As handedness is a highly heritable trait associated with various medical conditions, and because many of these conditions could have presented a Darwinian fitness challenge in ancestral populations, this indicates left-handedness may have previously been rarer than it currently is, due to natural selection.
Why is being left-handed more rare?
In fact, one of the more unusual hypotheses to explain the rarity of left-handedness is that a genetic mutation in our distant past caused the language centres of the human brain to shift to the left hemisphere, effectively causing right-handedness to dominate, Alasdair Wilkins explains for io9 back in 2011.
Do left handers have better memory?
Lefties--or at least relatives of lefties--may be better than right-handed people at remembering events, according to a new study. Since the mid-1980s, scientists have known that the two brain hemispheres of left-handers are more strongly connected than those of right-handers.
Is left-handed lucky?
Left-handers or lefties are often considered unlucky in many cultures, including the Indian culture. We are told to accept prasad with our right hands only, and this hand is preferred for all our rituals, tilak, yagna, etc.