@.extremenature: The Jellyfish Smaller Than a Fingernail That May Have Never Died (Immortal Jellyfish) When injured, starving, or old — it doesn't die. It starts over. The immortal jellyfish reabsorbs its own body and reverts to an earlier life stage. The mechanism is called transdifferentiation — cells don't reset, they change identity entirely. Muscle becomes nerve. Skin becomes muscle. No other multicellular animal does this. Every individual alive today may be the same individual cycling for thousands of years. Ageing, in this species, is not terminal. It is reversible. Did you know there is an animal with no known biological process that forces it to die? Follow for more creatures built for extremes. #OceanScience #MarineBiology #ImmortalJellyfish #Educational #NatureDocumentary