The Glow Below | Radiolab Podcast @Radiolabpod

Uploaded November 2025 | Updated September 2026, 2 weeks ago

From the Radiolab podcast: A story of light that sparkles and glows, drips and squirts. And—maybe—talks.

A call to oceanographer Edie Widder about a fish with a very odd immune system quickly becomes something else: a dive into the deep sea, into a world of brilliant light. But down there, the light doesn’t behave like light—it sparkles and glows, but also drips, squirts, and dribbles. Today, find out how creatures make the light and how they use it, from hunting and hiding to maybe even … talking. And hear about a series of mysterious moments where Edie goes from studying the creatures to becoming one of them.

EPISODE CREDITS:
Hosted by Molly Webster
Reported by Molly Webster
Produced by Maria Paz Gutiérrez
with help from Molly Webster
Fact-checking by Diane A. Kelly

EPISODE CITATIONS:

Documentary-
Coming soon, there’ll be a new doc about Edie’s life and work studying bioluminescence in deep sea creatures. According to Edie, “A Life Illuminated”, contains some of the best deep sea bioluminescence footage ever recorded. It’s from our friends at Sandbox Films, and director Tasha Van Zandt.
sandboxfilms.org/films/a-life-illuminated

Books -
Edie Widder wrote a memoir! Go read, “Below the Edge of Darkness: A Memoir of Exploring Light and Life in the Deep Sea”.
penguinrandomhouse.com/books/564185/below-the-edge-of-darkness-by-edith-widder-phd

Videos -
It’s not in the episode, but a few years back, Edie’s fame reached new heights when she captured footage of a never-before-seen Giant Squid … here’s the story, and video.
youtube.com/watch?v=krDdv9KLmuM

Articles -
A look at some glowing shrimps.
zpr.io/3jyHWi7VFBw5

A photo gallery of different types of deep sea glow, from different types of deep sea creatures, including one of counterillumination, which Edie talks about in the episode.
zpr.io/hdFFsArGjhau

Episode Segments:
0:00 Intro

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Photo illustration by Jared Bartman
Video by W. Harry Fortuna

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