The largest vent field, called TAG , is about the size and shape of a football stadium . Other fields have more whimsical names like Clam Acres, Mussel Bed, Rose Garden, Garden of Eden, Broken Spur, and Lucky Strike. Snow Blower is named for the white, flaky bacteria discharged from its vents. Genesis is a vent that sputtered out but came back to life a few years later. Hydrothermal vents are underwater oases, providing habitat for many creatures that are not found anywhere else in the ocean. More than 300 new species have been identified since the first vent was discovered in 1977.
Besides the giant tube worms, which have so far been found only in the Pacific, there are pencil-size Jericho worms with accordion-like tubes; orange worms covered with tiny bristles; small benthic worms that wriggle through the mud ; and finger-length, dark red palm worms that stand upright, topped with wig-like fronds. A special class of small worms, called Alvinellids , live on the walls of mineral deposits that form around vents.
Mussels, shrimp , clams, and crabs are abundant at many vents, but these are not the same species that you find in seafood dishes. The cocktail-size shrimp that dominate vents in the mid-Atlantic, for example, have no eyes. However, at least on species has an extremely sensitive receptor on its head that may be used to detect heat or even dim light coming from vents. Scientists still arent sure how shrimp and other vent creatures cope with chemical-laden seawater that would kill ordinary shellfish.
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2016-02-26
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