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An immoratl jellyfish. Credit: Mother Nature Network
Stress can cut years from our lives. But for a tiny jellyfish-like organism, it’s just the opposite. Stress actually makes it age backwards — and eventually revert to its earliest stage of life. That provides a sort of immortality, as the organism produces a whole bunch of identical copies of itself.
The organism is known as Turritopsis. It was discovered in the 1880s in the Mediterranean Sea. Since then, it’s hitchhiked around the world in the ballast water of ships.
At first, Turritopsis seemed unremarkable. In its adult form, known as a medusa, it looks like a jellyfish that’s about the size of the nail on your little finger — not much to get excited about. But in the 1990s, scientists reported that when life got too stressful — from injury, lack of food, or even old age — the little critters could reverse the aging process. Their cells revert to a younger state, and can even change function — a muscle cell can become a skin cell, for example.
The process begins with the creature’s bell-shaped body turning inside out. Next, its tentacles and a layer of tissue shrivel up and vanish. It turns into a gelatinous mass, which develops a hard shell. Soon, this blob sprouts branches, which grow new juvenile forms of the organism, known as polyps. After a few days, the polyps begin to feed, then they drift away to form new medusas — which are genetically identical to the original. This process can happen over and over again — providing “immortality” for some tiny, stressed out creatures.
