There exists a species of copepods, or parasites, unique to Greenland Sharks. These small critters latch onto their eyeballs for the duration of their life. The constant rubbing against the surface of the shark’s eye renders them blind. Lucky for the sharks, they spend a lot of time in the deep dark ocean, so sight isn’t essential for their survival. Their lack of sight may explain why they move incredibly slow.

Think sloth speed but with less reaction time. “It takes five seconds for a Greenland Shark to react,” according to Dr. Peter G. Bushnell, Professor of Biological Sciences at Indiana University South Bend. Despite their slow speeds and blindness these sharks continue to amaze scientists. They are active predators, and not just bottom feeders like scientists had assumed for years.

Cod, seal, reindeer, and even polar bear fur has been found inside the stomach of Greenland Sharks. There is a lot of mystery as to how they find their prey. Scientists speculate that they are the most patient hunters in the ocean, and can sneak up on prey under the dark sea-ice.