A whale shark the size of a school bus swims slowly near the surface of the ocean. Its wide mouth is open, like an enormous net scooping up whatever happens to be around—mostly small fish, …

Meet the real "Nemo," the colorful clownfish. Find out how these fish can reproduce even though all their young are born male.

A shadowy shape is visible in the distance, just under the surface of the ocean. The shadow swims closer, revealing itself to be a shark—an incredibly massive shark. Weighing as much …

Sharks can rouse fear and awe like no other creature in the sea. Find out about the world's biggest and fastest sharks, how sharks reproduce, and how some species are at risk of …

A betta fish (Betta splendens) photographed in Lincoln, Nebraska. Also known as Siamese fighting fish, they originally hailed from Southeast Asia but are now popular pets found in …

Meet the newest ‘walking’ fish—a bright red creature of the deep This odd-looking sea toad may look like crochet. But it's one of a hundred species possibly new to science that have been ...

Fish are vertebrates (vertebrates have backbones) that live in water. They breathe using special organs called gills.

What is a blobfish? If you were asked to think of the ugliest creature you can imagine, you might picture the blobfish: a pale pink gelatinous blob with a droopy, downturned mouth and large ...

How to be a smart fish eater.Many kids turn up their noses at the thought of eating fish because, well, it can smell “fishy.” While it is usually a healthful source of protein in the diet, there may …

The blobfish went viral with this photo, but underwater they look like a completely different fish. They sustain tissue damage when they're brought from the ocean's depths to the surface.