Glittery sea worms and sea squirts fit for "The Lord of the Rings" universe might sound like pure fantasy, but they're very real creatures living in the deep sea. Some of these otherworldly ocean ...

The ocean is still one of the biggest mysteries on Earth, and the deeper you go, the stranger it gets. Far below the surface, ...

Find out what fossils have revealed about ichthyosaurs, which included the biggest marine reptile that ever lived.

In an age of exhausting AI-generated videos and manipulated images purporting to showcase real marine life that have never been seen by human eyes, it's easy to forget that there are actually ...

Thousands of meters below the ocean's surface lurk some gigantic creatures, much larger than their shallow-water brethren. Scientists have a few hunches for why this happens, but the debate continues.

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Although the apple ...

This secretive native of both sides of the Caribbean—from Belize to the British Virgin Islands—hides out on ledges and in caves of reefs up to 140 feet below the surface of the sea. Although not being ...