Left in a Right World

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Left in a Right World: Navigating Left-Handedness in a Right-Handed World

south·paw (ˈsouTHˌpô) noun: a left-handed person, especially a boxer who leads with the right hand or a baseball pitcher.

At a steady 10% of the world’s population, it’s a mystery why left-handedness has not “died out” from the gene pool altogether. With hundreds of years of suffering prejudice behind them, and a present-day society laid out for the convenience of the right-hand majority, southpaws have been left in a right world to wrestle with their environment and bring light to their valuable contribution in the process.

General handedness worldwide:

  • Right-handed: 90%
  • Left-handed: 10%

Left-handedness in the U.S.:

  • Men: 13%
  • Women: 11%
  • Under 30: 15%*
  • Over 65: 6%*

*most likely a reflection of changing attitudes about left-handedness


Theories

There are a number of questions researchers are still trying to answer:

1) Why does handedness exist in the first place?

Animals often prefer one paw or foot over another but only for certain tasks. Humans, however, are so strongly biased to one end of the spectrum over the other.

Evolutionary Theory: Archaeologists suggests that a dominant hand was “chosen” when hominin toolmaking technologies became more sophisticated. This hand bias would have made it easier to complete complex tasks, as well as simplify the learning process as they taught each other toolmaking and other skills.

2) Why choose the right over the left?

Neurological Theory: Language and speaking, for most people, is processed in the left hemisphere of the brain, the side also responsible for movement and motor skills on the right side of the body. One theory explains that right-hand dominance is the body’s way of being more efficient and using less energy by consolidating these important skills in the same hemisphere.

Evolutionary Theory: Because visual-spatial functions are normally carried out in the right-hemisphere of the brain, there is some evidence that the brain arrangement of left-handers might give them spatial and navigation skills that would have benefitted migrant prehistoric societies. As humans became more agrarian, those skills would have been less important, and there would have been a greater need for consistent group handedness to reduce accidents and increase efficiency in work.

3) Why has left-handedness continued to exist?

Fighting Hypothesis: Because right-handers are more common, “southpaws” possess a unique advantage in combat since their approach is different than the majority. This is one theory that explains why left-handedness might not have died out completely in a world with right-handed advantages. In present day, this theory has been tested with athletes, since sporting performance is likely a good indicator of fighting ability.

Proportion of left-handers in sports:

  • Interactive sports: 32% (sports where two or more opponents compete, e.g. boxing, soccer)
  • Non-interactive sports: 11% (sports where no direct opponent is involved, e.g. swimming, gymnastics)

This theory has also been supported by studies showing that in some primitive societies, there is a correlation between higher levels of violence and the incidence of left-handedness.

Homicide rate and frequency of left-handers in primitive societies:

Society

Geographic Area

Left-handers

Homicides per 100 inhabitants per year

Dioula

Burkina Faso

3.4%

0.13

Ntumu

Southern Cameroon

8.1%

0.17

Kreyol

Dominica

6.6%

3.00

Inuit

Greenland, Canada, Alaska

6.3%

1.70

Baka

Gabon

10.7%

5.00

Eipo

Irian Jaya

20.4%

30.00

Yanomamö

Venezuela

22.6%

40.00

Jimi valley

Papua New Guinea

13.0%

54.00

“Right Shift” Genetic Theory: This theory proposes that a hypothetical RS+ gene develops the language processing systems and motor skill of the left hemisphere of the brain, creating a preference for the right side of the body. The RS- gene would result in an indifference to the direction of hemisphere dominance. So anyone who inherits the RS-RS- combination of genes could be left-handed, right-handed, or even ambidextrous. This model explains how two right-handed parents could still have a left-handed child and how identical twins could have different hand preferences.

Chances of having a left-handed child:

  • Two right-handed parents: 9.5%
  • One right-handed and one left-handed parent: 19.5%
  • Two left-handed parents: 26.1%

Left-handedness in twins:

  • Identical twins: 14%
  • Fraternal Twins: 13.1%

Pairing

Identical Twins

Fraternal Twins

Individual Born Siblings

Both Right Handed

76.0%

75.3%

85.6%

One Right One Left

20.7%

23.2%

13.2%

Both Left Handed

3.4%

1.5%

1.2%

While the exact genetic link to handedness is still yet to be fully discovered, the data clearly shows that some genetic link must exist. However, for much of history, left-handedness was thought to be the result of injury, neglect, and even evil, leaving lefties on the receiving end of severe prejudice.


