If the T. dohrnii jellyfish is exposed to environmental stress, physical assault, or is sick or old, it can revert to the polyp stage, forming a new polyp colony.

A closeup shot of a glowing blue jellyfish in black water. One species stands out for its extraordinary ability: Turritopsis dohrnii, also known as the immortal jellyfish. This fingernail-sized ...

Jellyfish mortality rates and lifespans vary widely. Some species live only a few hours, others a few months or a few years — ...