Radiolab The Glow Below
122 snips
Oct 31, 2025 
Edie Widder, an accomplished oceanographer and expert in deep-sea bioluminescence, shares her fascinating experiences exploring the mysterious world beneath the waves. She discusses how creatures create and use light for hunting, camouflage, and communication. Edie reveals the overlooked importance of bioluminescence and explains the unique functions of light organs in species like anglerfish. With captivating anecdotes from her dives, she illustrates the profound interactions that occur in the dark depths, where light becomes a vital language of the ocean.
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Holding Dripping Deep-Sea Light
- Edie Widder describes pulling a bright red shrimp from cold water that squirted neon blue light which pooled in her hand and dripped between her fingers.
- She called the sensation "cold light" and found it revelatory, sparking decades of research into bioluminescence.
First Dive Into a Fireworks of Light
- On her first open-ocean dive in a WASP suit, Edie turned off the lights and found herself in a "fireworks display" of sparkles, glows, squirts, and clouds of blue bioluminescence.
- She was astonished by the sheer amount and variety of light surrounding her and how blue dominated because it travels farthest through seawater.
Light Is An Energetic Life Tool
- Edie explains bioluminescence is energetically costly, so animals use it for crucial functions like finding food, mating, defense, and camouflage.
- Counter-illumination matches belly light to downwelling sunlight intensity and can change quickly to remain invisible.