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Events on Thursday 17 February 1977 1
1977Hydrothermal vents discovered on the ocean floorAlvin submersible finds life without sunlight near the GalapagosScientists aboard the submersible Alvin discovered hydrothermal vents on the Galapagos Rift, along with dense communities of tube worms and other organisms living off chemosynthesis. The find overturned assumptions that all life ultimately depends on sunlight.