My oddball left hand

I am left-handed. According to popular statistical belief only 7-10% of people are left-handed and being left-handed is more prevalent in males than females (and even more prevalent in people with neurological disorders. Nice.)

What surprises me the most is why there are *ANY* left-handed people left in the world today. Think about it. As best that can be determined left-handedness is not more or less prevalent now than any time in the past. If only 10% of humans show a particular trait usually that trait will disappear over time, if you believe in natural selection. So I wonder why we're still here. What function do we lefties serve that requires our continuance in the world?

My particular case is stranger yet. My right eye (shooting, archery) is dominant so I shoot or use a bow-and-arrow with my right hand. I'm left-handed (writing, throwing, batting) but one could argue that I stuck so completely at hitting a baseball perhaps I am really a switch-hitter with no advantage shown in either stance. I'm joking in case you couldn't tell, but I do suck at baseball. All I can say to that is batting left-handed "feels" natural while batting right handed does not.

When it comes to footwork (soccer, punting a football) I'm right footed. Guess I'm just a freak of sorts.

What got me thinking about this was the fact that I use a mouse right-handed only. I can only wonder if I trained myself this way having had to deal with mice that were designed to work with right-handed people (the early mice, not the ones we have today). Grabbing a mouse and using one with my left hand just feels.. wrong. In fact I can't do much of anything correctly with a mouse in my left hand yet I can use a mouse to draw free-hand with my right. The mouse is also a first-generation invention. My father learned to use the mouse at exactly the same time I did thus providing neither an advantage of habit formed over time. Ironically we both use a mouse right-handed.

Replace a mouse with a digital pen and I'm back to left-handed again.

Still, I wonder. Why am I left-handed? My father is a lefty. Did I inherit that from him or did I learn to be left-handed by imitating how I saw him operate? If almost 90% of the people of the world are right-handed why isn't everybody?