LIFE AT RIDGE HYDROTHERMAL SYSTEMS

-HOT SPRINGS PROVIDE ENVIRONMENT FOR PREVIOUSLY UNKNOWN LIFE FORMS INCLUDING GIANT WORMS, CLAMS, AND CRABS

-THESE ARE THE FIRST EVER KNOWN THAT DO NOT ULTIMATELY DEPEND ON PHOTOSYNTHESIS AND THUS SUNLIGHT TO SURVIVE

-INSTEAD, THEY SURVIVE ON UNUSUAL BACTERIA, WHICH IN TURN USE CHEMICAL ENERGY (CHEMOSYNTHESIS) FROM H2S, CO2 AND O2 IN THE HOT SPRINGS

-THUS MIDOCEAN RIDGE HOT SPRINGS MAY BE HOW LIFE EVOLVED ON EARTH (BEFORE THERE WAS AN OXYGEN ATMOSPHERE)

-SIMILAR LFE FORMS MIGHT EXIST ON OTHER PLANETS