small invertebrates associated with the carbonate structures, including small corals, snails, bivalves, polychaetes, amphipods, and ostracods. Desmophyllum corals and nematode worms have been observed living on the carbonate chimneys. Other animals such as tube worms and giant clams that are abundant in typical black smoker vents, however, are absent from Lost City. A variety of crabs, shrimp, sea fans, and jellyfish have also been observed at the field. Macrofauna are rare around the vent field, though larger organisms do visit the field on occasion. Visitors can include wreckfish, grenadiers, and even sharks. Arrowtooth Eel have been observed at the Lost City field, which have a massive depth range of to . Significance Lost City provides geologists, chemists, and biologists a working ecosystem for the study of life in extreme environments and other processes driven by abiotic production of methane and hydrogen by serpentinisation. Similarities to other locales The Lost City vent field shares a number of characteristics with the Prony Bay vent field near New Caledonia in the Pacific Ocean. Both are locations of moderate temperature which produce abundant hydrogen gas and methane. Prony Bay, however, is significantly shallower (less than ) than Lost City (around ). It is host to unique biology, including the extremophile Alkaliphilus hydrothermalis. A similar alkaline hydrothermal vent, the Strytan Hydrothermal Field, has been identified off the north coast of Iceland. The Von Damm Vent Field found in the Caribbean Sea is also situated atop an ocean core complex. Origin of life Speculation has been offered that ancient versions of similar alkaline hydrothermal vents in the seas of a young Earth were the birthplace of all life, constituting the planet's original abiogenesis. The free hydrogen gas produced, metallic catalysts consistent with an iron-sulfur world theory, micro-cellular physical structure of the towers, and available hydrothermal energy might plausibly have provided an environment for the beginnings of non-photosynthetic energy cycles common to the most primitive microorganisms and organic molecule creation. Microscopic structures in such alkaline vents "show interconnected compartments that provide an ideal hatchery for the origin of life". These alkaline hydrothermal vents also continuously generate acetyl thioesters, providing both the starting point for more complex organic molecules and the energy needed to produce them. However, this notion was rejected by Japanese researchers from Earth-Life Science Institute (ELSI), Tokyo Institute of Technology. They showed that because of the high free energy change of thioester hydrolysis and their