Short Wave

Was there ever life on Mars? Planetary scientists think there could have been but there hasn’t been any direct evidence. After years of roaming Mars, NASA’s Perseverance rover saw spots on Mars rocks. These spots could be the most likely clue that Mars had organic life millions of years ago. Host Regina G. Barber speaks with recent PhD graduate and planetary scientist Hemani Kalucha. She explains why the size, shape and color of these spots – as well as the location of these rocks on Mars – point to ancient life. Interested in more science behind skincare products? Email us your question at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Brain-computer interfaces (BCIs) are surgically implanted devices that link the brain to a computer. They can be helpful for people who’ve lost the ability to move or speak. And they’re making progress. New generations of BCIs could go as far as to detect a person’s inner monologue. But that progress is raising questions about the future privacy of our brains, and has some scientists asking, “What happens when you want to keep some things to yourself?” NPR brain correspondent Jon Hamilton talks to Short Wave’s Emily Kwong about the future of BCIs. Read more of Jon’s reporting on brain implants. Interested in more on the future of brain science? Email us your question at shortwave@npr.org – we may feature it in an upcoming episode! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Christopher Nolan’s Interstellar was a phenomenon in 2014. Set in the future, Earth has been struck by a global crop blight. Former NASA pilot Cooper (Matthew McConaughey) is pulled into a NASA mission to transport the human race to a new planet, via wormhole. Back on Earth, Cooper’s daughter, Murph (Jessica Chastain), attempts to complete an equation that will allow this mass-transport of humanity from Earth. Many scientists praised the film, particularly for its depiction of black holes. In this episode co-hosts Regina G. Barber and Emily Kwong talk about Interstellar with Star Trek scientific advisor and astrophysicist Erin Macdonald. They walk through wormholes, black holes and all the ways space-time stretches in the film. Interested in more on the science behind science fiction? Email us your question at shortwave@npr.org – we may feature it in an upcoming episode! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

U.S. consumers spend more than $10 billion a year on sports drinks, according to Beverage Industry, a trade publication. And we can’t lie that sometimes a Gatorade or electrolyte tablet sounds really appealing in the quest to hydrate daily – especially since it’s been a very hot, long summer. But the question is: Are we even sweating enough to warrant all these sugary electrolyte-filled drinks? NPR health correspondent Pien Huang has been on the case, and she brings us answers she’s racked up in her reporting today. Read more of Pien’s reporting on electrolytes and hydration. Interested in more consumer health or human biology stories? Email us your question at shortwave@npr.org – we may feature it in an upcoming episode! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Mars is known for its barren desert landscape and dry climate. But two recent studies in the journals Nature and Science go beneath the surface, exploring the interior of the red planet using seismic data from NASA’s InSight mission. And now, this data is also giving scientists a glimpse into the planet’s history – to see how Mars evolved over billions of years and how its inner structure compares to that of Earth. Interested in more science news? Let us know at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

For a long time, scientists have suspected that stuttering — a common speech condition that affects an estimated 1 in every 100 people — could be heritable. Despite how common it is, it's still a remarkably understudied condition. Geneticists Piper Below and Dillon Pruett were determined to fix that. With the help of 23andMe data, they recently identified 57 genetic regions linked to stuttering in the human genome. Their findings represent a new breakthrough in how researchers think about speech conditions, genetics and the conditions that are linked to them. They're what some are calling a "quantum leap" in the field. Interested in more human biology and genetics episodes? Email us your question at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

