A strange brew that's hard to resist, even for a modern day microbe.

In the war on devilish microbes, our weapons are starting to fail us. The antibiotics we once wielded like miraculous flaming swords seem more like lukewarm butter knives. But in this episode, originally released in 2015, we follow an odd couple, of a sort, to a storied land of elves and dragons. There, they uncover a 1,000-year-old secret that makes us reconsider our most basic assumptions about human progress and wonder: what if the only way forward is backward?

Special thanks to Steve Diggle, Professor Roberta Frank, Alexandra Reider and Justin Park (our Old English readers), Gene Murrow from Gotham Early Music Scene, Marcia Young for her performance on the medieval harp and Collin Monro of Tadcaster and the rest of the Barony of Iron Bog.

Can’t get enough of that sweet, sweet antibiotic resistance content? Then you’ll be over the moon about next week’s release. It’s the podcast cut of our most recent installment of our live show series called Viscera. This one features executive editor Soren Wheeler and Avir Mitra, and it’s all about how our millenia's-long war against bacteria came to a tipping point in this modern age.

Subscribe or follow our show on your favorite streaming platform and you’ll be the first to know when it drops.

EPISODE CREDITS:
Reported by - Latif Nasser
Produced by - Matt Kielty and Soren Wheeler

EPISODE CITATIONS:
Articles -
Uncovering the multifaceted mechanism of action of a historical antimicrobial (https://zpr.io/mucw6Td6LBxT) by Harrison, F et al, 2026 bioRxv (PREPRINT). In this article Freya and her team describe the mechanisms under which Bald’s Remedy actually works.

Signup for our newsletter!! It includes short essays, recommendations, and details about other ways to interact with the show. Sign up (https://radiolab.org/newsletter)!

Radiolab is supported by listeners like you. Support Radiolab by becoming a member of The Lab (https://members.radiolab.org/) today.

Follow our show on Instagram, Twitter and Facebook @radiolab, and share your thoughts with us by emailing radiolab@wnyc.org.

Leadership support for Radiolab’s science programming is provided by the Simons Foundation and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.

In this episode, we consider a creature we often don’t think much about—the snail. And not just snails, but their sex lives. Which, as it turns out, is epic. There is persuasion and subterfuge, spaghetti penises and co-copulation. And this very surprising habit—erm kink—of making tiny arrows (actually!) and stabbing each other with them. Known as a “love dart,” these limestone daggers aren’t just a strange trick of nature—they have a deep evolutionary purpose.

Special thanks to Menno Schilthuizen and Aaron Chase.

EPISODE CREDITS:
Hosted by - Molly Webster
Reported by - Molly Webster
Produced by - Mona Madgavkar, Annie McEwen, Molly Webster
Sound design contributed by - Mona Madgavkar, Annie McEwen
Fact-checking by - Diane A. Kelly
and Edited by - Alex Neason

EPISODE CITATIONS:

Videos -
A love dart being DARTED! (https://zpr.io/rYhLwXhaxQQP) – Molly has watched this video so many times

Articles -

• Changes in the reproductive system of the snail Helix aspersa caused by mucus from the love dart. (https://zpr.io/xxjuCcTyiVJV) by Koene JM, Chase R. J Exp Biol.
• The snail's love-dart delivers mucus to increase paternity. By Chase R, Blanchard KC. Proc Biol Sci.
• A love-dart at the heart of sexual conflict in snails (https://zpr.io/X2ANHPaEg5sr) by Foote C
  ** This article has an image of eight different love darts, and it’s what Molly shows to Soren in the episode (this image is one of her favorite research finds!)

Books -
“Nature’s Nether Regions: What the Sex Lives of Bugs, Birds, and Beasts Tell Us About Evolution, Biodiversity, and Ourselves” (https://zpr.io/ktMvJbZciCdD) by evolutionary biologist Menno Schilthuizen.

Signup for our newsletter!! It includes short essays, recommendations, and details about other ways to interact with the show. Sign up (https://radiolab.org/newsletter)!

Radiolab is supported by listeners like you. Support Radiolab by becoming a member of The Lab (https://members.radiolab.org/) today.

Follow our show on Instagram, Twitter and Facebook @radiolab, and share your thoughts with us by emailing radiolab@wnyc.org.

Leadership support for Radiolab’s science programming is provided by the Simons Foundation and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.