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.

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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, first aired in 2014, we examine three very different kinds of black boxes—spaces where we know what’s going in, we know what’s coming out, but can’t see what happens in-between.

From the darkest parts of metamorphosis to a sixty-year-old secret among magicians, and the nature of consciousness itself, we shine some light on three questions. But for each, we contend with an answerless space, leaving just enough room for the mystery and magic, always wondering what’s inside the Black Box.

EPISODE CREDITS:
Reported by Tim Howard and Molly Webster
Produced by Tim Howard and Molly Webster

EPISODE CITATIONS:
Radio Show: ABC's Keep Them Guessing (https://tinyurl.com/9r9zmftr)

LATERAL CUTS:
Last year we shared a story on our feed about butterfly researcher Dr. Martha Weiss, and how she befriended a little boy on the other side of the world who wanted to do his own caterpillar memory study.

Martha’s daughter Annie Rosenthal captured the whole adventure on tape and produced a gorgeous audio feature, “Caterpillar Roadshow,” which was first published in the audio magazine Signal Hill.

You can find it on our feed (https://zpr.io/xPdAYXFUMr4s)
–or on Signal Hill’s website. (https://zpr.io/a4bjPKeXJQWK)

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

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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.

Before he was even born, Sarah and Ross Gray knew that their son Thomas wouldn’t live long. But as they let go of him, they made a decision that reverberated through a world that they never bothered to think about. Years later, after a couple of awkward phone calls, they go on a quest and manage to meet the people and places for whom Thomas’ short life was an altogether different kind of gift. We originally made this story back in 2015, but we wanted to play it again because we love that it brings a view of science that is redemptive, tender, and unexpected.

Since we first released this episode, Sarah Gray wrote a book called A Life Everlasting (https://zpr.io/GVYisRaqe9d6), it’s a memoir about Thomas that dives into the world of organ donation and medical science. She’s also written a beautiful short story about shame called The Lacemaker Fairy Tale (https://zpr.io/Li5BMtfHmf92). And, right now she’s working on a script for a movie called Raincheck.

EPISODE CREDITS:
Reported by - Jad Abumrad
with help from - Latif Nasser

LATERAL CUTS -

• The Cathedral (https://radiolab.org/podcast/cathedral)
• The Immortal Life of Henrietta Lacks (https://radiolab.org/podcast/the-immortal-life-of-henrietta-lacks)

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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 the early 2000s, Sunil Nakrani felt stuck.

Back then, websites crashed all the time. When Sunil noticed this, he decided he was going to fix the internet. But after nearly a year of studying the architecture of the web, he was no closer to an answer. In desperation, Sunil sent out a raft of cold emails to engineering professors. He hoped someone, anyone, could help him figure this out. Eventually, he learned that the internet could only be fixed if he paid attention to the humble honeybee.

This is the story of the Honeybee Algorithm: How tech used honeybees to build the internet as we know it.

Special thanks to John Bartholdi, John Vande Vate, Sammy Ramsey, James Marshall, Steve Strogatz, Duc Pham, and Heiko Hamann.

We found out about this story thanks to our friends at AAAS, who run the one and only Golden Goose Awards. The award goes to government funded science that sounds trivial or bizarre, but goes on to change the world. The Honeybee Algorithm won a Golden Goose Award back in 2016 (https://zpr.io/ePxaaYja6YF4). Thank you to our friends there: Erin Heath, Gwendolyn Bogard, Valeria Sabate, Joanne Padron Carney, and Meredith Asbury.

EPISODE CREDITS:
Reported by - Latif Nasser
with help from - Maria Paz Gutiérrez
Produced by - Maria Paz Gutiérrez, Annie McEwen and Pat Walters
and Edited by - Pat Walters

EPISODE CITATIONS:

Videos -

• Golden Goose Award video about 2016 winners (https://zpr.io/eXwTJKGL6F8S)

Books -

• The Wisdom of the Hive: The Social Physiology of Honeybee Colonies (https://www.hup.harvard.edu/books/9780674953765) by Thomas D. Seeley (1995, Harvard University Press)
• Piping Hot Bees & Boisterous Buzz-Runners: 20 Mysteries of Honey Bee Behavior Solved (https://zpr.io/tNDqkw372Rhr) by Thomas D. Seeley
• And, Paths of Pollen (https://zpr.io/cqRPpAdGRwMi) by Stephen Humphrey. One of our former transcribers who we recently learned had hidden talents far beyond the invaluable work they did for us. This book is only tangentially related to the content in the episode, but super cool in its own right.
  

