Seven Big Misconceptions about Heredity

Posted on May 1, 2019July 1, 2021 by Matt Kristoffersen

Skeptical Inquirer, May/June 2019

If someone says, “I guess it’s in my DNA,” you never hear people say, “DN—what?” We all know what DNA is, or at least think we do.

It’s been seven decades since scientists demonstrated that DNA is the molecule of heredity. Since then, a steady stream of books, news programs, and episodes of CSI have made us comfortable with the notion that each of our cells contains three billion base pairs of DNA, which we inherited from our parents. But we’ve gotten comfortable without actually knowing much at all about our own genomes.

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Denisovan Jawbone Discovered in a Cave in Tibet

Posted on May 1, 2019May 26, 2020 by Zimmer

The New York Times, May 1, 2019

Link

In 1980, a Buddhist monk in Tibet entered a sacred cave to pray. On the floor, he found half of a human jawbone, studded with two teeth.

A team of scientists on Wednesday reported that the fossil belonged to a 160,000-year-old Denisovan, a member of a lineage of mysterious, Neanderthal-like humans that disappeared about 50,000 years ago.

The fossil is the first evidence of this species found outside the Denisova Cave in Siberia, buttressing the theory that these relatives of modern humans once lived across much of central and eastern Asia.

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Scott Kelly Spent a Year in Orbit. His Body Is Not Quite the Same.

Posted on April 11, 2019May 25, 2020 by Zimmer

The New York Times, April 11, 2019

Link

For 340 days, Scott Kelly circled the Earth aboard the International Space Station, gathering data about himself.

He drew blood from his arms. He saved his urine. He played computer games to test his memory and reaction speed. He measured the shape of his eyes.

Two hundred and forty miles below, Mr. Kelly’s twin brother, Mark, who also served as an astronaut, carried out identical tests. Now, a comparison of these two men has provided a unique opportunity to learn what happens to the human body in space — down to the molecular level.

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4 Takeaways From That Huge Study of Scott Kelly

Posted on April 11, 2019May 25, 2020 by Zimmer

The New York Times, April 11, 2019

Link

There’s never been a study like it before, and there probably never will be again.

Starting in March 2015, astronaut Scott Kelly spent 340 days aboard the International Space Station. A team of scientists tracked his body’s responses to long-term spaceflight in painstaking detail. They simultaneously tracked his identical twin brother, Mark, on Earth.

On Thursday, the scientists began publishing the huge trove of results from the so-called NASA Twins Study — 90 pages, all told, and that’s just the first installment. Here’s a guide to what they’ve found … so far.

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