Scientists discover connection between left-handedness and neurological disorders. Study reveals lefties have 3.5 times higher autism risk, pointing to shared genetic and developmental factors.

Bill Clinton, another recent left-handed U.S. president, holds a pen in his left hand after signing the North American Free Trade Agreement, at the Mellon Auditorium in Washington, D.C. in 1993.

Thus, left-pawedness in dogs is about three to four times as likely to occur as left-handedness in humans. (For more on pawedness in dogs, see my detailed post here.) Turtles show “flipperedness.” ...

The widespread belief that left-handers—who make up roughly 10 percent of the population—are more imaginative or artistically gifted has persisted in part due to the brain's structure.