More than 1 in 10 people in the United States take an antidepressant. And the most commonly prescribed type of antidepressant are SSRIs — or selective serotonin reuptake inhibitors. That includes drugs like Zoloft, Prozac and Lexapro. But what happens when some patients decide they want to stop taking their SSRIs? While doctors know stopping SSRIs can sometimes cause unpleasant short-term side effects – like dizziness, anxiety, insomnia and nausea – some people report symptoms that last months, even years. So, with investigative reporter Emily Corwin and professor of clinical psychology Michael Hengartner, we’re diving into the research around the long-term effects of going off your antidepressants – what it shows and its limits. Read more of Emily Corwin’s reporting on the topic here. Want more stories on mental health? Email us at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Monday night football is back! What better way to celebrate than a close look at some of the physics powering the sport? Specifically, the spiral pass. If you've ever watched part of a professional football game, you've probably seen a tight spiral pass. They're those perfect throws where the football leaves the player's hand and neatly spins as it arcs through the air. Those passes can seem to defy fundamental physics — and for a long time, scientists couldn't figure out exactly why. That is, until experimental atomic physicist Tim Gay cracked the case within the last few years. His answer comes after two decades of hobby research and more than a couple late night shouting matches with two other physicists over Zoom. (encore) Want more stories on sports science? Email us at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

The United Nations estimates that there were over 1.5 million new cases of skin cancer in 2022. That number might have you reaching for the nearest tube of sunscreen. And it might also have you wondering what truth there is to the hype around Korean and European sunscreens. Click around online and you’ll see lots of claims about the superiority of their protection against UV radiation compared to products made in the United States. But are sunscreens sold in the U.S. really so subpar? With the help of chemist and science communicator Michelle Wong, we wade into the research of UVA and UVB rays, the complexities of regulating cosmetics and drugs, and how to maximize your protection against the sun no matter which sunscreens you have access to. Interested in more science behind skincare products? Email us your question at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

The Inca Empire in South America was one of the most powerful pre-Columbian societies. It was known for the architecture of Machu Picchu, an extensive road network and a system of terraces for agriculture. The society also kept records known as khipu, which involved a system of tying knots to encode sophisticated information. Literacy in this form of writing was assumed to be something that only the highest levels of Inca society could do. But NPR science correspondent Nell Greenfieldboyce shares how a new analysis of a cord made out of human hair may change that assumption. Curious about science history? Email us at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Feel like summers are hotter than they used to be? It’s not just your imagination. Climate researchers say that average annual temperatures around the country have been trending upwards for the past 50 years — and are still on the rise. But it can be hard to represent those numbers in a way that makes sense to everyday people. So Gulf States Newsroom reporter and New Orleans resident Drew Hawkins wondered: What if he could help people hear those changes for themselves? Turn temperatures into tunes? This episode is part of Nature Quest, a monthly Short Wave segment that answers listener questions about their local environment. Got a question about changes in your local environment? Send a voice memo to shortwave@npr.org with your name, where you live and your question. We might make it into our next Nature Quest episode! Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Deep sea mining for rare earth elements could start as early as 2026, even as 38 countries have called for a moratorium on it. The metals that companies are targeting are used in many green technologies like electric cars and wind turbines – but mining them is destructive to the environment. Some in the mining industry say the mining is necessary to a green transition – and essential to democratizing that transition globally since the supply chain is currently dominated by a single country, China. Meanwhile, some scientists caution against mining before the full scope of environmental damage can be understood. Can there be balance in this environmental and political push-and-pull? Hosts Regina G. Barber and Emily Kwong dive into this debate and talk about what science has to say. Curious about other science controversies? Email us at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Chocolate may fill grocery store shelves around the world, but the raw product that powers chocolate is far more selective. The majority of chocolate farms are found in West Africa and South America – just 20 degrees north or south of the equator. Each farm produces chocolate of a different flavor. Some cocoa tastes fruitier; others, more floral. Nutty. Earthy. Spicy. But what drives these different flavor profiles? And can it be recreated in a lab? A team led by scientists at the University of Nottingham in the UK sought to find out and published their results in the journal Nature Microbiology this week. Curious about other ways science intersects with food? Email us at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Thirty years ago, park rangers reintroduced grey wolves into Yellowstone National Park. They wanted to restore the ecosystem and get the elk population, which had decimated the plant community, in check. And it worked – or so the popular narrative suggests. But is it really so simple? Today on the show, we explore how the Yellowstone ecosystem has changed since wolves returned and whether those changes can really be pinned solely on wolves. Plus, how the narrative of the Yellowstone wolf legacy could affect wolf reintroduction elsewhere. Curious about other science controversies? Email us at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Imagine, you’re a toxic toad hanging around South America. No other animals are gonna mess with you, right? After all, you’re ~toxic~! So if anyone tries to eat you, they’ll be exposed to something called a cardiotonic steroid — and may die of a heart attack. Well, unfortunately, for you, some animals have developed adaptations to these toxic steroids. Evolutionary biologist Shabnam Mohammadi has spent her career studying how these adaptations work — and says even humans have used these toxins to their advantage since ancient Egypt. So today on Short Wave, we get a little… toxic (cue Brittney Spears). Host Regina G. Barber talks to Shabnam about how some predators can get away with eating toxic prey. Curious about biology? Email us at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Scientists have mapped less than 30% of the world's seafloor. Experts say that getting that number up to 100% would improve everything from tsunami warnings to the Internet and renewable energy. That's why there's currently a global effort to create a full, detailed map of the seabed by 2030. On today's Sea Camp episode, we talk to Dawn Wright, a marine geographer and chief scientist at the Environmental Systems Research Institute about this effort. We have a newsletter that lets you go even deeper with the marine research each week of Sea Camp. You can sign up here! Curious about ocean science? Email us at shortwave@npr.org. Listen to Short Wave on Spotify and Apple Podcasts. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

