Sea Walnuts Reverse Aging: Meet the 'Benjamin Button' Jellyfish

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Walnut of Youth

Sea walnuts can age in reverse. Also known as Mnemiopsis leidyi, the comb jellyfish revert to a larval stage under stress.

• Shrink and revive when stressed

• Born-again walnuts grow larval tentacles to catch food

• Retain cellular identity throughout age-traversal

This is likely how M. leidyi survived stowing away in ships to become an invasive species in parts of Europe and Asia. Sea walnuts join immortal jellyfish and a tapeworm species on the short list of known age-travelling organisms. “Benjamin Button” of the sea.

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