OLogy Cards > hydrothermal vents

Bountiful Bacteria of the Sea
The community of life around black smokers is like none other on Earth. Most ecosystems on the planet are based on organisms like plants that depend on sunlight to produce food. But the food chain at the hydrothermal vents is based on an entirely different organism. Tiny bacteria called Archaea use sulfides from the vents, instead of sunlight, to create food. They can survive extremely hot temperatures and toxic chemicals that would kill most organisms. All the other animals in this unusual community depend directly or indirectly on these bacteria. Plants cannot survive in these harsh conditions. Many animals, such as the tube worms, mussels, and clams, live in symbiosis with the bacteria: the bacteria living on or in their bodies supply them with nutrients, while they provide the bacteria with the sulfides they need to survive. (In a symbiotic relationship, two organisms live close together in a way that benefits at least one. In this case, both organisms benefit.) Some scientists believe that life on Earth—and possibly other planets—may have formed in environments similar to the one around the blacker smokers.