You asked us, why do we use one hand more than the other? By the age of 2 or 3, most of us have started to prefer using one hand, typically the right.
Only about 10 percent of us end up as southpaws - basically all of the evil, witchy, criminal-type people out there. Just kidding! I'm just trying to mess with you, because we don't believe in that crazy talk anymore.
But why do we develop into righties and lefties? That question has more than a few scientists scratching their heads, with their dominant hand of course. (It's going to get worse.)
Handedness in humans probably goes way back, maybe as far as our Neanderthal ancestors or even earlier. Some researchers suggest the trait evolved as our tools became more sophisticated.
But why the right hand came to dominate the left is anybody's guess, although we do know that genetics plays a role in handedness and that it's possible hundreds of genes are involved.
But, a person's environment is important too, just ask your grandma. In the past, lefties often had to learn how to write with their favored hand tied behind their back, and even today, we basically live in a right-handed world, forcing many a lefty's hand when it comes to using scissors, writing at a desk or even zipping up a jacket.
Until, that is, you get a lefty into the boxing ring or at home plate, when an element of surprise gives them the upper hand.