how dolphins produce sounds they make

 how dolphins teach their young to identify signature whistles

the professor's experience with dolphins on a research boat

various ways dolphins communicate with each other 

 to view each other's bubble streams

 to hear each other's signature whistles

 to avoid interfering with other dolphins sonar clicks

 to keep mother's close to their young 

 they help protect dolphins from predators

their function is similar to that of signature whistles

 they do not appear to serve a communicative function

 dolphins use them to sense the movement of the water 

 to encourage students to do fieldwork

 to inform students about a paper she wrote

to show how scientists collect data on marine life

 to illustrate that dolphins are difficult to locate 

 the differences between land and marine mammals

 the importance of burst pulses as aware dolphins communicate

one reason dolphins travel in large groups

 one way dolphins use signature whistles