Why is 10 to 12 percent of the human population left-handed? David Wolman, part of that minority, took a year to research the origins and consequences of being a southpaw. His research took him, literally, around the world.
His first stop was a museum in Paris to view Broca's brain, the granddaddy of all brain research. From there his tour included a castle in Scotland, supposedly belonging to a left-handed clan (they weren't all really left-handed). He visited neuroscientists in Berkeley and monkey researchers in Atlanta (the latter record the number of instances the monkeys throw excrement right- or left-handed). He took a week-long palm-reading course in Quebec to see if there were significant differences in the palms depending on handedness (the palm readers told him that you can change the lines on your palms by changing your attitude!). He spoke with psychologists in London and an amputee in Illinois. In Japan, he played in a Lefties golf tournament.
He discusses the theory of handedness as a scale from strong right-handedness to strong left-handedness and everything in between. Mixed-handers do certain tasks with specific hands: writing, eating, brushing teeth, throwing, opening doors, etc. He explains how people with strong handedness (right or left) may be more alike than they are to mixed-handed individuals. He talks about how brain wiring differs between righties and lefties.
There is science. There is humor. There's some wonderful trivia. My favorite: 90 percent of parrots favor their left.
So, why is 10 to 12 percent of the human population left-handed? Dunno, still. Itís fun pursuing the answer though, no matter how elusive it is. This book would make an informative gift for any lefty you know.