Unlike most animals, tubeworms do not have a mouth, gut, or anus. They completely lack a digestive system! Instead of “eating,” these animals get their food from a special symbiotic bacteria that live within their body in an organ called the trophosome. The trophosome is a large sac that is teeming with bacteria. These bacteria are chemosynthetic, and make food using energy derived from chemical reactions involving inorganic molecules, like Hydrogen Sulfide.
Hydrothermal vent tubeworms can grow incredibly fast with some species growing up to 85 centimeters (33 inches) per year. Vent tubeworms do not live as long as those on cold seeps. One possible reason for this is that hydrothermal vents are often found in volatile environments which leads to the vents being ephemeral, or short lived. This means that a vent that is active today, could be gone by the next dive or even the next day.