There is a genus of jellyfish that don't die of old age because they can revert to juvenile form after aging: https://en.wikipedia.org/wiki/Turritopsis_nutricu

There is a genus of jellyfish that don't die of old age because they can revert to juvenile form after aging: https://en.wikipedia.org/wiki/Turritopsis_nutricula https://en.wikipedia.org/wiki/Turritopsis_nutricula