6. Ridge Crest Processes. This program includes a significant biological component. To 

 understand fully the origin and evolution of biological communities, a long-term integrated 

 biological program should be coupled to geochemical flux studies and directed toward the unique 

 properties of vent organisms with emphasis on chemolithotrophic microbes, symbiont-host 

 relations, bioenergetics, and physiological adaptations. 



To define community structure, life history stategies, and evolution of biological communities, a 

 number of important questions must be asl<ed. These include: What are the most important 

 factors sustaining vent biological communities - nutrients, heat, symbiosis? How do vent 

 communities colonize new areas? How do communities evolve? What are the mechanisms for 

 adaptation to the unique chemistry, high temperature, and high pressure? What are the 

 productivity and the physiology of vent organisms? 



7. Funding Requirements 



Funding requirements for the Program are detailed in Table C of Section IV. 



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