Zombie Jellyfish

Can a Jellyfish Unlock the Secret of Immortality?

A species that can transform itself back to a polyp at any time appears to debunk the most fundamental law of the natural world — you are born, and then you die.
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We also know that, in recent decades, the immortal jellyfish has rapidly spread throughout the world’s oceans in what Maria Pia Miglietta, a biology professor at Notre Dame, calls “a silent invasion.” The jellyfish has been “hitchhiking” on cargo ships that use seawater for ballast. Turritopsis has now been observed not only in the Mediterranean but also off the coasts of Panama, Spain, Florida and Japan. The jellyfish seems able to survive, and proliferate, in every ocean in the world. It is possible to imagine a distant future in which most other species of life are extinct but the ocean will consist overwhelmingly of immortal jellyfish, a great gelatin consciousness everlasting. 

A real medical mystery.  Fascinating.