The Sun Is the Best Optometrist
By SANDRA AAMODT and SAM WANG
NYT
WHY is nearsightedness so common in the modern world? In the early 1970s, 25 percent of Americans were nearsighted; three decades later, the rate had risen to 42 percent, and similar increases have occurred around the world.
There is significant evidence that the trait is inherited, so you might wonder why our myopic ancestors weren’t just removed from the gene pool long ago, when they blundered into a hungry lion or off a cliff. But although genes do influence our fates, they are not the only factors at play.
In this case, the rapid increase in nearsightedness appears to be due to a characteristic of modern life: more and more time spent indoors under artificial lights.
Our genes were originally selected to succeed in a very different world from the one we live in today. Humans’ brains and eyes originated long ago, when we spent most of our waking hours in the sun. The process of development takes advantage of such reliable features of the environment, which then may become necessary for normal growth.
(More here.)
NYT
WHY is nearsightedness so common in the modern world? In the early 1970s, 25 percent of Americans were nearsighted; three decades later, the rate had risen to 42 percent, and similar increases have occurred around the world.
There is significant evidence that the trait is inherited, so you might wonder why our myopic ancestors weren’t just removed from the gene pool long ago, when they blundered into a hungry lion or off a cliff. But although genes do influence our fates, they are not the only factors at play.
In this case, the rapid increase in nearsightedness appears to be due to a characteristic of modern life: more and more time spent indoors under artificial lights.
Our genes were originally selected to succeed in a very different world from the one we live in today. Humans’ brains and eyes originated long ago, when we spent most of our waking hours in the sun. The process of development takes advantage of such reliable features of the environment, which then may become necessary for normal growth.
(More here.)
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