Short Wave

What crocodile bones teach us about dinosaurs

Paleontologists have often determined how old a dinosaur was by counting the growth rings in its bones. Just like with trees, it was thought that each ring corresponded to a single year of age. But researchers who studied crocodiles at an outdoor recreation center near Cape Town appear to have poked a hole in that approach. In the crocodiles, which are some of the closest living relatives of dinosaurs, there was more than one growth ring laid down per year. The results contribute to a growing debate over the best way to age animals. Read more of freelance science reporter Ari Daniel’s story here [https://www.npr.org/2026/01/17/g-s1-106007/hiv-vaccine-trial-south-africa]. Interested in more on the future of science? Email us your question at shortwave@npr.org [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 [http://plus.npr.org/shortwave]. To manage podcast ad preferences, review the links below: See pcm.adswizz.com [https://pcm.adswizz.com] for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]

Teen sleep is getting wrecked by more than just phones

Teens aren’t getting enough sleep! And a two-decade study suggests it’s getting worse. Scientists found that the number of high schoolers getting insufficient sleep — less than seven hours a night — has increased from 69% to 77%. The throughline? There wasn’t one. Teens had bad sleep habits across most demographics, including race, gender and grade level. The findings were published [https://jamanetwork.com/journals/jama/article-abstract/2845759] this week in the journal JAMA. Interested in more science behind recent headlines? Email us your question at shortwave@npr.org [shortwave@npr.org]. For more about earthquake science – and the Cascadia Fault in particular – check out our recent episode on the Pacific Northwest’s Big One [https://www.npr.org/2025/11/25/nx-s1-5607262/oregon-japan-earthquake-pacific-northwest]. 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 [http://plus.npr.org/shortwave]. To manage podcast ad preferences, review the links below: See pcm.adswizz.com [https://pcm.adswizz.com] for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]

The global fallout of RFK Jr.'s vaccine policies

In his role as secretary of Health and Human Services, Robert F. Kennedy Jr. is changing how the United States approaches vaccines. But those changes aren’t limited to the United States. NPR global health correspondent Gabrielle Emanuel [https://www.npr.org/people/470414236/gabrielle-emanuel] joins Short Wave to talk about two examples of how the global public health landscape may be shifting. First, the United States’ ultimatum to an international vaccine group. Second, the uncertain fate of a vaccine trial. Some researchers are calling the trial a “unique” opportunity, and others are calling it “unethical.”  Read more of global health correspondent Gabrielle Emanuel’s work here [https://www.npr.org/people/470414236/gabrielle-emanuel]. Interested in more global health? Email us your question at shortwave@npr.org [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 [http://plus.npr.org/shortwave]. To manage podcast ad preferences, review the links below: See pcm.adswizz.com [https://pcm.adswizz.com] for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]

Will Punch the baby monkey be okay?

If you’ve been on the internet in the past few weeks, chances are you’ve seen him: a tiny gray-brown monkey dragging a big, stuffed orangutan around Japan’s Ichikawa Zoo. His name? Punch-kun, or Punch for short. His story? Early abandonment by his mother, careful treatment from local zookeepers and instant social media fame. But are all the (human) primates jumping to Punch’s defense justified? And what’s normal for Japanese macaque society, anyway? To find out, NPR’s Katia Riddle [https://www.npr.org/people/1128948946/katia-riddle] chats with psychology professor and animal expert Lauren Robinson [https://www.drlaurenrobinson.com/]. Interested in more animal science? Email us your question at shortwave@npr.org [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 [http://plus.npr.org/shortwave]. To manage podcast ad preferences, review the links below: See pcm.adswizz.com [https://pcm.adswizz.com] for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]

Spring ice is thawing earlier in lakes. What does that mean for life below the surface?

Lakes are freezing later, thawing earlier and experiencing dramatic temperature swings in between. And all that throws off the delicate balance of life below the surface. And that has a major impact on the roughly 1.7 million ice fishers in the U.S. who spend millions of dollars buying equipment and guide services each year. Producer Berly McCoy [https://www.npr.org/people/985775371/berly-mccoy] explains how scientists are tracking those ecological changes by getting out on the ice — to fish.  Interested in more freshwater science? Email us your question at shortwave@npr.org [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 [http://plus.npr.org/shortwave]. To manage podcast ad preferences, review the links below: See pcm.adswizz.com [https://pcm.adswizz.com] for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences. Learn more about sponsor message choices: podcastchoices.com/adchoices [https://podcastchoices.com/adchoices] NPR Privacy Policy [https://www.npr.org/about-npr/179878450/privacy-policy]