Do jellyfish hold the secret to immortality, and a cure for cancer? Xeni Jardin, boingboing.net Nathaniel Rich on the so-called “immortal jellyfish,” Turritopsis dohrnii: “[It] 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 li… RT @BoingBoing: Do…