Which hand do you instinctively catch or grab with?
Right; but I’m sure that I track it with my left eye.
Both kinds–weapons and photography. I notice which fellow photographers are right-eye shooters and which are left-eye shooters. And it doesn’t seem to be correlated with handedness, so far as I can tell. Every so often I try switching to my left eye on the viewfinder to shoot, and it just feels weird and unnatural. In my experience, the split in left-eye vs right-eye dominance (at least as observed by how photographers look through their cameras), is about 2:1 in favor of the right eye, so much more prevalent than left handedness.
The Straight Dope on handedness in animals (at least, cats). Which also supports what I and Mach Tuck were saying about a dominant hand leading to greater dexterity.
I’ve never heard of forcing one to use a right hand making them dyslexic. 
I was kind of coached to use my right. I drew a lot…I donno. My school was very into penmanship. I have two leftie brothers and one rightie. My son is a leftie and is an art freak.
My mom said I used both until first grade or so. My fine motor skills re: writing were better with my right hand, but sewing, chalkboard, everyday tasks I could do with either until I had a TMI.
Now I’m just klutzy everywhere!
(Can totally wiggle my big toe side to side, though…I think that’s rare.)
a friend of mine who golfs a lot (and studies the game) commented that there are a lot more Canadian golfers who swing left-handed than there are American golfers who swing left-handed.
One theory to explain it is that Canadians are more likely to play hockey growing up than Americans, and every hockey team needs players who can shoot left-handed, to be the left wingers and the left defencemen. That in turn may make it easier for Canadians with hockey experience to golf left-handed. Interesting theory, but I don’t know if it’s backed up by any real evidence.
Previous thread on the issue: Ambi Dopers: which hand do you use? Introduced me to the term “cross-dominant”, which is apparently more common than true ambidexterity. The idea of cross-dominance is that some people use one hand for some things, and the other hand for other things.
The cooking example I gave in the OP of that thread matches Mach Tuck’s snowball example. I often have to stop and think which hand to use for certain tasks, even though I’ve done them many times before. That slows down my reaction time.
But the idea of cross dominant explains other things in my cooking. I always use my left hand to peel the carrots and potatoes, and then use my right hand to cut them up. Doing it any other way just feels weird.
Another thing that I think is related is that the whole idea of “left” and “right” isn’t automatic to me. If I’m driving and a passenger tells me to “turn right at the next corner”, I’m going to have to stop and think, “which is right?” It used to frustrate Mrs Piper a lot, until we figured it out. Now, if she’s giving directions, she’ll say “your side” for left, and “my side” for right, which I can react to much more quickly. (Even typing it out just now, I had to stop and think which side meant “left” and which side meant “right.”)
I’m unsure if this counts as “real evidence,” but when I played hockey, I shot left. I don’t know why, but my Dad (a right-hander), who taught me (also a right-hander) hockey when I was very small, taught me to shoot left. So, as a hockey player, I shot left.
Today, as a golfer, I shoot right. No idea why, given my hockey background. But offer me a hockey stick, and I’ll ask for a left-handed one. Offer me a golf club, and I’ll need a right-handed one. Curious.
Interestingly, a right-handed golf buddy of mine hits left. He has no idea why. I’ll try to remember and ask him.
I always figured most western civilization’s language is written from left to right, so being right handed is arguably more natural to write; therefore stronger enforcement from teachers (and nuns) to encourage switching leftys to rightys.
I know had things been the other way around, I would’ve been extremely frustrated.
I’ve injured my right hand a couple of times and couldn’t use it for a while. Buttoning a shirt or zipping your pants can be more difficult than you might think.
Easily disprovable from East Asians, at least. Things were written in columns from top to bottom, right to left, but it was still bad luck to be left handed and forced switching was the norm for naturally left handed children.
I’m left-handed. My father always claimed that it was all my mother’s fault because my mother sat to my left at the table and when she handed me a spoon I’d grab it with my nearest hand. My father claimed a number of other dumb things.
I’m just more comfortable using my left hand. I learned to shoot a shotgun right-handed, though, because the ejection mechanism of a normal single-shot shotgun is nearly impossible to work left-handed (unless you like shell casings ejecting into your face). I also learned to play the guitar right-handed in college because the guitars I borrowed from my fellow college students were strung for right-handers.
I think “incomplete dominance” also applies to me. I write right-handed, but do almost everything else left-handed. I’m also left-eyed and a left-footed kicker. My handwriting sucks no matter which hand I use, I’m betting it’s connected somehow.
There’s lots of leftys in my family, and I have an uncle who was forced to switch by a teacher who didn’t want to teach a left-handed kid how to write. He has all sorts of problems with fine motor skills, and his handwriting also sucks.
