Left-Handed Presidents

If you’re a southpaw, you’re in good Presidential company.  Many of our U.S. Presidents have been left-handed, including Harry S. Truman, Gerald R. Ford, Ronald Reagan, George H.W. Bush, Bill Clinton, and Barack Obama.

Both Presidents Truman and Reagan were switched to writing with their right hands as young school children, but photos show them favoring the left in other activities.  It’s widely believed that Herbert Hoover was also left-handed, but archivists at the Hoover Library tell us that they’ve found no documentation - it’s just left hander’s lore.

Happy International Left Handers Day!

We hope you Lefties are celebrating today.

Happy Left Handers’ Day!

NPR’s reporting on left-handedness covers two main topics: the causes of left-handedness and successful people who are left-handed (mostly presidents and baseball pitchers). 

This story, from a special series, Science Outside of the Box, takes an interdisciplinary approach to the question of left-handedness.

NPR’s Jacki Lyden talks to researcher Chris McManus who examined archived film footage of British people waving at the camera to see what he could learn about left-handedness, society, and life in the Victorian era. 

Original airdate 9/22/2007.

Study finds lefties are worse off than righties, economically speaking 

If you’re left-handed, you’re in for a rough life.

A new study by a Harvard University economist spells bad news for the 12% of people in the world who are lefties: Lefties earn a considerable amount less money than their right-handed peers. Upon examination of data from the U.S. and the U.K., Harvard professor Joshua Goodman found that lefties earn between 10% and 12% less every year than righties do.

The pay gap between lefties and righties becomes even starker when examined through the gender lens. 

In a purely competitive world, 50% of the population would be left-handed. But human evolution has been shaped by cooperation, as well as by competition - and cooperative pressure pushes handedness in the opposite direction. Could this explain why today, about one-tenth of the world’s population are southpaws - and it’s been that way for nearly 500,000 years?

From the TED-Ed Lesson Why are some people left-handed? - Daniel M. Abrams

Animation by TED-Ed

Genome search still can’t explain lefties

New research rules out a “strong genetic determinant” in influencing left- or right-handedness. The researchers conducted a twin study examining the whole genome—which contains hereditary information—of nearly 4,000 subjects from the London Twin Research Unit to compare left- and right-handed participants. Their findings are published in the journal Heredity. The study was unable to find a strong genetic factor in determining handedness. If there was a single major genetic determination of handedness, there should be a detectable shift between left- and right-handed people in the frequency of variants in that part of the genome—and this isn’t the caseStudy author John Armour, professor of human genetics at the University of Nottingham, says: “There should be a detectable shift between right- and left-handed people because modern methods for typing genetic variation cover nearly all of the genome. A survey that compared the whole-genome genotypes for right- and left-handed people should leave such a gene nowhere to hide.” (via Genome search still can’t explain lefties | Futurity)

The Anglo-Saxon lyft means weak or broken, and even modern dictionaries include such meanings for left as “defective,” “crippled,” “awkward,” “clumsy,” “inept,” and “maladroit,” the latter one borrowed from French, translated literally as “bad right.” Most definitions of left reduce to an image of doubtful sincerity and clumsiness, and the Latin word for left, sinister, is a well-known beauty. From this version springs my favorite term for left-handedness, “the bend sinister,” which Vladimir Nabokov used for the title of a book that has nothing to do with handedness.
—  Apparently, it’s International Left-Hand Day – celebrate with the evolutionary mystery of left-handedness and what it reveals about how all brains work
The only thing I couldn’t cure myself of was being left-handed. I do everything with my left hand, and no matter how I try I can’t change the habit. I just seem to do everything back to front. I used to even write backwards. Every time the schoolmasters would look at my handwriting they would throw swinging fits
—  Paul McCartney