Short Wave

Approximately 80% of orange cats are males, including the four orange cats owned by the Short Wave team. Scientists have long suspected that orange color was a sex-linked trait — hiding somewhere on the X chromosome. Now, scientists at Stanford University and Kyushu University in Japan have characterized the mutation responsible for orange cat coloration. Both groups published their results in the journal Cell Biology [https://www.cell.com/current-biology/fulltext/S0960-9822(25)00391-4] this week. Have a question about the animals all around us? Email us at shortwave@npr.org [shortwave@npr.org] — we'd love to hear from you! Listen to Short Wave on Spotify [https://n.pr/3HOQKeK] and Apple Podcasts [https://n.pr/3WA9vqh]. 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]

Most bats use echolocation to navigate and hunt, but some use their ears for another trick: eavesdropping. "And then these frog-eating bats, for example, they are actually listening in on the mating calls of frogs that are much, much lower in frequency," says behavioral ecologist Rachel Page. [https://stri.si.edu/scientist/rachel-page] But how the bats knew this eavesdropping trick was a mystery. So she set up and experiment with baby bats and a speaker. Have a question about the animals all around us? Email us at shortwave@npr.org [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 [http://plus.npr.org/shortwave]. 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]

Becoming fluent in a second language is difficult. But for adults, is it impossible? Science says no. In this encore episode, Short Wave host Emily Kwong [https://www.npr.org/people/767284140/emily-kwong] dissects the "critical period hypothesis," a theory which linguists have been debating for decades — with the help of Sarah Frances Phillips [https://sarahfphillips.com/], a Ph.D. student in the linguistics department at New York University. Together, Emily and former Short Wave host Maddie Sofia [https://www.madelinesofia.com/] explore where the theory comes from, how it applies to second-language acquisition and what it means for Emily's efforts to learn Mandarin Chinese as an adult. Have a linguistics or neuroscience question? Email us at shortwave@npr.org [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 [http://plus.npr.org/shortwave]. 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]

Today, we're airing an episode of NPR's daily economics podcast, The Indicator from Planet Money [https://www.npr.org/podcasts/510325/the-indicator-from-planet-money]. It's about a group of people we know well: scientists. President Trump's federal cuts and scrutiny of academic institutions are forcing some U.S. scientists to head for the border. On today's show, an entomologist keeping America's farms safe from pests reconsiders America. And a CEO of a Canadian hospital explains how they are benefiting from the exodus. Want to learn more about the intersection of science and the economy? Email us 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]. 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]

Google [https://sustainability.google/operating-sustainably/net-zero-carbon/], Microsoft [https://blogs.microsoft.com/blog/2020/01/16/microsoft-will-be-carbon-negative-by-2030/] and Meta [https://sustainability.atmeta.com/climate/]have all pledged to reach at least net-zero carbon emissions by 2030. Amazon [https://sustainability.aboutamazon.com/climate-solutions]set their net-zero deadline for 2040. To understand how these four tech companies could possibly meet their climate goals amid an artificial intelligence renaissance, Short Wave co-host Emily Kwong [https://www.npr.org/people/767284140/emily-kwong] discusses the green AI movement. Speaking with scientists, CEOs and tech insiders, she explores three possible pathways: nuclear energy, small language models (SLMs) and back-to-the-future ways of keeping data centers cool. Listen to Part 1 of Short Wave's reporting on the environmental cost of AI here [https://www.npr.org/2025/05/07/1249592906/energy-water-ai-climate-tech]. Have a question about AI and the environment? Email us at shortwave@npr.org [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 [http://plus.npr.org/shortwave]. 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]