"To our knowledge, this species has never been observed in the wild." Researchers celebrate after capturing video of shark ...

The creatures cruised the world’s oceans with features we often associate with marine mammals, such as coats of blubber and ...

The Greenland shark is a slow-moving giant with an unbelievable lifespan—some living for over 400 years. Its biology is as bizarre as its icy, deep-sea home.