What physiology does a whale use to jump out of the water?

The behaviour is called breaching. It's not just Sperm Whales that do this, whales in general as well as rays and some sharks do this.

Why? Scientists are studying the behaviour and aren't sure why they do this. One theory is it's a way of communicating to one another. Think of it as a long distance communication system. Another theory is that it's a method of removing barnacles and other irritations from their skin.