Short Wave

Chocolate may never be the same. The majority of chocolate is made in just two countries and erratic weather from climate change is decreasing cocoa production. A handful of extreme weather events—from drought to heavy rainfall—could have lasting effects on the chocolate industry. Yasmin Tayag, a food, health and science writer at The Atlantic, talks to host Emily Kwong about the cocoa shortage: What's causing it, how it's linked to poor farming conditions and potential solutions. Plus, they enjoy a chocolate alternative taste test. Read Yasmin's full article. Have a food science story you want us to cover? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

As artificial intelligence seeps into some realms of society, it rushes into others. One area it's making a big difference is protein science — as in the "building blocks of life," proteins! Producer Berly McCoy talks to host Emily Kwong about the newest advance in protein science: AlphaFold3, an AI program from Google DeepMind. Plus, they talk about the wider field of AI protein science and why researchers hope it will solve a range of problems, from disease to the climate. Have other aspects of AI you want us to cover? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Scientists at the National Oceanic and Atmospheric Administration observed a cluster of sunspots on the surface of the sun this week. With them came solar flares that kicked off a severe geomagnetic storm. That storm is expected to last throughout the weekend as at least five coronal mass ejections — chunks of the sun — are flung out into space, towards Earth! NOAA uses a five point scale to rate these storms, and this weekend's storm is a G4. It's expected to produce auroras as far south as Alabama. To contextualize this storm, we are looking back at the largest solar storm on record: the Carrington Event. Want us to cover more about the sun? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Sam and John Fetters, 19, are identical twins on different ends of the autism spectrum. Sam is a sophomore at Amherst College and runs marathons in his free time. John attends a school for people with special needs and loves to watch Sesame Street in his free time. Identical twins like Sam and John pose an important question for scientists: How can a disorder that is known to be highly genetic look so different in siblings who share the same genome? Check out more of NPR's series on the Science of Siblings. More science questions? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Emily gets super nerdy with former host Maddie Sofia get as they dive into the incredible world of nudibranchs in this encore episode. Not only are these sea slugs eye-catching for their colors, some of them have evolved to "steal" abilities from other organisms — from the power of photosynthesis to the stinging cells of their venomous predators. These sea slugs are going to blow your mind! You can email Short Wave at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

It's not unusual for siblings to quibble over ownership of something — a cherished toy, a coveted seat in the car — or whose fault something is. If you're Mercedes Sheen, you not only spent your childhood squabbling with your sister over your memories, you then turn it into your research career. Mercedes studies disputed memories, where it's unclear who an event happened to. It turns out these memories can tell us a lot about people — they tend to be self-aggrandizing — and how the human brain remembers things. Check out more of NPR's series on the Science of Siblings. Curious about more science about memories? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Wildlife ecologists have seen white-tailed deer expanding their range in North America over many decades. And since the early-2000s these deer have moved north into the boreal forests of western Canada. These forests are full of spruce and pine trees, sandy soil and freezing winters with lots of snow. They can be a harsh winter wonderland. And ecologists haven't known whether a warmer climate in these forests or human land development might be driving the deer north. A recent study tries to disentangle these factors – and finds that a warming climate seems to play the most significant role in the movement of deer. Read more in the journal Global Change Biology. Curious about more wildlife news? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

No matter what you're doing right now – sitting, standing, walking – you're moving. First, because Earth is spinning around on its axis. This rotation is the reason we have days. Second, because Earth and other planets in our solar system are orbiting the sun. That's why we have years. Third, you're moving because the sun and the rest of our solar system is orbiting the center of the Milky Way galaxy at over 500,000 miles per hour. If all of that isn't nauseating enough, everything in the entire universe is expanding outward. All the time. But in the 1970s, astrophysicists noticed something strange about our galactic neighborhood, or Local Group. The whole clump of neighboring galaxies was being pulled off course at over one million miles per hour, towards something we couldn't see — the "Great Attractor." This Great Attractor sits in the "Zone of Avoidance," an area of space that is blocked from view by the stars and gas of the Milky Way. Today on the show, host Regina G. Barber talks to astrophysicist Jorge Moreno about this mysterious phenomenon: What it might be and what will happen when we eventually reach it. Curious about other cosmic mysteries? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Today, we're going full nerd to talk about a new board game — Catan: New Energies. The game's goal is simple: Build and develop a modern-day island without catastrophically polluting it. Although the concept mirrors the effects of climate change, those words don't actually appear in the game. NPR correspondent Nate Rott talks to Emily about the thinking behind the new game and how the developers hope it can start conversations around energy use and pollution. Have questions or comments for us to consider for a future episode? Email us at shortwave@npr.org — we'd love to hear from you! Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Ten years ago, Flint, Mich. switched water sources to the Flint River. The lack of corrosion control in the pipes caused lead to leach into the water supply of tens of thousands of residents. Pediatrician Mona Hanna-Attisha recognized a public health crisis in the making and gathered data proving the negative health impact on Flint's young children. In doing so, she and community organizers in Flint sparked a national conversation about lead in the U.S. water system that persists today. Today on the show, host Emily Kwong and science correspondent Pien Huang talk about the state of Flint and other cities with lead pipes. Efforts to replace these pipes hinge on proposed changes to the EPA's Lead and Copper Rule. Have questions or comments for us to consider for a future episode? Email us at shortwave@npr.org — we'd love to hear from you! Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

NPR's Tom Dreisbach is back in the host chair for a day. This time, he reports on a story very close to home: The years-long battle his parents have been locked in with the local wild beaver population. Each night, the beavers would dam the culverts along the Dreisbachs' property, threatening to make their home inaccessible. Each morning, Tom's parents deconstructed those dams — until the annual winter freeze hit and left them all in a temporary stalemate. As beaver populations have increased, so have these kinds of conflicts with people...like Tom's parents. But the solution may not be to chase away the beavers. They're a keystone species that scientists believe could play an important role in cleaning water supplies, creating healthy ecosystems and alleviating some of the effects of climate change. So, today, Tom calls up Jakob Shockey, the executive director of the non-profit Project Beaver. Jakob offers a bit of perspective to Tom and his parents, and the Dreisbachs contemplate what a peaceful coexistence with these furry neighbors might look like. Have questions or comments for us to consider for a future episode? Email us at shortwave@npr.org — we'd love to hear from you! Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Roughly 196 million tons of fish were harvested in 2020, according to the Food and Agriculture Organization of the United Nations. The organization also notes that the number of overfished stocks worldwide has tripled in the last century. All of this overfishing has led to the decline of entire species, like Atlantic cod. Enter the Monterey Bay Aquarium's Seafood Watch. It and other free guides give consumers an overview of the world of fish and seafood, helping people to figure out the most sustainable fish available to them. With the help of Life Kit's Clare Marie Schneider, we figure out how to make informed decisions about what we eating – whether that's at a restaurant or the local supermarket. Check out more from Life Kit on sustainable seafood. Have questions or comments for us to consider for a future episode? Email us at shortwave@npr.org — we'd love to hear from you! A previous version of this episode incorrectly stated that there are native wild salmon in Chile. Salmon are not native to Chile. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

When the dinosaurs walked the Earth, massive marine reptiles swam. Among them, a species of Ichthyosaur that measured over 80 feet long. Today, we look into how a chance discovery by a father-daughter duo of fossil hunters furthered paleontologist's understanding of the "giant fish lizard of the Severn." Currently, it is the largest marine reptile known to scientists. Read more about this specimen in the study published in the journal PLOS One. Have another ancient animal or scientific revelation you want us to cover? Email us at shortwave@npr.org — we might talk about it on a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

500 million years ago, the world was a very different place. During this period of time, known as the Cambrian period, basically all life was in the water. The ocean was brimming with animals that looked pretty different from the ones we recognize today — including a group of predatory worms with a throat covered in teeth and spines. Researchers thought these tiny terrors died out at the end of the Cambrian period. But a paper published recently in the journal Biology Letters showed examples of a new species of this worm in the fossil record 25 million years after scientists thought they'd vanished from the Earth. One of the authors of the paper, Karma Nanglu, tells us how this finding may change how scientists understand the boundaries of time. Curious about other weird wonders of the ancient Earth? Email us at shortwave@npr.org. Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

We've all been there: You sit down for one episode of a reality TV show, and six hours later you're sitting guiltily on the couch, blinking the screen-induced crust off your eyeballs. Okay. Maybe you haven't been there like our team has. But it's likely you have at least one guilty pleasure, whether it's playing video games, reading romance novels or getting swept into obscure corners of TikTok. It turns out that experiencing – and studying – pleasure is not as straightforward as it might seem. And yet, pleasure is quite literally key to the survival of humanity. So today on the show, we explore the pleasure cycle: What it is, where it lives in the brain and how to have a healthier relationship with the things that make us feel good. Want more on the brain? Email us the neuroscience you want us to talk about at shortwave@npr.org! (Also please email us if you would like to gush about any of the books you've been loving — romantasy or otherwise!) Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

Wednesday the Environmental Protection Agency announced new drinking water standards to limit people's exposure to some PFAS chemicals. For decades, PFAS have been used to waterproof and stain-proof a variety of consumer products. These "forever chemicals" in a host of products — everything from raincoats and the Teflon of nonstick pans to makeup to furniture and firefighting foam. Because PFAS take a very long time to break down, they can accumulate in humans and the environment. Now, a growing body of research is linking them to human health problems like serious illness, some cancers, lower fertility and liver damage. Science correspondent Pien Huang joins the show today to talk through this new EPA rule — what the threshold for safe levels of PFAS in tap water is, why the rule is happening now and how the federal standards will be implemented. Read more of Pien's reporting on the EPA's first ever rule on PFAS in drinking water. Want to hear more about health and human safety? Email us at shortwave@npr.org — we might cover your question on a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoices NPR Privacy Policy

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/adchoices NPR 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/adchoices NPR 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/adchoices NPR 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/adchoices NPR Privacy Policy