(Left to right): Pictorial Parade/Archive Photos/Getty Images; Bernd Thissen/picture-alliance/dpa/AP Images; © Ken Richardson

Top stories: The evolving female orgasm, young blood in old bodies, and the Cold War secrets uncovered by climate change

New theory suggests female orgasms are an evolutionary leftover

Billy Crystal may have been shocked when Meg Ryan so effectively—and amusingly—faked an orgasm in a restaurant during the 1989 movie When Harry Met Sally, but surveys suggest only one-third of women are regularly fully aroused during intercourse. In a paper published this week, two evolutionary biologists offer a provocative new explanation—that the female orgasm is an evolutionary holdover from an ancient system, seen in some other mammals, in which intercourse stimulated important hormonal surges that drive ovulation.

Young blood antiaging trial raises questions

It was one of the most mind-bending scientific reports in 2014: Injecting old mice with the plasma portion of blood from young mice seemed to improve the elderly rodents’ memory and ability to learn. Inspired by such findings, a startup company has launched the first clinical trial in the United States to test the antiaging benefits of young blood in relatively healthy people. But there's a big caveat: It's a pay-to-participate trial, a type that has raised ethical concerns before.

Mysterious, ice-buried Cold War military base may be unearthed by climate change

It sounds like something out of a James Bond movie: a secret military operation hidden beneath the Greenland Ice Sheet. But that’s exactly what transpired at Camp Century during the Cold War. Within the next century, climate change could start to reveal this base again, and potentially release its toxic and radiological wastes.

‘Junk DNA’ tells mice—and snakes—how to grow a backbone

Why does a snake have 25 or more rows of ribs, whereas a mouse has only 13? The answer, according to a new study, may lie in “junk DNA,” large chunks of an animal’s genome that were once thought to be useless. The findings could help explain how dramatic changes in body shape have occurred over evolutionary history.

Meet the college dropout who invented the gravitational wave detector

Nearly 50 years ago, Rainer Weiss dreamed up a way to detect gravitational waves—infinitesimal ripples in spacetime predicted by Einstein’s theory of gravity, general relativity. Last September, that dream came true as 1000 physicists working with the Laser Interferometer Gravitational-Wave Observatory, two huge detectors in Livingston, Louisiana, and Hanford, Washington, sensed a pulse of waves radiated by two massive black holes as they spiraled into each other a billion light-years away. The discovery makes Weiss, a physicist at the Massachusetts Institute of Technology in Cambridge, a sure bet to win a Nobel Prize, his peers say.

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