They may be found in every ocean on Earth, but jellyfish are still some of the most mystifying creatures in the world. Often underestimated, these animals harbor some of nature's most innovative adaptive techniques - here are a few facts you may not know about jellyfish.
The Turritopsis dohrnii is an infamous example of nature working magic. There are two main phases in the development of a jellyfish: the first being the stationary polyp stage where they are attached to the sea floor and the second being the mobile medusa stage. The immortal jellyfish, found in the Mediterranean and off the coast of Japan, is unique in that it is the only animal known to be able to revert back to its immature state after having reached maturity. This process can be triggered by environmental stress, old age, sickness or injury, and renders the T. dohrnii biologically immortal.
They don't have brains or lungs.