( mit hot mineral-laden fluid that looks...)Hydrogen and methane provide raw energy for life at 'Lost City'

Carbonate minerals from fluids at Lost City drape nearby cliffs in brilliant white and form vents ranging in shape from tiny toadstools to the 18-story column, named Poseidon, which dwarfs most known black smoker vents by at least 100 feet. Some places resemble the sort of deposits one might see in spectacular caves with spires and smoothly rippled surfaces in a complex three-dimensional array, says Duke University's Jeffrey Karson, co-author on the paper.

Another marked difference being published for the first time this week concerns the diversity of life. The fluids at Lost City harbor large amounts of microorganisms ?comparable to what's found in rich organic sediments. However the diversity of species is low with, for example, just a handful of methane-producing and methane-consuming Archaea.

In surprising contrast, researchers discovered Lost City has a diversity of "larger" organisms that's as high, or higher, than any known black-smoker vent sites. Missing from Lost City are the tubeworms, abundant shrimp and other readily observed organisms that heavily blanket some black smokers. The high diversity revealed itself only after a 2003 expedition when the biology team led by Woods Hole Oceanographic Institution's Timothy Shank analyzed water samples "vacuumed" from around the vents.

"There aren't a lot of each kind of animal, most are only a centimeter in size and have translucent or invisible shells so it's no wonder we didn't suspect the actual diversity," says Kelley, who was chief scientist on the expedition, which like the 2000 voyage was funded by the National Science Foundation. Other large organisms include crabs, corals and fish.

Kelley will be co-principal investigator on another science expedition to Lost City this summer, without leaving the UW. She'll use state-of-the-art communication technology to help dir
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