Why Are Some People Left-Handed?

We've got two perfectly good hands attached to two perfectly good arms, so why do most people prefer to use one over the other for common tasks? Viewers like you help make PBS (Thank you 😃) . Support your local PBS Member Station here: https://to.pbs.org/PBSDSDonate Subscribe to It's Okay To Be Smart: http://bit.ly/iotbs_sub David Wolman's "A Left Hand Turn Around the World" http://amzn.to/1wYqOS2 (lots more references in there!) Chris McManus' "Right Hand, Left Hand" http://amzn.to/1umztyL The best collection of the science of handedness on the internet: Right, Left, Right, Wrong - http://www.rightleftrightwrong.com/in... Genetic link between handedness and body asymmetry: http://www.plosgenetics.org/article/i... A gene associated with handedness and schizophrenia: http://www.nature.com/mp/journal/v12/... Genetic theories of handedness: http://www.rightleftrightwrong.com/th... Produced for PBS Digital Studios Joe Hanson - Host and writer Joe Nicolosi - Director Amanda Fox - Producer, Spotzen IncKate Eads - Associate Producer Katie Graham - Director of Photography Andrew Matthews - Editing/Motion Graphics Dalton Allen - Post-production intern John Knudsen - Gaffer Theme music: "Ouroboros" by Kevin MacLeod Stock images via Shutterstock ----------- Join us on Patreon!   / itsokaytobesmart   Twitter   / drjoehanson     / okaytobesmart   Instagram   / drjoehanson     / okaytobesmart   Merch https://store.dftba.com/collections/i... Facebook   / itsokaytobesmartpbs