Mola Mola are unique in several ways, including in their freakish appearance. Descended from porcupine fish, they have evolved into immense animals that appear to be a floating head with enlarged fins. They swim slowly with their mouths open. In fact, they are unable to close them at all. They are also incapable of quick propulsion. Primitive in their design, they have no means of defence except to dive deep to escape predators. They feed on squid, small fish, eggs and larvae, and even jellyfish. They move at a ridiculously slow speed, except in short bursts. They also lie flat on the surface of the water to sun themselves. They are a truly strange fish that is baffling to naturalists and biologists. There is a lot that scientists don't yet understand about these giants of the deep. Known to lay the most eggs of any vertebrate in the world, they can produce up to 300,000,000 at a time. They are the world's largest bony fish, reaching an incredible 2200kg (4700lbs). At full size, they have few predators, but they are vulnerable to almost any shark, orca or sea lion when they are growing. These fish often suspend themselves in an upright position to take advantage of cleaning stations, or areas where smaller wrasses rid larger animals of parasites on their bodies and around their mouths. Although they generally very shy and reclusive, they will sometimes allow a slow and cautious diver to approach them. The scuba diver with the camera is experiencing something very rare as the giant fish swims past him so close that it almost bumped him. Possibly curious, it seemed to inspect him closely as it went past.