Turritopsis dohrnii: The Jellyfish That Grows Young Again

An adult *Turritopsis dohrnii* can be injured or starved, then rebuild itself into its juvenile form—but is this “immortal jellyfish” truly cheating death? Explore life-cycle reversal, transdifferentiation, biological immortality, and what this tiny ocean animal may reveal about aging and regeneration before its strangest secret slips back into the deep.

Turritopsis dohrnii—the “immortal jellyfish”—can respond to injury, starvation, or environmental stress by reverting from its adult medusa stage to a juvenile polyp. This episode explores how life-cycle reversal and transdifferentiation work, why “immortal” does not mean invulnerable, and what this tiny hydrozoan may reveal about aging and regeneration. ([nhm.ac.uk](https://www.nhm.ac.uk/discover/immortal-jellyfish-secret-to-cheating-death.html?utm_source=openai))

Key takeaways

• An adult jellyfish can reorganize into an earlier life stage.

• The renewed polyp can bud genetically identical medusae.

• Biological immortality means avoiding senescence—not escaping predators, disease, or injury.

• DNA repair, telomere maintenance, and cell-state flexibility may help explain rejuvenation. ([pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/36037356/?utm_source=openai))

Chapters

The adult that becomes a polyp

How transdifferentiation rebuilds the body

Why “immortal” needs an asterisk

What jellyfish can teach aging research