Dad was a Southpaw. Mom was a Righty.
I’m right handed BUT left eye dominant (unusual....most have the same hand/eye dominance). The result is I shoot pool or shoot a rifle and eat Left handed. I can also write just as neatly - though more slowly - with my left hand. I absolutely can not throw left handed though.
There’s clearly a spectrum for hand dominance with some skewing far less to just one side than others do.
Reading can go any old way, although most of us are used to left-to-right, top-to-bottom. Vertically written text winds up read right-to-left, top-to-bottom when turned clockwise, if written by right-handers. Horizontally written text is, well, what we have today. Literacy is probably a large reason for recent cultural dominance of righthandedness, but again, not a good explanation for its antiquity. Handed-ness just *is*, and as the article alludes, arises apparently out of four spots in the genome that happen to all arrive in the same zygote at the same time. :^)