What are flippers and flukes?
The front limbs on a dolphin are called flippers. The bones inside the flippers are similar to the bones inside your arm and hand. Dolphins don't have any hind limbs. The dolphin's tail is called its flukes (each half is a fluke). There are no bones in a dolphin's flukes, just tough connective tissue. The dolphin uses its flukes for swimming and its flippers for steering. Most dolphins have a boneless dorsal fin in the middle of their back that works somewhat like the rudder on a boat. Like the flukes, the dorsal fin does not contain any bones.