Swim along the edge of a coral reef and you'll often see schools of sleek, torpedo-shaped fishes gliding through the currents ...

The boxfish is aptly named for its box-like shape. Covered in a bony carapace, this fish has a square, rigid body that gives it a distinctive appearance. Its body is often brightly colored ...

Judges and buyers pay attention to how healthy its skin looks, its size and body shape, and how gracefully the fish moves in the water. But the most important trait of all is the koi's coloring.

Once dubbed the world's ugliest animal for its soft, lumpy appearance, the blobfish has made a stunning comeback: it was crowned this week as Fish of the Year by a New Zealand environmental group. The ...

Fish like roach that migrate between lakes and streams have larger eyes with bigger pupils, improving vision in low light.

Ever since Charles Darwin, scientists have assumed species facing the same problem often evolve similar traits. But that’s ...

Swim along the edge of a coral reef and you’ll often see schools of sleek, torpedo-shaped fishes gliding through the currents, feeding on tiny plankton from the water column. For decades, scientists ...