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/adchoicesNPR 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!Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR 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/adchoicesNPR 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/adchoicesNPR 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/adchoicesNPR 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/adchoicesNPR 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/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