Which shark has a hammer-shaped head?

The shark with a hammer-shaped head is the hammerhead shark. Its flattened, sideways-extending head is called a cephalofoil, giving the animal its unmistakable T-shaped or hammer-like appearance.

Hammerheads are not one species but a family of sharks, Sphyrnidae. Most belong to the genus Sphyrna, including the great hammerhead, scalloped hammerhead, smooth hammerhead, and bonnethead. The winghead shark is the only member of its own genus, Eusphyra.

The unusual head may improve the shark’s vision, depth perception, maneuverability, and ability to detect prey using electroreceptors called ampullae of Lorenzini. Its wide head also helps it pin down prey such as stingrays against the seafloor. A common mix-up is assuming every hammerhead has exactly the same head shape: some are sharply T-shaped, while others have rounded or notched cephalofoils.