AnimalsMarine Life
One jellyfish can age backwards. Indefinitely.
The jellyfish Turritopsis dohrnii can respond to injury or starvation by reversing its own development, collapsing into a blob and reverting to its juvenile polyp form before growing up again. Its cells convert from one type to another, and in principle the cycle can repeat indefinitely — though in practice most are simply eaten.
Step by step
- Injured or starving, Turritopsis dohrnii doesn't have to die.
- The adult collapses into a blob and reverts to its juvenile polyp stage, then regrows.
- Its cells convert from one type to another; in principle the loop can repeat forever.
- In practice, most get eaten. Immortality does nothing about predators.
Source
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