Here's why:
* Bony fish (Osteichthyes) make up the largest class of vertebrates, with over 30,000 known species.
* Cartilaginous fish (Chondrichthyes), which include sharks, rays, and chimaeras, have only about 1,000 species.
Therefore, bony fish vastly outnumber cartilaginous fish, making them the dominant group in the fish world.