kind of guy would be able to gut a fish equally well with its head to the left or right but peculiarly even I always hold with left hand and cut away from my hand which has a certain way of fixing the carcass position. I think the kids could get the general idea of spear chucking in either hand, but animal skinning training is going to have an inherent handed-ness that is going to otherwise confuse the hell out of both kid and adult if you try to flip the mental picture and suddenly the lungs are over here and the guts are over there instead of their "normal" position, or you have to use really weird hand grip positions to properly skin.

Re:What tools? (1)

starfishsystems (834319) | more than 2 years ago | (#39839801)

I'm struggling here to think of a primitive tool with handed-ness built into it. Anyone?

Any kind of axe or hammer or adze whose haft is made from a found object such as tree branch would qualify.

Such hafts are never perfectly symmetrical, and they are held asymmetrically. A good tool will exploit the natural shape of the haft so as to conform to the user's handedness. The center of effort of the tool as well as the attack angle of the blade will be set accordingly. It's usually obvious in the instant that you pick up such a tool whether it's made for left-handed or right-handed use.

Sorry! (0)

Anonymous Coward | more than 2 years ago | (#39839489)

I just couldn't get past the error on page1, paragraph 4.

Well, no... (1)

joh (27088) | more than 2 years ago | (#39839493)

In a perfect world we would all be ambidextrous -- being able to use BOTH hands would make things much simpler.

Re:Well, no... (4, Funny)

Black Parrot (19622) | more than 2 years ago | (#39839527)

In a perfect world we would all be ambidextrous -- being able to use BOTH hands would make things much simpler.

Yeah, one could take over when the other got tired.

Re:Well, no... (0)

Anonymous Coward | more than 2 years ago | (#39839693)

I have to use both hands at the same time. One to hold the magazine down, the other to peal the sticky pages apart.

Re:Well, no... (3, Interesting)

Frequency Domain (601421) | more than 2 years ago | (#39839813)

You joke, but that was literally true for me w/ regards to handwriting. Then one day my second grade teacher saw me switching hands and freaked out. She made me sit on my left hand for the rest of the year and had the colossal gall to tell me that someday I'd thank her for it. When my doctor learned about it at my next annual physical, he was pissed off beyond belief. He didn't cuss, but he kept muttering about "superstitious morons" and "subjecting kids to the prejudices of idiots", or words to that effect.

Fortunately the only thing impacted was my handwriting. Fifty years later my left-handed writing still looks like a first-grader while my right-handed writing got arrested at a second grade level. But I'm one heck of a typist, when I played soccer I did equally well on either left or right wing, I'm popular at dinner parties because I can accommodate whoever I am seated next to without bumping elbows, and my wife thinks I'm a very versatile fellow.

Re:Well, no... (1)

FrootLoops (1817694) | more than 2 years ago | (#39840005)

According to this study [springerlink.com] ,

Homosexual men had 82% greater odds of being non–right-handed than heterosexual men

I guess we learn to use both at once ;)

Re:Well, no... (1)

tdarklighter (247845) | more than 2 years ago | (#39839761)

It wasn't difficult to train myself to use my left hand for certain tasks. For example, after half a day I can easily use my left hand for the mouse (buttons flipped or not) and use my right hand for a pen. Also, when I first picked up a guitar 20 years ago it seemed like it would have been easier to fret with my right hand but after enough hours I gained dexterity in my left.

