Thursday, April 06, 2017

Accelerating Human Evolution

If you have a chance, pick up the April 2017 issue of NATIONAL GEOGRAPHIC and check out the cover article, "The Next Human." Contrary to popular belief, the human species hasn't stopped evolving. This article mentions several examples of recent evolutionary change, such as the two most widely known: While most ethnic groups lose the ability to digest milk in adulthood, a few have developed adult lactose tolerance, which led to cultures based on dairy herds. The gene for sickle cell anemia causes a serious disease when doubled, but inheriting only one copy of the gene seems to provide resistance against malaria. Adaptations less familiar to the general reader include populations living at high altitudes who have evolved a hemoglobin trait that enables them to use oxygen more efficiently and desert dwellers who can handle a wider range of temperature extremes than most people.

Evolution doesn't have to wait for the slow processes of nature anymore, though. Technologies such as CRISPR can alter genes to order. Few people would object to using genetic engineering to correct disabling or lethal inherited conditions. But what about choosing an embryo's eye and hair color or trying to enhance intelligence in utero?

The article, however, also explores technological advances that adapt users to the environment in ways natural processes alone can't. One man born with achromatopsia—he's literally color-blind, seeing only blacks, whites, and grays—has an antenna attached to a sensor in his brain that enables him to perceive colors. Not only that, he goes beyond ordinary human vision to "see" infrared and ultraviolet. Hundreds of people have been implanted with devices that allow them to unlock doors or log onto computers without touching anything. The University of Southern California is running tests on "chip implants in the brain to recover lost memories."

Does becoming a cyborg count as a form of "evolution"?

Margaret L. Carter

Carter's Crypt

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