Killer Whales Taking over the World.

[Lost]

I'd say the Immortal Jellyfish is taking over the world, too. The Immortal Jellyfish theoretically cannot die from age, as it reverts back to a polyp form when it reaches sexual maturity. According to biologists, the recent population explosion of Jellyfish worldwide is due directly to the Immortal Jellyfish. It doesn't help that they don't really have a natural predator, either.