A deep-sea vent. In some regions of the ocean floor, hot water containing sulfur compounds is released from the ground. The sulfur compounds provide energy for chemosynthetic bacteria, which then serve as food for many other species that live near the vents, including these rust-colored tube worms (Tevnia jerichonana) that have been stained orange by iron compounds emitted from the vents.
Photo by Peter Batson/Image Quest Marine.