The mystery of why left-handers are so much rarer

Relatively few people are lefties, and it’s a puzzle why. Still, the science of handedness is revealing fascinating insights about you – from how it could change the way you think, to the fact that you might be ‘left-eared’.

 .. Overall 40% of us are left-eared, 30% are left-eyed and 20% are left-footed.But when it comes to handedness, only 10% of people are lefties.

Why could this be? Why are left-handers in the minority?

.. But when primatologists study chimpanzees in the wild, their patterns of handedness look very different to ours. For each task around 50% are right-handed, and 50% left. So where in our evolutionary tree does this 1 in 10 ratio emerge?

.. We know that left- and right-handedness has a genetic origin. However, geneticists are still trying to pinpoint which bits of DNA are involved, and there may well be up to 40 different genes at play.

.. “My personal hunch is that left-handers are both more talented, and suffer deficits. If you are left-handed you might find yourself with a slightly unusual way your brain is organised and suddenly that gives you skills that other people don’t have.”

.. It’s true, she says, that when you look at rare conditions, like Down Syndrome, epilepsy and cerebral palsy, the ratio of left- to right-handers is more like 50:50 rather than 1:10.

.. He found that nine out of 10 foetuses preferred sucking their right thumb