How Giant Tube Worms Survive at Hydrothermal Vents

In this episode, Ed talks to Colleen Cavanaugh and finds out how the tubeworm can live in complete darkness and, more curiously, without even having a mouth or anus. In a process called chemosynthesis, symbiotic bacteria inside the tubeworm use hydrogen sulfide spewed from the vents as an energy source for themselves and for the worms.