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Organisms That Live On or Below the Ocean Bottom

The ocean bottom was initially deemed uninhabitable due to extreme pressures and lack of sunlight. Upon further investigation, however, scientists discovered ecosystems built around hydrothermal vents. Hydrothermal vents occur at deep ocean rifts where new crust forms.The mixture of sulfide-containing particles released from the vents produces ample energy to sustain life. Remarkable organisms inhabit the ocean bottom at recorded depths of 5,000 feet and temperatures as high as 380 degrees C.

Protists
- At the ocean's deepest point, scientists have discovered a species of single-celled protists that create their own shells called foraminifera. Members of the Protista kingdom are eukaryotes, which are characterized by having a membrane around the nucleus of their cells. The foraminifera are therefore not classified as fungi, bacteria, plants or animals. Foraminifera can survive at estimated depths as low as 36, 201 feet below sea level and have existed for millions of years, according to National Geographic.
Bacteria
- The bacteria that live in and underneath hydrothermal vents on the ocean floor are known as chemolithoautotrophs. They derive energy from the chemical reactions caused when sulfide-containing vent material is spewed into the ocean water. The bacteria oxidize hydrogen-sulfide for energy in a process similar to photosynthesis. These organisms are at the bottom of the food chain that supports the hydrothermal vent ecosystem.
Fungi
- Fungi are known to occur within deep-sea sediments on the ocean bottom. Large particulate matter, such as drift wood and decaying plant material, periodically drifts from the ocean shore into the deep ocean. Fungus slowly sinks to the ocean bottom and adapts to extreme pressures, according to the National Institute of Oceanography. Several aspergillus species, penicillium lagena and rhodotorula mucilaginosa commonly inhabit the ocean floor. These organisms decompose dead organisms and keep the bottom of the ocean clean.
Animals
- Several animals have a symbiotic relationship with the bacteria that live near hydrothermal vents. Riftia pachyptila, or the giant tube worm, filters bacteria into its body with its plume. A tube worm has no mouth, no digestive tract and no anus and can grow up to eight feet tall. It derives its energy from the bacteria that live inside it. Giant clams, mussels and snails also live along hydrothermal vents on the ocean bottom and process bacteria through their gills. Brown mussels, black snails and white snails are common varieties. Spider crabs have been spotted on the ocean bottom by scientists: They have been observed feeding on tube worms, according to the U.S. Geological Survey.

Nature