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Chemosynthetic Environments. Katrina Pekar. What is it?. Chemosynthesis: The synthesis of organic compounds by energy derived from chemical changes or reactions Autotrophic bacteria synthesize the organic compounds
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Chemosynthetic Environments Katrina Pekar
What is it? • Chemosynthesis: The synthesis of organic compounds by energy derived from chemical changes or reactions • Autotrophic bacteria synthesize the organic compounds • Other animals either have a symbiotic relationship with the bacteria or prey upon other fauna http://www.rci.rutgers.edu/~carr/2003Lecture%2015%20MOR.pdf
Two Major Examples • Hydrothermal vents • Mid-ocean ridges • Cold seeps • Trenches, oil/natural gas rich areas of sea floor, brine pools, areas of methane hydrate
Hydrothermal vents Sulfide-rich High temps High pH (2.8) Associated with black smokers Cold seeps Methane-rich Very low temps Normal ocean pH Can be anywhere methane seeps out Comparison www.mbari.org/news/news_releases/2002/oct17_vrijenhoek.html www.mbayaq.org/efc/living_species/ default.asp?inhab=199
Hydrothermal vent fauna (modern) • Blind shrimp, giant white crabs, bivalves, a variety of tube worms • “Naked” snails: High pH prevents shell formation • Specialized characteristics • Metal-binding proteins in body systems • Metal expelling mucus in tubeworms http://www.rci.rutgers.edu/~carr/2003Lecture%2015%20MOR.pdf
Cold Seep fauna (modern) • Similar to vent fauna • Higher diversity • Less harsh environment or less limited dispersal • Still have autotrophic bacteria at the base of the food web
Ancient fauna example from Silurian • Bacteria, again • Brachiopods and monoplacophorans • Relatives of tube worms • Example from Yaman Kasy mine in the Urals of Russia: volcanogenic massive sulfide http://www.nhm.ac.uk/mineralogy/intro/project5/
In conclusion… • Thought to be origins of life on the Earth • Many life forms unique to environment (300+ species to date, 95% new to science) • Some have changed little from ancient relatives • Several fossilized analogs exist and are being studied