'Benjamin Button' Jellyfish Are Immortal

For some aging jellyfish, their best years may still be ahead: Faced with a threat, one species can essentially turn itself younger again, National Geographic reports. Turritopsis dohrnii reverts its cells to a “younger state,” says a researcher, and becomes a blob; from there, it develops into a colony reminiscent of its younger self. That colony can then asexually reproduce copies of the original, rendering it “immortal.”

Turritopsis has lately been swarming the world’s oceans, and oddly, specimens found in one area of the world are genetically identical to those from another. Scientists think the jellyfish are hitching a ride on boats rather than spreading via currents. The creature’s ability to “switch off some genes and to switch on” others could give clues to fighting cancer, notes a biologist. (More The Curious Case of Benjamin Button stories.)