12/08/2025

Don’t Let Their Name Fool You—Sea Slugs Are Awesome

Today we’re spotlighting an underappreciated group of marine creatures: sea slugs. Don’t let their humble name fool you. They come in vivid neon colors, with patterns that rival the most beautiful butterflies and feather-like external gills and tentacles.

There are an estimated 10,000 species of sea slugs and they are incredibly diverse. Some are smaller than a quarter. And one species can weigh more than a terrier, up to 30 pounds. Not to mention their contributions to brain research—understanding their neural networks was the basis for a Nobel Prize in 2000.  

Marine biologist Patrick Krug joins Host Ira Flatow to dive into the slimy science of sea slugs. 


Watch a video of a detached sea slug head regrowing an entirely new body.


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Segment Guests

Patrick Krug

Dr. Patrick Krug is a sea slug researcher and professor of biological sciences at Cal State LA.

Segment Transcript

The transcript is being processed. It will be available 2-3 days after this story’s publication date.

Meet the Producers and Host

About Shoshannah Buxbaum

Shoshannah Buxbaum is a producer for Science Friday. She’s particularly drawn to stories about health, psychology, and the environment. She’s a proud New Jersey native and will happily share her opinions on why the state is deserving of a little more love.

About Ira Flatow

Ira Flatow is the founder and host of Science FridayHis green thumb has revived many an office plant at death’s door.

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