Right Hand, Left Hand?
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We have two hands, but why do most people only use their right hand for writing and other difficult activities? We do not know for sure, but the most likely explanation is that we get it from our parents. The genes that decide handedness, however, are still unknown. It could be caused by two genes, or even just one.
It is possible that our tendency for right-handedness goes back to early human history. Women would have held their babies to their left side because of the calming sound of the mother's heartbeat. This left the right hand free to do other things, and have greater skill as a result. This tendency could then have been passed down in human genes.
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