Question: how come left handed people are rarer than right handers?

Lydia Bach answered on 17 Nov 2014:

Hiya,

Only about 10% of people are left handed, and thats because of influences from the environment and because of genes. They found that left handed people have more left handed family members, and that brains of left handed and right handed people are wired quite differently! They are still in the process of finding out what genes could be responsible for the difference, but apparently genes are that make people right handed are more common.
The same applies for animals too! Crabs for example tend to have their larger crusher claw on the right and the smaller on the left! This is because of genetics.
They think it has to do with how the two different brain hemispheres split up their labour. Scientists think that one brain half could probably be better at fine skills than splitting them up.
So people who use their right hand more, use their left brain more – the left brain half is responsible for handiwork, so thats probably what they would be strong at in real life. Those people who use the left hand and right brain might be better at speaking and creativity.