Engulfed in a stinking fog, the bizarrely-shaped giant worm is large enough to consume a human. Though this predator is not based on any real creature, its extending proboscis exists in marine ragworms, which are active predators. We do know this: in Earth’s very early history, life first evolved in the absence of oxygen. The organisms produced so much of the gas as a waste product that they poisoned their own atmosphere, and oxygen-breathing ones eventually took their place. Still, it’s very unlikely that giant carnivorous worms were ever a reality; as far as we know, these early organisms were nearly all bacteria.