For illustration only.

Osedax

If you need even more proof of the horrors of the deep, consider the zombie worm, which feeds off the bones of whales and other scavenged sea creatures … despite not having a mouth. In July 2012, researchers at the Society for Experimental Biology's annual meeting announced that they'd figured out how this mouthless creature eats bone. It excretes acid.

The acids allow the worms to break down and absorb the bone, the researchers explained. But that's just the tip of the weirdness iceberg for these amazingly adapted worms. The females grow about an inch (3 cm) long, but males never grow larger than 1/20th of an inch (1 millimeter). They seem to live in the gelatinous tubes covering the females, serving no purpose but to fertilize her eggs.