What Makes Some of Us Left-Handed?

What Makes Some of Us Left-Handed? For all its sophistication, modern science is still unable to explain exactly why some of us prefer to do these tasks with the left hand and some with the right. Many theories are proposed and debated. http://ow.ly/sNe030j8JfY

What Makes Some of Us Left-Handed? Hint: Nobody Knows

In "On the Other Hand," the neuroscientist Howard I. Kushner (a lefty himself) offers a short but meaty survey of the science, sociology, and enduring mysteries of handedness. Dr. Abigail Zuger reviews it for Undark.
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