OLogy Cards > giant tubeworms

The Deep Dark World of the Tubeworm
Miles below the ocean's surface is a mysterious world. The web of life that exists near the hydrothermal vents is different from every other one on Earth. Most food webs on Earth depend on plants, which get their energy from the Sun. But the thermal-vent food web is based on bacteria, which get their energy from the chemicals spewed by the vents. The main chemical near the vents is hydrogen sulfide. The giant tubeworm doesn't have a gut or mouth — it relies on the bacteria living inside its body for nutrition. The tubeworm provides the bacteria with oxygen, carbon dioxide, and chemicals transported from the outside by its blood. In return, the bacteria provide the tubeworm with nutrients. Both the giant tubeworms and the bacteria play crucial roles in the food web. Other animals live on and around the tubes, feeding on the tubeworm's flesh or on the bacteria.