In this Back To School episode we consider the "List of Life": the criteria that define what it is to be a living thing. Some are easy calls: A kitten is alive. A grain of salt is not. But what about the tricky cases, like a virus? Or, more importantly, what about futuristic android robots? As part of our Black History Month celebration, developmental biologist Crystal Rogers and Short Wave co-host Regina G. Barber dig into what makes something alive, and wade into a Star-Trek-themed debate. Listen to Short Wave on Spotify and Apple Podcasts. Is there something you'd like us to cover? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Neurotic, anxious robots like C-3P0 from Star Wars' C-3P0 and Marvin from The Hitchhiker's Guide to the Galaxy are a staple of science fiction — but they're not as common in the real world. Most of the time, the chatbots and artificial intelligence "robots" we encounter are programmed to be extraverted, confident and cheerful. But what if that changed? NPR science correspondent Nell Greenfieldboyce dives into the world of robot personality research and talks to a team of researchers that are experimenting with a very different kind of robot temperament. Read more of Nell's reporting on the topic here. Interested in more science news? Let us know at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Love podcasts? For handpicked recommendations every Friday, subscribe to NPR's Pod Club. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

A Chinese scientist, He Jiankui, made a shocking announcement to the world in 2018: He had secretly engineered the birth of the first gene-edited babies. The birth of the twins was seen as reckless and unethical by the scientific community. That’s because, among other things, the CRISPR gene-editing technique Jiankui used was so new. NPR science correspondent Rob Stein has been following the controversial world of gene-editing and human reproduction, including some companies’ recent quests to push gene-editing technology forward. Read more of Rob Stein’s reporting on the topic here. Interested in more science news? Let us know at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

How did life start on Earth? The answer is a big scientific mystery scientists are actively investigating. After talking with many scientists, host Regina G. Barber found that an abundance of water on Earth is most likely key, in some way, to the origin of life — specifically, in either deep sea hydrothermal vents or in tide pools. It's for this reason some scientists are also exploring the potential for life in so-called "water worlds" elsewhere in the solar system, like some of the moons of Jupiter and Saturn. This episode, Regina digs into two water-related hypotheses for the origin on life on Earth — and what that might mean for possible alien life. Have another scientific mystery you want us to cover on a future episode? Email us at shortwave@npr.org. Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy