For decades, Coho salmon were turning up dead in urban streams the Pacific Northwest. The salmon would stop swimming straight, and then die before they had a chance to spawn. Researchers worried that unless they figured out the cause, the species would eventually go extinct. Enter a formidable crew of biologists, modelers, community scientists, environmental chemists. After eventually ruling out the obvious suspects — things like temperature, oxygen levels and known toxins — researchers eventually zeroed in on a prime suspect: chemicals in tires. But the question remained: Which one? If you liked this episode, check out our other episodes on satellites monitoring emissions and how air pollution could create superbugs.Want to hear more environmental stories or science mysteries? Tell us by emailing 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/adchoicesNPR Privacy Policy

Many people are gearing up for holiday conversations with loved ones who may disagree with them — on everything from politics to religion and lifestyle choices. As the conversations unfold, these divisions are visible in our brains too. These conversations can get personal and come to a halt fast. But today on the show we get into research in neuroscience and psychology showing that as much as we disagree, there are ways to bridge these divides – and people who are actively using these strategies in their daily lives. Want to hear more neuroscience and psychology? Email us your ideas to shortwave@npr.org — we'd love to hear from you!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/adchoicesNPR Privacy Policy

Getting enough sleep regularly can be tough — and even harder when you're traveling for the holidays. "We need sleep like we need water," says Jade Wu, a behavioral sleep medicine psychologist and author of the book Hello Sleep. She and host Regina G. Barber discuss what's happening to our bodies when we get jet lag and the clocks in our body get out of whack. They also get into the science of the circadian rhythm and how to prepare for a long flight across time zones. Check out CDC's website for tips on minimizing jet lag.Want to hear more science of holiday living? Email us your ideas to shortwave@npr.org — we'd love to hear from you! 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/adchoicesNPR Privacy Policy

This critter lurks in the ocean's midnight zone, has a voluminous hood, is completely see through and is bioluminescent. It's unlike any nudibranchs deep sea experts have ever seen before — and now, the researchers who spent twenty years studying them have finally published their findings. Have another scientific discovery you want us to cover on a future episode? Email us at shortwave@npr.org — we might feature your idea on a future 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/adchoicesNPR Privacy Policy

As global warming continues and space technology improves, there is more and more talk about the growing possibility of a sci-fi future in which humans become a multiplanetary species. Specifically, that we could live on Mars. Biologist Kelly Weinersmith and cartoonist Zach Weinersmith have spent the last four years researching what this would look like if we did this anytime soon. In their new book A City On Mars, they get into all sorts of questions: How would we have babies in space? How would we have enough food? They join host Regina G. Barber and explain why it might be best to stay on Earth. Kelly and Zach Weinersmith's book A City On Mars is out now.Have another space story you want us to cover on a future episode? Email us at shortwave@npr.org — we'd love to hear from you! Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

One in four U.S. households experiences a power outage each year. Scientists at Oak Ridge National Laboratory are working on technology they hope will help fix electric grids: drones. They're betting that 2-ft. large drones connected to "smart" electric grids are a cost-effective step to a more electrified future.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. Have an idea for a future episode? We'd love to know — email us at shortwave@npr.org!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

In this episode, you're invited to the fermentation party! Join us as we learn about the funk-filled process behind making sauerkraut, sourdough and sour beer. Plus, no fermentation episode is complete without a lil history of our boy, yeast.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

A pivotal week in Corey Gray's life began with a powwow in Alberta and culminated with a piece of history: The first-ever detection of gravitational waves from the collision of two neutron stars. Corey was on the graveyard shift at LIGO, the Laser Interferometer Gravitational-Wave Observatory in Hanford, Washington, when the historic signal came. This episode, Corey talks about the discovery, the "Gravitational Wave Grass Dance Special" that preceded it and how he got his Blackfoot name. (encore)Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

In North-Central New Jersey, there is a backyard teeming with around 200 turtles. Many of these shelled creatures have been rescued from the smuggling trade and are now being nursed back to health in order to hopefully be returned to the wild. Science reporter Ari Daniel joins host Regina G. Barber to tell the story behind one man's efforts to care for these turtles and to ensure they have a chance at another (better) life. Read more of Ari's reporting.Have an idea for a future episode? We'd love to know — 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/adchoicesNPR Privacy Policy

It's Election Day in the United States. Across the nation, millions of ballots are being cast. But what would happen if the rules of our electoral system were changed? Certain states are about to find out. This year, several places have alternative voting systems up for consideration on their ballots, and those systems could set an example for voting reform throughout the rest of the country. Short Wave producer Hannah Chinn and host Emily Kwong dive into three voting methods that are representative of those systems: Where they've been implemented, how they work, and what they might mean for elections in the future. What to hear more about the math powering our lives? Email us at shortwave@npr.org and we might cover your idea on a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR 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 — we might feature your idea on a future episode!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

For years, we've been asking, "Which came first: the chicken or the egg?" Maybe what we should have been asking is, "Which came first: the frog or the tadpole?" A new paper in the journal Nature details the oldest known tadpole fossil. Ringing in 20 million years earlier than scientists previously had evidence of, this fossil might get us closer to an answer.Have another scientific discovery you want us to cover on a future episode? Email us at shortwave@npr.org — we might feature your idea on a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

NOTE: This episode contains multiple high-pitched noises (human and other animals) that some listeners might find startling or distressing.In this episode, host Regina G. Barber and NPR correspondent Nate Rott dive into the science behind the sound of fear. Along the way, they find out what marmot shrieks, baby cries and horror movie soundtracks have in common — and what all of this tells us about ourselves.If you like this episode, check out our episode on fear and horror movies.Curious about other science powering the human experience? Email us at shortwave@npr.org and we might cover your topic on a future episode!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Humans have seen a significant increase in life expectancy over the past 200 years — but not in overall lifespan. Nobody on record has lived past 122 years. So, for this early Halloween episode, host Regina G. Barber asks: Why do we age and why do we die? Microbiologist Venki Ramakrishnan explains some of the mechanisms inside of our bodies that contribute to our decay — and tells us if it's possible to intervene in the process.Curious about other biology news? Email us at shortwave@npr.org and we might cover your topic on a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

What's your favorite apple? Maybe it's the crowd-pleasing Honeycrisp, the tart Granny Smith or the infamous Red Delicious. Either way, before that apple made it to your local grocery store or orchard it had to be invented — by a scientist. So today, we're going straight to the source: Talking to an apple breeder. Producer Hannah Chinn reports how apples are selected, bred, grown ... and the discoveries that could change that process. Plus, what's a "spitter"?Want to know how science impacts other food you eat? Email us at shortwave@npr.org and we might cover your food of choice on a future episode!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

More than a million species are at risk of extinction, many within decades, because of human actions. Among them? The kāhuli, Hawaii's native tree snails that are some of the most endangered animals on the planet. At one point, there used to be about 750 species of snails in Hawaii — almost all of them found nowhere else. Now, they are rapidly disappearing. NPR climate reporters Lauren Sommer and Ryan Kellman join host Emily Kwong to tell the story of the small team caring for the last of some of these snail species — and their fight against extinction. Read more of Lauren and Ryan's reporting.Curious about other biodiversity news? Email us at shortwave@npr.org and we might cover your topic on a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

For the past 70 years, schizophrenia treatments all targeted the same chemical: dopamine. While that works for some, it causes brutal side effects for others. An antipsychotic drug approved last month by the FDA changes that. It triggers muscarinic receptors instead of dopamine receptors. The drug is the result of a chance scientific finding ... from a study that wasn't even focused on schizophrenia. Host Emily Kwong and NPR pharmaceutical correspondent Sydney Lupkin dive into where the drug originated, how it works and what it might shift for people with schizophrenia.Read more of Sydney's reporting.Curious about other drug treatments in the news? Email us at shortwave@npr.org and we might cover your topic on a future episode! Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Every American red wolf alive right now is descended from only 14 canids. In the 1970s, humans drove the red wolf to the brink of extinction. Because of that, red wolves today have low genetic diversity. But what if we could recover that diversity ... using "ghost genes"? That's right, today's episode is a ghost story. Along the way, we get into gene dictionaries, the possibilities of poo and how a photo of a common Texas coyote started it all.Have another animal you want us to dig into for a future episode? Email us at shortwave@npr.org!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Calling all foragers! The new board game Undergrove, co-designed by Elizabeth Hargrave and Mark Wooten, is all about the symbiotic relationships between trees and fungi. Players assume the role of mature Douglas fir trees and partner with mushrooms, which represent the mycorrhizal network. P.S. If the name "Elizabeth Hargrave" sounds familiar — she also designed the bird-collecting game Wingspan. Have another science-backed board game you'd like us to play? Email us at shortwave@npr.org!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

In the humid rainforests of northern and eastern Madagascar reside seven newly described frog species. They often hang out near fast, flowing rivers. These treefrogs' high-pitched, "futuristic" sounds may help male frogs attract females over the sound of nearby rushing water. They also are what inspired their Star Trek-themed names. Have another animal you want us to dig into for a future episode? Email us at shortwave@npr.org!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy