The most widely held reason that dolphins jump out of the water is so they can see a flock of birds that are eating, and they can go to the food. When dolphins eat, they take turns, like they are sharing. Bones Dolphins' bones are softer than the ones that land animals have. They are filled with fat and oil. There are only two bones where the hip bone and back legs used to be.
All dolphins have two flippers and a tail fin.
Most dolphins also have a dorsal fin on their backs. Another name for the tail fin is fluke. The dolphin uses its fluke to push itself forward in the water. There are no bones to hold up a dolphins' tail fin. Tough strands of tissue called ligaments harden the tail fin and attach it to the tail vertebrae.