Historical Prejudice

Language reveals historical prejudice against the “left”

  • Left comes from Old English lyft meaning “weak, foolish.”
  • Right from Old English riht meaning “good, fair, proper.”
  • Sinister is Latin for “left, on the left side” but has come to mean “unlucky, unfavorable, harmful” or even “evil.”

Ancient civilizations equated the left-hand with evil

  • Ancient Greece: Right was associated with good; left was associated with evil and criminality.
  • Ancient Rome: The tradition originated of wearing a wedding ring on the third finger of the left hand to fend off evil that was associated with the left hand.

Recent History

  • 15th and 16th Century: In medieval europe, left-handedness was enough to identify a woman as a witch during the Inquisition and witch hunts.
  • 18th and 19th Century: In North America and Western Europe, If caught writing with the left hand, a child would have their hand tied behind their chair or receive corporal punishment.
  • 19th Century: In Cesare Lambroso’s studies of criminal traits, he identified left-handedness as a mark of criminality and pathological behavior.
  • 20th Century:
    • In Spain, Italy, Yugoslavia and Iron Curtain countries, right-handed writing was required in schools (well into the 1970s).
    • Albania declared left-handedness illegal.
    • In some African tribes, a candidate for chief could be turned down solely on the grounds of being left-handed.

Today, it is much more accepted to be left-handed. But the world is still set up to be more convenient, efficient and comfortable for the right-handed majority.


Challenges Today

Lefties face a multitude of challenges living in a right-handed world.

  • Scissors are difficult to use because the cutting edge is hidden by the top blade when cutting with the left hand; and the blades tend to get pushed apart when closing = wrinkled paper.
  • Some high school and college desks have the arm rest on the right.
  • Spiral notebooks and 3-ring binders are difficult and painful to write in.
  • Writing with a ball-point pen pushes on the ball and stops the ink flow.
  • Strangely, the pen’s tip cap slowly comes unscrewed when writing left handed.
  • Writing left to right with the left hand causes smearing.
  • Many controls in a car, including the gearshift, must be controlled with the right hand.
  • Controlling the acceleration pedal with right foot can be a challenge for left handers.
  • Markers on measuring cups are on the opposite side.
  • Sports equipment is less available for left handers.
  • Right handed handshakes can be awkward for southpaws and vise versa.
  • Can openers are designed for right hand use only.
  • Computer mouses and keyboard number pads are on the right.
  • Eating left handed means bumping elbows with the right hander to the left.
  • Door handles are on the right.
  • Tools and machinery are designed for right handers; resulting in a higher risk for accidents.
  • Serration on knives creates a crooked cut when used with the left hand.
  • Cords on credit card signing pads and chains on pens are attached to the right.
  • Wrist watches have the knob on the wrong side for left handers.
  • Shirt pockets are usually on the left for the convenience of right handers.
  • Fanning playing cards left handed hides the numbers.
  • Cold water tap is on the right.
  • Camera triggers are on the right.
  • Zippers

They have had to adapt

  • Only 50% of lefties report using a computer mouse with their left hands.
  • 68% use their right hand for scissors.
  • 74% hold a dinner knife in their right hands.

 

Cognitive Benefits

95% of right handed brains assign certain tasks to each hemisphere; the left-hemisphere handles language and speech while the right handles emotion and image processing. This is theorized to be more efficient.

Only 20% of left handed brains follow this structure. The other 80 percent have more symmetrical balance of brain function.

With a more symmetrical brain, information has to pass back-and-forth, which can lead to new and radical ideas, or thinking “outside the box.”

It has been suggested that constant adaptation and improvisation, along with the this propensity for brain symmetry, gives lefties a creative edge.

  • 4 of the 5 original designers of the Mac computer were lefties.
  • 5 of the last 7 U.S. Presidents were left-handed.
    • Gerarl R. Ford: Left-handed
    • Jimmy Carter: Right-handed
    • Ronald Reagan: Left-handed
    • George H.W. Bush: Left-handed
    • Bil Clinton: Left-handed
    • George W. Bush: Right-handed
    • Barack Obama: Left-handed
  • Musicians, painters and writers are significantly more likely to be left-handed.

Representation of left-handers among SAT high achievers:

  • Math or verbal sections: 15%
  • Both math and verbal sections – males: 17%
  • Both math and verbal sections – females: 20%
  • Compared to 10% for the general population

Their ability to adapt and to create gives southpaws a fighting chance to make their mark in a right-handed world.


Left-Handers’ Day: August 13th


left-in-a-right-world

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