Return of the Flesh-Eaters

Mar 13, 2026 · 42 min

About this episode

If a species is horrible enough, do we have the right to kill it forever? Seventy years ago, a nightmare parasite feasted on the live flesh of warm-blooded creatures in North America: the screwworm. That is, until a young scientist named Edward F. Knipling discovered a crucial screwworm weakness and hatched a sweeping project to wipe them out. Knipling’s seemingly zany plan to spray screwworms out of planes all over the continent— with US taxpayer money— succeeded, becoming one of humanity’s biggest environmental interventions ever. Today, screwworms have been gone so long that none of us in North America even remember them. But now, they’re coming back. And they’re forcing us to ask: in an era of climate change and rapid mass extinction— should we kill off a species on purpose? Special thanks to James P. Collins, Max Scott, Amy Murillo, Daniel Griffin, Phil Kaufman, Katie Barnhill, Arthur Caplan, Ron Sandler, Yasha Rohwer, Aaron Keefe, Gwendolyn Bogard, Maria Sabate, Meredith Asbury, and Joanne Padrón Carney EPISODE CREDITS: Reported by - Sarah Qari with help from - Latif Nasser Produced by - Sarah Qari Sound design contributed by - Sarah Qari Fact-checking by - Emily Krieger EPISODE CITATIONS: **The latest information on screwworm outbreaks and precautions: <a href="http://screwworm.gov" rel="noopener noreferrer">screwworm.gov</a> Videos: <ul> <li>Oral history interviews of Edward F. Knipling: <a href="https://archive.org/details/cat31344919" rel="noopener noreferrer">here</a> (https://zpr.io/njhMedFN5jsZ) and <a href="https://archive.org/details/cat31344920" rel="noopener noreferrer">here</a> (<a href="https://zpr.io/VQReQbfznCrq" rel="noopener noreferrer">https://zpr.io/VQReQbfznCrq</a>) </li> </ul> Podcasts: <ul> <li>Here’s a <a href="https://open.spotify.com/playlist/5sgSHHB3LuubU4cXzKd2ze?si=R8gh-yUZSGamXKqGlE7dZg" rel="noopener noreferrer">Spotify playlist</a> (<a href="https://zpr.io/PNMEM274G7vh" rel="noopener noreferrer">https://zpr.io/PNMEM274G7vh</a>) of all of our Golden Goose-inspired episodes!</li> <li>Sam Kean’s podcast The Disappearing Spoon – his episode about screwworms is called <a href="https://www.sciencehistory.org/stories/disappearing-pod/the-screwiest-and-perhaps-most-original-idea-of-the-20th-century/" rel="noopener noreferrer">The Screwiest and Perhaps Most Original Idea of the 20th Century</a> (<a href="https://zpr.io/UYf6dR2yG3eN" rel="noopener noreferrer">https://zpr.io/UYf6dR2yG3eN</a>) </li> <li>Our episode on <a href="https://radiolab.org/podcast/update-crispr" rel="noopener noreferrer">CRISPR & gene drives</a> (<a href="https://zpr.io/UYf6dR2yG3eN" rel="noopener noreferrer">https://zpr.io/UYf6dR2yG3eN</a>) </li> <li>New to Radiolab? Check out our <a href="https://open.spotify.com/playlist/7eoEmqGP7vWRyTfc9ncLDh?si=f8ebfc13b5f443d2" rel="noopener noreferrer">Radiolab Starter Kit</a> (<a href="https://zpr.io/QpPnrHAZVQLR" rel="noopener noreferrer">https://zpr.io/QpPnrHAZVQLR</a>) playlist of all-time favorite episodes!</li> </ul> Articles: <ul> <li>Sarah Zhang’s latest piece in The Atlantic: <a href="https://www.theatlantic.com/science/2026/02/americas-cows-milkfat/685881/" rel="noopener noreferrer">American Milk Has Changed</a> (<a href="https://zpr.io/xebbdq2MWV4L" rel="noopener noreferrer">https://zpr.io/xebbdq2MWV4L</a>) </li> <li>Her most recent piece on screwworms: <a href="https://www.theatlantic.com/science/archive/2025/05/screwworms-outbreak-united-states/682925/" rel="noopener noreferrer">The ‘Man-Eater’ Screwworm Is Coming</a> (<a href="https://zpr.io/ECmjCs7ScbS4" rel="noopener noreferrer">https://zpr.io/ECmjCs7ScbS4</a>) </li> <li>Her initial reporting on screwworms: <a href="https://www.theatlantic.com/science/archive/2020/05/flesh-eating-worms-disease-containment-america-panama/611026/" rel="noopener noreferrer">America’s Never-Ending Battle Against Flesh-Eating Worms</a> (<a href="https://zpr.io/PNMEM274G7vh" rel="noopener noreferrer">https://zpr.io/PNMEM274G7vh</a>) </li> <li>Gregory Kaebnick’s <a href="https://www.science.org/doi/10.1126/science.adv4045" rel="noopener noreferrer">paper</a> (<a href="https://zpr.io/yqNC3q5FbCcq" rel="noopener noreferrer">https://zpr.io/yqNC3q5FbCcq</a>) about screwworm eradication in Science</li> </ul> Archival materials: <ul> <li>The USDA’s <a href="https://www.nal.usda.gov/exhibits/speccoll/items/browse?collection=31&sort_field=Dublin+Core%2CIdentifier&sort_order=desc&page=1" rel="noopener noreferrer">Screwworm Eradication Records</a> (<a href="https://zpr.io/dY7zuVdGYKjf" rel="noopener noreferrer">https://zpr.io/dY7zuVdGYKjf</a>) contain lots of cool images and letters</li> </ul> Signup for our newsletter!! 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