It's National Siblings Day! To mark the occasion, guest host Selena Simmons-Duffin is exploring a detail very personal to her: How the number of older brothers a person has can influence their sexuality. Scientific research on sexuality has a dark history, with long-lasting harmful effects on queer communities. Much of the early research has also been debunked over time. But not this "fraternal birth order effect." The fact that a person's likelihood of being gay increases with each older brother has been found all over the world – from Turkey to North America, Brazil, the Netherlands and beyond. Today, Selena gets into all the details: What this effect is, how it's been studied and what it can (and can't) explain about sexuality.Interested in reading more about the science surrounding some of our closest relatives? Check out more stories in NPR's series on The Science of Siblings. Email us at shortwave@npr.org — we'd love to hear from you.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

It's baseball season! And when we here at Short Wave think of baseball, we naturally think of physics. To get the inside scoop on the physics of baseball, like how to hit a home run, we talk to Frederic Bertley, CEO and President of the Center of Science and Industry, a science museum in Columbus, Ohio. He also talks to host Regina G. Barber about how climate change is affecting the game. Interested in the science of other sports? Email us at shortwave@npr.org — we'd love to hear from you.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Tiny, black-capped chickadees have big memories. They stash food in hundreds to thousands of locations in the wild – and then come back to these stashes when other food sources are low. Now, researchers at Columbia University's Zuckerman Institute think neural activity that works like a barcode may be to thank for this impressive feat — and that it might be a clue for how memories work across species. Curious about other animal behavior mysteries? Email us at shortwave@npr.org.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

On April 8, the moon will slip in front of the sun, blocking its light and creating an eerie twilight in the middle of the day. Stars will come out, the air will get cold, colors will dance around the horizon. It's a full-body experience born from the total solar eclipse that will be visible from North America. Today on the show, Regina G. Barber talks to NPR science correspondent Nell Greenfieldboyce about why some people say this experience is one of the most beautiful celestial events you can see – and how to prepare for it. Want more ways to enjoy the eclipse? Check out Regina's interview with an eclipse chaser on NPR's Life Kit podcast. Share your eclipse stories with us at shortwave@npr.org! We'd love to see it!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

For Guyana the potential wealth from oil development was irresistible — even as the country faces rising seas. Today on the show, host Emily Kwong talks to reporter Camila Domonoske about her 2021 trip to Guyana and how the country is grappling with its role as a victim of climate change while it moves forward with drilling more oil. (encore)For more of Camila's reporting and pictures from her visit, check out "Guyana is a poor country that was a green champion. Then Exxon discovered oil."Want to more about how countries around the world are grappling with climate change? Write us at shortwave@npr.org to let us know — your suggestion might become a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Historic numbers of animals across the globe have become endangered or pushed to extinction. But some of these species sit in limbo — not definitively extinct yet missing from the scientific record. Rediscovering a "lost" species is not easy. It can require trips to remote areas and canvassing a large area in search of only a handful of animals. But new technology and stronger partnerships with local communities have helped these hidden, "uncharismatic" creatures come to light. Have other scientific gray areas you want us to cover in a future episode? Email us at shortwave@npr.org!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

According to the CDC, about one in four adults has a fear of needles. Many of those people say the phobia started when they were kids. For some people, the fear of needles is strong enough that they avoid getting important treatments, vaccines or tests. That poses a serious problem for public health. Researchers have helped develop a five step plan to help prevent what they call "needless pain" for kids getting injections or their blood drawn. Guest host Tom Dreisbach talks with Dr. Stefan Friedrichsdorf of UCSF Benioff Children's Hospitals, who works with a team to implement the plan at his own hospital. Friedrichsdorf told us some of the most important research on eliminating pain has come from researchers in Canada. Learn more about their work here. This episode was inspired by the reporting of our colleague April Dembosky, a journalist at member station KQED and KFF Health News. Read her digital story here.Got another question for a doctor? Email us at shortwave@npr.org.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Few humans have had the opportunity to see Earth from space, much less live in space. We got to talk to one of these lucky people — NASA astronaut Loral O'Hara. She will soon conclude her nearly seven month stay on the International Space Station. Transmitting from space to your ears, Loral talks to host Regina G. Barber about her dreams in microgravity, and her research on the ISS: 3D-printing human heart tissue, how the human brain and body adapt to microgravity, and how space changes the immune systems of plants. Have questions you want us to send to outers pace? Email us at shortwave@npr.org!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Across the animal kingdom, menopause is something of an evolutionary blip. We humans are one of the few animals to experience it. But Sam Ellis, a researcher in animal behavior, argues that this isn't so surprising. "The best way to propagate your genes is to get as many offspring as possible into the next generation," says Ellis. "The best way to do that is almost always to reproduce your whole life." So how did menopause evolve? The answer may lie in whales. Ellis and his team at the University of Exeter recently published a study in the journal Nature that studies the evolution of menopause in the undersea animals most known for it. What they uncovered may even help explain menopause in humans. Curious about other animal behavior mysteries? Email us at shortwave@npr.org.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

The number of newborns born with syphilis – a serious sexually transmitted infection – has skyrocketed 755% from 2012 to 2021. These babies have congenital syphilis, which is when the infection is passed from mother to baby during pregnancy. It can have dire consequences if left untreated. The surge has left medical professionals and public health leaders scrambling for solutions to stop the spread. Today on the show, Chicago based journalist Indira Khera talks to Emily Kwong about what's behind this mysterious public health crisis – and brings us inside Illinois' Perinatal Syphilis Warmline.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy