Yes, they really do spin—as many as seven rotations outside of the water and up to ten feet high. Acrobatic spinner dolphins also do leaps and mid-air somersaults. Why all the activity? Scientists believe the dolphins play to communicate with each other through echolocation, a type of hearing that helps them locate surrounding objects or regroup, into groups of up to 1,000, through sound. Even slapping the surface of water lets other dolphins know food, or danger, is nearby. Spinner dolphins also move just for fun. They’re known to approach boats and ride on the bow for up to 30 minutes!