Mysterious Dolphins: Are Dolphins Smarter Than Us? Dolphins have always captured the imagination of humans. They are mammals and can interact with people in astounding ways. Like rescuing humans from drowning, performing complicated and difficult tasks and being able to understand. Now researchers are coming forward with evidence that dolphins can heal humans. How? When dolphins meet they greet each other with a series of whistles and clicks. Do dolphins have a language? If dolphins can speak, they may have been doing it longer than humans have ever existed. What might dolphins be able to tell us? Why would the U.S. military keep dolphin language breakthrough discoveries a secret?