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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 break the thermometer and watch the mercury spill out as we discover that temperature is far stranger than it seems. We first ran this episode in 2021: Five stories that run the gamut from snakes to stars. We start out underwater, with a species of snake that has evolved a devious trick for keeping warm. Then we hear the tale of a young man whose seemingly simple method of warming up might be the very thing making him cold. And Senior Correspondent Molly Webster blows the lid off the idea that 98.6 degrees Fahrenheit is a sound marker of health.

EPISODE CREDITS:
Reported by - Lulu Miller and Molly Webster
Produced by - Becca Bressler, Lulu Miller and Molly Webster
with help from - Carin Leong
Fact-checking by - Emily Krieger

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

One spring evening in 2024, a science journalist named Rachel Gross bombed at karaoke. The culprit was a bleed in a fist-sized clump of neurons tucked down in the back of her brain called the cerebellum. A couple weeks later, her doctors took a bit of it out, assuring her it was just helping her with motor coordination — she might be a bit clumsy for a while, but she’d still be herself. But afterwards, she didn't feel like herself. So she dove into the dusty basement of the brain (and brain science) to figure out why. What Rachel found was a burgeoning new frontier in neuroscience. We learn what singing Shakira on stage has to do with reaching for a cup of coffee — and how the surprising relationship between the two is making us rethink what we think about thinking.

Special thanks to Warzone Karaoke at Branded Saloon, Dr. Joanne Loewy and the Singing Together, Measure by Measure choir at the Louis Armstrong Center for Music and Medicine (http://musicandmedicine.org/) at Mount Sinai Union Square, Dag Spicer and the Computer History Museum, Désirée Lie, Mark Gross, Daniel A. Gross, Brittany Aguilar, and, of course, Shakira.

EPISODE CREDITS:
Reported by - Rachel Gross
Produced by - Sindhu Gnanasambandan

EPISODE CITATIONS:

Articles -

• “Ignoring the cerebellum is hindering progress in neuroscience.” (https://pubmed.ncbi.nlm.nih.gov/39934082/), by Wang et al, 2025
• “The cerebellum and cognition.” (https://pubmed.ncbi.nlm.nih.gov/29997061/), by Schmahmann JD. Neurosci Lett. 2019
• “How did brains evolve?” (https://pubmed.ncbi.nlm.nih.gov/11805823/), by Barton RA., Nature. 2002

Books -

• Vagina Obscura (https://www.rachelegross.com/book), by Rachel E. Gross

Sign up for our newsletter!! It includes short essays, recommendations, and details about other ways to interact with the show. Signup (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 Gordon and Betty Moore Foundation, Science Sandbox, a Simons Foundation Initiative, and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.

Most of us spend some part of our lives feeling bad about ourselves and wanting to feel better. But this preoccupation is a surprisingly new one in the history of the world, and can largely be traced back to one man: a rumpled, convertible-driving California state representative named John Vasconcellos who helped spark a movement that took over schools, board rooms, and social-service offices across America in the 1990s. This week, we look at the rise and fall of the self-esteem movement and ask: is it possible to raise your self-esteem? And is trying to do so even a good idea?

Special thanks to big thank you to the University of California, Santa Barbara Library for use of audio material from their Humanistic Psychology Archives and to their staff for helping located so many audio recordings.

EPISODE CREDITS:
Reported by - Heather Radke and Matt Kielty
Produced by - Matt Kietly
Original music and sound design by - Jeremy S. Bloom and Matt Kielty
Flute performance and compositions by - Ben Batchelder
Voiceover work by - Dann Fink and David Gebel
Mixing help by - Jeremy S. Bloom
Fact-checking by - Anna Pujol-Mazzini and Angely Mercado
and Edited by - Pat Walters

EPISODE CITATIONS:

Articles -

• UCSB Humanistic Psychology Archive (https://zpr.io/HfVjUmvcVevE)

Books -

• Selfie: How We Became So Self-Obsessed and What It's Doing to Us (https://zpr.io/eGRyqz9zNQHu) by Will Storr. Counterpoint, 2018.
• A Liberating Vision (https://zpr.io/tJn7BR5m84fv) by Vasconcellos, John. Impact Publishers, Inc., 1979
• The Therapeutic State (https://zpr.io/tJn7BR5m84fv) by Nolan, James, Jr. NYU Press, 1998

Sing up 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 Gordon and Betty Moore Foundation, Science Sandbox, a Simons Foundation Initiative, and the John Templeton Foundation. Foundational support for Radiolab was provided by the Alfred P. Sloan Foundation.