I've followed these studies forever... (3, Informative)

smoothnorman (1670542) | more than 2 years ago | (#39839499)

Just a few years ago, a Canadian study using baseball stats (because they tracked handiness closely) concluded that lefties were far more likely to die, ( http://www.nejm.org/doi/full/10.1056/NEJM199110033251412 [nejm.org] ) this was later shown to have suffered a seemingly paradoxical sampling error (not controlling adequately for those that didn't die). Then there was another study that concluded that left-handedness was likely the result of anoxia in the womb ( http://www.sciencedirect.com/science/article/pii/002839327390050X [sciencedirect.com] ). It was discounted for similar sampling error problems. Neurological "wiring error"; perhaps a mutation with few consequences; advantages in the mathematical world (presumably via having a screwy mindset); Language disadvantages; Language *advantages*; high proportion of left-handed (possibly suppressed) American presidents http://www.anythingleft-handed.co.uk/presidents.html [anythingle...nded.co.uk] (Clinton, Bush, Obama ... ). So... run a elaborate predator/prey model applied to sports and see an advantage for the 10% that are different; sounds like rediscovery of Perato distribution to me, http://en.wikipedia.org/wiki/Pareto_distribution [wikipedia.org] I'm just not convinced that there's been a proper scientific approach to this issue to date, and until then i'm still stuck with a twisted spine in most college classrooms.

Re:I've followed these studies forever... (1)

cpu6502 (1960974) | more than 2 years ago | (#39839579)

>>>high proportion of left-handed American presidents

Politicians are pretty competitive. They don't like to cooperate with others, which may be why they joined that career (a desire to control other humans' stupid decisions).

Re:I've followed these studies forever... (0)

Anonymous Coward | more than 2 years ago | (#39839715)

Yeah, that is probably my bad, I never realized the left-handed desks were for left handed people. I always used them, despite my righty-ness, because I found them more comfortable as I could swing my arm around in the free air all I wanted.

Mov't and Left/Right Hemispheres (0)

Anonymous Coward | more than 2 years ago | (#39839513)

Read Robert Ornstein - The Right Mind.
Also, they need to realize that sports are spacial, and hemispheres tend to have distinct roles in visual and spatial capacities. Pattern recognition plays a role as well.

Golfers? (0)

Anonymous Coward | more than 2 years ago | (#39839539)

From TFA: "On the other hand, the number of successful left-handed PGA golfers is very low, only 4 percent. The model also accurately predicted this."

Eh? Golf is a sport where there is no cooperation and where being differently handed should have no benefit in competition with others. One would think that golfers would have the same number of lefties as the general population.

Methinks that cooperation/competition explains part of the situation, it doesn't explain everything.

Utter nonsense (1)

BonzaiThePenguin (2528980) | more than 2 years ago | (#39839551)

You can pick who is on your football team, but you can't pick who is in your society. And cooperation stems from empathy, not handedness.

Re:Utter nonsense (1)

wonkey_monkey (2592601) | more than 2 years ago | (#39839897)

You can pick who is on your football team, but you can't pick who is in your society.

Nice soundbite, but what does it have to do with anything? Society has evolved to have this proportion of lefties and righties because it strikes a successful balance. So no, you can't pick who's in your society, but you don't have to because evolution has already selected for a 90/10 balance. Survival of the fittest football team in one case, survival of the fittest tribe in the other.

And cooperation stems from empathy, not handedness.

Is anyone suggesting cooperation stems from handedness? If anything, the summary suggests the opposite.

Still, kudos for summarising your post in its title.

No, hockey teams can't be same-handed (0)

Anonymous Coward | more than 2 years ago | (#39839555)

A hockey team needs a good mix of left- and right-handed players. Summary is complete horse-hockey.

TFA even pretty much clearly spells it out in table S1.

Probably a simpler answer (0)

Anonymous Coward | more than 2 years ago | (#39839565)

Handedness is most likely related to which neural network gain fine grained control solutions first. The "preference" we experience may just be the recognition of this better control.

Rubbish (0)

Anonymous Coward | more than 2 years ago | (#39839659)

This is so much crap on so many levels, I can't even begin to enumerate. Half of these blogs shouldn't even be allowed to exist.

left-handedness is a choice (1)

j0rbshua (2587187) | more than 2 years ago | (#39839815)

and how does this explain the fact that the only thing I do left handed is write with pen/pencil. i'm fairly ambidextrous in a variety of sports but i'm right hand dominant, except for handwriting.

