Left-Handed Leftovers

August 13th is the 22nd Annual Left Handers Day, and as a proud lefty I thought I would share a collection of lefty related links.

First up, an article on the Origins of Handedness, which informs us that only 15% of humans are left handed, oddly enough two-thirds of lefties are born to right handed couples. The proportion of lefties is even lower in China, where less than 1% of students are lefties, and even lower behind home plate.

Obligatory Leftorium photo in any post about left-handedness.

Obligatory Leftorium photo in any post about left-handedness.

So why are there so few lefties? One study suggests that the reason lefties are in the minority is that humans cooperate more than we compete. But the question still stands, Why Does Handedness Even Exist? The most common answer is that handedness is determined by the structure of our brains, specifically brain lateralization, referring to the fact that the two halves of our brain are not exactly alike, each with its own functional specialization. Joe Hanson of It’s OK to Be Smart made a great video explaining why some people are left handed.

Handedness is a bit more straightforward in marsupials, if you are male, you are right-handed, and if you are a girl, you are left-handed. Most of the time in humans, left handedness is a naturally occurring, normal genetic variant, and only slightly sex dependent (with men more likely to be left-handed). However, left handedness is disadvantageous and may reflect a genetic defect or early developmental disturbance, and may be considered a form of cognitive impairment (but probably not). Indeed left handedness appears to occur more frequently in groups of neurologically disordered individuals, such as those with epilepsy, Down’s Syndrome, autism, and dyslexia.

Being left-handed has its drawbacks, and there are no shortage listicles espousing those drawbacks for example, 5 Reasons Being Left-Handed Screws You for Life, 7 Downsides to Being Left-Handed, 14 Reasons School is Basically Torture for Left-Handed People, The 18 Worst Things for left-Handed People, 21 Surprising Facts About Lefties, 23 Soul-Crushing Problems Only Left-Handed People Understand, and a Reddit thread devoted to the worst products for lefties. Some of the keys points, Lefties

  • Are more likely to die sooner
  • More likely to go insane
  • More easily scared
  • Are left (pun intended) out of studies
  • May get paid less
  • Get angrier faster
  • They drink more
  • More likely to die in an accident
  • More likely to stutter
  • Are less confident
  • Have better hearing
  • Are better at competitive sports

Despite all of the numerous drawbacks, I am happy to be a lefty, just like these powerful lefties, and if you are lucky enough to have a partner who is a lefty, you might be pretty happy too.