I’ve had people ask me if I was forced to learn to write right-handed. I really doubt this was the case, I don’t think my mom would’ve allowed it after seeing what it did to her brother.
Motor dominance is related to brain lateralization. We still don’t really know why certain functions are usually lateralized. Brain plasticity makes it possible to relocate specialized brain functions. Young children with traumatic injury to Broca’s area, for example, typically don’t have huge problems with speech in the long term, but most adults will have impairment with damage to that same area.
I say “most” because not all people have language functions mapped to the same areas. The chance of having some or all of your language functions located elsewhere is much higher for left handed than right handed people. Similarly, lefties show more mixed body dominance and some apparent differences in processing and creativity, especially in language.
Left handedness tends to be much more prevalent in violent cultures than the average in more peaceful areas, which most scientists think is because it provides a competitive advantage in fighting. More lefties survive, so the proportion of lefties goes up. Handedness appears to be partially inheritable too.
Anecdotally, I can provide some support for the competitive advantage. I’ve done several different styles of martial arts and related sports, and it’s a serious surprise when you either fight left handed to start, or can easily switch sides. Righties get used to fighting righties since lefties are relatively rare. Lefties get used to fighting righties, so they have an automatic advantage relative to right handed people since they don’t have to change their conditioned responses, and they also have a surprise advantage. In a fight, sometimes all you need is a couple of seconds of surprise or some awkwardness in motor response.
I was never under the impression that eye dominance was linked with hand dominance. I know my left eye is dominant, but I am notoriously worse that most righties when using my left hand for anything.
(I have astigmatism in both eyes, but my body adapted to my left eye, not my right. I close my right eye, and everything looks the same. I close my left eye, and it’s like looking through a fisheye lens.)
The same thing happens in the less violent sports. The most awkward raquetball match that I ever played in was one where I (a left-hander) played another fellow who was also left-handed. Neither one of us knew where to hit the ball toward the other guy’s weak spots.
Whereas “sinister” comes from a root meaning “left-handed”. Because as we all know, southpaws are of the Devil.
I’m a lefty myself, but AFAIK I’m the only one in my entire extended family. Parents, grandparents, great-grandparents (the ones I knew at any rate), uncles and aunts, cousins - all right handers. If it’s hereditary, it takes the long way around.
Guess in this long line there’s been some real strange genes ; I got 'em all, I got 'em all with some extras thrown in 
I was “turned” in nursery school. They did a good job because I consider myself right-handed. But my pencil grip is crazy (my penmanship is legible but not very pretty). Even though I use my right hand more than my left, my left arm and left hand are significantly longer, larger, and much stronger than my right is. I tend to lean towards the left, though I keep my head cocked to the right. I should probably just train myself to do things with my left and see how well I do.
Eyedness, earedness, handedness and footedness are “supposed” to all be on the same side, but it seems that it’s not uncommon for them to be mismatched. I’m left-eyed, left-eared, and mixed-footed (I rest on my left leg, reflexively support myself with my left foot when I stumble, take my first step with my left foot, but I kick with my right and my toes are more flexible on this foot. My balance is also a dash better on this foot). I do stammer sometimes, and I’m a major clutz with my gross motor movements. But I never thought my cross-dominance was to blame.
Not only can handedness be genetic, but it can be environmental as well, resulting from factors occurring in the womb. Interestingly, there are a disproportionate number of left-handed people with mental retardation AND genius-level IQs. Left- and mixed-handedness is also associated with higher incidences of neurological problems (such as autism and schizophrenia). More males are lefty than females. So sumpin’s going on with that whole lateralization thing.
It should also be noted that the nature of certain tasks influences this too. For example, I don’t have statistics, but I believe that most right handed people will execute a running long jump with their left foot. I’m not certain why this is, but I would hypothesize it’s because such people probably kick objects with their right foot, and so are used to planting their left.
A note on why I’m so interested in these issues…
At one time I was a professional juggler / unicyclist. Many people think jugglers are equally adept with both hands, but in my experience it’s not true. We of course use both sides for many juggling moves, and you have to work hard to get your non-dominant side up to snuff for many skills. But I, and every colleague I can remember, have very firmly developed dominant sides. An observer can easily think we’re “ambidextrous” because we try to make things look smooth and easy when performing, but remember those are intensively rehearsed skills.
Anyway, I’m right handed and right footed for almost everything, with one major exception - I’m left footed on a unicycle. I think it’s due to the same issue as the foot plant for a long jump, in that I’m used to supporting my weight with my left foot because of kicking with my right. That said, most right handers I know are right footed on their unicycles, so I may be a little unusual there.
After that career I became a teacher / coach and studied a lot of anatomy, physiology, biomechanics and sport psychology. Still later I became a pilot and flight instructor, and I’ve become very interested in cockpit ergonomics and flight control layout for left and right handers. But that’s another discussion.