THE IMMORTAL JELLYFISH
No bigger than a human pinky, Turritopsis dohrnii, commonly referred to as the immortal jellyfish, possesses the baffling ability to live forever – that is, until a predator pounces.
1 All jellyfish exist in two forms: polyp form and medusa form. While most grow from polyp to medusa, the immortal jellyfish can alternate between both forms
2 Like all jellyfish, it has no brain nor heart
3 The immortal jellyfish reproduces both sexually and asexually. When at the brink of death, the immortal jellyfish can revert back to the polyp stage and start its life cycle all over again. Fortunately, there is no limit to the number of times they can do this!
4 This ability is achieved through a rare process called transdifferentiation: the action of a mature, specialised cell transforming into a completely different mature, specialised cell. Scientists have been studying this cellular mechanism for its potential use in medicine
5 Despite being discovered way back in 1883, the special ability of this species was only realised in the mid-1990s
6 Scientist Shin Kubota, who has spent more than 15 years studying these organisms at Kyoto University’s Seto Marine Biological Laboratory, found that certain conditions prevent reinvigoration: starvation, large bell size and water colder than 22 degrees Celsius
7 Immortal jellyfish are also known to be “hitchhikers”. They have been recorded hitching rides on cargo ships that use seawater for ballast. This phenomenon has allowed the species to rapidly populate the world’s oceans in recent decades
APPEARANCE: This jellyfish has a bright-red stomach, seen in the middle of its transparent bell. Its edges are lined with 80 to 90 white tentacles, though given its small size, they are barely visible.
CLASS: HydrozoaOTHER NAMES: Medusa, benjamin button jellyfishDISTRIBUTION: Originating from the Mediterranean Sea, this unique creature has spread all over the world, and can now be found in both temperate and tropical regions, though it prefers warmer watersSIZE: Up to 4-5 millimetres tall and wide