That's a lot (1)

nervouk (902685) | more than 2 years ago | (#39839823)

"Representing only 10 percent of the general human population, scientists have long wondered why left-handed people are a rarity." 10% of the population are scientists?

Only 10 percent (5, Funny)

starfishsystems (834319) | more than 2 years ago | (#39839829)

FTA:
Representing only 10 percent of the general human population, scientists have long wondered why left-handed people are a rarity.

Wow, I never knew that scientists made up ten percent of the population. Yay us.

Is handedess a real thing? (1)

justin12345 (846440) | more than 2 years ago | (#39839849)

If a child learned to type before they learned to write, would they ever consider which "handed" they are?

I'm left handed, but aside from handling pens (which these days don't do on a daily basis) I do pretty much everything with both hands equally. When I was a kid alot of todo was made of getting me a left handed baseball glove, left handed scissors, and even a left handed violin. None of those things were very useful. I can catch, cut, play, even shoot with both hands, more or less evenly. (I actually favor my right hand when shooting.)

Most left handed people I know say the same thing. I'm just guessing, but I'd imagine that a lot of right-handed people are more ambidextrous then they know, but unlike lefties they've never had to think about it.

With writing, handedness makes a huge difference. It's not a simple matter of inversion, forming a letter left-handed is completely different. There is a great deal of "muscle memory" that comes into play. But imagine a generation that grows up typing instead of writing. Would they ever know which handed they are?

Re:Is handedess a real thing? (1)

madpansy (1410973) | more than 2 years ago | (#39839965)

Playing piano forces you to use both hands simultaneously. As a righty, it is a challenge for me to get the same amount of control from my left that I get from my right. No matter how much I practice with my left hand individually, I still don't feel the same power as I do from my right. This could be because most piano music has the left hand simply keeping rhythm while the right must be more expressive, leading with the melody.

I don't mean to be crude . . . (2)

NicknamesAreStupid (1040118) | more than 2 years ago | (#39839909)

. . . but before there were organized sports, people had to deal with certain personal matters. They also had to physically interact. As one once said, "I don't eat where I shit." Of course, you might argue that, "One hand washes the other." That is true, but every shithole did not come with Purel, a bidet, or even water. There are other practical reasons for using one hand for one thing and the other for something else.

Frankly, I doubt if being left-handed or right-handed is genetic. Perhaps it is hereditary in the sense that you learn from birth based on how others use their hands, and it would be easy to use such behavior to perpetuate a trend. For example, everyone born in a Mandarin-speaking village begins to speak Mandarin without any formal training. Or most people use their hands to eat instead of their feet, which anyone born without hands can tell you is quite doable.

As others have pointed out, society can use commonalities to its advantage, which would re-enforce such trends.

BTW, I typed this with both hands.

For hockey... (1)

addie (470476) | more than 2 years ago | (#39839973)

The idea that it's beneficial for every player on a hockey team to be same-handed shows quite an ignorance of the game. There is a left-wing position and a right-wing, and being able to either protect the puck from a defender, and/or have the best possible angle to shoot on net, depends very much on whether the player shoots left or right. This is further complicated by players who choose to shoot left despite being right-handed (see this blog post here [darrenbarefoot.com] , I couldn't find a better source)

The results of the study are interesting, and make somewhat intuitive sense, but they should be careful not to generalize to too great a degree.

Meh (1)

slasho81 (455509) | more than 2 years ago | (#39839975)

I haven't RTFA (obviously), but it sounds like those fellas hammered a model onto a data set and attached a nice simplistic explanation on top of it.

The reason many lefties excel in some sports is due to the element of surprise their left-handedness gives them. Finding a simple formula to determine lefties percentage depending on some arbitrary criteria of cooperation/competition, which is an enormously complex subject in itself, sounds like complete nonsense.

Load More Comments
Slashdot Login

Need an Account?

Forgot your password?