noun - Hammerhead sharks
are a group of sharks
in the family Sphyrnidae. They are named for the unusual and distinctive structure of their heads, which are flattened and laterally extended into a hammer shape called a cephalofoil. Hammerheads
are found worldwide in warmer waters along coastlines and continental shelves. Unlike most sharks
usually swim in schools during the day, becoming solitary hunters at night. Some of these schools can be found near Malpelo Island in Colombia, Cocos Island off Costa Rica, near Molokai Island
in Hawaii, and Yonaguni Island
in Okinawa, Japan. Large schools are also seen in southern and eastern Africa.