One jellyfish can turn itself young again.

When injured or stressed, Turritopsis dohrnii can turn back into an earlier life stage and start over. In theory it can do this again and again.

Truth label: Established. Strong evidence and broad agreement among experts.

Go deeper

Not truly immortal

It still gets eaten and catches diseases. But ageing alone does not have to end it.

Learn

1. Running life backwards. The adult reverts to a blob-like polyp, which then grows into a fresh colony of jellyfish.

Test yourself

Sources

• Turritopsis dohrnii overview

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