Most iguanas are indigenous to the Americas. So how did the Fijian species end up on the island, nearly 5000 miles away in the South Pacific? According to a new study in the journal PNAS, it was probably via raft ... that is, on clump of floating trees. And this rafting hypothesis isn't entirely unprecedented. After hurricanes Luis and Marilyn hit the Caribbean in the 1990s, researchers found that a group of iguanas had floated over 180 miles away from Guadeloupe to the territory of Anguilla. Want to hear more about iguanas? Or rafts? Or evolutionary 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/adchoicesNPR Privacy Policy

It seems like artificial intelligence is everywhere in our virtual lives. It's in our search results and our phones. But what happens when AI moves out of the chat and into the real world? NPR science editor and correspondent Geoff Brumfiel took a trip to the Intelligence through Robotic Interaction at Scale Lab at Stanford University to see how scientists are using AI to power robots and the large hurdles that exist for them to perform even simple tasks.Read Geoff's full story. Interested in more AI stories? Email us your ideas at shortwave@npr.org.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

What are the narwhals up to? Generally, we don't really know! They are mysterious creatures. NPR science correspondent Nell Greenfieldboyce talks about new, rare drone footage scientists captured of arctic narwhals. The video sparked new ideas for how they use their tusks.Read Nell's full piece.Love mysterious critters and want to hear more? Email us at shortwave@npr.org.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Microalgae are tiny organisms that convert energy from sunlight into fuel. The arctic ecosystem depends on them. In springtime, the algae bloom brilliant shades of green and draw tiny crustaceans, fish, birds and more to arctic waters. But what happens in wintertime, when the sun goes down and darkness reins for months? In the depths of the polar night, biogeochemist Clara Hoppe has found evidence that some microalgae are still ready to photosynthesize. Today on the show: how tiny microalgae limbo for their lives and come out more powerful than scientists ever imagined. Want to hear more stories of nature pushing the boundaries of what scientists previously thought possible? Let us know 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

Baseball season is nigh! From Yankee stadium in New York to Dodger stadium in Los Angeles, teams around the country will face off Thursday to mark the start of the 2025 MLB 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. In this encore episode, 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

Early in the beginning of the COVID-19 pandemic, scientists predicted the SARS-CoV-2 virus would mutate slowly. They were wrong. Hundreds of thousands of viral mutations and multiple seasonal waves later, we now know why. The answer changes researchers' understanding of viral evolution — and it could help predict the evolution of other viruses in the future. Emily talks about it all with Sarah Zhang, a health writer for The Atlantic. Want to hear more virology or human biology stories? Let us know by emailing shortwave@npr.org.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy

Ever diagnosed yourself with a mental health disorder based on a TikTok video? If so, you're not alone. "I personally don't think that there's anything more human than wanting to understand yourself and wanting to understand your own experiences," says Vasileia Karasavva. Vasileia is the lead author of a paper published Wednesday in the journal PLOS One that gets into why this kind of self-diagnosis can be such a double-edged sword.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

Ever scan the ingredient list of your favorite personal care products like shampoos or lotions and think, what are these complicated chemicals? And are any of them bad for me? We definitely have. And our colleagues at NPR's Life Kit did one step better: They parlayed their anxiety spiral into a helpful guide on the safety of personal care products. So today, Gina talks to Life Kit's Marielle Segarra about some of the top chemicals of concern, including parabens and phthalates.Click here to hear the full Life Kit guide — including how to audit your go-to products.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

Measles is one of the most contagious infectious diseases known to science – more contagious than Ebola, smallpox or COVID-19. Declining vaccination rates over the past few years, plus a recent outbreak in West Texas, have public health experts concerned. Here's what to know about the science of this virus — plus how to protect against it. For the latest, host Regina G. Barber talks to NPR health correspondent Maria Godoy.Interested in other stories about public health? Tell us what you want to hear about 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

What if we had the ultimate work-life balance? This fundamental question underlies the hit Apple TV+ show Severance – now in its second season. Ahead of the season 2 finale this Friday, producer Rachel Carlson sat down with the science consultant for the series, Dr. Vijay Agarwal. Vijay says the concept is "resoundingly" possible – and that scientists closer than we might think. More questions about the intersections of pop culture and 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/adchoicesNPR Privacy Policy