Lefties earn less, have lower test scores than righties

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Throughout the ages, there have been superstitions and myths spread about left-handed people. Back in the Middle Ages left-handed writers were thought to be possessed by the devil—hence the Latin name sinistra for the word “left.” Likewise, negative connotations can be found in root languages across Europe and even in the Mandarin dialect in China.

The modern day United States and UK have reformed since the Dark Ages. Lefties have come into vogue, being thought to posses higher IQs. Some mothers may even wish that their offspring will be born with this genetic gift, but Peter R. Orszag of Bloomberg View references a recent study that may dispel this myth. In fact, if you’re born left-handed you may be at a predisposed disadvantage, and it has nothing to do with genetics.

It’s estimated that 12 percent of the world’s population is left-handed. You’ll find that more men than women are southpaws and your chances increase if your mother is also a lefty. Joshua Goodman, an economist at Harvard’s Kennedy School, has released a paper, analyzing how a combinations of environmental and genetic factors will lead a significant portion of these lefties to earn 10 to 12 percent less than righties at their jobs, and also score lower on cognitive tests.

Goodman takes his findings from five databases from the US And UK that notes handedness, family characteristics, earnings, and test scores. He sees a trend emerge among the data points:

“Lefties have more emotional and behavioral problems, have more learning disabilities such as dyslexia, complete less schooling, and work in occupations requiring less cognitive skill.”

Why left-handed people are given such a bleak outlook has nothing to do with genetics, according to Goodman. In fact, his theory on the lefty disadvantage applies to righties as well. Children who are born with a dominate hand opposite to their mother’s have difficulties mimicking in the early phases of life.

“Interestingly, lefties with left-handed mothers show no cognitive deficits relative to righties. Some of these facts have been documented previously, though not across the range of datasets used here.”