A LEFT-HAND TURN AROUND THE WORLD

Science journalist Wolman offers a spirited defense of left-handedness, which he takes to be one more sign of the wondrous diversity of nature.

Sinister, gauche, leftist: What’s a self-respecting southpaw to do in the face of so much semantic freight, and the world’s misunderstanding generally? Well, writes Wolman, it’s not necessarily true that all southpaws are born curve-ball pitchers, but the 10–12 percent of humans who are left-handed are interestingly different—“not starkly different…but not trivial in their differences either”—from their right-handed peers. The left and right sides of the human brain are separate, bridged by the corpus callosum, which passes information between the two halves. Yet, early science to the contrary, right-handers don’t do all their thinking on the left side and lefties on the right; there’s a lot more to it than that, even if Wolman favors a gods-for-clods approach, for beyond the two facts that the brain halves are distinct and joined by the corpus callosum, he writes, “there’s no need to be weighed down with more brainy lingo.” Aspiring brain surgeons need not fear, however: Even though written at a lay-accessible level, Wolman’s narrative is robust, treating all kinds of conjectures as to what causes the distinction between right and left—likely, in the end, some little evolutionary jog that permits lots of asymmetry in a species that prizes the adaptive advantages of symmetry, such as having two legs and two eyes that are more or less equal. Happily for lefties, who are “cool because they allow you to un-confound two hypotheses,” there’s no evidence that handedness relates to intelligence or ability, or that lefties are bewitched or weird or doomed, or that all those other prejudices of yore have any foundation.

A nicely balanced blend of pop science and personal essay, and just the thing for the family southpaw.