The World's Only Immortal Animal [You must be registered and logged in to see this link.]The
turritopsis nutricula species of Jellyfish has been
discovered to be the first, and possibly only,
immortal
creature. Once the creature reaches its adult form (pictured) it
can, apparently, use transdifferentiation to transform its cells
backwards to the polyp stage of its life and begin the whole cycle
again. There's not much more to say beyond that - consider myself
officially in awe.