Vampyroteuthis infernalis—the infernal vampire squid—has the largest eyes in proportion to body size in the world. A 6-inch specimen will sport eyes the size of a large dog's.

The Amazonian hatchetfish can flap its pectoral muscles like wings and fly for short distances.

The leaf fish looks like a dead leaf and also acts like one: Most of its time is spent motionless at the bottom of a river.

The frog-fish is the fastest eater in the ocean. It takes 6 milliseconds for it to open its mouth, swallow, and close.