Bill Gates. Marie Curie. Oprah Winfrey. Leonardo da Vinci. What do these famous folks all have in common? They're left-handed. 
Left-Handed Girl
Credit: VOISIN/PHANIE/Getty Images

For a long time, scientists have debated why some people are left-handed. Formerly, people thought our hand orientation depended on genetic differences in our brain, but recent research seems to indicate that our preference actually stems from our spinal cord.

"The research — by Sebastian Ocklenburg, Judith Schmitz, and Onur Gunturkun from Ruhr University Bochum, along with other colleagues from the Netherlands and South Africa — found that gene activity in the spinal cord was asymmetrical in the womb and could be what causes a person to be left- or right-handed," explains an article by Lindsay Dodgson on Business Insider, citing research from a study published in the journal eLife in 2017.

Based on their research, the scientists found that a growing fetus already determined right- or left-handed preference before the motor cortex — which controls motion — and the spinal cord are connected. This means a baby is already selecting their go-to hand before the brain is sophisticated enough to create movement in the body.

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Well, time to share this fascinating intel with all the lefties in our lives — before we celebrate them tonight by giving them the coveted corner seat at the dinner table to avoid those awkward elbow-bumping moments.