Immortal jellyfish are strange and interesting animals, native to tropical waters. While they age in a linear process from tiny, fingernail-sized larvae to full-bodied adults with tentacles reminiscent of Medusa’s serpentine waves, their life cycle is quite different from that of other terrestrial creatures.
Sometimes when another jellyfish is stressed enough to shrug off its mortal coil, the immortal jellyfish simply reverses its life cycle, reverts back to its larval state, and gives birth to a set of tiny stems, essentially restarting their life from scratch.