The National Science Foundation site reads:
1.5 miles beneath the oceans surface on the seafloor, exists a strange and fascinating world that thrives in the absence of sunlight. Hydrothermal vents support a rich ecosystem that includes fish, shrimp, tubeworms, mussels, crabs, and clams. Hydrothermal Vents can be found on the ocean floor in areas with volcanic activity, where cracks allow seawater to seep beneath the earthâ€™s crust. The water is heated up to 400 Â° C (756 Â° F) by the warmth of the Earthâ€™s mantle, and it comes gushing out in what looks like plumes of smoke. The â€˜smokeâ€™ is actually superheated water rich with dissolved chemicals and metals. In the absence of sunlight specially adapted bacteria and similar organisms called archaea are able to convert the chemicals into useable bio-energy. This process is analogous to plantsâ€™ ability to use sunlight. The bacteria are the base of a hydrothermal vent community and allow the ecosystem to both exist and flourish.
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